As of June 30, 2018, the Company was authorized to issue 100 million shares of common stock, par value $0.001 per share, of which 30,031,225 and 26,519,394 shares were issued and outstanding as of June 30, 2018 and December 31, 2017, respectively.

On March 13, 2018, the Company issued 3.5 million shares of common stock in a registered public offering at a price of $2.40 per share, for aggregate gross proceeds of $8.4 million. In connection with the transaction, $0.6 million was incurred for legal and underwriting fees resulting in net proceeds of $7.8 million. Pursuant to this offering, the underwriters had the option to purchase up to an additional 525,000 shares of common stock for 30 days following the pricing of the initial closing, which option was not exercised.

During the six-month period ended June 30, 2018, 29,375 warrants were exercised to purchase shares of common stock at a price of $2.00 per share in cashless exercises that resulted in the issuance of 11,831 shares of common stock.