5. Warrants

On July 17, 2018, the Company announced the closing of an underwritten public offering (the “Public Offering”) of Class A Units, priced at a public offering price of $1.00 per unit, with each unit consisting of one share of common stock and a seven-year warrant to purchase one share of common stock with an exercise price of $1.00 per share, and Class B Units, priced at a public offering price of $1.00 per unit, with each unit comprised of one share of series D preferred stock (the “Series D Preferred Stock”), which is convertible into one share of common stock, and a seven-year warrant to purchase one share of common stock with an exercise price of $1.00 per share. The exercise price of the warrants are fixed and do not contain any variable pricing features or any price based anti-dilutive features.

The exercise price of the warrants is subject to appropriate adjustment in the event of recapitalization events, stock dividends, dilutive issuances, stock splits, stock combinations, reclassifications, reorganizations or similar events affecting the Company’s common stock.

A total of 13,800,000 warrants to purchase 13,800,000 shares of common stock were issued in the Public Offering.

On April 6, 2018 (the “Closing Date”), the Company entered into a securities purchase agreement with certain institutional investors for the purchase and sale of 900,000 shares of the Company’s common stock in a registered direct offering at a purchase price of $2.00 per share. The Company also issued unregistered warrants to the investors in a concurrent private placement to purchase up to an equivalent number of shares of the Company’s common stock with an exercise price of $2.00 per share. The warrants are exercisable six months following the Closing Date and will expire five years from the date of issuance. A summary of warrant activity for the year ended December 31, 2017 and the nine months ended September 30, 2018 is as follows:

The warrants outstanding as of September 30, 2018 are as follows: