Stockholders' Equity

6 Months Ended

Jun. 30, 2015

Equity [Abstract]

Stockholders' Equity

2. Stockholders’ Equity

March 2015 Financing

On March 25, 2015, the Company completed a financing with institutional investors in which it raised $10.0 million, or approximately $9.2 million after deducting placement agents’ fees and other offering expenses. Investors purchased shares of the Company’s common stock at a price of $1.7125 per share and received one warrant to purchase one half of a share of the Company’s common stock at the same exercise price per share as each share of common stock purchased. A total of 5,839,420 shares of common stock and warrants for the purchase of 2,919,710 shares of common stock were issued. The warrants were exercisable immediately after issuance and expire 5 years from the date of issuance. Also, in connection with the financing, the Company issued to its placement agent and related persons warrants to purchase 233,577 shares of the Company’s common stock, which were exercisable immediately after issuance, have an exercise price of $2.13 per share and expire on March 20, 2020.

Warrants

The following is a summary of the Company’s outstanding common stock warrants as of June 30, 2015 and December 31, 2014:

				Number of warrants (In thousands)
Warrants Issued in Connection with:	Expiration Date	Exercise Price		June 30, 2015		December 31, 2014
Private Placement Series A	04/16/18	$	3.40		1,460		1,460
Private Placement Series B	04/16/15	$	3.40		—		757
2013 Private Placement	09/23/18	$	2.80		147		147
2014 Public Offering	02/18/19	$	2.75		1,872		1,872
2014 Public Offering	02/18/19	$	2.56		293		293
2014 Private Placement	08/28/19	$	2.90		2,700		2,700
2014 Private Placement	08/28/19	$	3.70		216		216
2015 Private Placement	03/25/20	$	1.71		2,920		—
2015 Private Placement	03/20/20	$	2.13		234		—
Total Warrants Outstanding					9,842		7,445

The Private Placement Series B warrants expired unexercised on April 16, 2015.

Options and restricted stock

At the Company’s 2015 annual meeting, stockholders approved the Company’s 2015 Equity Incentive Plan (the “2015 Plan”). Under the 2015 Plan, up to 4,000,000 shares of the Company’s common stock may be issued pursuant to awards granted in the form of incentive stock options, nonqualified stock options, restricted and unrestricted stock awards, and other stock-based awards to employees, consultants, and directors. The 2015 Plan also allows additional shares of the Company’s common stock to be issued if awards outstanding under the Company’s 2005 Stock Plan (the “2005 Plan”) are cancelled, forfeited, surrendered, or terminated after the expiration of the 2005 Plan, provided that no more than 725,781 shares of the Company’s common stock shall be added to the 2015 Plan from the 2005 Plan.

The following is a summary of the Company’s stock option activity under its 2005 and 2015 Plans for the six months ended June 30, 2015:

	Options Available for Grant			Options Outstanding			Weighted Average Exercise Price		Weighted Average Remaining Contractual Life		Aggregate Intrinsic Value
	(In thousands)								(Years)		(In thousands)
Balance at December 31, 2014		54			672		$	3.63		8.49
Options granted		(1,423	)		1,423		$	1.44
Options forfeited		190			(190	)	$	1.93
Options expired		(60	)		—		$	2.67
Options authorized		4,000			—		$	—
Balance at June 30, 2015		2,761			1,905		$	2.16		8.78	$	—
Exercisable at June 30, 2015					493		$	3.28		8.10	$	—
Vested and expected to vest at June 30, 2015					1,322		$	2.39		8.51	$	—

As of June 30, 2015, there was approximately $1.07 million of unrecognized compensation cost related to stock option awards that is expected to be recognized as expense over a weighted average period of approximately 2.8 years.

The fair values for the stock options granted in the six-month period ended June 30, 2015 were estimated at the date of grant using the Black-Scholes option pricing model with the following weighted-average assumptions:

Weighted Average Assumptions
	Six months ended June 30,
	2015			2014
Risk-free interest rate		1.69	%		1.56	%
Expected life (years)		6			4
Expected volatility		92	%		101	%
Dividend yield		0.00	%		0.00	%

Options issued during the six month period ended June 30, 2015 generally vest over a three or four year period from the date of grant, except for options to purchase 75,000 shares of common stock which will only vest upon a change of control of the Company if certain other conditions are also met.