Quarterly report pursuant to Section 13 or 15(d)

Stock Plans (Tables)

Stock Plans (Tables)

9 Months Ended

Sep. 30, 2013

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

The following table summarizes the stock-based compensation expense recorded for awards under the stock option plans for the three and nine month periods ended September 30, 2013 and 2012:

	Three Months Ended September 30,				Nine months Ended September 30,
(in thousands, except per share amounts)	2013		2012		2013		2012
Research and development	$	11	$	148	$	367	$	878
General and administrative		10		217		289		1,355

Total stock-based compensation expenses	$	21	$	365	$	656	$	2,233

Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]

We use the Black-Scholes-Merton option-pricing model with the following assumptions to estimate the stock-based compensation expense for the three and nine month periods ended September 30, 2013 and 2012:

	Three Months Ended September 30,						Nine months Ended September 30,
	2013			2012			2013			2012
Weighted-average risk-free interest rate		0.9	%		0.9	%		0.9	%		0.9	%
Expected dividend payments		—			—			—			—
Expected holding period (years)¹		3.8			5.1			4.0			5.1
Weighted-average volatility factor²		1.05			1.74			1.48			1.74
Estimated forfeiture rates for options granted to management³		23	%		23	%		23	%		23	%
Estimated forfeiture rates for options granted to non-management³		41	%		41	%		41	%		41	%

(1)	Expected holding periods are based on the simplified method provided in Staff Accounting Bulletin No. 107 for “plain vanilla options.”
(2)	Weighted average volatility is based on the historical volatility of our common stock.
(3)	Estimated forfeiture rates are based on historical data.

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

The following table summarizes option activity for the nine month period ended September 30, 2013:

(in thousands, except per share amounts)	Options		Weighted Average Exercise Price		Weighted Average Remaining Option Term		Aggregate Intrinsic Value
Outstanding at January 1, 2013		6,842	$	1.33		6.65	$	722
Granted		—		—
Exercised		(75)		1.50
Expired or cancelled		—		—
Forfeited		—		—

Outstanding at September 30, 2013		6,767	$	1.32		5.97	$	—

Exercisable at September 30, 2013		6,753	$	1.32		5.97	$	—