Annual report pursuant to Section 13 and 15(d)

Stock Plans and Stock-Based Compensation (Tables)

Stock Plans and Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

The following table summarizes stock option activity:


	Shares Subject to Outstanding Options			Weighted- Average Exercise Price of Options		Weighted- Average Remaining Contractual Term (Years)		Aggregate Intrinsic Value (in thousands)
Outstanding as of December 31, 2014		991,010		$	6.09
Options granted		845,703			9.00
Options exercised		—			0
Options forfeited		(15,631	)		4.75
Options expired		(16,999	)		12.31

Outstanding as of December 31, 2015		1,804,083		$	7.41		8.24	$	—

Vested and expected to vest as of December 31, 2015		1,757,991		$	7.38		8.22	$	—

Exercisable as of December 31, 2015		783,856		$	6.28		7.81	$	—

Summary of Stock Options Outstanding

The following table summarizes information about stock options outstanding as of December 31, 2015:


	Options Outstanding				Options Exercisable
Exercise Price	Number of Shares		Weighted- Average Remaining Contractual Term (Years)		Number of Shares
$1.98 – $4.77		108,483		8.95		65,800
$5.00		858,442		7.57		617,070
$5.23		10,000		8.65		3,333
$5.90		18,000		9.29		18,000
$6.85		12,000		8.73		4,500
$7.00		77,000		8.28		32,083
$7.99		6,500		8.36		2,594
$10.00 – $10.49		710,203		8.93		37,021
$238.50		3,455		0.73		3,455

		1,804,083		8.24		783,856

Estimated Weighted-Average Grant Date Fair Value

The following table presents the weighted-average assumptions the Company used in the Black-Scholes valuation model to derive the grant date fair value-based measurements of employee and director stock options and the resulting estimated weighted-average grant date fair-value-based measurements per share:


	Year Ended December 31,
	2015			2014
Weighted-average assumptions:
Expected term		6.1 yrs			6.0 yrs
Expected volatility		78	%		90	%
Risk-free interest rate		1.65	%		2.02	%
Expected dividend yield		0	%		0	%
Weighted-average grant date fair value per share	$	6.13		$	4.06

Summary of Stock-Based Compensation Expense

Employee and director stock-based compensation expense recorded was as follows (in thousands):


	Year Ended December 31,
	2015		2014
Research and development	$	823	$	332
General and administrative		1,643		952

Total	$	2,466	$	1,284