Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 39,594	$ 51,033
Marketable securities	73,161
Prepaid expenses	1,676	785
Other current assets	894	508
Total current assets	115,325	52,326
Restricted cash		13
Property and equipment, net	4,660	1,540
Other assets	282	343
Total assets	120,267	54,222
Current liabilities:
Accounts payable	662	547
Accrued liabilities	2,345	911
Deferred rent, current	343
Other liabilities, current	152	26
Total current liabilities	3,502	1,484
Deferred rent, noncurrent	2,638	494
Total liabilities	6,140	1,978
Redeemable convertible preferred stock, $0.001 par value, zero and 75,533,240 shares authorized as of September 30, 2018 and December 31, 2017, respectively; zero and 12,263,126 shares issued and outstanding as of September 30, 2018 and December 31, 2017, respectively		77,931
Stockholders' equity (deficit):
Common stock, $0.001 par value, 125,000,000 and 96,000,000 shares authorized as of September 30, 2018 and December 31, 2017, respectively; 19,108,221 and 948,578 shares issued and outstanding as of September 30, 2018 and December 31, 2017, respectively	19	5
Preferred stock, $0.001 par value, 10,000,000 and zero shares authorized as of September 30, 2018 and December 31, 2017, respectively; zero shares issued and outstanding as of September 30, 2018 and December 31, 2017
Additional paid-in capital	157,681	447
Accumulated other comprehensive loss	(160)	(111)
Accumulated deficit	(43,413)	(26,028)
Total stockholders' equity (deficit)	114,127	(25,687)
Total liabilities, redeemable convertible preferred stock and stockholders' equity (deficit)	$ 120,267	$ 54,222