Condensed Consolidated Statements of Operations and Comprehensive Loss (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	36 Months Ended
Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013
Expenses:
Research and development	$ 16,503	$ 8,150	$ 75,517
General and administrative	2,400	1,199	13,941
Acquired in-process research and development			15,130
Total expenses	18,903	9,349	104,588
Loss from operations	(18,903)	(9,349)	(104,588)
Interest income	34	20	244
Other expense			(1,661)
Net loss	(18,869)	(9,329)	(106,005)
Net loss per share applicable to common stockholders - basic and diluted (in dollars per share)	$ (0.66)	$ (13.59)	$ (14.80)
Weighted-average number of common shares used in net loss per share applicable to common stockholders - basic and diluted (in shares)	28,798	687	7,163
Comprehensive Loss	$ (18,869)	$ (9,329)	$ (106,005)

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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