5. Common Stock

As of December 31, 2017, the Company had 800,000,000 shares of authorized common stock, $0.001 par value per share, and had 24,274,494 shares issued and outstanding.

The holders of common stock are entitled to one vote for each share of common stock held.

On March 15, 2016, the Company accepted subscription agreements representing investor commitments totaling $5,004,370 in a private placement offering to investors who participated in the March 2015 private placement on a pro-rata basis to their participation in the March 2015 private placement of 327,083 shares of the Company’s common stock at a purchase price of $15.30 per share. The purchasers included 7 members of the Company’s board of directors including Dr. Raymond F. Schinazi and Dr. Phil Frost.

On September 1, 2016, the Company closed on proceeds of $4,008,201 in a private placement offering of 325,870 shares of the Company’s common stock at a purchase price of $12.30 per share. The purchasers included three members of the Company’s board of directors, including Chairman Dr. Raymond F. Schinazi, Interim Chief Executive Officer Dr. Gary Wilcox, and Dr. David Block. In addition, OPKO Health, Inc., of which the Company’s director Dr. Phillip Frost is Chairman and Chief Executive Officer, invested in the Offering.

On April 20, 2017, the Company closed on proceeds of $3,000,000 in a private placement offering of 416,667 shares of the Company’s common stock at a purchase price of $7.20 per share to three accredited investors, which included Chairman Dr. Raymond F. Schinazi and OPKO Health, Inc., of which the Company’s director Dr. Phillip Frost is Chairman and Chief Executive Officer.