

<!-- RR Donnelley Xcelerate Instance Document, based on XBRL 2.1  http://www.rrdonnelley.com/ -->
<!-- Version:  6.21.0 -->
<!-- Round: 6 -->
<!-- Creation date: 2014-08-13T05:43:27Z -->
<!-- Copyright (c) 2005-2013 R.R. Donnelley & Sons Company All Rights Reserved. -->
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 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;6. Stock-Based Awards&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt"&gt;
 &lt;b&gt;Stock Option Plans&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The Company&amp;#x2019;s Amended and Restated 2006 Stock Option Plan
 (the &amp;#x201C;2006 Plan&amp;#x201D;) provided for the Company to sell or
 issue common stock or restricted common stock, or to grant
 incentive stock options or nonqualified stock options for the
 purchase of common stock, to employees, members of the board of
 directors and consultants of the Company. The 2006 Plan is
 administered by the board of directors, or at the discretion of the
 board of directors, by a committee of the board. The exercise
 prices, vesting and other restrictions are determined at the
 discretion of the board of directors, or their committee if so
 delegated, except that the exercise price per share of stock
 options may not be less than 100% of the fair market value of the
 share of common stock on the date of grant and the term of stock
 option may not be greater than ten years. The total number of
 shares of common stock that could be issued under the 2006 Plan was
 1,889,150 shares. Upon closing of the Company&amp;#x2019;s IPO, 168,221
 shares reserved and not then subject to outstanding options were
 transferred to the 2014 Stock Option and Incentive Plan, and no
 further awards will be made under the 2006 Plan.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 On June&amp;#xA0;5, 2014, the Company&amp;#x2019;s stockholders approved the
 2014 Stock Option and Incentive Plan (the &amp;#x201C;2014 Stock Option
 Plan&amp;#x201D;), which became effective upon the completion of the IPO
 of the Company&amp;#x2019;s shares of common stock in June 2014. The
 2014 Stock Option Plan provides for the grant of stock options,
 stock appreciation rights, restricted stock, restricted stock
 units, unrestricted stock, performance-share awards and cash-based
 awards. The number of shares initially reserved for issuance under
 the 2014 Stock Option Plan is 2,168,221&amp;#xA0;shares of common stock
 and may be increased by the number of shares under the 2006 Plan
 that are not needed to fulfill the Company&amp;#x2019;s obligations for
 awards issued under the 2006 Plan as a result of forfeiture,
 expiration, cancellation, termination or net issuances of awards
 thereunder. The number of shares of common stock that may be issued
 under the plan is also subject to increase on the first day of each
 fiscal year by the lesser of (i)&amp;#xA0;4% of the Company&amp;#x2019;s
 outstanding shares of common stock as of that date, or (ii)&amp;#xA0;an
 amount determined by the board of directors.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company generally grants stock-based awards with service
 conditions only (&amp;#x201C;service-based&amp;#x201D; awards).&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 As required by the 2006 Plan and 2014 Stock Option Plan, the
 exercise price for stock options granted is not to be less than the
 fair value of common shares as of the date of grant. Prior to the
 IPO, the value of common stock was determined by the board of
 directors by taking into consideration its most recently available
 valuation of common shares performed by management and the board of
 directors as well as additional factors which might have changed
 since the date of the most recent contemporaneous valuation through
 the date of grant.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 For the three months ended June&amp;#xA0;30, 2014, the Company granted
 326,542 stock options, 324,950 stock options to employees and 1,592
 stock options to a consultant.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;2014 Employee Stock Purchase Plan&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 On June&amp;#xA0;5, 2014, the Company&amp;#x2019;s stockholders approved the
 2014 Employee Stock Purchase Plan. A total of 265,000&amp;#xA0;shares
 of common stock were reserved for issuance under this plan. The
 2014 Employee Stock Purchase Plan became effective upon the
 completion of the IPO of the Company&amp;#x2019;s shares of common
 stock. No offering periods have commenced as of June&amp;#xA0;30,
 2014.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Stock Option Valuation&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The fair value of each stock option grant is estimated on the date
 of grant using the Black-Scholes option-pricing model. The Company
 historically has been a private company and lacks company-specific
 historical and implied volatility information. Therefore, it
 estimates its expected stock volatility based on the historical
 volatility of a publicly traded set of peer companies and expects
 to continue to do so until such time as it has adequate historical
 data regarding the volatility of its own traded stock price. The
 expected term of the Company&amp;#x2019;s stock options has been
 determined utilizing the &amp;#x201C;simplified&amp;#x201D; method for awards
 that qualify as &amp;#x201C;plain-vanilla&amp;#x201D; options. The expected
 term of stock options granted to nonemployees is equal to the
 contractual term of the option award. The risk-free interest rate
 is determined by reference to the U.S.&amp;#xA0;Treasury yield curve in
 effect at the time of grant of the award for time periods
 approximately equal to the expected term of the award. Expected
 dividend yield is based on the fact that the Company has never paid
 cash dividends and does not expect to pay any cash dividends in the
 foreseeable future. The assumptions that the Company used to
 determine the fair value of the stock options granted to employees
 and directors are as follows, presented on a weighted average
 basis:&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 As of June&amp;#xA0;30, 2014, there were outstanding unvested
 service-based stock options held by nonemployees for the purchase
 of 17,513 shares of common stock. Additionally as of June&amp;#xA0;30,
 2014, there were outstanding unvested performance-based stock
 options held by nonemployees for the purchase of 796 shares of
 common stock.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 18px"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt"&gt;
 &lt;b&gt;Stock-based Compensation&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The Company recorded stock-based compensation expense related to
 stock options and restricted common stock in the following expense
 categories of its statements of operations:&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="92%" align="center" border="0"&gt;
 &lt;tr&gt;
 &lt;td width="76%"&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="3%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="3%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="3%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="3%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"&gt;&lt;b&gt;Three&amp;#xA0;Months&amp;#xA0;Ended&lt;br /&gt;
 June&amp;#xA0;30,&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"&gt;&lt;b&gt;Six&amp;#xA0;Months&amp;#xA0;Ended&lt;br /&gt;
 June&amp;#xA0;30,&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;2014&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;2013&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;2014&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;2013&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Research and development&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;99&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;43&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;168&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;69&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 General and administrative&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;169&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;60&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;276&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;84&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;268&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;103&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;444&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;153&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 As of June&amp;#xA0;30, 2014, the Company had an aggregate of $2,798 of
 unrecognized stock-based compensation cost, which is expected to be
 recognized over a weighted average period of 3.6 years.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock>
  <us-gaap:NewAccountingPronouncementsPolicyPolicyTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_72774B67-C035-4E37-A9BF-7CBF65DFA4B6_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Recently Issued and Adopted Accounting Pronouncements&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 In June 2014, the FASB issued Accounting Standards Update
 No.&amp;#xA0;2014-10, Development Stage Entities (Topic 915):
 Elimination of Certain Financial Reporting Requirements, Including
 an Amendment to Variable Interest Entities Guidance in Topic 810,
 Consolidation. The amendments in this guidance remove all
 incremental financial reporting requirements for development stage
 entities.&amp;#xA0;Among other changes, this guidance will no longer
 require development stage entities to present inception-to-date
 information about income statement line items, cash flows, and
 equity transactions. This guidance is effective for public
 companies in the first annual period beginning after
 December&amp;#xA0;15, 2014.&amp;#xA0;Early application is permitted for
 interim and annual periods for which financial statements have not
 yet been issued. The Company elected to apply this disclosure
 guidance to its consolidated financial statements for the three
 months ended June&amp;#xA0;30, 2014 and as a result, no longer
 discloses inception-to-date information in its Consolidated
 Statements of Operations and Comprehensive Loss, Cash Flows and
 Stockholders&amp;#x2019; Deficit and the related notes thereto.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:NewAccountingPronouncementsPolicyPolicyTextBlock>
  <us-gaap:ShareBasedCompensationOptionAndIncentivePlansPolicy contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_EB2A228C-6761-486C-BB0E-92ED01668231_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Accounting for Stock-Based Compensation&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The Company measures all stock options and other stock-based awards
 granted to employees and directors at the fair value on the date of
 the grant using the Black-Scholes option-pricing model. The fair
 value of the awards is recognized as expense, net of estimated
 forfeitures, over the requisite service period, which is generally
 the vesting period of the respective award. The straight-line
 method of expense recognition is applied to all awards with
 service-only conditions.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 For stock-based awards granted to consultants and nonemployees,
 compensation expense is recognized over the period during which
 services are rendered by such consultants and nonemployees until
 completed. At the end of each financial reporting period prior to
 completion of the service, the fair value of these awards is
 re-measured using the then-current fair value of the
 Company&amp;#x2019;s common stock and updated assumption inputs in the
 Black-Scholes option-pricing model.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company classifies stock-based compensation expense in its
 consolidated statement of operations and comprehensive loss in the
 same manner in which the award recipient&amp;#x2019;s payroll costs are
 classified or in which the award recipients&amp;#x2019; service payments
 are classified.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company recognizes compensation expense for only the portion of
 awards that are expected to vest. In developing a forfeiture rate
 estimate, the Company has considered its historical experience to
 estimate pre-vesting forfeitures for service-based awards. The
 impact of a forfeiture rate adjustment will be recognized in full
 in the period of adjustment, and if the actual forfeiture rate is
 materially different from the Company&amp;#x2019;s estimate, the Company
 may be required to record adjustments to stock-based compensation
 expense in future periods.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:ShareBasedCompensationOptionAndIncentivePlansPolicy>
  <us-gaap:CommitmentsAndContingenciesDisclosureTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_BC063736-1E56-4216-BA8C-A70BF04A3C0F_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;7. Commitments and Contingencies&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt"&gt;
 &lt;b&gt;Leases&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The Company leases its office space under an operating lease
 agreement that initially expired on July&amp;#xA0;31, 2013, but was
 amended to extend the lease through July&amp;#xA0;31, 2014.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 On May&amp;#xA0;15, 2014, the Company entered into new lease of office
 space in Boston, Massachusetts, effective as of July&amp;#xA0;28, 2014,
 with a term expiring July&amp;#xA0;31, 2017 and an option to extend the
 lease for three additional years.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 Future minimum lease payments for its operating leases as of
 June&amp;#xA0;30, 2014, are as follows:&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0"&gt;
 &lt;tr&gt;
 &lt;td width="91%"&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="6%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;
 &lt;p style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman; BORDER-BOTTOM: #000000 1pt solid; WIDTH: 92.45pt"&gt;
 &lt;b&gt;Year Ending December&amp;#xA0;31,&lt;/b&gt;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" colspan="2"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 2014&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;106&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 2015&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;229&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 2016&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;235&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 2017&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;139&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Total&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;709&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 During the three months ended June&amp;#xA0;30, 2014 and 2013, the
 Company recognized $27 and $32, respectively, of rental expense
 related to office space. During the six months ended June&amp;#xA0;30,
 2014 and 2013, the Company recognized $52 and $64, respectively, of
 rental expense related to office space.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Intellectual Property Licenses&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The Company has acquired exclusive rights to develop patented
 compounds and related know-how for beloranib under two licensing
 agreements with two third parties in the course of its research and
 development activities. The licensing rights obligate the Company
 to make payments to the licensors for license fees, milestones,
 license maintenance fees and royalties. The Company is also
 responsible for patent prosecution costs.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 As of June&amp;#xA0;30, 2014, the Company is obligated to make
 milestone payments of up to $18,950 upon reaching certain
 pre-commercialization milestones, such as clinical trials and
 government approvals, and up to $12,500 upon reaching certain
 product commercialization milestones. Under one of the license
 agreements, the Company is also obligated to pay up to $1,250 with
 respect to each subsequent licensed product, if any, that is a new
 chemical entity. In addition, the Company will owe single-digit
 royalties on sales of commercial products developed using these
 licensed technologies, if any. The Company is also obligated to pay
 to the licensors a percentage of fees received if and when the
 Company sublicenses the technology. As of June&amp;#xA0;30, 2014, the
 Company has not yet developed a commercial product using the
 licensed technologies and it has not entered into any sublicense
 agreements for the technologies. The Company reasonably anticipates
 that it may be required to pay $6,700 of milestone payments in
 2014, provided various development milestones are achieved.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Indemnification Agreements&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 In the ordinary course of business, the Company may provide
 indemnification of varying scope and terms to vendors, lessors,
 business partners, and other parties with respect to certain
 matters including, but not limited to, losses arising out of breach
 of such agreements or from intellectual property infringement
 claims made by third parties. In addition, the Company has entered
 into indemnification agreements with members of its board of
 directors that will require the Company, among other things, to
 indemnify them against certain liabilities that may arise by reason
 of their status or service as directors or officers. The maximum
 potential amount of future payments the Company could be required
 to make under these indemnification agreements is, in many cases,
 unlimited. To date, the Company has not incurred any material costs
 as a result of such indemnifications. The Company does not believe
 that the outcome of any claims under indemnification arrangements
 will have a material effect on its financial position, results of
 operations or cash flows, and it has not accrued any liabilities
 related to such obligations in its consolidated financial
 statements as of June&amp;#xA0;30, 2014.&lt;/p&gt;
 
 
 &lt;/div&gt;</us-gaap:CommitmentsAndContingenciesDisclosureTextBlock>
  <us-gaap:FairValueMeasurementPolicyPolicyTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_66C0B195-391D-4852-A66F-5C1C6D5B1913_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Fair Value Measurements&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Certain assets and liabilities are carried at fair value under
 GAAP. Fair value is defined as the exchange price that would be
 received for an asset or paid to transfer a liability (an exit
 price) in the principal or most advantageous market for the asset
 or liability in an orderly transaction between market participants
 on the measurement date. Valuation techniques used to measure fair
 value must maximize the use of observable inputs and minimize the
 use of unobservable inputs. Financial assets and liabilities
 carried at fair value are to be classified and disclosed in one of
 the following three levels of the fair value hierarchy, of which
 the first two are considered observable and the last is considered
 unobservable:&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="100%" border="0"&gt;
 &lt;tr&gt;
 &lt;td width="5%"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="top" width="2%" align="left"&gt;&amp;#x2022;&lt;/td&gt;
 &lt;td valign="top" width="1%"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="top" align="left"&gt;Level 1&amp;#x2014;Quoted prices in active
 markets for identical assets or liabilities.&lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 &lt;p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 12px"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="100%" border="0"&gt;
 &lt;tr&gt;
 &lt;td width="5%"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="top" width="2%" align="left"&gt;&amp;#x2022;&lt;/td&gt;
 &lt;td valign="top" width="1%"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="top" align="left"&gt;Level 2&amp;#x2014;Observable inputs
 (other than Level 1 quoted prices) such as quoted prices in active
 markets for similar assets or liabilities, quoted prices in markets
 that are not active for identical or similar assets or liabilities,
 or other inputs that are observable or can be corroborated by
 observable market data.&lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 6pt; MARGIN-TOP: 0pt"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="100%" border="0"&gt;
 &lt;tr&gt;
 &lt;td width="5%"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="top" width="2%" align="left"&gt;&amp;#x2022;&lt;/td&gt;
 &lt;td valign="top" width="1%"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="top" align="left"&gt;Level 3&amp;#x2014;Unobservable inputs
 that are supported by little or no market activity and that are
 significant to determining the fair value of the assets or
 liabilities, including pricing models, discounted cash flow
 methodologies and similar techniques.&lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company&amp;#x2019;s cash equivalents of $120,000 and $26,501 as of
 June&amp;#xA0;30, 2014 and December&amp;#xA0;31, 2013, respectively, were
 carried at fair value based on quoted prices in active markets, a
 Level 1 measurement. The carrying values of accounts payable and
 accrued expenses approximate their fair value due to the short-term
 nature of these liabilities. The Company&amp;#x2019;s carrying value of
 outstanding debt issued in the first quarter of 2014 approximates
 fair value based on the recent execution date of the credit
 facility agreement, and is considered a Level 2 measurement.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:FairValueMeasurementPolicyPolicyTextBlock>
  <us-gaap:ComprehensiveIncomePolicyPolicyTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_78991431-D503-44E9-A4CE-2CF43A29C26F_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt"&gt;
 &lt;b&gt;Comprehensive Loss&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Comprehensive loss includes net loss as well as other changes in
 stockholders&amp;#x2019; equity (deficit) that result from transactions
 and economic events other than those with stockholders. For the
 three and six months ended June&amp;#xA0;30, 2014 and 2013, there was
 no difference between net loss and comprehensive loss.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:ComprehensiveIncomePolicyPolicyTextBlock>
  <us-gaap:StockholdersEquityReverseStockSplit contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_39BED8B8-588D-43EC-80E9-DA5715380CFA_1_0">Company effected a 1-for-6.28 reverse stock split of its issued and outstanding shares of common stock and a proportional adjustment to the existing conversion ratios for each series of redeemable convertible preferred stock.</us-gaap:StockholdersEquityReverseStockSplit>
  <us-gaap:IntangibleAssetsFiniteLivedPolicy contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_83796838-E9A9-485E-B787-0ECCB6F0A047_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt"&gt;
 &lt;b&gt;Patent Costs&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 All patent-related costs incurred in connection with filing and
 prosecuting patent applications are recorded as general and
 administrative expenses as incurred, as recoverability of such
 expenditures is uncertain.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:IntangibleAssetsFiniteLivedPolicy>
  <us-gaap:ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_83B4277F-E156-4131-A667-6568A2B1CDDB_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The following common stock equivalents outstanding as of
 June&amp;#xA0;30, 2014 and 2013, were excluded from the computation of
 diluted net loss per share for the three and six months ended
 June&amp;#xA0;30, 2014 and 2013, because they had an anti-dilutive
 impact:&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="76%" align="center" border="0"&gt;&lt;!-- Begin Table Head --&gt;
 &lt;tr&gt;
 &lt;td width="75%"&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="3%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="3%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: rgb(0,0,0) 1pt solid" valign="bottom" colspan="6" align="center"&gt;&lt;b&gt;As of June&amp;#xA0;30,&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: rgb(0,0,0) 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;2014&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: rgb(0,0,0) 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;2013&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;!-- End Table Head --&gt;&lt;!-- Begin Table Body --&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Options to purchase common stock&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;1,839,895&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;1,283,264&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Redeemable convertible preferred stock&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap" align="right"&gt;&amp;#x2014;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;78,372,931&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: rgb(0,0,0) 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: rgb(0,0,0) 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: rgb(0,0,0) 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: rgb(0,0,0) 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Total options and redeemable convertible preferred stock
 exercisable or convertible into common stock&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;1,839,895&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;79,656,195&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: rgb(0,0,0) 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: rgb(0,0,0) 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: rgb(0,0,0) 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: rgb(0,0,0) 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 
 
 &lt;/div&gt;</us-gaap:ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock>
  <us-gaap:LineOfCreditFacilityDescription contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_0DCA78F6-5772-44B8-B2E3-1913E1DB10E0_1_0">The Company was obligated to make monthly, interest-only payments on any term loans funded under the Credit Facility until December 1, 2014 and, thereafter, to pay 36 consecutive, equal monthly installments of principal and interest from January 1, 2015 through December 1, 2017. As per the terms of the agreement, in June 2014, upon the completion of the Company&#x2019;s IPO, the term of monthly, interest-only payments has been extended until June 1, 2015.</us-gaap:LineOfCreditFacilityDescription>
  <us-gaap:DebtDisclosureTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_89E8FCA3-0318-4984-A922-E947E8D202E9_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;4. Notes Payable&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 On March&amp;#xA0;31, 2014, the Company entered into a loan and
 security agreement with Oxford Finance LLC and Midcap Financial
 (the &amp;#x201C;Credit Facility&amp;#x201D;). The Credit Facility provides
 for initial borrowings of $7,500 under a term loan (&amp;#x201C;Term
 Loan A&amp;#x201D;) and additional borrowings of up to $12,500 under
 other term loans, for a maximum of $20,000. On March&amp;#xA0;31, 2014,
 the Company received proceeds of $7,500 from the issuance of
 promissory notes under the Term Loan A. Of the additional $12,500
 amount that is available, $7,500 (&amp;#x201C;Term Loan B&amp;#x201D;) is
 available to be drawn down until September&amp;#xA0;30, 2014 and $5,000
 (&amp;#x201C;Term Loan C&amp;#x201D;) was available to be drawn down for a
 30-day period upon the completion of the Company&amp;#x2019;s IPO that
 occurred in June 2014. The Company elected not to draw down Term
 Loan C and this amount is no longer available to the Company. All
 promissory notes issued under the Credit Facility are
 collateralized by substantially all of the Company&amp;#x2019;s personal
 property, other than its intellectual property.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 Upon entering into this Credit Facility, the Company was obligated
 to make monthly, interest-only payments on any term loans funded
 under the Credit Facility until December&amp;#xA0;1, 2014 and,
 thereafter, to pay 36 consecutive, equal monthly installments of
 principal and interest from January&amp;#xA0;1, 2015 through
 December&amp;#xA0;1, 2017. As per the terms of the agreement, in June
 2014, upon the completion of the Company&amp;#x2019;s IPO, the term of
 monthly, interest-only payments has been extended until
 June&amp;#xA0;1, 2015. Outstanding term loans under the Credit Facility
 bear interest at an annual rate of 8.1%. In addition, a final
 payment equal to 6.0% of any amounts drawn under the Credit
 Facility is due upon the earlier of the maturity date, acceleration
 of the term loans or prepayment of all or part of the term loans.
 The Company accrues the amount due relating to Term Loan A of $450,
 to outstanding debt by charges to interest expense using the
 effective-interest method from the date of issuance through the
 maturity date.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 Term Loan A was recorded in the balance sheet net of debt discount
 of $114 that was related to fees assessed by the lender at the time
 of borrowing. The debt discount is being accreted to the principal
 amount of the debt. In addition, deferred financing costs of $49
 are being amortized to interest expense using the
 effective-interest method over the same term. For both the three
 and six months ended June&amp;#xA0;30, 2014, the Company recorded
 additional interest expense of $19 related the accretion of the
 debt discount and amortization of deferred financing costs.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company is obligated to pay a separate fee upon any IPO; a sale
 of substantially all of the Company&amp;#x2019;s assets; or a merger,
 reorganization or sale of the Company&amp;#x2019;s voting equity
 securities where existing voting stockholders hold less than 50% of
 voting equity securities after such transaction. As of
 June&amp;#xA0;30, 2014, the Company recorded additional interest
 expense of $225 relating to the accrual of the fee payable upon the
 Company&amp;#x2019;s IPO.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 There are no financial covenants associated with the debt facility;
 however, there are negative covenants restricting the
 Company&amp;#x2019;s activities, including limitations on dispositions,
 mergers or acquisitions; encumbering or granting a security
 interest in its intellectual property; incurring indebtedness or
 liens; paying dividends; making certain investments; and certain
 other business transactions.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 12px"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt; TEXT-INDENT: 4%"&gt;
 The Credit Facility also includes events of default, the occurrence
 and continuation of any of which provides the lenders the right to
 exercise remedies against the Company and the collateral securing
 the loans under the Credit Facility, including cash. These events
 of default include, among other things, failure to pay any amounts
 due under the Credit Facility, insolvency, the occurrence of a
 material adverse event, the occurrence of any default under certain
 other indebtedness and a final judgment against the Company in an
 amount greater than $250.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 Estimated future principal payments due under the Term Loan A are
 as follows:&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0"&gt;
 &lt;tr&gt;
 &lt;td width="89%"&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="6%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;
 &lt;p style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman; BORDER-BOTTOM: #000000 1pt solid; WIDTH: 95.55pt"&gt;
 &lt;b&gt;Years Ending December&amp;#xA0;31,&lt;/b&gt;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" colspan="2"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 2014&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap" align="right"&gt;
 &amp;#x2014;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 2015&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;1,381&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 2016&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;2,936&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 2017&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;3,183&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em"&gt;
 Total&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;7,500&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 During the three and six months ended June&amp;#xA0;30, 2014, the
 Company recognized $443 and $445, respectively, of interest expense
 related to the Credit Facility.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company had no debt outstanding as of December&amp;#xA0;31,
 2013.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:DebtDisclosureTextBlock>
  <us-gaap:ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_A576C281-685C-4FF2-A6A0-2E5847EDBA35_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 Future minimum lease payments for its operating leases as of
 June&amp;#xA0;30, 2014 are as follows:&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0"&gt;
 &lt;tr&gt;
 &lt;td width="91%"&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="6%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;
 &lt;p style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman; BORDER-BOTTOM: #000000 1pt solid; WIDTH: 92.45pt"&gt;
 &lt;b&gt;Year Ending December&amp;#xA0;31,&lt;/b&gt;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" colspan="2"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 2014&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;106&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 2015&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;229&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 2016&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;235&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 2017&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;139&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Total&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;709&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 &lt;/div&gt;</us-gaap:ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock>
  <us-gaap:ScheduleOfAccruedLiabilitiesTableTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_4B2FA92B-5782-4526-99BF-4A86A93352FB_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Accrued expenses consisted of the following:&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="76%" align="center" border="0"&gt;
 &lt;tr&gt;
 &lt;td width="76%"&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="8%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="8%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;June&amp;#xA0;30,&lt;br /&gt;
 2014&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;December&amp;#xA0;31,&lt;br /&gt;
 2013&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Accrued payroll and related expenses&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;465&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;49&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Accrued research and development expenses&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;592&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;616&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Accrued professional fees&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;657&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;196&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Accrued interest expense&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;266&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap" align="right"&gt;
 &amp;#x2014;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Accrued other&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;65&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;39&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;2,045&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;900&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 &lt;/div&gt;</us-gaap:ScheduleOfAccruedLiabilitiesTableTextBlock>
  <us-gaap:ScheduleOfMaturitiesOfLongTermDebtTableTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_38EC21A1-784D-4449-BB5E-D293876D7573_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 Estimated future principal payments due under the Term Loan A are
 as follows:&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="68%" align="center" border="0"&gt;
 &lt;tr&gt;
 &lt;td width="89%"&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="6%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;
 &lt;p style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman; BORDER-BOTTOM: #000000 1pt solid; WIDTH: 95.55pt"&gt;
 &lt;b&gt;Years Ending December&amp;#xA0;31,&lt;/b&gt;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" colspan="2"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 2014&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap" align="right"&gt;
 &amp;#x2014;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 2015&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;1,381&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 2016&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;2,936&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 2017&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;3,183&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 3em; TEXT-INDENT: -1em"&gt;
 Total&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;7,500&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 
 
 &lt;/div&gt;</us-gaap:ScheduleOfMaturitiesOfLongTermDebtTableTextBlock>
  <us-gaap:AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_07ED26BE-BBC2-4933-82A7-2F9318F6AAAA_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt"&gt;
 &lt;b&gt;3. Accrued Expenses&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Accrued expenses consisted of the following:&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="76%" align="center" border="0"&gt;
 &lt;tr&gt;
 &lt;td width="76%"&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="8%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="8%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;June&amp;#xA0;30,&lt;br /&gt;
 2014&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;December&amp;#xA0;31,&lt;br /&gt;
 2013&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Accrued payroll and related expenses&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;465&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;49&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Accrued research and development expenses&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;592&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;616&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Accrued professional fees&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;657&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;196&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Accrued interest expense&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;266&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap" align="right"&gt;
 &amp;#x2014;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Accrued other&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;65&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;39&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;2,045&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;900&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 &lt;/div&gt;</us-gaap:AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock>
  <us-gaap:WeightedAverageNumberOfShareOutstandingBasicAndDiluted contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" decimals="0" id="id_5987172_22944915-D338-4DEA-8A11-3FD0FE0F87E4_3_15" unitRef="shares">1457931</us-gaap:WeightedAverageNumberOfShareOutstandingBasicAndDiluted>
  <us-gaap:StockholdersEquityNoteDisclosureTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_ADDB730F-C929-45EF-8239-813925394641_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;5. Stockholders&amp;#x2019; Equity&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 On June&amp;#xA0;5, 2014, the Company effected a 1-for-6.28 reverse
 stock split of its issued and outstanding shares of common stock
 and a proportional adjustment to the existing conversion ratios for
 each series of redeemable convertible preferred stock. Accordingly,
 all share and per share amounts for all periods presented in these
 consolidated financial statements and notes thereto have been
 adjusted retroactively, where applicable, to reflect this reverse
 stock split and adjustment of the redeemable convertible preferred
 stock conversion ratios.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 On June&amp;#xA0;24, 2014 the Company completed an IPO of its common
 stock, which resulted in the sale of 6,900,000 shares at a price of
 $16.00 per share. The Company received net proceeds from the IPO of
 approximately $102,672 based upon the price of $16.00 per share and
 after deducting underwriting discounts and commissions paid by the
 Company. The Company also incurred offering costs of $2,508 related
 to the IPO.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 Upon closing of the IPO, all outstanding shares of the
 Company&amp;#x2019;s redeemable convertible preferred stock were
 converted into 15,077,621 shares of common stock.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 As of June&amp;#xA0;30, 2014 the Company&amp;#x2019;s Certificate of
 Incorporation, as amended and restated, authorizes the Company to
 issue 5,000,000 shares of $0.001 par value preferred stock.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 As of June&amp;#xA0;30, 2014 and December&amp;#xA0;31, 2013, the
 Company&amp;#x2019;s Certificate of Incorporation, as amended and
 restated, authorizes the Company to issue 115,000,000 shares of
 $0.001 par value common stock.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 During the six months ended June&amp;#xA0;30, 2013, the Company
 reacquired and retired 6,635 shares of restricted common stock, at
 cost, that were forfeited by a former employee.&lt;/p&gt;
 
 
 &lt;/div&gt;</us-gaap:StockholdersEquityNoteDisclosureTextBlock>
  <us-gaap:NetCashProvidedByUsedInOperatingActivitiesContinuingOperations contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" decimals="-3" id="id_5987172_329D4BCA-3DFA-46BA-924E-EC73F0E817E8_1_12" unitRef="iso4217_USD">-10249000</us-gaap:NetCashProvidedByUsedInOperatingActivitiesContinuingOperations>
  <us-gaap:DefinedContributionPlanEmployerMatchingContributionPercent contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" decimals="2" id="id_5987172_33DAC31D-CAC8-4C11-B730-F0290E99D4E4_1_0" unitRef="pure">0.02</us-gaap:DefinedContributionPlanEmployerMatchingContributionPercent>
  <us-gaap:DeferredChargesPolicyTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_3EE60404-CE80-4137-BEBA-CFF3FBCFA5FE_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Deferred Offering Costs&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The Company capitalizes certain legal, accounting and other
 third-party fees that are directly associated with in-process
 equity financings as other assets until such financings are
 consummated. After consummation of the equity financing, these
 costs are recorded in stockholders&amp;#x2019; equity (deficit) as a
 reduction of additional paid-in capital generated as a result of
 the offering or as a reduction to the carrying value of preferred
 stock issued. As of December&amp;#xA0;31, 2013, the Company had
 recorded $743 of deferred offering costs, included in other assets
 in the accompanying consolidated balance sheet in contemplation of
 the Company&amp;#x2019;s IPO of its common stock which closed in June
 2014. The Company has no deferred offering costs as of
 June&amp;#xA0;30, 2014.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:DeferredChargesPolicyTextBlock>
  <us-gaap:PropertyPlantAndEquipmentUsefulLife contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_02FB836A-54D3-42F9-8663-A3D8884F6EEA_1_0">P5Y</us-gaap:PropertyPlantAndEquipmentUsefulLife>
  <us-gaap:PropertyPlantAndEquipmentPolicyTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_1B4EAA2E-5C16-4F5F-83C4-DCAD51716A60_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Property and Equipment&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Property and equipment are stated at cost less accumulated
 depreciation. Depreciation expense is recognized using the
 straight-line method over a five-year estimated useful life for
 both furniture and fixtures and office equipment. Expenditures for
 repairs and maintenance of assets are charged to expense as
 incurred. Upon retirement or sale, the cost and related accumulated
 depreciation of assets disposed of are removed from the accounts
 and any resulting gain or loss is included in loss from
 operations.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:PropertyPlantAndEquipmentPolicyTextBlock>
  <us-gaap:CashAndCashEquivalentsPolicyTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_DE7B6508-1D22-420A-A3AE-5637BD50B7D8_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Cash Equivalents&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The Company considers all short-term, highly liquid investments
 with original maturities of ninety days or less at acquisition date
 to be cash equivalents. Cash equivalents, which consist of money
 market accounts, are stated at fair value.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:CashAndCashEquivalentsPolicyTextBlock>
  <us-gaap:EarningsPerShareBasicAndDiluted contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" decimals="2" id="id_5987172_22944915-D338-4DEA-8A11-3FD0FE0F87E4_3_14" unitRef="iso4217_USD_per_shares">-7.51</us-gaap:EarningsPerShareBasicAndDiluted>
  <us-gaap:BusinessDescriptionAndBasisOfPresentationTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_61391D04-77F8-49F1-B2BA-E6F4A2C2B3BA_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt"&gt;
 &lt;b&gt;1. Nature of the Business and Basis of Presentation&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Zafgen, Inc. (the &amp;#x201C;Company&amp;#x201D;) was incorporated on
 November&amp;#xA0;22, 2005 under the laws of the State of Delaware. The
 Company is a biopharmaceutical company dedicated to significantly
 improving the health and well-being of patients affected by
 obesity. Beloranib, the Company&amp;#x2019;s lead product candidate, is
 a novel, first-in-class, twice-weekly subcutaneous injection being
 developed for the treatment of multiple indications, including
 obesity and hyperphagia in Prader-Willi syndrome patients,
 hypothalamic injury-associated obesity including
 craniopharyngioma-associated obesity, and severe obesity in the
 general population. Since its inception, the Company has devoted
 substantially all of its efforts to research and development,
 recruiting management, acquiring operating assets and raising
 capital.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company was previously classified as a &amp;#x201C;development stage
 entity&amp;#x201D; in the Accounting Standards Codification and, as
 such, was required to present inception-to-date information in the
 Company&amp;#x2019;s consolidated statements of operations and
 comprehensive loss, redeemable convertible preferred stock and
 stockholders&amp;#x2019; deficit, and cash flows. In June 2014, the
 Financial Accounting Standards Board (&amp;#x201C;FASB&amp;#x201D;) issued an
 accounting standards update that eliminates the concept of a
 development stage entity from U.S. generally accepted accounting
 principles and removes the related incremental reporting
 requirements. See Note 2 below for additional information on this
 new standard. The Company elected to early adopt the new standard.
 Accordingly, in contrast to the Company&amp;#x2019;s consolidated
 financial statements and the notes thereto for the year ended
 December&amp;#xA0;31, 2013 included in Company&amp;#x2019;s Registration
 Statement on Form S-1 on file with the Securities and Exchange
 Commission (&amp;#x201C;SEC&amp;#x201D;), the consolidated financial
 statements contained in this report do not include
 inception-to-date information.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company is subject to risks common to companies in the
 biotechnology industry including, but not limited to, new
 technological innovations, protection of proprietary technology,
 dependence on key personnel, compliance with government regulations
 and the need to obtain additional financing. Product candidates
 currently under development will require significant additional
 research and development efforts, including extensive pre-clinical
 and clinical testing and regulatory approval, prior to
 commercialization. These efforts require significant amounts of
 additional capital, adequate personnel infrastructure, and
 extensive compliance-reporting capabilities.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company&amp;#x2019;s product candidates are all in the development
 stage. There can be no assurance that the Company&amp;#x2019;s research
 and development will be successfully completed, that&amp;#xA0;adequate
 protection for the Company&amp;#x2019;s intellectual property will be
 obtained, that any products developed&amp;#xA0;will obtain necessary
 government regulatory approval or that any approved products will
 be&amp;#xA0;commercially viable. Even if the Company&amp;#x2019;s product
 development efforts are successful, it is uncertain when, if ever,
 the Company will generate significant revenue from product sales.
 The Company operates in an environment of rapid change in
 technology and&amp;#xA0;substantial competition from pharmaceutical and
 biotechnology companies. In addition, the&amp;#xA0;Company is dependent
 upon the services of its employees and consultants.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The consolidated financial statements include the accounts of the
 Company and its wholly owned subsidiaries Zafgen Securities
 Corporation, Zafgen Australia Pty Limited, and Zafgen Animal
 Health, LLC. All significant intercompany balances and transactions
 have been eliminated.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The accompanying consolidated financial statements have been
 prepared in conformity with accounting principles generally
 accepted in the United States of America (&amp;#x201C;GAAP&amp;#x201D;).&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 On June&amp;#xA0;24, 2014 the Company completed an initial public
 offering (&amp;#x201C;IPO&amp;#x201D;) of its common stock, which resulted in
 the sale of 6,900,000 shares at a price of $16.00 per share. The
 Company received net proceeds from the IPO of approximately
 $102,672 based upon the price of $16.00 per share and after
 deducting underwriting discounts and commissions paid by the
 Company. The Company also incurred offering costs of $2,508 related
 to the IPO.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 18px"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt"&gt;
 &lt;b&gt;Unaudited Interim Financial Information&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The consolidated balance sheet at December&amp;#xA0;31, 2013 was
 derived from audited financial statements, but does not include all
 disclosures required by GAAP. The accompanying unaudited
 consolidated financial statements as of June&amp;#xA0;30, 2014 and for
 the three months and six months ended June&amp;#xA0;30, 2014 and 2013
 have been prepared by the Company, pursuant to the rules and
 regulations of the SEC for interim financial statements. Certain
 information and footnote disclosures normally included in financial
 statements prepared in accordance with GAAP have been condensed or
 omitted pursuant to such rules and regulations. However, the
 Company believes that the disclosures are adequate to make the
 information presented not misleading. These consolidated financial
 statements should be read in conjunction with the Company&amp;#x2019;s
 audited consolidated financial statements and the notes thereto for
 the year ended December&amp;#xA0;31, 2013 included in the
 Company&amp;#x2019;s Registration Statement on Form S-1, File Number
 333-195391 on file with the SEC. In the opinion of management, all
 adjustments, consisting only of normal recurring adjustments
 necessary for a fair statement of the Company&amp;#x2019;s consolidated
 financial position as of June&amp;#xA0;30, 2014 and consolidated
 results of operations for the three and six months ended
 June&amp;#xA0;30, 2014 and 2013 and consolidated cash flows for the six
 months ended June&amp;#xA0;30, 2014 and 2013 have been made. The
 results of operations for the three and six months ended
 June&amp;#xA0;30, 2014 are not necessarily indicative of the results of
 operations that may be expected for the year ending
 December&amp;#xA0;31, 2014.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:BusinessDescriptionAndBasisOfPresentationTextBlock>
  <us-gaap:ResearchAndDevelopmentExpensePolicy contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_8599A5C6-1A16-40CB-A45D-58AD82410C98_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Research and Development Costs&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Research and development costs are expensed as incurred. Included
 in research and development expenses are wages, stock-based
 compensation and benefits of employees, third-party license fees
 and other operational costs related to the Company&amp;#x2019;s research
 and development activities, including facility-related expenses and
 external costs of outside vendors engaged to conduct both
 pre-clinical studies and clinical trials. The Company records
 research and development expenses net of any research and
 development tax incentives the Company is entitled to receive from
 government authorities.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:ResearchAndDevelopmentExpensePolicy>
  <us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_EFC1D227-5E23-4A47-BED1-2AAE4197A43E_1_0">&lt;div&gt;
 &lt;p style="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"&gt;
 &lt;b&gt;8. Retirement Plan&lt;/b&gt;&lt;/p&gt;
 &lt;p style="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman"&gt;
 The Company has a Savings Incentive Match Plan for employees. Under
 the terms of the plan, the Company contributes 2% of an
 employee&amp;#x2019;s annual base salary, up to a maximum of the annual
 Internal Revenue Service compensation limits, for all full-time
 employees.&lt;/p&gt;
 &lt;p style="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman"&gt;
 During the three months ended June&amp;#xA0;30, 2014 and 2013, the
 Company recognized $13 and $7, respectively, of expense related to
 its contributions to this plan. During the six months ended
 June&amp;#xA0;30, 2014 and 2013, the Company recognized $26 and $14,
 respectively, of expense related to its contributions to the
 plan.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock>
  <us-gaap:ConcentrationRiskCreditRisk contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_0DD96AE3-5758-4221-A2E9-F30DDFBD47F8_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Concentration of Credit Risk and of Significant
 Suppliers&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Financial instruments that potentially expose the Company to
 concentrations of credit risk consist primarily of cash and cash
 equivalents. The Company has all cash and cash equivalents balances
 at one accredited financial institution, in amounts that exceed
 federally insured limits. The Company does not believe that it is
 subject to unusual credit risk beyond the normal credit risk
 associated with commercial banking relationships.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company is dependent on third-party manufacturers to supply
 products for research and development activities in its programs.
 In particular, the Company relies and expects to continue to rely
 on a small number of manufacturers to supply it with its
 requirements for the active pharmaceutical ingredients and
 formulated drugs related to these programs. These programs could be
 adversely affected by a significant interruption in the supply of
 active pharmaceutical ingredients and formulated drugs.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:ConcentrationRiskCreditRisk>
  <us-gaap:ResearchDevelopmentAndComputerSoftwareDisclosureTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_EB842F43-B2E4-47F0-A42B-2453EFC02594_1_0">&lt;div&gt;
 &lt;p style="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"&gt;
 &lt;b&gt;9. Australia Research and Development Tax Incentive&lt;/b&gt;&lt;/p&gt;
 &lt;p style="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman"&gt;
 The Company&amp;#x2019;s wholly owned subsidiary, Zafgen Australia Pty
 Limited, which conducts core research and development activities on
 behalf of the Company is eligible to receive a 45% refundable tax
 incentive for qualified research and development activities. For
 the three months ended June&amp;#xA0;30, 2014 and 2013, $47 and $418,
 respectively, was recorded as a reduction to research and
 development expenses in the consolidated statements of operations
 and, for the six months ended June&amp;#xA0;30, 2014 and 2013, $73 and
 $1,198, respectively, was recorded as a reduction to research and
 development expenses in the consolidated statements of operations.
 These amounts represented 45% of the Company&amp;#x2019;s qualified
 research and development spending in Australia. The refund is
 denominated in Australian dollars and, therefore, the receivable is
 re-measured into U.S. dollars as of each reporting date. For the
 three months ended June&amp;#xA0;30, 2014 and 2013, the Company
 recorded in its consolidated statements of operations unrealized
 foreign currency exchange (gains) losses of $(22) and $210,
 respectively, related to this tax incentive receivable. For the six
 months ended June&amp;#xA0;30, 2014 and 2013, the Company recorded in
 its consolidated statements of operations unrealized foreign
 currency exchange (gains) losses of $(64) and $205, respectively,
 related to this tax incentive receivable. As of June&amp;#xA0;30, 2014
 and December&amp;#xA0;31, 2013, the Company&amp;#x2019;s tax incentive
 receivable from the Australian government was $1,222 and $1,617,
 respectively.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:ResearchDevelopmentAndComputerSoftwareDisclosureTextBlock>
  <us-gaap:SegmentReportingPolicyPolicyTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_CBBC3BFB-D4C4-4FE2-9CCF-E3E2520D968E_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Segment Data&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The Company manages its operations as a single segment for the
 purposes of assessing performance and making operating decisions.
 The Company&amp;#x2019;s singular focus is on advancing novel
 therapeutics for patients suffering from severe obesity and
 obesity-related disorders. No revenue has been generated since
 inception, and all tangible assets are held in the United
 States.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:SegmentReportingPolicyPolicyTextBlock>
  <us-gaap:SignificantAccountingPoliciesTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_F30343F6-371E-4887-82FA-806454FBDC43_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;2. Summary of Significant Accounting Policies&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt"&gt;
 &lt;b&gt;Use of Estimates&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The preparation of financial statements in conformity with GAAP
 requires management to make estimates and assumptions that affect
 the reported amounts of assets and liabilities, the disclosure of
 contingent assets and liabilities at the date of the consolidated
 financial statements, and the reported amounts of expenses during
 the reporting periods. Significant estimates and assumptions
 reflected in these consolidated financial statements include, but
 are not limited to, the accrual of research and development
 expenses and the valuation of common stock prior to the IPO and
 stock-based awards. Estimates are periodically reviewed in light of
 changes in circumstances, facts and experience. Actual results
 could differ from the Company&amp;#x2019;s estimates.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Cash Equivalents&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The Company considers all short-term, highly liquid investments
 with original maturities of ninety days or less at acquisition date
 to be cash equivalents. Cash equivalents, which consist of money
 market accounts, are stated at fair value.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Concentration of Credit Risk and of Significant
 Suppliers&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Financial instruments that potentially expose the Company to
 concentrations of credit risk consist primarily of cash and cash
 equivalents. The Company has all cash and cash equivalents balances
 at one accredited financial institution, in amounts that exceed
 federally insured limits. The Company does not believe that it is
 subject to unusual credit risk beyond the normal credit risk
 associated with commercial banking relationships.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company is dependent on third-party manufacturers to supply
 products for research and development activities in its programs.
 In particular, the Company relies and expects to continue to rely
 on a small number of manufacturers to supply it with its
 requirements for the active pharmaceutical ingredients and
 formulated drugs related to these programs. These programs could be
 adversely affected by a significant interruption in the supply of
 active pharmaceutical ingredients and formulated drugs.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Fair Value Measurements&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Certain assets and liabilities are carried at fair value under
 GAAP. Fair value is defined as the exchange price that would be
 received for an asset or paid to transfer a liability (an exit
 price) in the principal or most advantageous market for the asset
 or liability in an orderly transaction between market participants
 on the measurement date. Valuation techniques used to measure fair
 value must maximize the use of observable inputs and minimize the
 use of unobservable inputs. Financial assets and liabilities
 carried at fair value are to be classified and disclosed in one of
 the following three levels of the fair value hierarchy, of which
 the first two are considered observable and the last is considered
 unobservable:&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="100%" border="0"&gt;
 &lt;tr&gt;
 &lt;td width="5%"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="top" width="2%" align="left"&gt;&amp;#x2022;&lt;/td&gt;
 &lt;td valign="top" width="1%"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="top" align="left"&gt;Level 1&amp;#x2014;Quoted prices in active
 markets for identical assets or liabilities.&lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 &lt;p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 12px"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="100%" border="0"&gt;
 &lt;tr&gt;
 &lt;td width="5%"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="top" width="2%" align="left"&gt;&amp;#x2022;&lt;/td&gt;
 &lt;td valign="top" width="1%"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="top" align="left"&gt;Level 2&amp;#x2014;Observable inputs
 (other than Level 1 quoted prices) such as quoted prices in active
 markets for similar assets or liabilities, quoted prices in markets
 that are not active for identical or similar assets or liabilities,
 or other inputs that are observable or can be corroborated by
 observable market data.&lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 6pt; MARGIN-TOP: 0pt"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="100%" border="0"&gt;
 &lt;tr&gt;
 &lt;td width="5%"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="top" width="2%" align="left"&gt;&amp;#x2022;&lt;/td&gt;
 &lt;td valign="top" width="1%"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="top" align="left"&gt;Level 3&amp;#x2014;Unobservable inputs
 that are supported by little or no market activity and that are
 significant to determining the fair value of the assets or
 liabilities, including pricing models, discounted cash flow
 methodologies and similar techniques.&lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company&amp;#x2019;s cash equivalents of $120,000 and $26,501 as of
 June&amp;#xA0;30, 2014 and December&amp;#xA0;31, 2013, respectively, were
 carried at fair value based on quoted prices in active markets, a
 Level 1 measurement. The carrying values of accounts payable and
 accrued expenses approximate their fair value due to the short-term
 nature of these liabilities. The Company&amp;#x2019;s carrying value of
 outstanding debt issued in the first quarter of 2014 approximates
 fair value based on the recent execution date of the credit
 facility agreement, and is considered a Level 2 measurement.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Deferred Offering Costs&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The Company capitalizes certain legal, accounting and other
 third-party fees that are directly associated with in-process
 equity financings as other assets until such financings are
 consummated. After consummation of the equity financing, these
 costs are recorded in stockholders&amp;#x2019; equity (deficit) as a
 reduction of additional paid-in capital generated as a result of
 the offering or as a reduction to the carrying value of preferred
 stock issued. As of December&amp;#xA0;31, 2013, the Company had
 recorded $743 of deferred offering costs, included in other assets
 in the accompanying consolidated balance sheet in contemplation of
 the Company&amp;#x2019;s IPO of its common stock which closed in June
 2014. The Company has no deferred offering costs as of
 June&amp;#xA0;30, 2014.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Property and Equipment&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Property and equipment are stated at cost less accumulated
 depreciation. Depreciation expense is recognized using the
 straight-line method over a five-year estimated useful life for
 both furniture and fixtures and office equipment. Expenditures for
 repairs and maintenance of assets are charged to expense as
 incurred. Upon retirement or sale, the cost and related accumulated
 depreciation of assets disposed of are removed from the accounts
 and any resulting gain or loss is included in loss from
 operations.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Impairment of Long-Lived Assets&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Long-lived assets consist of property and equipment. Long-lived
 assets to be held and used are tested for recoverability whenever
 events or changes in business circumstances indicate that the
 carrying amount of the assets may not be fully recoverable. Factors
 that the Company considers in deciding when to perform an
 impairment review include significant underperformance of the
 business in relation to expectations, significant negative industry
 or economic trends, and significant changes or planned changes in
 the use of the assets. If an impairment review is performed to
 evaluate a long-lived asset for recoverability, the Company
 compares forecasts of undiscounted cash flows expected to result
 from the use and eventual disposition of the long-lived asset to
 its carrying value. An impairment loss would be recognized when
 estimated undiscounted future cash flows expected to result from
 the use of an asset are less than its carrying amount. The
 impairment loss would be based on the excess of the carrying value
 of the impaired asset over its fair value, determined based on
 discounted cash flows. To date, the Company has not recorded any
 impairment losses on long-lived assets.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Research and Development Costs&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Research and development costs are expensed as incurred. Included
 in research and development expenses are wages, stock-based
 compensation and benefits of employees, third-party license fees
 and other operational costs related to the Company&amp;#x2019;s research
 and development activities, including facility-related expenses and
 external costs of outside vendors engaged to conduct both
 pre-clinical studies and clinical trials. The Company records
 research and development expenses net of any research and
 development tax incentives the Company is entitled to receive from
 government authorities.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Research Contract Costs and Accruals&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The Company has entered into various research and development
 contracts with research institutions and other companies both
 inside and outside of the United States. These agreements are
 generally cancelable, and related payments are recorded as research
 and development expenses as incurred. The Company records accruals
 for estimated ongoing research costs. When evaluating the adequacy
 of the accrued liabilities, the Company analyzes progress of the
 studies, including the phase or completion of events, invoices
 received and contracted costs. Significant judgments and estimates
 are made in determining the accrued balances at the end of any
 reporting period. Actual results could differ from the
 Company&amp;#x2019;s estimates. The Company&amp;#x2019;s historical accrual
 estimates have not been materially different from the actual
 costs.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Patent Costs&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 All patent-related costs incurred in connection with filing and
 prosecuting patent applications are recorded as general and
 administrative expenses as incurred, as recoverability of such
 expenditures is uncertain.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Accounting for Stock-Based Compensation&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The Company measures all stock options and other stock-based awards
 granted to employees and directors at the fair value on the date of
 the grant using the Black-Scholes option-pricing model. The fair
 value of the awards is recognized as expense, net of estimated
 forfeitures, over the requisite service period, which is generally
 the vesting period of the respective award. The straight-line
 method of expense recognition is applied to all awards with
 service-only conditions.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 For stock-based awards granted to consultants and nonemployees,
 compensation expense is recognized over the period during which
 services are rendered by such consultants and nonemployees until
 completed. At the end of each financial reporting period prior to
 completion of the service, the fair value of these awards is
 re-measured using the then-current fair value of the
 Company&amp;#x2019;s common stock and updated assumption inputs in the
 Black-Scholes option-pricing model.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company classifies stock-based compensation expense in its
 consolidated statement of operations and comprehensive loss in the
 same manner in which the award recipient&amp;#x2019;s payroll costs are
 classified or in which the award recipients&amp;#x2019; service payments
 are classified.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company recognizes compensation expense for only the portion of
 awards that are expected to vest. In developing a forfeiture rate
 estimate, the Company has considered its historical experience to
 estimate pre-vesting forfeitures for service-based awards. The
 impact of a forfeiture rate adjustment will be recognized in full
 in the period of adjustment, and if the actual forfeiture rate is
 materially different from the Company&amp;#x2019;s estimate, the Company
 may be required to record adjustments to stock-based compensation
 expense in future periods.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Income Taxes&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The Company accounts for income taxes using the asset and liability
 method, which requires the recognition of deferred tax assets and
 liabilities for the expected future tax consequences of events that
 have been recognized in the consolidated financial statements or in
 the Company&amp;#x2019;s tax returns. Deferred taxes are determined
 based on the difference between the financial statement and tax
 basis of assets and liabilities using enacted tax rates in effect
 in the years in which the differences are expected to reverse.
 Changes in deferred tax assets and liabilities are recorded in the
 provision for income taxes. The Company assesses the likelihood
 that its deferred tax assets will be recovered from future taxable
 income and, to the extent it believes, based upon the weight of
 available evidence, that it is more likely than not that all or a
 portion of deferred tax assets will not be realized, a valuation
 allowance is established through a charge to income tax expense.
 Potential for recovery of deferred tax assets is evaluated by
 estimating the future taxable profits expected and considering
 prudent and feasible tax planning strategies.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company accounts for uncertainty in income taxes recognized in
 the consolidated financial statements by applying a two-step
 process to determine the amount of tax benefit to be recognized.
 First, the tax position must be evaluated to determine the
 likelihood that it will be sustained upon external examination by
 the taxing authorities. If the tax position is deemed
 more-likely-than-not to be sustained, the tax position is then
 assessed to determine the amount of benefit to recognize in the
 consolidated financial statements. The amount of the benefit that
 may be recognized is the largest amount that has a greater than 50%
 likelihood of being realized upon ultimate settlement. The
 provision for income taxes includes the effects of any resulting
 tax reserves, or unrecognized tax benefits, that are considered
 appropriate as well as the related net interest and penalties.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Segment Data&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The Company manages its operations as a single segment for the
 purposes of assessing performance and making operating decisions.
 The Company&amp;#x2019;s singular focus is on advancing novel
 therapeutics for patients suffering from severe obesity and
 obesity-related disorders. No revenue has been generated since
 inception, and all tangible assets are held in the United
 States.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0px; FONT-SIZE: 1px; MARGIN-TOP: 18px"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 0pt"&gt;
 &lt;b&gt;Comprehensive Loss&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Comprehensive loss includes net loss as well as other changes in
 stockholders&amp;#x2019; equity (deficit) that result from transactions
 and economic events other than those with stockholders. For the
 three and six months ended June&amp;#xA0;30, 2014 and 2013, there was
 no difference between net loss and comprehensive loss.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Net Income (Loss) Per Share&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Upon the closing of the Company&amp;#x2019;s IPO in June 2014, all of
 the Company&amp;#x2019;s outstanding redeemable convertible preferred
 shares were converted into shares of common stock. Prior to this
 conversion, the Company followed the two-class method when
 computing net income (loss) per share as the Company had issued
 shares that meet the definition of participating securities. The
 two-class method determines net income (loss) per share for each
 class of common and participating securities according to dividends
 declared or accumulated and participation rights in undistributed
 earnings. The two-class method requires income available to common
 shareholders for the period to be allocated between common and
 participating securities based upon their respective rights to
 receive dividends as if all income for the period had been
 distributed. The Company&amp;#x2019;s redeemable convertible preferred
 shares contractually entitled the holders of such shares to
 participate in dividends, but did not contractually require the
 holders of such shares to participate in losses of the Company.
 Accordingly, the two-class method did not apply for periods in
 which the Company reported a net loss or a net loss attributable to
 common shareholders resulting from dividends or accretion related
 to its redeemable convertible preferred shares.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 Basic net income (loss) per share attributable to common
 shareholders is computed by dividing the net income (loss)
 attributable to common shareholders by the weighted average number
 of common shares outstanding for the period. Diluted net income
 (loss) per share attributable to common shareholders is computed by
 dividing the diluted net income (loss) attributable to common
 shareholders by the weighted average number of common shares,
 including potential dilutive common shares assuming the dilutive
 effect of outstanding stock options and unvested restricted common
 shares, as determined using the treasury stock method. For periods
 in which the Company has reported net losses, diluted net loss per
 common share attributable to common shareholders is the same as
 basic net loss per common share attributable to common
 shareholders, since dilutive common shares are not assumed to have
 been issued if their effect is antidilutive.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company reported a net loss attributable to common stockholders
 for the three and six months ended June&amp;#xA0;30, 2014 and 2013.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The following common stock equivalents outstanding as of
 June&amp;#xA0;30, 2014 and 2013, were excluded from the computation of
 diluted net loss per share for the three and six months ended
 June&amp;#xA0;30, 2014 and 2013, because they had an anti-dilutive
 impact:&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="76%" align="center" border="0"&gt;
 &lt;tr&gt;
 &lt;td width="75%"&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="3%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="3%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"&gt;&lt;b&gt;As of June&amp;#xA0;30,&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;2014&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;2013&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Options to purchase common stock&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;1,839,895&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;1,283,264&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Redeemable convertible preferred stock&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap" align="right"&gt;&amp;#x2014;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;78,372,931&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Total options and redeemable convertible preferred stock
 exercisable or convertible into common stock&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;1,839,895&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;79,656,195&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 3px double"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Recently Issued and Adopted Accounting Pronouncements&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 In June 2014, the FASB issued Accounting Standards Update
 No.&amp;#xA0;2014-10, Development Stage Entities (Topic 915):
 Elimination of Certain Financial Reporting Requirements, Including
 an Amendment to Variable Interest Entities Guidance in Topic 810,
 Consolidation. The amendments in this guidance remove all
 incremental financial reporting requirements for development stage
 entities.&amp;#xA0;Among other changes, this guidance will no longer
 require development stage entities to present inception-to-date
 information about income statement line items, cash flows, and
 equity transactions. This guidance is effective for public
 companies in the first annual period beginning after
 December&amp;#xA0;15, 2014.&amp;#xA0;Early application is permitted for
 interim and annual periods for which financial statements have not
 yet been issued. The Company elected to apply this disclosure
 guidance to its consolidated financial statements for the three
 months ended June&amp;#xA0;30, 2014 and as a result, no longer
 discloses inception-to-date information in its Consolidated
 Statements of Operations and Comprehensive Loss, Cash Flows and
 Stockholders&amp;#x2019; Deficit and the related notes thereto.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:SignificantAccountingPoliciesTextBlock>
  <us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" decimals="-3" id="id_5987172_BAA2EEBD-E976-4D5F-9317-22CB252204F7_1_2" unitRef="shares">1839895000</us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount>
  <us-gaap:ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_36B3B365-F12B-4C21-A0D1-4A53499F37A0_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Impairment of Long-Lived Assets&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Long-lived assets consist of property and equipment. Long-lived
 assets to be held and used are tested for recoverability whenever
 events or changes in business circumstances indicate that the
 carrying amount of the assets may not be fully recoverable. Factors
 that the Company considers in deciding when to perform an
 impairment review include significant underperformance of the
 business in relation to expectations, significant negative industry
 or economic trends, and significant changes or planned changes in
 the use of the assets. If an impairment review is performed to
 evaluate a long-lived asset for recoverability, the Company
 compares forecasts of undiscounted cash flows expected to result
 from the use and eventual disposition of the long-lived asset to
 its carrying value. An impairment loss would be recognized when
 estimated undiscounted future cash flows expected to result from
 the use of an asset are less than its carrying amount. The
 impairment loss would be based on the excess of the carrying value
 of the impaired asset over its fair value, determined based on
 discounted cash flows. To date, the Company has not recorded any
 impairment losses on long-lived assets.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock>
  <us-gaap:ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_AC2ABD46-7257-4840-812E-A99A1FD3390F_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The Company recorded stock-based compensation expense related to
 stock options and restricted common stock in the following expense
 categories of its statements of operations:&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="92%" align="center" border="0"&gt;
 &lt;tr&gt;
 &lt;td width="76%"&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="3%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="3%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="3%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="3%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"&gt;&lt;b&gt;Three&amp;#xA0;Months&amp;#xA0;Ended&lt;br /&gt;
 June&amp;#xA0;30,&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"&gt;&lt;b&gt;Six&amp;#xA0;Months&amp;#xA0;Ended&lt;br /&gt;
 June&amp;#xA0;30,&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;2014&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;2013&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;2014&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;2013&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Research and development&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;99&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;43&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;168&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;69&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 General and administrative&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;169&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;60&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;276&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;84&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;268&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;103&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;444&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;$&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;153&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 
 
 &lt;/div&gt;</us-gaap:ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock>
  <us-gaap:UseOfEstimates contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_548164F5-5E41-49B4-8CA2-5BB6A8DF6C35_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt"&gt;
 &lt;b&gt;Use of Estimates&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The preparation of financial statements in conformity with GAAP
 requires management to make estimates and assumptions that affect
 the reported amounts of assets and liabilities, the disclosure of
 contingent assets and liabilities at the date of the consolidated
 financial statements, and the reported amounts of expenses during
 the reporting periods. Significant estimates and assumptions
 reflected in these consolidated financial statements include, but
 are not limited to, the accrual of research and development
 expenses and the valuation of common stock prior to the IPO and
 stock-based awards. Estimates are periodically reviewed in light of
 changes in circumstances, facts and experience. Actual results
 could differ from the Company&amp;#x2019;s estimates.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:UseOfEstimates>
  <us-gaap:EarningsPerSharePolicyTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_1E35F6CB-3092-4670-82BD-DA94E5E50C1C_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Net Income (Loss) Per Share&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 Upon the closing of the Company&amp;#x2019;s IPO in June 2014, all of
 the Company&amp;#x2019;s outstanding redeemable convertible preferred
 shares were converted into shares of common stock. Prior to this
 conversion, the Company followed the two-class method when
 computing net income (loss) per share as the Company had issued
 shares that meet the definition of participating securities. The
 two-class method determines net income (loss) per share for each
 class of common and participating securities according to dividends
 declared or accumulated and participation rights in undistributed
 earnings. The two-class method requires income available to common
 shareholders for the period to be allocated between common and
 participating securities based upon their respective rights to
 receive dividends as if all income for the period had been
 distributed. The Company&amp;#x2019;s redeemable convertible preferred
 shares contractually entitled the holders of such shares to
 participate in dividends, but did not contractually require the
 holders of such shares to participate in losses of the Company.
 Accordingly, the two-class method did not apply for periods in
 which the Company reported a net loss or a net loss attributable to
 common shareholders resulting from dividends or accretion related
 to its redeemable convertible preferred shares.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 Basic net income (loss) per share attributable to common
 shareholders is computed by dividing the net income (loss)
 attributable to common shareholders by the weighted average number
 of common shares outstanding for the period. Diluted net income
 (loss) per share attributable to common shareholders is computed by
 dividing the diluted net income (loss) attributable to common
 shareholders by the weighted average number of common shares,
 including potential dilutive common shares assuming the dilutive
 effect of outstanding stock options and unvested restricted common
 shares, as determined using the treasury stock method. For periods
 in which the Company has reported net losses, diluted net loss per
 common share attributable to common shareholders is the same as
 basic net loss per common share attributable to common
 shareholders, since dilutive common shares are not assumed to have
 been issued if their effect is antidilutive.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company reported a net loss attributable to common stockholders
 for the three and six months ended June&amp;#xA0;30, 2014 and 2013.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The following common stock equivalents outstanding as of
 June&amp;#xA0;30, 2014 and 2013, were excluded from the computation of
 diluted net loss per share for the three and six months ended
 June&amp;#xA0;30, 2014 and 2013, because they had an anti-dilutive
 impact:&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 12pt; MARGIN-TOP: 0pt"&gt;
 &amp;#xA0;&lt;/p&gt;
 &lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; BORDER-COLLAPSE: collapse" cellspacing="0" cellpadding="0" width="76%" align="center" border="0"&gt;
 &lt;tr&gt;
 &lt;td width="75%"&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="3%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td valign="bottom" width="3%"&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;td&gt;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="6" align="center"&gt;&lt;b&gt;As of June&amp;#xA0;30,&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;2014&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td style="BORDER-BOTTOM: #000000 1pt solid" valign="bottom" colspan="2" align="center"&gt;&lt;b&gt;2013&lt;/b&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Options to purchase common stock&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;1,839,895&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;1,283,264&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Redeemable convertible preferred stock&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap" align="right"&gt;&amp;#x2014;&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;78,372,931&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 1px"&gt;
 &lt;td valign="bottom"&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;
 &lt;p style="BORDER-TOP: #000000 1px solid"&gt;&amp;#xA0;&lt;/p&gt;
 &lt;/td&gt;
 &lt;td&gt;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;tr style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman" bgcolor="#CCEEFF"&gt;
 &lt;td valign="top"&gt;
 &lt;p style="FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-LEFT: 1em; TEXT-INDENT: -1em"&gt;
 Total options and redeemable convertible preferred stock
 exercisable or convertible into common stock&lt;/p&gt;
 &lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;1,839,895&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&lt;font style="FONT-SIZE: 8pt"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
 &lt;td valign="bottom"&gt;&amp;#xA0;&lt;/td&gt;
 &lt;td valign="bottom" align="right"&gt;79,656,195&lt;/td&gt;
 &lt;td valign="bottom" nowrap="nowrap"&gt;&amp;#xA0;&amp;#xA0;&lt;/td&gt;
 &lt;/tr&gt;
 &lt;/table&gt;
 &lt;/div&gt;</us-gaap:EarningsPerSharePolicyTextBlock>
  <us-gaap:IncomeTaxPolicyTextBlock contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" id="id_5987172_EED7C005-FD89-467F-8336-6BC5CD186F2E_1_0">&lt;div&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 18pt"&gt;
 &lt;b&gt;Income Taxes&lt;/b&gt;&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 6pt; TEXT-INDENT: 4%"&gt;
 The Company accounts for income taxes using the asset and liability
 method, which requires the recognition of deferred tax assets and
 liabilities for the expected future tax consequences of events that
 have been recognized in the consolidated financial statements or in
 the Company&amp;#x2019;s tax returns. Deferred taxes are determined
 based on the difference between the financial statement and tax
 basis of assets and liabilities using enacted tax rates in effect
 in the years in which the differences are expected to reverse.
 Changes in deferred tax assets and liabilities are recorded in the
 provision for income taxes. The Company assesses the likelihood
 that its deferred tax assets will be recovered from future taxable
 income and, to the extent it believes, based upon the weight of
 available evidence, that it is more likely than not that all or a
 portion of deferred tax assets will not be realized, a valuation
 allowance is established through a charge to income tax expense.
 Potential for recovery of deferred tax assets is evaluated by
 estimating the future taxable profits expected and considering
 prudent and feasible tax planning strategies.&lt;/p&gt;
 &lt;p style="MARGIN-BOTTOM: 0pt; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman; MARGIN-TOP: 12pt; TEXT-INDENT: 4%"&gt;
 The Company accounts for uncertainty in income taxes recognized in
 the consolidated financial statements by applying a two-step
 process to determine the amount of tax benefit to be recognized.
 First, the tax position must be evaluated to determine the
 likelihood that it will be sustained upon external examination by
 the taxing authorities. If the tax position is deemed
 more-likely-than-not to be sustained, the tax position is then
 assessed to determine the amount of benefit to recognize in the
 consolidated financial statements. The amount of the benefit that
 may be recognized is the largest amount that has a greater than 50%
 likelihood of being realized upon ultimate settlement. The
 provision for income taxes includes the effects of any resulting
 tax reserves, or unrecognized tax benefits, that are considered
 appropriate as well as the related net interest and penalties.&lt;/p&gt;
 &lt;/div&gt;</us-gaap:IncomeTaxPolicyTextBlock>
  <us-gaap:ForeignCurrencyTransactionGainLossBeforeTax contextRef="eol_PE720058--1410-Q0002_STD_181_20140630_0" decimals="-3" id="id_5987172_22944915-D338-4DEA-8A11-3FD0FE0F87E4_3_9" unitRef="iso4217_USD">93000</us-gaap:ForeignCurrencyTransactionGainLossBeforeTax>
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 &lt;b&gt;Unaudited Interim Financial Information&lt;/b&gt;&lt;/p&gt;
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 The consolidated balance sheet at December&amp;#xA0;31, 2013 was
 derived from audited financial statements, but does not include all
 disclosures required by GAAP. The accompanying unaudited
 consolidated financial statements as of June&amp;#xA0;30, 2014 and for
 the three months and six months ended June&amp;#xA0;30, 2014 and 2013
 have been prepared by the Company, pursuant to the rules and
 regulations of the SEC for interim financial statements. Certain
 information and footnote disclosures normally included in financial
 statements prepared in accordance with GAAP have been condensed or
 omitted pursuant to such rules and regulations. However, the
 Company believes that the disclosures are adequate to make the
 information presented not misleading. These consolidated financial
 statements should be read in conjunction with the Company&amp;#x2019;s
 audited consolidated financial statements and the notes thereto for
 the year ended December&amp;#xA0;31, 2013 included in the
 Company&amp;#x2019;s Registration Statement on Form S-1, File Number
 333-195391 on file with the SEC. In the opinion of management, all
 adjustments, consisting only of normal recurring adjustments
 necessary for a fair statement of the Company&amp;#x2019;s consolidated
 financial position as of June&amp;#xA0;30, 2014 and consolidated
 results of operations for the three and six months ended
 June&amp;#xA0;30, 2014 and 2013 and consolidated cash flows for the six
 months ended June&amp;#xA0;30, 2014 and 2013 have been made. The
 results of operations for the three and six months ended
 June&amp;#xA0;30, 2014 are not necessarily indicative of the results of
 operations that may be expected for the year ending
 December&amp;#xA0;31, 2014.&lt;/p&gt;
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 The Company has entered into various research and development
 contracts with research institutions and other companies both
 inside and outside of the United States. These agreements are
 generally cancelable, and related payments are recorded as research
 and development expenses as incurred. The Company records accruals
 for estimated ongoing research costs. When evaluating the adequacy
 of the accrued liabilities, the Company analyzes progress of the
 studies, including the phase or completion of events, invoices
 received and contracted costs. Significant judgments and estimates
 are made in determining the accrued balances at the end of any
 reporting period. Actual results could differ from the
 Company&amp;#x2019;s estimates. The Company&amp;#x2019;s historical accrual
 estimates have not been materially different from the actual
 costs.&lt;/p&gt;
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