Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Assets, Current
Cash and cash equivalents	$ 67,032	$ 31,309
Marketable securities	136,961	163,028
Prepaid Expense and Other Assets, Current	1,484	1,557
Total Current Assets	205,477	195,894
Property, Plant and Equipment, Net	3,603	3,234
Deposits and other non-current assets	735	321
Marketable securities		30,008
Total Assets	209,815	229,457
Liabilities, Current
Accounts Payable	454	612
Accrued expenses	5,049	3,430
Deferred rent, current portion		300
Deferred revenue, current portion	14,257	19,589
Total current liabilities	19,760	23,931
Deferred rent, net of current portion	1,390	1,015
Deferred revenue, net of current portion	32,927	35,393
Other non-current liabilities	34	44
Total Liabilities	54,111	60,383
Stockholders' Equity Attributable to Parent
Common stock, $0.001 par value: 120,000,000 shares authorized at June 30, 2016 and December 31, 2015; 25,276,258 and 24,930,979 shares issued and outstanding at June 30, 2016 and December 31, 2015, respectively	25	25
Additional Paid in Capital	221,964	219,122
Accumulated other comprehensive gain	60	(251)
Accumulated deficit	(66,345)	(49,822)
Total stockholders’ deficit	155,704	169,074
Total liabilities, redeemable convertible preferred stock and stockholders’ deficit	$ 209,815	$ 229,457