CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended		294 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013
Revenues:
Product sales and rentals			$ 11	$ 2	$ 1,909
Research and development agreements					2,105
Grants					9,901
Total revenues			11	2	13,915
Costs and expenses:
Cost of product sales and rentals			3	2	3,050
Research and development	2,575	6,147	11,789	20,012	228,519
Selling, general and administrative	1,066	2,138	4,259	6,131	96,857
Total costs and expenses	3,641	8,285	16,051	26,145	328,426
Loss from operations	(3,641)	(8,285)	(16,040)	(26,143)	(314,511)
Other income (expense):
Decrease in fair value of warrants	1,367	2,241	3,331	3,289	19,868
Other income					1,249
Interest income	4	14	12	40	10,834
Interest expense	(3)	(4)	(9)	(10)	(500)
Total other income	1,368	2,251	3,334	3,319	31,451
Net loss	$ (2,273)	$ (6,034)	$ (12,706)	$ (22,824)	$ (283,060)
Net loss per share attributable to common shareholders (Basic and Diluted) (in dollars per share)	$ (0.06)	$ (0.17)	$ (0.33)	$ (0.63)
Weighted average number of common shares outstanding (Basic and Diluted)	60,847	43,336	50,517	40,331