Stockholders' Equity

3 Months Ended

Mar. 31, 2016

Equity [Abstract]

Stockholders' Equity

13. Stockholders’ Equity

Underwritten Public Offering of Common Stock and Warrants

In February 2016, we completed an underwritten public offering with gross proceeds of $8.0 million from the sale and issuance of 29,090,910 units, each consisting of one share of our common stock and one warrant to purchase one share of our common stock.  Net proceeds, after deducting underwriting discounts and commissions and other estimated offering expenses, were approximately $7.3 million. The warrants have an exercise price of $0.42 per share, are exercisable any time on or after August 17, 2016 and will expire on February 16, 2021.

“At the Market” Equity Offering Program

In February 2014, we entered into a sales agreement with Cowen and Company, LLC (“Cowen”), to sell shares of our common stock, with aggregate gross sales proceeds of up to $30.0 million, from time to time, through an “at the market,” or ATM, equity offering program (the “2014 Sales Agreement”), under which Cowen acted as sales agent. In August 2015, we terminated the 2014 Sales Agreement upon entry into a new sales agreement with Cowen to sell shares of our common stock, with aggregate gross sales proceeds of up to $30.0 million, from time to time, through an ATM program.  As of March 31, 2016, we had sold and issued an aggregate of 24,990,267 shares at a weighted-average sales price of $0.70 per share under the ATM programs for aggregate gross proceeds of $17.5 million and $16.6 million in net proceeds, after deducting sales agent commission and discounts and our other offering costs.

Shares Issuable to Former SynthRx Stockholders Upon Achievement of Milestones

In April 2011, we acquired SynthRx as a wholly-owned subsidiary through a merger transaction in exchange for shares of our common stock and rights to additional shares of our common stock upon achievement of specified milestones related to the development of MST-188 in sickle cell disease. We have issued an aggregate of 3,050,851 shares of our common stock to the former SynthRx stockholders, 1,454,079 of which we repurchased in December 2012 for $0.001 per share pursuant to our exercise of a repurchase right under the merger agreement. We could issue up to an aggregate of 12,478,050 additional shares of our common stock to the former SynthRx stockholders if and when the development of MST-188 achieves the following milestones: (a) 3,839,400 shares upon acceptance for review by the U.S. Food and Drug Administration (“FDA”) of a new drug application (“NDA”) covering the use of purified poloxamer 188 for the treatment of sickle cell crisis in children and (b) 8,638,650 shares upon approval of such NDA by the FDA.

Warrants Issued to Hercules

In connection with the Loan Agreement, we entered into a Warrant Agreement with Hercules Technology III, L.P., dated August 11, 2015, as amended by the First Amendment thereto dated September 28, 2015 and the Second Amendment thereto dated February 25, 2016, pursuant to which Hercules has a right to purchase up to an aggregate of 2,272,727 shares of our common stock at an exercise price of $0.275 per share, at any time, or from time to time, through August 11, 2020.  The Warrant Agreement, as amended, provides for adjustment to the exercise price and number of shares subject to Hercules’ warrants in the event of a merger event, reclassification of our common stock, subdivision or combination of our common stock, or certain dividend payments. Upon exercise, the aggregate exercise price may be paid, at Hercules’ election, in cash or on a net issuance basis, based upon the fair market value of our common stock at the time of exercise.  If the fair market value of our common stock is greater than the exercise price of the warrants as of immediately before their expiration, to the extent the warrants are not previously exercised in full, the warrants shall be deemed automatically exercised on a net issuance basis as of immediately before their expiration.

Outstanding Warrants

At March 31, 2016, outstanding warrants to purchase shares of common stock are as follows:

Shares Underlying Outstanding Warrants		Exercise Price		Expiration Date
	10,625,000	$	1.100	November 2016
	28,097,400	$	0.650	June 2018
	13,081,428	$	0.010	November 2019
	22,011,265	$	0.750	November 2019
	2,272,727	$	0.275	August 2020
	29,090,910	$	0.420	February 2021
	105,178,730