Annual report pursuant to Section 13 and 15(d)

Consolidated Statements of Stockholders' Equity (Deficit)

Consolidated Statements of Stockholders' Equity (Deficit) (USD $)	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]
Balance at Dec. 31, 2011	$ 21,131,747us-gaap_StockholdersEquity	$ 10	$ 95,399	$ 266,393,645	$ (245,357,307)
Balance, shares at Dec. 31, 2011		10,083	95,398,961
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issued restricted stock	455		455
Issued restricted stock, shares			455,000
Canceled forfeited restricted stock	(596)		(601)	5
Canceled forfeited restricted stock, shares			(600,500)
Issued stock upon exercise of stock options, net	743,295		1,226	742,069
Issued stock upon exercise of stock options, net, shares	1,225,271		1,225,271
Canceled stock to pay employee tax obligations	(100,875)		(37)	(100,838)
Canceled stock to pay employee tax obligations, shares			(37,500)
Issued stock to 401(k) plan	50,272		17	50,255
Issued stock to 401(k) plan, shares	17,390		17,390
Issued stock upon exercise of warrants, net	1,978,601		6,020	1,972,581
Issued stock upon exercise of warrants, net, shares			6,020,000
Issued stock for payment of sublicense fee	1,146,000		300	1,145,700
Issued stock for payment of sublicense fee, shares	300,000		300,000
Conversion of Series B preferred stock to common stock, net		(2)	7,014	(7,012)
Conversion of Series B preferred stock to common stock, shares		2,145	7,014,150
Conversion of Series C preferred stock to common stock		(1)	3,226	(3,225)
Conversion of Series C preferred stock to common stock, shares		1,000	3,226,000
Effect of change in terms of warrants	496,671			496,671
Recovery of shareholder short swing profits	45,473			45,473
Stock compensation expense	2,304,118			2,304,118
Preferred stock dividends	(43,333)us-gaap_DividendsPreferredStock				(43,333)
Net loss	(29,157,204)us-gaap_NetIncomeLoss				(29,157,204)
Balance at Dec. 31, 2012	(1,405,376)us-gaap_StockholdersEquity	7	113,019	273,039,442	(274,557,844)
Balance, shares at Dec. 31, 2012		6,938	113,018,772
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issued stock in connection with public offerings, net of costs	38,131,472		14,205	38,117,267
Issued stock in connection with public offerings, net of costs, shares			14,205,770
Issued restricted stock	74		74
Issued restricted stock, shares			73,500
Canceled forfeited restricted stock	(29)		(29)
Canceled forfeited restricted stock, shares			(29,250)
Issued stock upon exercise of stock options, net	(9,161)		40	(9,201)
Issued stock upon exercise of stock options, net, shares	39,649		39,649
Canceled stock to pay employee tax obligations	(610,556)		(194)	(610,362)
Canceled stock to pay employee tax obligations, shares			(194,077)
Issued stock to 401(k) plan	66,777		22	66,755
Issued stock to 401(k) plan, shares	22,126		22,126
Issued stock upon exercise of warrants, net	6,161,332	2	3,000	6,158,330
Issued stock upon exercise of warrants, net, shares		2,365	3,000,000
Conversion of Series B preferred stock to common stock, net	0	(1)	5,682	(5,681)
Conversion of Series B preferred stock to common stock, shares		1,738	5,682,933
Issued stock for payment of milestone fee	166,000		100	165,900
Issued stock for payment of milestone fee, shares	100,000		100,000
Issued warrants in connection with debt issuance	967,115			967,115
Issued warrants in connection with public offering	(7,686,046)			(7,686,046)
Stock compensation expense	2,908,269			2,908,269
Net loss	(42,699,458)us-gaap_NetIncomeLoss				(42,699,458)
Balance at Dec. 31, 2013	(4,009,587)us-gaap_StockholdersEquity	8	135,919	313,111,788	(317,257,302)
Balance, shares at Dec. 31, 2013		7,565	135,919,423
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issued restricted stock	380		380
Issued restricted stock, shares			380,250
Canceled forfeited restricted stock	(300)		(300)	0
Canceled forfeited restricted stock, shares			(300,000)
Issued stock upon exercise of stock options, net	(51,369)		300	(51,669)
Issued stock upon exercise of stock options, net, shares	299,360		299,360
Canceled stock to pay employee tax obligations	(8,819)		(6)	(8,813)
Canceled stock to pay employee tax obligations, shares			(6,582)
Issued stock to 401(k) plan	100,043		36	100,007
Issued stock to 401(k) plan, shares	36,455		36,455
Issued stock upon exercise of warrants, net	7,686,773		3,843	7,682,930
Issued stock upon exercise of warrants, net, shares			3,843,223
Issued stock in payment of Board retainers	89,375		68	89,307
Issued stock in payment of Board retainers, shares			67,710
Conversion of Series B preferred stock to common stock, net	0	(4)	9,960	(9,956)
Conversion of Series B preferred stock to common stock, shares		3,046	9,960,420
Issued warrants in connection with debt issuance	464,991			464,991
Recovery of shareholder short swing profits	17,554			17,554
Stock compensation expense	1,634,162			1,634,162
Net loss	(35,726,669)us-gaap_NetIncomeLoss				(35,726,669)
Balance at Dec. 31, 2014	$ (29,803,466)us-gaap_StockholdersEquity	$ 4	$ 150,200	$ 323,030,301	$ (352,983,971)
Balance, shares at Dec. 31, 2014		4,519	150,200,259