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&lt;p style="MARGIN: 0in 0in 0pt;"&gt;&lt;b&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold;" size="2"&gt;6. Convertible Notes&lt;/font&gt;&lt;/b&gt;&lt;/p&gt;
&lt;p style="MARGIN: 0in 0in 0pt;"&gt;&amp;#160;&lt;/p&gt;
&lt;p style="MARGIN: 0in 0in 0pt;"&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt;" size="2"&gt;On March 16, 2010, in connection with the redemption of the Series A preferred stock, the Company issued a Senior Convertible Note (&amp;#8220;the 2.45% Convertible Note&amp;#8221;) in the amount of $1.25 million.&amp;#160; The 2.45% Convertible Note was initially recorded at fair value of $0.90 million. The 2.45% Convertible Note and the related interest expense are due on March 16, 2015. Interest is being charged at a rate of 2.45% per annum.&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN: 0in 0in 0pt;"&gt;&amp;#160;&lt;/p&gt;
&lt;p style="MARGIN: 0in 0in 0pt;"&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt;" size="2"&gt;Upon the occurrence of a qualified financing event as defined in the agreement, the 2.45% Convertible Note and any accrued interest are mandatorily convertible into shares of the same securities issued in the qualified financing at the same price per share used in the qualified financing.&amp;#160; In addition, upon the occurrence of a non-qualified financing event, as defined in the agreement, the 2.45% Convertible Note and any accrued interest are convertible at the option of the holder into cash or shares (the &amp;#8220;Put Option&amp;#8221;) of the same securities issued in the non-qualified financing event at the same price per share used in the non-qualified financing event, or the holder may elect to continue to retain the note.&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN: 0in 0in 0pt;"&gt;&amp;#160;&lt;/p&gt;
&lt;p style="MARGIN: 0in 0in 0pt;"&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt;" size="2"&gt;The Put Option was recorded at approximately $111,000, its fair value on the date of issuance and is marked to fair value at each reporting period.&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN: 0in 0in 0pt;"&gt;&amp;#160;&lt;/p&gt;
&lt;p style="MARGIN: 0in 0in 0pt;"&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt;" size="2"&gt;On July 26, 2012, the Company and NB Athyrium LLC, the holder of the 2.45% Convertible Notes, entered into an amendment to the 2.45% Convertible Notes pursuant to which NB Athyrium agreed to accelerate repayment of $625,000 in principal amount, plus accrued interest thereon, of such note in cash, at the time of the initial public offering, and convert the remaining $625,000 in principal amount, plus accrued interest thereon, into shares of our common stock at the initial public offering price.&amp;#160; On November 14, 2012, the Company and NB Athyrium LLC, entered into an additional amendment to the 2.45% Convertible Notes pursuant to which NB Athyrium agreed to cancel the acceleration and defer the repayment of $625,000 in principal amount, plus accrued interest thereon, of such note in cash until February 28, 2014&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN: 0in 0in 0pt;"&gt;&amp;#160;&lt;/p&gt;
&lt;p style="MARGIN: 0in 0in 0pt;"&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt;" size="2"&gt;As a result of the successful completion of the IPO in January 2013,&lt;/font&gt; &lt;font style="FONT-SIZE: 10pt;" size="2"&gt;$625,000 in principal amount, plus accrued interest thereon, of the 2.45% Convertible Note converted into 66,913 shares of our common stock at the initial public offering price of $10.00 per share.&amp;#160;&lt;/font&gt; &lt;font style="FONT-SIZE: 10pt;" size="2"&gt;In April 2013,&lt;/font&gt; &lt;font style="FONT-SIZE: 10pt;" size="2"&gt;the Company and NB Athyrium LLC, the holder of the 2.45% Convertible Notes, entered into an amendment to the 2.45% Convertible Notes pursuant to which NB Athyrium agreed to convert the remaining $625,000 in principal amount, plus accrued interest thereon, into 67,198&amp;#160; shares of our common stock at the initial public offering price of $10.00 per share.&amp;#160; As of June 30, 2013, all of the convertible notes obligations had been satisfied.&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN: 0in 0in 0pt;"&gt;&amp;#160;&lt;/p&gt;
&lt;p style="MARGIN: 0in 0in 0pt;"&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt;" size="2"&gt;In January 2012, the Company issued $0.9 million of convertible notes (the &amp;#8220;1.27% Convertible Notes&amp;#8221;) at face value for cash. As a result of the successful completion of the IPO in January 2013, the 1.27% Convertible Notes and related accrued interest were converted into 99,856 shares of our common stock at a conversion price equal to 87.5% of the&lt;/font&gt; &lt;font style="FONT-SIZE: 10pt;" size="2"&gt;initial public offering&lt;/font&gt; &lt;font style="FONT-SIZE: 10pt;" size="2"&gt;of $10.00 per share. A beneficial conversion charge of $125,000, the difference between the conversion price and the fair value of the new shares multiplied by the number of shares, was recorded to earnings with a corresponding credit to additional paid-in capital.&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN: 0in 0in 0pt;"&gt;&amp;#160;&lt;/p&gt;
&lt;p style="MARGIN: 0in 0in 0pt;"&gt;&lt;font style="FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt;" size="2"&gt;During the three months ended June 30, 2013 and 2012, the Company recorded interest expense of approximately $0, and $17,720, respectively, related to the amortization of the debt discount.&amp;#160; During the six months ended June 30, 2013 and 2012, the Company recorded interest expense of approximately$76,355 and $36,071, respectively, related to the amortization of the debt discount.&lt;/font&gt;&lt;/p&gt;
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