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2630103
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12106
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12000000
37079000
9254000
43316104
5083428
1671596
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100000000
0.001
43316104
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14492000
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100417000
92875000
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6160000
100417000
15294000
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92876000
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220000000
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77587000
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77582000
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15288000
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15288000
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23001.40
25134.25
23691.44
24402.18
3425
15000000
10000000
5000000
5000
5000
15289000
15289000
296000
296000
1494514
13800000
2017-11-01
5800000
1000
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176730
15000000
296000
0.0850
1700000
5000
15289000
14091000
14091000
13795000
2800000
3.40
12.01
13795000
6.79
9.67
176730
0.0155
2018-12-31
0.71
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100000000
0.001
43050580
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13445000
6868000
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14364000
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623000
3904000
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110031000
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15262000
1000
15261000
15262000
1000
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334000
334000
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15000000
334000
14300000
11000
15262000
13445000
13445000
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11.31
13111000
8600000
228264
58580
3.06
274508
3.40
2500
10.00
5600000
2018-01-31
P20M22D
2014-08-01
5600000
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P1Y
0.690
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274508
183404
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52000
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-10569000
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ACRX
ACELRX PHARMACEUTICALS INC
false
Accelerated Filer
2014
10-Q
Delaware
2014-03-31
2005-07-13
0001427925
--12-31
Q1
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The following outstanding
shares of common stock equivalents were excluded from the
computation of diluted net loss per share of common stock for the
periods presented because including them would have been
antidilutive:</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="76%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="76%"></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>March 31,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2014</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Stock options to purchase
common stock</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5,083,428</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5,077,513</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Restricted stock
units</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">65,765</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Common stock
warrants</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,674,669</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2,908,036</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 18px"><font style="FONT-FAMILY: Times New Roman" size="2"><b>4. Collaboration
Agreement</b></font></p>
<!-- xbrl,body -->
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">On December 16, 2013,
AcelRx and Grünenthal GmbH, or Grünenthal, entered into a
Collaboration and License Agreement (the “License
Agreement”) and related Manufacture and Supply Agreement (the
“Manufacturing Agreement” and together with the License
Agreement, the “Grünenthal Agreements”). The
License Agreement grants Grünenthal rights to commercialize
Zalviso in the EU, Switzerland, Liechtenstein, Iceland, Norway and
Australia, for pain treatment within or dispensed by hospitals,
hospices, nursing homes and other medically-supervised settings.
Under the Supply Agreement, the Company will exclusively
manufacture and supply Zalviso to Grünenthal for sale in their
territories.</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 18px">
 </p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><u>License
Agreement</u></font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">Under the terms of the
License Agreement, Grünenthal has the exclusive right to
commercialize Zalviso in their territories. The Company retains
control of clinical development, and together with Grünenthal
will be responsible for certain development activities. The Company
will not receive separate payment for such development activities.
Grünenthal is responsible for marketing approval applications
and other regulatory filings relating to the sufentanil drug
cartridge for Zalviso, while the Company is responsible for the CE
Mark and other regulatory filings relating to the device
portions.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The Company received an
upfront non-refundable cash payment of $30.0 million, and is
eligible to receive up to $220.0 million in additional payments
contingent upon research, development, regulatory and manufacturing
efforts and specified net sales target milestones. Grünenthal
will also make tiered royalty and supply and trademark fee payments
in the mid-teens up to the mid-twenties percent range on net sales
of Zalviso.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">Unless earlier terminated,
the License Agreement continues in effect until the expiration of
the obligation of Grünenthal to make royalty and supply and
trademark fee payments, which supply and trademark fee continues
for so long as the Company continues to supply Zalviso to
Grünenthal. The License Agreement is subject to earlier
termination in the event the parties mutually agree, by a party in
the event of an uncured material breach by the other party, upon
the bankruptcy or insolvency of either party, or by Grünenthal
for convenience.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 18px"><font style="FONT-FAMILY: Times New Roman" size="2"><u>Manufacturing
Agreement</u></font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">Under the terms of the
Manufacturing Agreement, the Company will manufacture and supply
Zalviso exclusively for Grünenthal. The Company will supply
Zalviso at the Company’s fully burdened manufacturing cost
(as defined in the Manufacturing Agreement). The Manufacturing
Agreement requires the Company to use commercially reasonable
efforts to enter stand-by contracts with third party contract
manufacturers to ensure continual supply of Zalviso and under
certain conditions permits Grünenthal to use a third party
back-up manufacturer to manufacture Zalviso for commercial sale in
their territories.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">Unless earlier terminated,
the Manufacturing Agreement continues in effect until the later of
the expiration of the obligation of Grünenthal to make royalty
and supply and trademark fee payments or the end of any transition
period for manufacturing obligations due to the expiration or
termination of the License Agreement. The Manufacturing Agreement
is subject to earlier termination in connection with certain
termination events in the License Agreement, in the event the
parties mutually agree, by a party in the event of an uncured
material breach by the other party or upon the bankruptcy or
insolvency of either party.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The Company identified the
following four significant non-contingent performance deliverables
under the agreements: 1) intellectual property (license), 2) the
obligation to provide research and development services, 3) the
significant and incremental discount on the manufacturing of
Zalviso for commercial purposes, and 4) the obligation to
participate on the joint steering committee. The Company developed
best estimates of selling prices for each deliverable in order to
allocate the non-contingent arrangement consideration to the four
units of accounting.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The Company’s
management determined the best estimate of selling price for the
license based on Grünenthal’s estimated future cash
flows arising from the arrangement. Embedded in the estimate were
significant assumptions regarding regulatory expenses, revenue,
including potential customer market for the product and product
price, costs to manufacture the product and the discount rate. The
Company’s management determined the best estimate of selling
price of the research and development services and committee
participation based on the nature and timing of the services to be
performed and in consideration of personnel and other costs
incurred in the delivery of the services. For the discount on
manufacturing services, the Company’s management estimated
the selling price based on the market level of contract
manufacturing margin it could have received if it were engaged to
supply products to a customer in a separate transaction.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The Agreements entitle the
Company to receive additional payments upon the achievement of
certain development and sales milestones. Based on ASC Topic
605-28, <i>Revenue Recognition — Milestone Method</i>, the
Company evaluates contingent milestones at the inception of the
agreement, and recognizes consideration that is contingent upon the
achievement of a milestone in its entirety as revenue in the period
in which the milestone is achieved only if the milestone is
considered substantive in its entirety. Milestones are events which
have the following characteristics: (i) they can be achieved
based in whole or in part on either the Company’s performance
or on the occurrence of a specific outcome resulting from the
Company’s performance, (ii) there was substantive
uncertainty at the date the agreement was entered into that the
event would be achieved and, (iii) they would result in
additional payments due to the Company. A milestone is considered
substantive if the following criteria are met: (i) the
consideration is commensurate with either (1) the
entity’s performance to achieve the milestone, or
(2) the enhancement of the value of the delivered item
(s) as a result of a specific outcome resulting from the
entity’s performance to achieve the milestone, (ii) the
consideration relates solely to past performance and,
(iii) the consideration is reasonable relative to all of the
other deliverables and payment terms, including other potential
milestone consideration, within the arrangement.</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 12px">
 </p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 0px"><font style="FONT-FAMILY: Times New Roman" size="2">The substantive milestone
payments will be recognized as revenue in their entirety upon the
achievement of each substantive milestone. Based on the criteria
noted above, the identified substantive milestones in the agreement
pertain to post-approval product enhancements, expanded market
opportunities and manufacturing efficiencies for Zalviso. Each of
these potential achievements is based primarily on the
Company’s performance and involves substantive uncertainty as
achievement of these milestones requires future research,
development and regulatory activities, which are inherently
uncertain in nature. The Company determined that the consideration
for each milestone was commensurate with the Company’s
performance to achieve the milestone, including future research,
development, manufacturing and regulatory activities and that the
consideration is reasonable relative to all of the other
deliverables and payments within the arrangement. Aggregate
potential payments for these milestones total
$28.5 million.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">In addition to substantive
milestones, two milestones associated with the Agreements were
deemed not to be substantive. These milestones pertain to
regulatory developments for Zalviso in Europe, which
Company’s management deemed to be not substantive due to the
level of performance associated with future achievement of these
milestones. Aggregate potential payments for these milestones total
$20.0 million. When achieved, the value of these milestones will be
allocated to the four separate units of accounting based on
estimated selling prices and recognized as revenue in the period of
achievement to the extent the services underlying the separate
units of accounting have been performed. The Company anticipates
receiving the first milestone payment of $5.0 million in 2014,
for the submission of the Marketing Authorization Application for
Zalviso to the European Medicines Agency.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The Agreements also include
milestone payments related to specified net sales targets, totaling
$171.5 million. The sales-based milestones do not meet the
definition of a milestone under ASU 2010-17 because the achievement
of these milestones is solely dependent on counter-party
performance and not on any performance obligations of the
Company.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The Company allocated the
$30.0 million upfront fee across the four deliverables based on
estimated selling prices and for the quarter ended
December 31, 2013, recognized $27.4 million attributable to
the license. The remaining $2.6 million was recorded as deferred
revenue at December 31, 2013, to be recognized in future
periods to the extent services are performed related to the other
non-contingent performance deliverables under the
agreements.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The Company recognized
$95,000 of previously deferred revenue related to research and
development services under the collaboration agreement during the
three months ended March 31, 2014. As of March 31, 2014,
the Company had a deferred revenue balance of $2.5 million.
There were no milestone payments received or recognized under these
Agreements during the three months ended March 31,
2014.</font></p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The following tables set
forth a summary of the changes in the fair value of the
Company’s Level III financial liabilities for the three
months ended March 31, 2014 and March 31, 2013 (in
thousands):</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="84%"></td>
<td valign="bottom" width="10%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three Months<br />
Ended<br />
March 31,<br />
2014</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Fair value—beginning
of period</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">13,445</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Change in fair value of
PIPE warrants</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">684</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Change in fair value of
contingent put option associated with Amended Loan Agreement with
Hercules</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(38</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Fair value—end of
period</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">14,091</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
</tr>
<tr>
<td height="16"></td>
<td height="16" colspan="4"></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three Months<br />
Ended<br />
March 31,<br />
2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Fair value—beginning
of period</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">7,500</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Change in fair value of
PIPE warrants</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,776</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Change in fair value of
contingent put option associated with Original Loan Agreement with
Hercules</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(22</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Fair value—end of
period</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">9,254</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The following table sets
forth the fair value of the Company’s financial assets and
liabilities by level within the fair value hierarchy (in
thousands):</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="92%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="66%"></td>
<td valign="bottom" width="4%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="4%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="4%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="2%"></td>
<td></td>
<td></td>
<td valign="bottom" width="2%"></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="14" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>As of March 31,
2014</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Fair Value</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Level I</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Level II</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Level III</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2"><b><u>Assets</u></b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Money market
funds</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">U.S. government agency
obligations</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,289</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,289</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total assets measured at
fair value</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,294</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,289</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2"><b><u>Liabilities</u></b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">PIPE warrants</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">13,795</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">13,795</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Contingent put option
liability</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">296</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">296</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total liabilities measured
at fair value</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">14,091</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">14,091</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
</tr>
<tr>
<td height="16"></td>
<td height="16" colspan="16"></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="14" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>As of December 31,
2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Fair Value</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Level I</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Level II</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Level III</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2"><b><u>Assets</u></b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Money market
funds</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">11</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">11</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">U.S. government agency
obligations</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,262</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,262</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total assets measured at
fair value</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,273</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">11</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,262</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2"><u><b>Liabilities</b></u></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">PIPE warrants</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">13,111</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">13,111</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Contingent put option
liability</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">334</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">334</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total liabilities measured
at fair value</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">13,445</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">13,445</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
</tr>
</table>
</div>
43190409
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt">
The following table sets forth the computation of the
Company’s basic and diluted net loss per share of common
stock during the three months ended March 31, 2014 and 2013
(in thousands, except for share and per share amounts):</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="76%" align="center" border="0">
<tr>
<td width="71%"></td>
<td valign="bottom" width="9%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="9%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"><b>Three Months Ended<br />
March 31,</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2014</b></td>
<td valign="bottom"> </td>
<td valign="bottom"> </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2013</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Net loss</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">(9,631</td>
<td valign="bottom" nowrap="nowrap">) </td>
<td valign="bottom"> </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">(12,762</td>
<td valign="bottom" nowrap="nowrap">) </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Shares used in computing net loss per share of common stock, basic
and diluted</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">43,190,409</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt"> </font></td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">37,133,358</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Net loss per share of common stock, basic and diluted</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">(0.22</td>
<td valign="bottom" nowrap="nowrap">) </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt"> </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">(0.34</td>
<td valign="bottom" nowrap="nowrap">) </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 18px"><font style="FONT-FAMILY: Times New Roman" size="2"><b>5. Long-Term
Debt</b></font></p>
<!-- xbrl,body -->
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Hercules Loan and
Security Agreements</i></b></font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">In June 2011, AcelRx
entered into a Loan and Security Agreement, or the Original Loan
Agreement, with Hercules Technology II, L.P. and Hercules
Technology Growth Capital, Inc., collectively referred to as
Hercules, under which AcelRx borrowed $20.0 million in two tranches
of $10.0 million each, represented by secured convertible term
promissory notes, or collectively, the Original Notes. The
Company’s obligations associated with the agreement were
secured by a security interest in substantially all of its assets,
other than its intellectual property.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The Company borrowed the
first tranche of $10.0 million upon the closing of the transaction
on June 29, 2011 and borrowed the second tranche of $10.0
million in December 2011. The interest rate for each tranche
was 8.50%. In connection with the Original Loan Agreement, the
Company issued Hercules seven-year warrants to purchase an
aggregate of 274,508 shares of common stock at a price of $3.06 per
share. See Note 6 “Warrants,” for further
description.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">On December 16, 2013,
AcelRx entered into an Amended and Restated Loan and Security
Agreement, or the Amended Loan Agreement, with Hercules, under
which the Company may borrow up to $40.0 million in three tranches.
These loans are represented by secured convertible term promissory
notes, or collectively, the Amended Notes. The Amended Loan
Agreement amends and restates the Original Loan Agreement, as noted
above. The Company borrowed the first tranche of $15.0 million upon
closing of the transaction on December 16, 2013. The Company
used approximately $8.6 million of the proceeds from the first
tranche to repay its obligations under the Original Loan Agreement.
The Company recorded the new debt at estimated fair value, $14.3
million, as of December 31, 2013.</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 12px">
 </p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 0px"><font style="FONT-FAMILY: Times New Roman" size="2">The second tranche of the
Amended Loan Agreement of up to $10.0 million can be drawn, at the
Company’s option, any time prior to June 30, 2014. The
third tranche, of up to $15.0 million, can be drawn at any time
between December 15, 2014 and March 15, 2015, but only if
the Company has obtained approval for Zalviso from the U.S. Food
and Drug Administration, or the Milestone. The interest rate for
each tranche will be calculated at a rate equal to the greater of
either (i) 9.10% plus the prime rate as reported from time to
time in The Wall Street Journal minus 5.25%, and (ii) 9.10%.
Payments under the Amended Loan Agreement are interest only until
April 1, 2015 (which will be extended until January 1,
2016 if the Company achieves the Milestone on or before
April 1, 2015) followed by equal monthly payments of principal
and interest through the scheduled maturity date on October 1,
2017 (which would be extended until January 1, 2018 if the
Company achieves the Milestone on or prior to April 1, 2015),
or the Loan Maturity Date. In addition, a final payment equal to
$1,700,000 will be due on the Loan Maturity Date, or such earlier
date specified in the Amended Loan Agreement. The Company’s
obligations under the Amended Loan Agreement are secured by a
security interest in substantially all of its assets, other than
its intellectual property.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">If the Company prepays the
Amended Loan Agreement prior to maturity, it will pay Hercules a
prepayment charge, based on a percentage of the then outstanding
principal balance, equal to 3% if the prepayment occurs prior to
December 16, 2014, 2% if the prepayment occurs after
December 16, 2014, but prior to December 16, 2015, or 1%
if the prepayment occurs after December 16, 2015.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">Subject to certain
conditions and limitations set forth in the Amended Loan Agreement,
the Company has the right to convert up to $5.0 million
of scheduled principal installments under the Notes into freely
tradeable shares of the Company’s common stock, or Common
Stock. The number of shares of Common Stock that would be issued
upon conversion of the Amended Notes would be equal to the number
determined by dividing (x) the product of (A) the
principal amount to be paid in shares of Common Stock and
(B) 103%, by (y) $9.30 (subject to certain proportional
adjustments as provided for in the Amended Loan
Agreement).</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The Amended Loan Agreement
includes customary affirmative and restrictive covenants, but does
not include any financial maintenance covenants, and also includes
standard events of default, including payment defaults, breaches of
covenants following any applicable cure period, a material
impairment in the perfection or priority of Hercules’
security interest or in the value of the collateral, and events
relating to bankruptcy or insolvency. Upon the occurrence of an
event of default, a default interest rate of an additional 5% may
be applied to the outstanding loan balances, and Hercules may
declare all outstanding obligations immediately due and payable and
take such other actions as set forth in the Amended Loan
Agreement.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">In connection with the
Amended Loan Agreement, the Company issued a warrant to each Lender
which, collectively, are exercisable for an aggregate of 176,730
shares of Common Stock and each carry an exercise price of $6.79.
See Note 6 “Warrants,” for further
description.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">Upon an event of default,
including a change of control, Hercules has the option to
accelerate repayment of the Amended Loan Agreement, including
payment of any applicable prepayment charges, which range from
1%-3% of the outstanding loan balance and accrued interest, as well
as a final payment fee of $1.7 million. This option is considered a
contingent put option liability, as the holder of the loan may
exercise the option in the event of default, and is considered an
embedded derivative, which must be valued and separately accounted
for in the Company’s financial statements. As the amendment
of the loan agreement was considered an extinguishment, the
contingent put option liability associated with the Original Loan
Agreement, which had an estimated fair value of $32,000 at the time
of the amendment, was written off as a part of the loss on
extinguishment, and a new contingent put option liability was
established. As of March 31, 2014 and December 31, 2013,
the estimated fair value of the contingent put option liability was
$296,000 and $334,000, respectively, which was determined by using
a risk-neutral valuation model, wherein the fair value of the
underlying debt facility is estimated both with and without the
presence of the default provisions, holding all other assumptions
constant. The resulting difference between the two estimated fair
values is the estimated fair value of the default provisions, or
the contingent put option. The fair value of the underlying debt
facility is estimated by calculating the expected cash flows in
consideration of an estimated probability of default and expected
recovery rate in default, and discounting such cash flows back to
the reporting date using a risk-free rate. The contingent put
option liability was recorded as a debt discount to the loan and
consequently a reduction to the carrying value of the loan. The
contingent put option liability is revalued at the end of each
reporting period and any change in the fair value is recognized in
interest income and other income (expense), net in the condensed
statements of comprehensive loss.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">As of March 31, 2014
and December 31, 2013, the Company had outstanding borrowings
under the Amended Loan Agreement of $15.0 million. Interest expense
related to the Amended Loan Agreement was $472,000 for the three
months ended March 31, 2014, $128,000 of which represented
amortization of the debt discount. Interest expense related to the
Original Loan Agreement was $454,000 for the three months ended
March 31, 2013, $108,000 of which represented amortization of
the debt discount.</font></p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The table below summarizes
the Company’s cash, cash equivalents and investments (in
thousands):</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="92%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="50%"></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="4%"></td>
<td></td>
<td></td>
<td valign="bottom" width="4%"></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="14" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>As of March 31,
2014</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Amortized Cost</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Gross Unrealized<br />
Gains</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Gross Unrealized<br />
Losses</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Fair<br />
Value</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Cash and cash
equivalents:</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 3em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Cash</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">77,582</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">77,582</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 3em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Money market
funds</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total cash and cash
equivalents</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">77,587</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">77,587</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Marketable
securities:</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 3em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">U.S. government agency securities</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,288</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,289</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total marketable
securities</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,288</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,289</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total cash, cash
equivalents and investments</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">92,875</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">92,876</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
</tr>
<tr>
<td height="16"></td>
<td height="16" colspan="16"></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="14" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>As of December 31,
2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Amortized Cost</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Gross Unrealized<br />
Gains</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Gross Unrealized<br />
Losses</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Fair<br />
Value</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Cash and cash
equivalents:</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 3em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Cash</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">88,390</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">88,390</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 3em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Money market
funds</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">11</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">11</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total cash and cash
equivalents</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">88,401</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">88,401</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Marketable
securities:</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 3em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">U.S. government agency securities</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,261</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,262</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total marketable
securities</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,261</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,262</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total cash, cash
equivalents and investments</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">103,662</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">103,663</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2"><b>1. Organization and
Summary of Significant Accounting Policies</b></font></p>
<!-- xbrl,body -->
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>The
Company</i></b></font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">AcelRx Pharmaceuticals,
Inc., or the Company or AcelRx, was incorporated in Delaware on
July 13, 2005 as SuRx, Inc., and in January 2006, the Company
changed its name to AcelRx Pharmaceuticals, Inc. The
Company’s operations are based in Redwood City,
California.</font></p>
<p style="MARGIN-BOTTOM: 0px; PADDING-BOTTOM: 0px; MARGIN-TOP: 12px">
<font style="FONT-FAMILY: Times New Roman" size="2">AcelRx is a
specialty pharmaceutical company focused on the development and
commercialization of innovative therapies for the treatment of
acute and breakthrough pain. AcelRx intends to commercialize its
product candidates in the United States and license the development
and commercialization rights to its product candidates for sale
outside of the United States through strategic partnerships and
collaborations. The Company’s lead product candidate,
Zalviso</font><font style="FONT-FAMILY: Times New Roman" size="1"><sup style="VERTICAL-ALIGN: baseline; POSITION: relative; BOTTOM: 0.8ex">TM</sup></font><font style="FONT-FAMILY: Times New Roman" size="2">, formerly known as the Sufentanil NanoTab
patient-controlled analgesia, or PCA, System, or ARX-01. The New
Drug Application, or NDA, for Zalviso is currently under review by
the FDA. The proposed indication for Zalviso is for the management
of moderate-to-severe acute pain in adult patients in the hospital
setting. In addition, in December 2013, the Company entered into a
collaboration agreement with Grünenthal, a European-based
pharmaceutical company, for the commercialization of Zalviso in
Europe and Australia. We anticipate the filing of the Marketing
Authorization Application, or MAA, for Zalviso under the
centralized procedure in the European Union, or EU, in
mid-2014.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The Company has incurred
recurring operating losses and negative cash flows from operating
activities since inception and expects to continue to incur
negative cash flows until its product candidates are approved for
marketing in the United States and other countries, in which it has
and intends to license its products, which may never occur. In
previous years, prior to the completion of the clinical development
program for Zalviso and the commercial collaboration of Zalviso,
AcelRx was considered a development stage company.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The Company has one
business activity, which is the development and commercialization
of product candidates for the treatment of pain, and a single
reporting and operating unit structure.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 18px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Basis of
Presentation</i></b></font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">The accompanying unaudited
condensed financial statements have been prepared in accordance
with accounting principles generally accepted in the United States
for interim financial information and the rules and regulations of
the U.S. Securities and Exchange Commission, or SEC. Accordingly,
they do not include all of the information and footnotes required
by accounting principles generally accepted in the United States
for complete financial statements. In the opinion of management,
all adjustments (consisting of normal recurring adjustments)
considered necessary for a fair presentation have been
included.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">Operating results for the
three months ended March 31, 2014, are not necessarily
indicative of the results that may be expected for the year ending
December 31, 2014. The condensed balance sheet as of
December 31, 2013, was derived from the Company’s
audited financial statements as of December 31, 2013, included
in the Company’s Annual Report on Form 10-K filed with the
SEC. These financial statements should be read in conjunction with
the Company’s Annual Report on Form 10-K for the year ended
December 31, 2013, which includes a broader discussion of the
Company’s business and the risks inherent therein.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 18px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Use of
Estimates</i></b></font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">The preparation of
financial statements in conformity with accounting principles
generally accepted in the United States requires management to make
estimates and assumptions that affect the amounts reported in the
condensed financial statements and accompanying notes. Management
evaluates its estimates on an ongoing basis including critical
accounting policies. Estimates are based on historical experience
and on various other market-specific and other relevant assumptions
that the Company believes to be reasonable under the circumstances,
the results of which form the basis for making judgments about the
carrying values of assets and liabilities that are not readily
apparent from other sources. Actual results could differ from those
estimates.</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 18px">
 </p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Newly Adopted
Accounting Pronouncements</i></b></font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">There have been no recent
accounting pronouncements or changes in accounting pronouncements
during the three months ended March 31, 2014, as compared to
the recent accounting pronouncements described in the
Company’s Form 10-K for the year ended December 31,
2013, that are of significance, or potential significance to the
Company.</font></p>
</div>
-10132000
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 18px"><font style="FONT-FAMILY: Times New Roman" size="2"><b>8. Net Loss per Share of
Common Stock</b></font></p>
<!-- xbrl,body -->
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">The following table sets
forth the computation of the Company’s basic and diluted net
loss per share of common stock during the three months ended
March 31, 2014 and 2013 (in thousands, except for share and
per share amounts):</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="76%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="71%"></td>
<td valign="bottom" width="9%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="9%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three Months Ended<br />
March 31,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2014</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Net loss</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(9,631</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(12,762</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Shares used in computing
net loss per share of common stock, basic and diluted</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">43,190,409</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">37,133,358</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Net loss per share of
common stock, basic and diluted</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(0.22</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(0.34</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom"> </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
</tr>
<!-- End Table Body --></table>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The following outstanding
shares of common stock equivalents were excluded from the
computation of diluted net loss per share of common stock for the
periods presented because including them would have been
antidilutive:</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="76%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="76%"></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="3%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="6" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>March 31,</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2014</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Stock options to purchase
common stock</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5,083,428</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5,077,513</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Restricted stock
units</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">65,765</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Common stock
warrants</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,674,669</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">2,908,036</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 18px"><font style="FONT-FAMILY: Times New Roman" size="2"><b>3. Research Grant
Agreement</b></font></p>
<!-- xbrl,body -->
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">In May 2011, AcelRx
received a grant from the US Army Medical Research and Materiel
Command, or USAMRMC, in which the USAMRMC granted $5.6 million to
the Company in order to support the development of a new product
candidate, ARX-04, a sufentanil tablet for the treatment of
moderate-to-severe acute pain. Under the terms of the grant, the
USAMRMC reimbursed the Company for development, manufacturing and
clinical costs necessary to prepare for and complete the planned
Phase 2 dose-finding trial in a study of acute moderate-to-severe
pain, and to prepare to enter Phase 3 development. The grant gives
the USAMRMC the option to extend the term of the grant and provide
additional funding for the research. As of December 31, 2013,
the full amount of the grant, $5.6 million, had been received and
recognized as revenue.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">Revenue is recognized based
on expenses incurred by AcelRx in conducting research and
development activities set forth in the agreement. Revenue
attributable to the research and development performed under the
USAMRMC grant was $0 and $940,000 for the three months ended
March 31, 2014 and 2013, respectively.</font></p>
</div>
Milestones are events which have the following characteristics: (i) they can be achieved based in whole or in part on either the Company’s performance or on the occurrence of a specific outcome resulting from the Company’s performance, (ii) there was substantive uncertainty at the date the agreement was entered into that the event would be achieved and, (iii) they would result in additional payments due to the Company. A milestone is considered substantive if the following criteria are met: (i) the consideration is commensurate with either (1) the entity’s performance to achieve the milestone, or (2) the enhancement of the value of the delivered item (s) as a result of a specific outcome resulting from the entity’s performance to achieve the milestone, (ii) the consideration relates solely to past performance and, (iii) the consideration is reasonable relative to all of the other deliverables and payment terms, including other potential milestone consideration, within the arrangement.
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt">
The Company recorded total stock-based compensation expense for
stock options, stock awards and the 2011 Employee Stock Purchase
Plan as follows (in thousands):</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="76%" align="center" border="0">
<tr>
<td width="82%"></td>
<td valign="bottom" width="6%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="6%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td valign="bottom" colspan="6" align="center">
<b>Three Months Ended</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"><b>March 31,</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2014</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2013</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Expenses:</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Research and development</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">479</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">355</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
General and administrative</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">496</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">402</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 5em; TEXT-INDENT: -1em">
Total stock-based compensation expense</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">975</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">757</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b><i>Use of Estimates</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt">
The preparation of financial statements in conformity with
accounting principles generally accepted in the United States
requires management to make estimates and assumptions that affect
the amounts reported in the condensed financial statements and
accompanying notes. Management evaluates its estimates on an
ongoing basis including critical accounting policies. Estimates are
based on historical experience and on various other market-specific
and other relevant assumptions that the Company believes to be
reasonable under the circumstances, the results of which form the
basis for making judgments about the carrying values of assets and
liabilities that are not readily apparent from other sources.
Actual results could differ from those estimates.</p>
</div>
The interest rate for each tranche will be calculated at a rate equal to the greater of either (i) 9.10% plus the prime rate as reported from time to time in The Wall Street Journal minus 5.25%, and (ii) 9.10%.
-0.22
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 18px"><font style="FONT-FAMILY: Times New Roman" size="2"><b>10. Subsequent
Event</b></font></p>
<!-- xbrl,body -->
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px; TEXT-INDENT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2">In May 2014,
the Company entered into an amendment, or the Lease Amendment, to
that certain lease dated December 21, 2011, with Metropolitan
Life Insurance Company, or the Existing Lease, for 13,787 square
feet of space located at 301 Galveston Drive, Redwood City,
California, or the Current Premises. Pursuant to the Lease
Amendment, the term of the Existing Lease has been extended for a
period of twenty (20) months and twenty-two (22) days and
expiring January 31, 2018, or the Expiration Date, unless
sooner terminated pursuant to the terms of the Existing Lease. In
addition, the Lease Amendment included a new lease on an additional
12,106 square feet of office space, or the Expansion Space, which
is adjacent to the current premises. The new lease for the
Expansion Space has a term of 42 months commencing on
August 1, 2014, and expiring on the Expiration Date. The
Company has an option to extend the term of the Lease Amendment for
an additional five years, which would commence upon the Expiration
Date, at a market rate determined according to the Existing
Lease.</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<!-- /xbrl,ns -->
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 12px">
 </p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 0px; TEXT-INDENT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2">Base rent
payable under the Lease Amendment during the Extended Term for the
Current Premises will be as follows:</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="84%"></td>
<td valign="bottom" width="6%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom" nowrap="nowrap">
<p style="BORDER-BOTTOM: rgb(0,0,0) 1px solid; WIDTH: 50pt">
<font style="FONT-FAMILY: Times New Roman" size="1"><b>Period
from/to</b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Monthly Base<br />
Rent</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">May 9, 2016 to
May 8, 2017</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">35,961.55</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">May 9, 2017 to
January 31, 2018</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">37,040.40</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<!-- End Table Body --></table>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px; TEXT-INDENT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2">Base rent
payable under the Lease Amendment for the Expansion Space,
commencing August 1, 2014, will be as follows:</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="84%"></td>
<td valign="bottom" width="6%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom" nowrap="nowrap">
<p style="BORDER-BOTTOM: rgb(0,0,0) 1px solid; WIDTH: 77pt">
<font style="FONT-FAMILY: Times New Roman" size="1"><b>Months of
Lease Term</b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Monthly Base<br />
Rent</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">1-12</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">23,001.40</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">13-24</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">23,691.44</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">25-36</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">24,402.18</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">37-42</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">25,134.25</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<!-- End Table Body --></table>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px; TEXT-INDENT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2">In addition,
the Company will pay the Landlord specified percentages of certain
operating expenses and taxes related to the leased facility
incurred by the Landlord.</font></p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 18px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Basis of
Presentation</i></b></font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">The accompanying unaudited
condensed financial statements have been prepared in accordance
with accounting principles generally accepted in the United States
for interim financial information and the rules and regulations of
the U.S. Securities and Exchange Commission, or SEC. Accordingly,
they do not include all of the information and footnotes required
by accounting principles generally accepted in the United States
for complete financial statements. In the opinion of management,
all adjustments (consisting of normal recurring adjustments)
considered necessary for a fair presentation have been
included.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">Operating results for the
three months ended March 31, 2014, are not necessarily
indicative of the results that may be expected for the year ending
December 31, 2014. The condensed balance sheet as of
December 31, 2013, was derived from the Company’s
audited financial statements as of December 31, 2013, included
in the Company’s Annual Report on Form 10-K filed with the
SEC. These financial statements should be read in conjunction with
the Company’s Annual Report on Form 10-K for the year ended
December 31, 2013, which includes a broader discussion of the
Company’s business and the risks inherent therein.</font></p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt">
<b>7. Stock-Based Compensation</b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt">
The Company recorded total stock-based compensation expense for
stock options, stock awards and the 2011 Employee Stock Purchase
Plan as follows (in thousands):</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt">
 </p>
<table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="76%" align="center" border="0">
<tr>
<td width="82%"></td>
<td valign="bottom" width="6%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="6%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td valign="bottom" colspan="6" align="center">
<b>Three Months Ended</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"><b>March 31,</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2014</b></td>
<td valign="bottom"> </td>
<td valign="bottom">  </td>
<td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"><b>2013</b></td>
<td valign="bottom"> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em">
Expenses:</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
Research and development</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">479</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">355</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em">
General and administrative</p>
</td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">496</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom">  </td>
<td valign="bottom"> </td>
<td valign="bottom" align="right">402</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
<td valign="top">
<p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 5em; TEXT-INDENT: -1em">
Total stock-based compensation expense</p>
</td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">975</td>
<td valign="bottom" nowrap="nowrap">  </td>
<td valign="bottom"><font style="FONT-SIZE: 8pt">  </font></td>
<td valign="bottom">$</td>
<td valign="bottom" align="right">757</td>
<td valign="bottom" nowrap="nowrap">  </td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: #000000 3px double"> </p>
</td>
<td> </td>
</tr>
</table>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt">
As of March 31, 2014 there were 1,671,596 shares available for
grant, 5,083,428 options outstanding and 0 restricted stock units
outstanding under the Company’s 2011 Equity Incentive
Plan.</p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt">
<b><i>Newly Adopted Accounting Pronouncements</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt">
There have been no recent accounting pronouncements or changes in
accounting pronouncements during the three months ended
March 31, 2014, as compared to the recent accounting
pronouncements described in the Company’s Form 10-K for
the year ended December 31, 2013, that are of significance, or
potential significance to the Company.</p>
</div>
1143000
-8541000
420000000
30000000
1359000
95000
195000
0
-9631000
0
-618000
-9631000
-72000
-29000
3925000
560000
975000
-10814000
131000
8636000
-95000
-2012000
472000
-156000
0
162000
1260000
95000
-1242000
4711000
0
0
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 18px"><font style="FONT-FAMILY: Times New Roman" size="2"><b>9. Manufacturing
Agreements</b></font></p>
<!-- xbrl,body -->
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2"><i><u>Patheon</u></i></font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">In January 2013, the
Company and Patheon Pharmaceuticals Inc., or Patheon, entered into
a Manufacturing Services Agreement, or the Services Agreement, and
a related Amended and Restated Capital Expenditure and Equipment
Agreement, or the Capital Agreement, relating to the manufacture of
sufentanil tablets, or the Product, for use with the
Company’s sufentanil sublingual tablet system, or
ARX-01.</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 12px">
 </p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 0px"><font style="FONT-FAMILY: Times New Roman" size="2">Under the terms of the
Services Agreement, the Company has agreed to purchase, subject to
Patheon’s continued material compliance with the terms of the
Services Agreement, all of its Product requirements for the United
States, Canada and Mexico from Patheon during the Initial Term of
the Services Agreement (as defined below), and at least eighty
percent (80%) of its Product requirements for such territories
after the Initial Term.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The term of the Services
Agreement extends until December 31, 2017, or the Initial
Term, and will automatically renew thereafter for periods of two
years, unless terminated by either party upon eighteen
months’ prior written notice; provided, however, that the
Services Agreement may not be terminated without cause prior to the
end of the Initial Term.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The Company also entered
into a Capital Expenditure and Equipment Agreement, or the Capital
Agreement. Under the terms of the Capital Agreement, as amended in
January 2014, the Company has made and continues to make certain
modifications to Patheon’s Cincinnati facility, the aggregate
cost of which is expected to be less than $4.4 million and which is
the responsibility of the Company. Property and equipment, net in
the condensed balance sheet at March 31, 2014, includes $2.8
million related to certain modifications the Company is making at
Patheon’s Cincinnati facility under the terms of the Capital
Agreement.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">Expenditures associated
with the aforementioned agreements are primarily driven by the
potential commercial requirements and demand for the
Company’s products, none of which have been approved for
commercialization; accordingly, the amounts and timing of such
future expenditures cannot be determined at this time.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 18px"><font style="FONT-FAMILY: Times New Roman" size="2"><i><u>Grünenthal</u></i></font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">On December 16, 2013,
AcelRx and Grünenthal entered into a Collaboration and License
Agreement (the “License Agreement”) and related
Manufacture and Supply Agreement (the “Manufacturing
Agreement” and together with the License Agreement, the
“Grünenthal Agreements”). The License Agreement
grants Grünenthal rights to commercialize Zalviso in the EU,
Switzerland, Liechtenstein, Iceland, Norway and Australia, for pain
treatment within or dispensed by hospitals hospices, nursing homes
and other medically-supervised settings.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">Under the terms of the
Manufacturing Agreement, the Company will manufacture and supply
Zalviso exclusively for Grünenthal. The Company will supply
Zalviso at the Company’s fully burdened manufacturing cost
(as defined in the Manufacturing Agreement). The Manufacturing
Agreement requires the Company to use commercially reasonable
efforts to enter stand-by contracts with third party contract
manufacturers to ensure a continual supply of Zalviso and under
certain conditions permits Grünenthal to use a third party
back-up manufacturer to manufacture Zalviso for commercial sale in
their territories.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">Unless earlier terminated,
the Manufacturing Agreement continues in effect until the later of
the expiration of the obligation of Grünenthal to make royalty
and supply and trademark fee payments or the end of any transition
period for manufacturing obligations due to the expiration or
termination of the License Agreement. The Manufacturing Agreement
is subject to earlier termination in connection with certain
termination events in the License Agreement, in the event the
parties mutually agree, by a party in the event of an uncured
material breach by the other party or upon the bankruptcy or
insolvency of either party.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">Under the Supply Agreement,
the Company will exclusively manufacture and supply Zalviso to
Grünenthal for commercial sale in their
territories.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">Expenditures associated
with the aforementioned agreements are primarily driven by the
potential commercial requirements and demand for the
Company’s products, none of which are currently approved for
commercial use; accordingly, the amounts and timing of such future
expenditures cannot be determined at this time.</font></p>
</div>
<div>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt">
<b><i>The Company</i></b></p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt">
AcelRx Pharmaceuticals, Inc., or the Company or AcelRx, was
incorporated in Delaware on July 13, 2005 as SuRx, Inc., and
in January 2006, the Company changed its name to AcelRx
Pharmaceuticals, Inc. The Company’s operations are based in
Redwood City, California.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt">
AcelRx is a specialty pharmaceutical company focused on the
development and commercialization of innovative therapies for the
treatment of acute and breakthrough pain. AcelRx intends to
commercialize its product candidates in the United States and
license the development and commercialization rights to its product
candidates for sale outside of the United States through strategic
partnerships and collaborations. The Company’s lead product
candidate, Zalviso<sup style="FONT-SIZE: 85%; VERTICAL-ALIGN: top">TM</sup>, formerly known as
the Sufentanil NanoTab patient-controlled analgesia, or PCA,
System, or ARX-01. The New Drug Application, or NDA, for Zalviso is
currently under review by the FDA. The proposed indication for
Zalviso is for the management of moderate-to-severe acute pain in
adult patients in the hospital setting. In addition, in December
2013, the Company entered into a collaboration agreement with
Grünenthal, a European-based pharmaceutical company, for the
commercialization of Zalviso in Europe and Australia. We anticipate
the filing of the Marketing Authorization Application, or MAA, for
Zalviso under the centralized procedure in the European Union, or
EU, in mid-2014.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt">
The Company has incurred recurring operating losses and negative
cash flows from operating activities since inception and expects to
continue to incur negative cash flows until its product candidates
are approved for marketing in the United States and other
countries, in which it has and intends to license its products,
which may never occur. In previous years, prior to the completion
of the clinical development program for Zalviso and the commercial
collaboration of Zalviso, AcelRx was considered a development stage
company.</p>
<p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt">
The Company has one business activity, which is the development and
commercialization of product candidates for the treatment of pain,
and a single reporting and operating unit structure.</p>
</div>
95000
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 18px"><font style="FONT-FAMILY: Times New Roman" size="2"><b>2. Investments and Fair
Value Measurement</b></font></p>
<!-- xbrl,body -->
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Investments</i></b></font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">The Company classifies its
marketable securities as available-for-sale and records its
investments at fair value. Available-for-sale securities are
carried at estimated fair value based on quoted market prices or
observable market inputs of almost identical assets, with the
unrealized holding gains and losses included in accumulated other
comprehensive income. Marketable securities which have maturities
beyond one year as of the end of the reporting period are
classified as non-current.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The table below summarizes
the Company’s cash, cash equivalents and investments (in
thousands):</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="92%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="50%"></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="4%"></td>
<td></td>
<td></td>
<td valign="bottom" width="4%"></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="14" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>As of March 31,
2014</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Amortized Cost</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Gross Unrealized<br />
Gains</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Gross Unrealized<br />
Losses</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Fair<br />
Value</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Cash and cash
equivalents:</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 3em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Cash</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">77,582</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">77,582</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 3em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Money market
funds</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total cash and cash
equivalents</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">77,587</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">77,587</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Marketable
securities:</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 3em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">U.S. government agency securities</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,288</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,289</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total marketable
securities</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,288</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,289</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total cash, cash
equivalents and investments</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">92,875</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">92,876</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
</tr>
<tr>
<td height="16"></td>
<td height="16" colspan="16"></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="14" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>As of December 31,
2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Amortized Cost</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Gross Unrealized<br />
Gains</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Gross Unrealized<br />
Losses</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Fair<br />
Value</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Cash and cash
equivalents:</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 3em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Cash</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">88,390</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">88,390</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 3em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Money market
funds</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">11</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">11</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total cash and cash
equivalents</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">88,401</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">88,401</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Marketable
securities:</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 3em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">U.S. government agency securities</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,261</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,262</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total marketable
securities</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,261</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,262</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total cash, cash
equivalents and investments</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">103,662</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">103,663</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
</tr>
<!-- End Table Body --></table>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">As of March 31, 2014
and December 31, 2013, none of the available-for-sale
securities held by the Company had material unrealized losses.
There were no other-than-temporary impairments for these securities
at March 31, 2014 or December 31, 2013. No gross realized
gains or losses were recognized on the available-for-sale
securities and, accordingly, there were no amounts reclassified out
of accumulated other comprehensive income to earnings during the
three months ended March 31, 2014 and 2013.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">As of March 31, 2014
and December 31, 2013, the contractual maturity of all
investments held was less than one year.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 18px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Fair Value
Measurement</i></b></font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">The Company’s
financial instruments consist of Level I and Level II assets and
Level III liabilities. Level I securities include highly liquid
money market funds and are valued based on quoted market prices.
For Level II instruments, the Company estimates fair value by
utilizing third party pricing services in developing fair value
measurements where fair value is based on valuation methodologies
such as models using observable market inputs, including benchmark
yields, reported trades, broker/dealer quotes, bids, offers and
other reference data. Such Level II instruments typically include
U.S. treasury and U.S. government agency obligations. As of
March 31, 2014 and December 31, 2013, the Company held,
in addition to Level I and Level II assets, a contingent put option
liability associated with the Company’s Amended and Restated
Loan and Security Agreement, or the Amended Loan Agreement, with
Hercules Technology II, L.P. and Hercules Technology Growth
Capital, Inc., collectively referred to as Hercules, which amends
and restates the loan and security agreement with Hercules dated as
of June 29, 2011, or the Original Loan Agreement, and which
was classified as a Level III liability. See Note 5
“Long-Term Debt,” for further description. The
Company’s estimate of fair value of the contingent put option
liability was determined by using a risk-neutral valuation model,
wherein the fair value of the underlying debt facility is estimated
both with and without the presence of the default provisions,
holding all other assumptions constant. The resulting difference
between the two estimated fair values is the estimated fair value
of the default provisions, or the contingent put option. Changes to
the estimated fair value of these liabilities are recorded in
interest income and other income (expense), net in the condensed
statements of comprehensive loss. The fair value of the underlying
debt facility is estimated by calculating the expected cash flows
in consideration of an estimated probability of default and
expected recovery rate in default, and discounting such cash flows
back to the reporting date using a risk-free rate. As of
March 31, 2014 and December 31, 2013, the Company also
held a Level III liability associated with warrants, or PIPE
warrants, issued in connection with the Company’s private
placement equity offering, completed in June 2012. The PIPE
warrants are considered a liability and are valued using the
Black-Scholes option-pricing model, the inputs for which include
exercise price of the PIPE warrants, market price of the underlying
common shares, expected term, volatility based on a group of the
Company’s peers and the risk-free rate corresponding to the
expected term of the PIPE warrants. Changes to any of the inputs
can have a significant impact to the estimated fair value of the
PIPE warrants.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The following table sets
forth the fair value of the Company’s financial assets and
liabilities by level within the fair value hierarchy (in
thousands):</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="92%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="66%"></td>
<td valign="bottom" width="4%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="4%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="4%"></td>
<td></td>
<td></td>
<td></td>
<td valign="bottom" width="2%"></td>
<td></td>
<td></td>
<td valign="bottom" width="2%"></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="14" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>As of March 31,
2014</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Fair Value</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Level I</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Level II</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Level III</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2"><b><u>Assets</u></b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Money market
funds</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">U.S. government agency
obligations</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,289</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,289</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total assets measured at
fair value</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,294</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">5</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,289</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2"><b><u>Liabilities</u></b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">PIPE warrants</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">13,795</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">13,795</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Contingent put option
liability</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">296</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">296</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total liabilities measured
at fair value</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">14,091</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">14,091</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
</tr>
<tr>
<td height="16"></td>
<td height="16" colspan="16"></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="14" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>As of December 31,
2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Fair Value</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Level I</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Level II</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Level III</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2"><b><u>Assets</u></b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Money market
funds</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">11</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">11</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">U.S. government agency
obligations</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,262</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,262</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total assets measured at
fair value</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,273</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">11</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">15,262</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2"><u><b>Liabilities</b></u></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
<td valign="bottom"></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">PIPE warrants</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">13,111</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">13,111</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Contingent put option
liability</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">334</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">334</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Total liabilities measured
at fair value</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">13,445</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" nowrap="nowrap" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">—  </font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">13,445</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
</tr>
<!-- End Table Body --></table>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The following table sets
forth the assumptions used in the Black-Scholes option-pricing
model to estimate the fair value of the PIPE warrants as of
March 31, 2014:</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="89%"></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Market price</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">12.01</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Exercise price</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3.40</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Risk-free interest
rate</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.90</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected
volatility</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">64.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected life (in
years)</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3.7</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected dividend
yield</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<!-- End Table Body --></table>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 12px">
 </p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 0px"><font style="FONT-FAMILY: Times New Roman" size="2">The following table sets
forth the assumptions used in the Black-Scholes option-pricing
model to estimate the fair value of the PIPE warrants as of
December 31, 2013:</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="89%"></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Market price</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">11.31</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Exercise price</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3.40</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Risk-free interest
rate</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1.27</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected
volatility</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">69.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected life (in
years)</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3.92</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected dividend
yield</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<!-- End Table Body --></table>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The following tables set
forth a summary of the changes in the fair value of the
Company’s Level III financial liabilities for the three
months ended March 31, 2014 and March 31, 2013 (in
thousands):</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="84%"></td>
<td valign="bottom" width="10%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three Months<br />
Ended<br />
March 31,<br />
2014</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Fair value—beginning
of period</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">13,445</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Change in fair value of
PIPE warrants</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">684</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Change in fair value of
contingent put option associated with Amended Loan Agreement with
Hercules</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(38</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Fair value—end of
period</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">14,091</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td> </td>
</tr>
<tr>
<td height="16"></td>
<td height="16" colspan="4"></td>
</tr>
<tr>
<td valign="bottom"><font size="1"> </font></td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Three Months<br />
Ended<br />
March 31,<br />
2013</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Fair value—beginning
of period</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">7,500</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Change in fair value of
PIPE warrants</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1,776</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Change in fair value of
contingent put option associated with Original Loan Agreement with
Hercules</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">(22</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">) </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 1px solid"> </p>
</td>
<td> </td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Fair value—end of
period</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">9,254</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr style="FONT-SIZE: 1px">
<td valign="bottom"></td>
<td valign="bottom">  </td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
<td valign="bottom">
<p style="BORDER-TOP: rgb(0,0,0) 3px double"> </p>
</td>
</tr>
</table>
</div>
646000
P2Y
2017-12-31
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">The following table sets
forth the assumptions used in the Black-Scholes option-pricing
model to estimate the fair value of the PIPE warrants as of
March 31, 2014:</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="89%"></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Market price</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">12.01</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Exercise price</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3.40</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Risk-free interest
rate</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.90</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected
volatility</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">64.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected life (in
years)</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3.7</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected dividend
yield</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<!-- End Table Body --></table>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 12px">
 </p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 0px"><font style="FONT-FAMILY: Times New Roman" size="2">The following table sets
forth the assumptions used in the Black-Scholes option-pricing
model to estimate the fair value of the PIPE warrants as of
December 31, 2013:</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="89%"></td>
<td valign="bottom" width="8%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Market price</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">11.31</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Exercise price</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3.40</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Risk-free interest
rate</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">1.27</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected
volatility</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">69.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected life (in
years)</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">3.92</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">Expected dividend
yield</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">0.0</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">% </font></td>
</tr>
</table>
</div>
P18M
0.80
Beyond one year
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 0px"><font style="FONT-FAMILY: Times New Roman" size="2"><b>6.
Warrants</b></font></p>
<!-- xbrl,body -->
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Series A
Warrants</i></b></font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">In March 2007, the Company
entered into an equipment financing agreement in which the Company
issued immediately exercisable and fully vested warrants to
purchase 2,500 shares of its Series A convertible preferred stock,
or the Series A warrants, with an exercise price of $10.00 per
share. The fair value of the Series A warrants on the date of
issuance was $1,000, as determined using the Black-Scholes
option-pricing model. This fair value was recorded as a convertible
preferred stock warrant liability and as a deferred financing cost
in other assets. The fair value was remeasured at the end of each
reporting period. In connection with the IPO, the Series A warrants
were automatically converted into warrants to purchase 3,425 shares
of common stock. As a result of the conversion, these common stock
warrants were no longer recorded as liabilities and were,
therefore, no longer remeasured as of the end of each reporting
period.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">As of March 31, 2014,
warrants to purchase 3,425 shares of common stock had not been
exercised and were still outstanding. These warrants expire in
March 2017.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 18px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Pinnacle
Warrants</i></b></font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">In September 2008, the
Company entered into a $12.0 million loan and security agreement
with Pinnacle Ventures. In connection with this loan and security
agreement, the Company issued immediately exercisable and fully
vested warrants, or the Series B warrants, to purchase 56,250
shares of Series B convertible preferred stock with an exercise
price of $16.00 per share which were ultimately converted into
warrants to purchase 228,264 shares of common stock with an
exercise price of $3.94 per share in connection with the
Company’s initial public offering in 2011.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">In February 2013, warrants
to purchase 228,264 shares were net exercised, for 58,580 shares of
common stock. As of March 31, 2014, no warrants to purchase
shares of common stock issued to Pinnacle were
outstanding.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 18px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>Hercules
Warrants</i></b></font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">In connection with the
Amended Loan Agreement, executed in December 2013, the Company
issued warrants to Hercules which are exercisable for an aggregate
of 176,730 shares of Common Stock and each carry an exercise price
of $6.79 (the “Warrants”). Each Warrant may be
exercised on a cashless basis. The Warrants are exercisable for a
term beginning on the date of issuance and ending on the earlier to
occur of five years from the date of issuance or the consummation
of certain acquisitions of the Company as set forth in the
Warrants. The number of shares for which the Warrants are
exercisable and the associated exercise price are subject to
certain proportional adjustments as set forth in the Warrants. The
Company estimated the fair value of these warrants as of the
issuance date to be $1.1 million, which was recorded as equity. The
fair value of the warrants was calculated using the Black-Scholes
option-valuation model, and was based on the strike price of $6.79,
the stock price at issuance of $9.67, the five-year contractual
term of the warrants, a risk-free interest rate of 1.55%, expected
volatility of 71% and 0% expected dividend yield.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">As of March 31, 2014,
warrants to purchase 176,730 shares of common stock issued to
Hercules had not been exercised and were still outstanding. These
warrants expire in December 2018.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">In connection with the
Original Loan Agreement with Hercules, executed in June 2011, the
Company issued warrants to Hercules to purchase an aggregate of
274,508 shares of common stock at a price of $3.06 per
share.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">During June and July 2013,
warrants to purchase 274,508 shares were net exercised, for 183,404
shares of common stock.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 18px"><font style="FONT-FAMILY: Times New Roman" size="2"><b><i>2012 Private
Placement Warrants</i></b></font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 6px"><font style="FONT-FAMILY: Times New Roman" size="2">In connection with the
Private Placement, completed in June 2012, the Company issued PIPE
warrants to purchase up to 2,630,103 shares of common stock. The
per share exercise price of the PIPE warrants was $3.40 which
equals the closing consolidated bid price of the Company’s
common stock on May 29, 2012, the effective date of the
Purchase Agreement. The PIPE warrants issued in the Private
Placement became exercisable six months after the issuance date,
and expire on the five year anniversary of the initial
exercisability date. Under the terms of the PIPE warrants, upon
certain transactions, including a merger, tender offer, sale of all
or substantially all of the assets of the Company or if a person or
group shall become the owner of 50% of the Company’s issued
and outstanding common stock, which is outside of the
Company’s control, each PIPE warrant holder may elect to
receive a cash payment in exchange for the warrant, in an amount
determined by application of the Black-Scholes option-pricing
model. Accordingly, the PIPE warrants were recorded as a liability
at fair value, as determined by the Black-Scholes option-pricing
model, and then marked to fair value each reporting period, with
changes in estimated fair value recorded through interest income
and other income (expense), net in the condensed statements of
comprehensive loss. The Black-Scholes assumptions used to value the
PIPE warrants are disclosed in Note 2.</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 12px">
 </p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 0px"><font style="FONT-FAMILY: Times New Roman" size="2">Upon execution of the
Purchase Agreement, the fair value of the PIPE warrants was
estimated to be $5.8 million, which was recorded as a liability. As
of March 31, 2014, the fair value of the PIPE warrants was
estimated to be $13.8 million. As of December 31, 2013, the
fair value of the PIPE warrants was estimated to be $13.1 million.
The change in fair value for the three months ended March 31,
2014 and 2013, which was recorded as other expense, was $0.7
million and $1.8 million, respectively.</font></p>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px"><font style="FONT-FAMILY: Times New Roman" size="2">During the three months
ended March 31, 2014, no warrants were exercised for shares of
common stock. As of March 31, 2014, PIPE warrants to purchase
1,494,514 shares of common stock issued in connection with the
Private Placement had not been exercised and were outstanding.
These warrants expire in November 2017.</font></p>
</div>
171500000
560000
2013-01
0.01
0.03
0.02
35961.55
37040.40
28500000
20000000
0.0525
496000
479000
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 0px; TEXT-INDENT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2">Base rent
payable under the Lease Amendment during the Extended Term for the
Current Premises will be as follows:</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="84%"></td>
<td valign="bottom" width="6%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom" nowrap="nowrap">
<p style="BORDER-BOTTOM: rgb(0,0,0) 1px solid; WIDTH: 50pt">
<font style="FONT-FAMILY: Times New Roman" size="1"><b>Period
from/to</b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Monthly Base<br />
Rent</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">May 9, 2016 to
May 8, 2017</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">35,961.55</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">May 9, 2017 to
January 31, 2018</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">37,040.40</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
</table>
</div>
<div>
<p style="MARGIN-BOTTOM: 0px; MARGIN-TOP: 12px; TEXT-INDENT: 4%">
<font style="FONT-FAMILY: Times New Roman" size="2">Base rent
payable under the Lease Amendment for the Expansion Space,
commencing August 1, 2014, will be as follows:</font></p>
<p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 12px; MARGIN-TOP: 0px">
 </p>
<table style="BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0">
<!-- Begin Table Head -->
<tr>
<td width="84%"></td>
<td valign="bottom" width="6%"></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td valign="bottom" nowrap="nowrap">
<p style="BORDER-BOTTOM: rgb(0,0,0) 1px solid; WIDTH: 77pt">
<font style="FONT-FAMILY: Times New Roman" size="1"><b>Months of
Lease Term</b></font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td style="BORDER-BOTTOM: rgb(0,0,0) 1px solid" valign="bottom" colspan="2" align="center"><font style="FONT-FAMILY: Times New Roman" size="1"><b>Monthly Base<br />
Rent</b></font></td>
<td valign="bottom"><font size="1"> </font></td>
</tr>
<!-- End Table Head --><!-- Begin Table Body -->
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">1-12</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2">$</font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">23,001.40</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">13-24</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">23,691.44</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr bgcolor="#CCEEFF">
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">25-36</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">24,402.18</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
<tr>
<td valign="top">
<p style="MARGIN-LEFT: 1em; TEXT-INDENT: -1em"><font style="FONT-FAMILY: Times New Roman" size="2">37-42</font></p>
</td>
<td valign="bottom"><font size="1">  </font></td>
<td valign="bottom"><font style="FONT-FAMILY: Times New Roman" size="2"> </font></td>
<td valign="bottom" align="right"><font style="FONT-FAMILY: Times New Roman" size="2">25,134.25</font></td>
<td valign="bottom" nowrap="nowrap"><font style="FONT-FAMILY: Times New Roman" size="2">  </font></td>
</tr>
</table>
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16.00
56250
3.94
228264
2017-03-01
0.01
P1Y
0.03
-38000
700000
3425
5083428
1674669
6.79
Subject to certain conditions and limitations set forth in the Loan Agreement, the Company has the right to convert up to $5.0 million of scheduled principal installments under the Notes into freely tradeable shares of the Company’s common stock (“Common Stock”). The number of shares of Common Stock that would be issued upon conversion of the Notes would be equal to the number determined by dividing (x) the product of (A) the principal amount to be paid in shares of Common Stock and (B) 103%, by (y) $9.30 (subject to certain proportional adjustments as provided for in the Loan Agreement).
128000
472000
1700000
If the Company prepays the loan prior to maturity, it will pay the Lenders a prepayment charge, based on a percentage of the then outstanding principal balance, equal to 3% if the prepayment occurs prior to December 16, 2014, 2% if the prepayment occurs after December 16, 2014, but prior to December 16, 2015, or 1% if the prepayment occurs after December 16, 2015.
0.05
3.06
274508
P7Y
Payments under the Loan Agreement are interest only until April 1, 2015 (which will be extended until January 1, 2016 if the Company achieves the Milestone on or before April 1, 2015) followed by equal monthly payments of principal and interest through the scheduled maturity date on October 1, 2017 (which would be extended until January 1, 2018 if the Company achieves the Milestone on or prior to April 1, 2015) (the "Loan Maturity Date").
684000
0.640
0.000
0.0090
P3Y8M12D
Under the terms of the PIPE warrants, upon certain transactions, including a merger, tender offer, sale of all or substantially all of the assets of the Company or if a person or group shall become the owner of 50% of the Company's issued and outstanding common stock, which is outside of the Company's control, each PIPE warrant holder may elect to receive a cash payment in exchange for the warrant, in an amount determined by application of the Black-Scholes option-pricing model.
P6M
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The condensed balance sheet as of December 31, 2013 has been derived from the audited financial statements as of that date included in the Company's Annual Report on Form 10-K for the year ended December 31, 2013.