Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
CURRENT ASSETS:
Cash and cash equivalents	$ 90,690	$ 104,055
Prepaid expenses and other current assets	1,983	2,415
Total current assets	92,673	106,470
Property and equipment, net	71	52
Operating lease right-of-use assets	946	318
Other assets	687	647
TOTAL ASSETS	94,377	107,487
CURRENT LIABILITIES:
Accrued and other liabilities	7,913	7,148
Accounts payable	1,548	2,205
Total current liabilities	9,461	9,353
Operating lease liabilities	650	175
TOTAL LIABILITIES	10,111	9,528
Commitments and Contingencies (Note 7)
STOCKHOLDERS’ EQUITY:
Preferred stock, $0.001 par value; 10,000,000 shares authorized as of June 30, 2021 and December 31, 2020; nil shares issued and outstanding as of June 30, 2021 and December 31, 2020
Common stock, $0.001 par value; 500,000,000 shares authorized as of June 30, 2021 and December 31, 2020; 12,358,517 and 11,128,484 shares issued and outstanding as of June 30, 2021 and December 31, 2020	12	11
Additional paid-in capital	971,388	944,537
Accumulated deficit	(887,134)	(846,589)
TOTAL STOCKHOLDERS’ EQUITY	84,266	97,959
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 94,377	$ 107,487