Consolidated Balance Sheets - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 7,042,000	$ 53,349,000
Marketable securities	100,986,000
Prepaid expenses	1,491,000	792,000
Deferred offering costs		929,000
Other current assets	15,000	84,000
Total current assets	109,534,000	55,154,000
Restricted cash	84,000	0
Property and equipment, net	321,000	39,000
Total assets	109,939,000	55,193,000
Current liabilities:
Accounts payable (including related party amounts of $0 and $32 as of December 31, 2018 and 2017, respectively)	2,989,000	1,515,000
Accrued liabilities	2,727,000	3,987,000
Total current liabilities	5,716,000	5,502,000
Other liabilities	19,000
Total liabilities	5,735,000	5,502,000
Commitments and contingencies (see Note 12)
Stockholders’ equity (deficit):
Preferred stock, $0.0001 par value, 10,000,000 and no shares authorized as of December 31, 2018 and 2017, respectively; no shares issued and outstanding as of December 31, 2018 and 2017
Common stock, $0.0001 par value, 150,000,000 and 30,000,000 shares authorized as of December 31, 2018 and 2017, respectively; 28,055,344 and 5,659,089 shares issued and outstanding as of December 31, 2018 and 2017, respectively; 28,054,344 and 4,562,640 shares vested as of December 31, 2018 and 2017, respectively	3,000	1,000
Additional paid-in capital	175,635,000	1,849,000
Accumulated deficit	(71,393,000)	(33,779,000)
Other comprehensive loss	(41,000)
Total stockholders’ equity (deficit)	104,204,000	(31,929,000)
Total liabilities, redeemable convertible preferred stock and stockholders’ equity (deficit)	109,939,000	55,193,000
Series A Redeemable Convertible Preferred Stock
Redeemable convertible preferred stock:
Redeemable convertible preferred stock	0	41,674,000
Series B Redeemable Convertible Preferred Stock
Redeemable convertible preferred stock:
Redeemable convertible preferred stock	$ 0	$ 39,946,000