Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	[1]
Current assets:
Cash and cash equivalents	$ 78,992	$ 71,064
Short-term investments	111,997	185,480
Receivable from collaboration partners	5,276	0
Prepaid expenses and other current assets	4,223	2,321
Amounts owed by a related party	0	83
Total current assets	200,488	258,948
Long-term investments	5,992	3,181
Property and equipment, net	10,011	11,107
Equity investment in related party	0	1,202
Restricted cash	203	203
Other long-term assets	263	284
Total assets	216,957	274,925
Current liabilities
Accounts payable	2,905	3,102
Accrued liabilities	9,662	6,023
Deferred revenue, current	7,000	6,250
Other current liabilities	1,490	1,560
Total current liabilities	21,057	16,935
Deferred revenue, noncurrent	13,772	16,984
Deferred rent	3,875	4,272
Other long-term liabilities	1,026	1,792
Total liabilities	39,730	39,983
Stockholders’ equity:
Preferred stock, $0.0001 par value, 10,000,000 shares authorized as of September 30, 2019 and December 31, 2018; no shares issued and outstanding as of September 30, 2019 and December 31, 2018	0	0
Common stock, $0.0001 par value, 400,000,000 shares authorized as of September 30, 2019 and December 31, 2018, respectively; 45,842,966 and 44,537,946 shares issued and outstanding as of September 30, 2019 and December 31, 2018 respectively	4	4
Additional paid-in capital	365,898	357,873
Accumulated deficit	(188,728)	(122,828)
Accumulated other comprehensive income (loss)	53	(107)
Total stockholders’ equity	177,227	234,942	[2]
Total liabilities, convertible preferred stock and stockholders’ equity	$ 216,957	$ 274,925

[1] The Condensed Consolidated Balance Sheet as of December 31, 2018 has been derived from the audited financial statements as of that date.

[2] The balances of December 31, 2018 and 2017 have been derived from the audited financial statements as of that date.