Share-based Compensation (Tables)

6 Months Ended

Jun. 30, 2017

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Non-cash, Share-based Compensation Expense

For the three and six month periods ended June 30, 2017 and 2016, the Company recognized the following non-cash, share-based compensation expense in the statements of operations (in thousands):

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Research and development	$	44	$	53	$	80	$	95
General and administrative		75		130		140		243
Total	$	119	$	183	$	220	$	338

Summary of Stock Option Activities

Stock option transactions for the six month period ended June 30, 2017 under the Company’s stock incentive plans were as follows:

	Number of Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (in years)
Options outstanding at December 31, 2016		629,629		$	6.30		8.86
Granted		469,600			2.54
Exercised	—			—
Forfeited and cancelled		(277,604	)		3.38
Options outstanding at June 30, 2017		821,625		$	5.14		8.90
Options exercisable at June 30, 2017		251,748		$	10.32		7.62
Options vested and expected to vest		820,235		$	5.14		8.90

Summary of RSU Activity

Stock award transactions related to restricted stock units for the six month period ended June 30, 2017 under the Company’s stock incentive plans were as follows:

	Number of Shares			Weighted Average Grant Date Fair Value
Restricted stock units outstanding at December 31, 2016		30,739		$	7.91
Granted		—			—
Vested and released		(14,938	)		7.98
Forfeited and cancelled		(400	)		6.03
Restricted stock units outstanding at June 30, 2017		15,401		$	7.90