Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2015

Our stock-based compensation expense for the three and nine months ended September 30 was as follows:


	Three months ended						Nine months ended
	September 30,						September 30,
	2015			2014			2015			2014
Research and development expense	$	781,791		$	188,357		$	2,063,499		$	414,246
General and administrative expense		644,451			320,454			2,023,211			1,129,331

Total stock-based compensation	$	1,426,242		$	508,811		$	4,086,710		$	1,543,577

Effect on basic and diluted net loss per share	$	(0.01	)	$	(0.01	)	$	(0.04	)	$	(0.03	)

A summary of our stock option activity for the three months ended September 30, 2015 is as follows:


	Number of options			Weighted-average exercise price ($) per share
Outstanding options at June 30, 2015		2,765,229			2.49
Granted¹		105,000			0.43
Exercised		—			—
Cancelled		(76,000	)		1.39

Outstanding options at September 30, 2015		2,794,229			2.44

A summary of changes in unvested options for the three months ended September 30, 2015 is as follows:


	Number of options			Weighted-average exercise price ($) per share		Weighted-average grant date fair value ($) per option
Unvested options at June 30, 2015		2,490,000			0.70		0.46
Granted		105,000			0.43		0.28
Vested		—			—		—
Cancelled		(75,000	)		0.71		0.49

Unvested options at September 30, 2015		2,520,000			0.69		0.45

A summary of changes in our restricted stock units for the three months ended September 30, 2015 is as follows:


	Number of RSUs			Weighted Average Grant Date Fair Value ($)
Outstanding at June 30, 2015		9,358,518			1.22
Granted²		100,000			0.41
Vested and exercised		(87,500	)		1.93
Cancelled		(108,500	)		1.14

Outstanding at September 30, 2015		9,262,518			1.20