Condensed Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 69,245	$ 17,913
Accounts receivable	2,092	1,974
Prepaid expenses and other current assets	1,694	404
Total current assets	73,031	20,291
Property and equipment, net	3,506	1,780
Deferred offering costs	2,508
Other assets		62
Total assets	79,045	22,133
Current liabilities:
Accounts payable	775	675
Accrued expenses and other current liabilities	4,449	1,080
Amounts due to related parties	21	750
Deferred revenue	6,335	5,129
Notes payable	574	358
Total current liabilities	12,154	7,992
Deferred revenue, net of current portion	16,380	17,513
Notes payable, net of discount and current portion	903	1,166
Other liabilities	64
Total liabilities	$ 29,501	$ 26,671
Commitments and contingencies (Note 11)
Convertible preferred stock (Series A and B), $0.0001 par value; 44,683,824 shares authorized as of September 30, 2015 and 45,000,000 shares authorized as of December 31, 2014; 44,683,824 and 10,000,000 shares issued and outstanding as of September 30, 2015 and December 31, 2014, respectively; aggregate liquidation preference of $89,500 and $10,000 as of September 30, 2015 and December 31, 2014	$ 88,895	$ 9,653
Stockholders' deficit:
Common stock, $0.0001 par value; 68,000,000 shares authorized as of September 30, 2015 and 65,700,000 shares authorized as of December 31, 2014; 4,105,178 and 4,056,818 shares issued and outstanding as of September 30, 2015 and December 31, 2014, respectively	0	0
Additional paid-in capital	2,815	1,947
Accumulated deficit	(42,166)	(16,138)
Total stockholders' deficit	(39,351)	(14,191)
Total liabilities, convertible preferred stock and stockholders' deficit	$ 79,045	$ 22,133