Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 15,960	$ 37,327
Short-term investments	98,103	122,416
Restricted cash	1,256	0
Contract and other receivables	10,021	274
Prepaid expenses	8,159	4,192
Other current assets	759	742
Total current assets	134,258	164,951
Property and equipment, net	5,400	3,568
Intangibles, net	1,081	1,150
Other assets	344	1,811
Total assets	141,083	171,480
Current liabilities:
Accounts payable	2,717	2,188
Accrued liabilities	6,329	4,402
Accrued compensation	2,392	2,108
Current portion of deferred revenue	1,194	3,097
Convertible note payable, at fair value	0	23,397
Total current liabilities	12,632	35,192
Deferred revenue, less current portion	2,065	3,252
Other long-term liabilities	2,308	1,022
Total liabilities	$ 17,005	$ 39,466
Commitments and Contingencies (Note 8)
Stockholders’ equity:
Common stock, $0.001 par value; 200,000,000 shares authorized, 52,669,266 and 48,944,530 shares issued and outstanding at December 31, 2015 and 2014, respectively	$ 53	$ 49
Additional paid-in capital	315,673	267,929
Accumulated other comprehensive loss	(133)	(197)
Accumulated deficit	(191,515)	(135,767)
Total stockholders’ equity	124,078	132,014
Total liabilities and stockholders’ equity	$ 141,083	$ 171,480