Stock Options and Stock-Based Employee Compensation (Tables)

6 Months Ended

Jun. 30, 2015

Stock Options and Stock-Based Employee Compensation [Abstract]

Weighted-average assumptions in estimating fair value of options

The fair value of each option award is estimated on the date of grant using the Black-Scholes option-pricing formula based on the following weighted average assumptions:

	June 30,
	2015	2014
Weighted average expected volatility	83%	100%
Weighted average expected term	5.6 years	5.4 years
Weighted average risk-free interest rate	1.5%	1.6%
Expected dividends	–	–

Employee stock-based compensation

The table below summarizes the total stock-based compensation expense included in the statements of operations for the periods presented:

(in thousands)	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2015		2014		2015		2014
Research & development	$	146	$	299	$	359	$	547
Selling, general & administrative		189		482		575		938
Total	$	335	$	781	$	934	$	1,485