The Company has authorized 150,000,000 shares of common stock, $0.0001 par value per share, of which 82,207,405 shares, and 64,672,893 shares were issued and outstanding as of September 30, 2020, and December 31, 2019, respectively.

On January 30, 2019, the Company consummated an underwritten public offering of shares of its common stock pursuant to which the Company sold an aggregate of 6,198,500 shares of its common stock, including 808,500 shares sold pursuant to the full exercise of the underwriters’ option to purchase additional shares, at a purchase price of $6.50 per share with gross proceeds to the Company totaling $40,290,250, less issuance costs incurred of approximately $2,572,000.

On February 11, 2020, the Company consummated an underwritten public offering of shares of its common stock pursuant to which the Company sold an aggregate of 7,666,667 shares of its common stock, including 1,000,000 shares sold pursuant to the full exercise of the underwriters’ option to purchase additional shares, at a purchase price of $6.00 per share with gross proceeds to the Company totaling $46,000,000, less estimated issuance costs incurred of approximately $3,147,000.

On April 7, 2020, the Company entered into the April 2020 Sale Agreement with Jefferies pursuant to which Jefferies served as the Company’s sales agent to sell up to $75,000,000 of shares of the Company’s common stock through an “at the market offering.” Sales of common stock under the April 2020 Sale Agreement were made pursuant to an effective registration statement for an aggregate offering of up to $75,000,000. During the three and nine months ended September 30, 2020, the Company sold 1,504,473 and 9,618,267, respectively, shares of its common stock under the April 2020 Sale Agreement for which the Company received net proceeds of approximately $11,331,889 and $71,709,534, respectively through September 30, 2020. In October 2020, the Company sold an additional 921,107 shares of its common stock under the April 2020 Sale Agreement for net proceeds of approximately $1,032,744.

On August 7, 2020, the Company entered into the August 2020 Sale Agreement with Jefferies pursuant to which Jefferies is serving as the Company’s sales agent to sell shares of the Company’s common stock through an “at the market offering.” As of August 7, 2020, the company was authorized to sell up to $150,000,000 of shares of the Company’s common stock pursuant to the August 2020 Sale Agreement. During the three and nine months ended September 30, 2020, the Company did not sell any shares from the August 2020 Sale Agreement. In October 2020, the Company sold 908,727 shares of its common stock under the August 2020 Sale Agreement for net proceeds of approximately $953,590 pursuant to an effective registration statement.

During the three and nine months ended September 30, 2020, the Company issued 47,084 and 249,578 shares of common stock upon the exercise of stock options to purchase common stock and the Company received proceeds of $271,928 and $574,233 from these exercises, respectively. During the three and nine months ended September 30, 2019, the Company issued 28,800 and 107,029 shares of common stock upon the exercise of stock options to purchase common stock and the Company received proceeds of $80,100 and $386,811 from these exercises, respectively.

No warrants were exercised during the three and nine months ended September 30, 2020. During the nine months ended September 30, 2019, warrants to purchase 1,283,500 shares of common stock were exercised on a cashless basis resulting in the issuance of 1,119,868 shares of common stock. No warrants were exercised during the three months ended September 30, 2019.