Condensed Consolidated Statements of Operations (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Revenue	$ 6,316,998	$ 6,428,840	$ 12,466,050	$ 12,766,562
Operating Expenses:
Research and development	4,918,655	5,984,098	9,624,012	11,804,472
General and administrative	2,780,099	3,409,372	5,728,580	8,349,026
Depreciation and amortization	76,448	116,690	162,358	234,319
Total operating expenses	7,775,202	9,510,160	15,514,950	20,387,817
Loss from operations	(1,458,204)	(3,081,320)	(3,048,900)	(7,621,255)
Other income (expense):
Interest income	4,819	3,381	7,807	6,535
Interest expense	(111,353)	(15,173)	(114,381)	(30,608)
Other income (expense)	519	(32,722)	53,434	(44,628)
Change in fair value of derivative instruments	823,809	688,221	(167,853)	3,176,686
Total other income (expense)	717,794	643,707	(220,993)	3,107,985
Net loss before income taxes	(740,410)	(2,437,613)	(3,269,893)	(4,513,270)
Income tax expense	(16,133)		(166,538)
Net loss	$ (756,543)	$ (2,437,613)	$ (3,436,431)	$ (4,513,270)
Basic and diluted net loss per share	$ (0.02)	$ (0.05)	$ (0.07)	$ (0.10)
Weighted average shares used in calculation of basic and diluted net loss per share	48,325,945	46,631,396	48,297,919	46,454,968