The Company has authorized 150,000,000 shares of common stock, $0.0001 par value per share, of which 50,223,010 shares and 44,681,745 shares were issued and outstanding as of September 30, 2017 and December 31, 2016, respectively.

On February 28, 2017, the Company entered into a securities purchase agreement providing for the issuance and sale by the Company of 3,887,815 shares of its common stock in a registered direct offering to institutional and accredited investors at a purchase price of $7.00 per share with gross proceeds to the Company totaling $27,214,705 less issuance costs of approximately $36,291.

In November 2016, the Company entered into a sales agreement with Cantor Fitzgerald (“Cantor”) under which the Company directed Cantor as its placement agent to sell common stock under an “At the Market Offering” (“Sales Agreement”). Sales of common stock under the Sales Agreement were made pursuant to an effective registration statement for an aggregate offering of up to $35 million, under which the Company sold an aggregate of approximately $15.4 million of common stock through September 30, 2017. Under the Sales Agreement, the Company was obligated to pay Cantor a 3% commission on gross proceeds. During the three months ended March 31, 2017, the Company sold 1,413,633 shares of its common stock under the Sales Agreement at an average selling price of approximately $9.71 per share for gross proceeds of $13,724,591 and net proceeds of $13,268,208. The Company did not sell any shares of its common stock under the Sales Agreement in the second or third quarter of 2017 and terminated the Sales Agreement in connection with the October 2017 Offering.

During the three months ended September 30, 2017, the Company issued 2,500 shares of common stock upon the exercise of stock options to purchase common stock and the Company received proceeds of $8,250 from these exercises. During the nine months ended September 30, 2017, the Company issued 239,817 shares of common stock upon the exercise of stock options to purchase common stock and the Company received proceeds of $109,053 from these exercises.

On October 26, 2017, the Company consummated an underwritten public offering of shares of its common stock pursuant to which the Company sold an aggregate of 4,650,000 shares of its common stock to institutional investors at a purchase price of $7.00 per share with gross proceeds to the Company totaling $32,550,000, less estimated issuance costs of approximately $2,153,000. The Company also granted the underwriters a 30-day option to purchase up to an additional 697,500 shares of common stock on the same terms as the underwriters are purchasing the base number of shares.