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</LabelSeparator><CurrencyCode /><FootnoteIndexer /><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios><MCU><KeyName /><CurrencySymbol /><contextRef><ContextID>eol_PE10315---1310-Q0011_STD_181_20130630_0</ContextID><EntitySchema>http://www.sec.gov/CIK</EntitySchema><EntityValue>0001069308</EntityValue><PeriodDisplayName /><PeriodType>duration</PeriodType><PeriodStartDate>2013-01-01T00:00:00</PeriodStartDate><PeriodEndDate>2013-06-30T00:00:00</PeriodEndDate><Segments /><Scenarios /></contextRef><UPS /><CurrencyCode /><OriginalCurrencyCode /></MCU><CurrencySymbol /><Labels><Label Key="CalendarSupplement" Id="0" Label="6 Months Ended" /><Label Key="Calendar" Id="1" Label="Jun. 30, 2013" /></Labels></Column></Columns><Rows><Row FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

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&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"&gt;
Note 4.&amp;#xA0;&amp;#xA0;Restricted Cash&lt;/font&gt;&lt;/div&gt;
&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block"&gt;&lt;br /&gt;&lt;/div&gt;
&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;Pursuant
to the July 2012 Note financing, $1.0 million of the gross proceeds
were initially required to be maintained in a segregated account
and subject to a deposit control agreement while the July 2012
Notes are outstanding.&amp;#xA0;&amp;#xA0;Pursuant to a waiver executed by
the holders of in excess of two-thirds (66-2/3%) of the principal
amount of the outstanding July 2012 Notes and accepted by Opexa,
the amount of the cash subject to the deposit control agreement was
reduced to $500,000 on January 29, 2013.&amp;#xA0;&amp;#xA0;In exchange for
such waiver, the Company issued warrants to the holders of the July
2012 Notes to purchase an aggregate of 187,500 shares of the
Company&amp;#x2019;s common stock (see Note 10).&amp;#xA0;&amp;#xA0;As of June
30, 2013, the $500,000 balance in the controlled account is
reported as restricted cash in the consolidated balance
sheets.&lt;/font&gt;&lt;/div&gt;
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