Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Current assets
Cash and cash equivalents	$ 197,945	$ 91,060
Short-term investments	35,717	45,502
Prepaid expenses and other current assets	4,028	1,865
Total current assets	237,690	138,427
Long-term investments	0	13,808
Furniture, fixtures and equipment, net	7,857	3,816
Other assets, net	2,707	3,076
Total assets	248,254	159,127
Current liabilities
Accounts payable and other current liabilities	18,820	16,565
Interest payable	551	551
Total current liabilities	19,371	17,116
Convertible notes, net of discounts	123,539	123,236
Total liabilities	142,910	140,352
Commitments and contingencies (Note 13)
Stockholders’ equity
Preferred stock, $0.001 par value; 15,000,000 shares authorized as of December 31, 2016 and December 31, 2015; None issued and outstanding	0	0
Common stock, $0.001 par value; 150,000,000 shares authorized as of December 31, 2016 and December 31, 2015; 33,458,607 and 26,458,495 shares issued and outstanding as of December 31, 2016 and December 31, 2015, respectively	33	26
Additional paid-in capital	422,002	236,492
Accumulated other comprehensive loss	(68)	(179)
Accumulated deficit	(316,623)	(217,564)
Total stockholders’ equity	105,344	18,775
Total liabilities and stockholders’ equity	$ 248,254	$ 159,127