STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Research contract revenue	$ 1,969	$ 272
Operating expenses:
Research and development, including costs of research contracts	10,199	74,249
General and administrative	3,810	4,250
Total operating expenses	14,009	78,499
Loss from operations	(12,040)	(78,227)
Other income (expense), net	21	(4)
Net loss	$ (12,019)	$ (78,231)
Net loss per share - basic and diluted	$ (0.09)	$ (0.69)
Weighted average common shares outstanding used to compute net loss per share - basic and diluted	130,157,927	113,410,250