Consolidated Statements of Operations (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended		106 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014
Operating expenses:
Research and development	$ 2,385	$ 3,021	$ 8,678	$ 6,825	$ 34,471
General and administrative	1,800	2,386	5,317	6,505	28,444
Total operating expenses	4,185	5,407	13,995	13,330	62,915
Operating loss	(4,185)	(5,407)	(13,995)	(13,330)	(62,915)
Other income (expense):
Other income					383
Interest income	2	4	4	13	75
Interest expense	(35)	(34)	(102)	(95)	(1,370)
Modification of warrants				(765)	(765)
Derivatives gain (loss)	3,005		4,132	(18,871)	(27,278)
Other income (expense), net	2,972	(30)	4,034	(19,718)	(28,955)
Net loss	$ (1,213)	$ (5,437)	$ (9,961)	$ (33,048)	$ (91,870)
Net loss per share, basic (in dollars per share)	$ (0.01)	$ (0.07)	$ (0.12)	$ (0.46)	$ (2.09)
Net loss per share, diluted (in dollars per share)	$ (0.01)	$ (0.07)	$ (0.12)	$ (0.46)	$ (2.09)
Weighted average number of common shares outstanding, basic (in shares)	101,635,856	78,603,114	81,761,045	72,391,396	44,047,625
Weighted average number of common shares outstanding, diluted (in shares)	101,635,856	78,603,114	81,761,045	72,391,396	44,047,625