Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
CURRENT ASSETS
Cash and cash equivalents	$ 90,095	$ 19,253
Marketable securities	56,178	52,696
Prepaid expenses and other current assets	3,516	2,556
Total current assets	149,789	74,505
Restricted cash	1,842	1,500
Property and equipment, net	5,642	2,385
Operating lease right-of-use assets	4,230	4,726
Other non-current assets	115	67
TOTAL ASSETS	161,618	83,183
CURRENT LIABILITIES
Accounts payable	2,254	3,154
Operating lease liabilities	319	351
Accrued and other current liabilities	13,870	14,854
Total current liabilities	16,443	18,359
Non-current operating lease liabilities	5,129	4,712
Other non-current liabilities	214	31
TOTAL LIABILITIES	21,786	23,102
Commitments and Contingencies (Note 14)
STOCKHOLDERS’ EQUITY
Preferred stock, $0.0001 par value; 10,000,000 shares authorized as ofDecember 31, 2020 and 2019; no shares issued and outstanding as ofDecember 31, 2020 and 2019
Common stock, $0.0001 par value; 500,000,000 shares authorized as of December 31, 2020 and 2019, 47,959,086 shares and 29,084,437 shares issued and outstanding as of December 31, 2020 and 2019, respectively	5	3
Additional paid-in capital	415,824	255,142
Accumulated other comprehensive income	11	51
Accumulated deficit	(276,008)	(195,115)
TOTAL STOCKHOLDERS’ EQUITY	139,832	60,081
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 161,618	$ 83,183