BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 5,154	$ 39,196
Marketable securities	72,828	75,401
Prepaid and other current assets	1,362	992
Total current assets	79,344	115,589
Property and equipment, net	1,462	2,180
Operating lease right-of-use asset	2,327	0
Other assets	513	463
Total assets	83,646	118,232
Current liabilities:
Accounts payable	2,448	1,998
Operating lease liability	878
Accrued and other liabilities	6,899	5,029
Total current liabilities	10,225	7,027
Operating lease liability	2,310
Other liabilities		869
Total liabilities	12,535	7,896
Commitments and contingencies (Note 12)
Stockholders' equity:
Preferred stock: $0.0001 par value; 10,000,000 shares authorized at December 31, 2019 and December 31, 2018; 0 shares issued and outstanding at December 31, 2019 and December 31, 2018
Common stock: $0.0001 par value; 290,000,000 shares authorized at December 31, 2019 and December 31, 2018; 27,953,233 and 29,323,930 shares issued and outstanding at December 31, 2019 and December 31, 2018, respectively	3	3
Additional paid-in capital	288,224	280,840
Accumulated other comprehensive income (loss)	29	(34)
Accumulated deficit	(217,145)	(170,473)
Total stockholders' equity	71,111	110,336
Total liabilities and stockholders' equity	$ 83,646	$ 118,232