Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 120,133	$ 150,456
Short-term marketable securities	281,848	265,198
Accounts receivable	1,867	4,846
Prepaid expenses and other current assets	9,723	4,004
Total current assets	413,571	424,504
Long-term marketable securities	6,479	15,391
Property and equipment, net	5,548	3,986
Goodwill	8,766	8,469
Intangible assets, net	30,471	29,400
Other assets	3,177	75
Total assets	468,012	481,825
Current liabilities:
Accounts payable	5,226	5,086
Accrued clinical trial and manufacturing expenses	10,614	5,522
Accrued expenses and other liabilities	10,207	5,412
Deferred revenue	15,046	15,046
Total current liabilities	41,093	31,066
Deferred rent	932
Contingent consideration	3,594	3,750
Deferred revenue	174,276	178,037
Deferred tax liabilities	7,840	7,350
Total liabilities	$ 227,735	$ 220,203
Commitments and contingencies (Note 7)
Stockholders’ equity:
Preferred stock, $0.0001 par value; 10,000,000 shares authorized at March 31, 2016 and December 31, 2015; and zero shares issued and outstanding at March 31, 2016 and December 31, 2015
Common stock, $0.0001 par value; 300,000,000 shares authorized March 31, 2016 and December 31, 2015; and 64,559,772 and 63,587,833 shares issued and outstanding at March 31, 2016 and December 31, 2015	$ 6	$ 6
Additional paid-in capital	369,009	362,807
Accumulated other comprehensive income (loss)	941	(339)
Accumulated deficit	(129,679)	(100,852)
Total stockholders’ equity	240,277	261,622
Total liabilities and stockholders’ equity	$ 468,012	$ 481,825