Equity (Tables)

3 Months Ended

Mar. 31, 2017

Equity [Abstract]

Summary of Stock Option Activity

The following table summarizes stock option activity under the 2014 Plan:

	Number of Shares			Weighted Average Exercise Price Per Share		Aggregate Intrinsic Value
Outstanding at December 31, 2016		2,664,832		$	6.16
Granted		—
Exercised		—
Cancelled		(103,542	)	$	7.49
Outstanding at March 31, 2017		2,561,290		$	6.11	$	—
Exercisable at March 31, 2017		1,146,966		$	5.51	$	—
Weighted-average years remaining on contractual life		8.24
Unrecognized compensation cost related to non-vested    stock options	$	7,170

The following table summarizes stock option activity under the 2004 Plan:

	Number of Shares			Weighted Average Exercise Price Per Share		Aggregate Intrinsic Value
Outstanding at December 31, 2016		10,626		$	40.58
Exercised		—
Expired		(97	)	$	40.58
Cancelled		—
Outstanding at March 31, 2017		10,529		$	40.58	$	—
Exercisable at March 31, 2017		10,529		$	40.58	$	—
Weighted-average years remaining on contractual life		1.01
Unrecognized compensation cost related to non-vested    stock options	$	—

Summary of RSU Activity

The following table summarizes RSU activity under the 2014 Plan:

	Number of Shares			Weighted Average Grant Date Fair Value Per Share
Outstanding at December 31, 2016		470,000		$	6.50
Granted		931,000		$	1.60
Vested		—
Cancelled		(60,000	)	$	1.70
Outstanding at March 31, 2017		1,341,000		$	1.57

Schedule of Stock-Based Compensation Expense

Stock-based compensation expense for options, restricted stock units (“RSU’s”) and the ESPP is reflected in the consolidated statements of operations as follows:

	Three Months Ended March 31,
	2017		2016
Research and development	$	303	$	209
General and administrative		481		277
Total	$	784	$	486