Unaudited Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Current assets
Cash and cash equivalents	$ 165,604	$ 221,861
Available for sale securities	155,552	74,731
Income tax receivable	24,265	3,421
Due from Novartis Pharma AG	6	4,389
Prepaid expenses and other current assets	1,514	2,083
Total current assets	346,941	306,485
Available for sale securities	0	95,298
Property and equipment, net	3,174	3,466
Deferred tax assets	0	23,113
Other assets	470	489
Total assets	350,585	428,851
Current liabilities
Accrued research and development expenses	40,017	18,820
Accounts payable and accrued expenses	10,389	12,018
Deferred revenue	6,776	6,667
Total current liabilities	57,182	37,505
Deferred revenue, long-term	204,992	206,399
Royalty purchase liability	125,000	125,000
Total liabilities	387,174	368,904
Stockholders’ equity (deficit)
Preferred stock - $0.001 par value, 5,000,000 shares authorized, no shares issued or outstanding	0	0
Common stock - $0.001 par value, 200,000,000 shares authorized, 35,649,301 and 35,196,567 shares issued and outstanding at September 30, 2016 and December 31, 2015, respectively	36	35
Additional paid-in capital	496,210	465,924
Accumulated deficit	(532,676)	(405,539)
Accumulated other comprehensive loss	(159)	(473)
Total stockholders’ equity (deficit)	(36,589)	59,947
Total liabilities and stockholders’ equity (deficit)	$ 350,585	$ 428,851