CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 36,308	$ 115,069
Marketable securities	121,140	60,576
Accounts receivable	25,000
Prepaid expenses and other current assets	2,719	2,296
Total current assets	185,167	177,941
Property and equipment, net	4,171	3,190
Operating lease right-of-use asset	4,447
Restricted cash	2,498	205
Other long-term assets	98
Total assets	196,381	181,336
Current liabilities:
Accounts payable	1,130	3,303
Accrued expenses	9,610	7,157
Deferred rent		16
Operating lease liability	1,135
Loan payable		424
Deferred revenue	20,923	20,209
Other current liabilities	16	14
Total current liabilities	32,814	31,123
Long-term portion of deferred rent		871
Long-term portion of operating lease liability	4,168
Other long-term liabilities	9	24
Long-term portion of deferred revenue	46,489	42,695
Total liabilities	83,480	74,713
Commitments and contingencies (Note 12)
Stockholders' equity:
Preferred stock, $0.001 par value; 10,000,000 shares authorized at December 31, 2019 and December 31, 2018; no shares issued and outstanding at December 31, 2019 and December 31, 2018
Common stock, $0.001 par value; 150,000,000 shares authorized and 29,792,922 shares issued and outstanding as of December 31, 2019; 150,000,000 shares authorized and 26,217,701 shares issued and outstanding as of December 31, 2018	30	26
Additional paid-in capital	270,682	213,453
Accumulated other comprehensive income (loss)	37	(8)
Accumulated deficit	(157,848)	(106,848)
Total stockholders' equity	112,901	106,623
Total liabilities and stockholders' equity	$ 196,381	$ 181,336