Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 23,746	$ 21,897
Short-term investments	296,736	82,219
Restricted cash	194
Prepaid expenses and other current assets	3,921	1,910
Total current assets	324,597	106,026
Property and equipment, net	270	48
Other assets	108	48
Total assets	324,975	106,122
Current liabilities:
Accounts payable	1,445	440
Accrued compensation	2,624	1,225
Accrued research and development expenses	5,112	824
Other accrued liabilities	528	235
Total current liabilities	9,709	2,724
Long-term liabilities	166	216
Total liabilities	$ 9,875	$ 2,940
Commitments and contingencies (Note 7)
Stockholders’ equity:
Common stock—$0.0001 par value, 500,000,000 shares authorized as of December 31, 2015 and 2014; 28,458,807 and 19,692,937 shares issued and outstanding as of December 31, 2015 and 2014, respectively	$ 3	$ 2
Additional paid-in capital	413,725	144,169
Accumulated other comprehensive loss	(518)	(100)
Accumulated deficit	(98,110)	(40,889)
Total stockholders’ equity	315,100	103,182
Total liabilities and stockholders’ equity	$ 324,975	$ 106,122