CONDENSED BALANCE SHEETS - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 67,268,340	$ 18,559,130
Short-term investments	276,942,151	78,912,297
Receivables	48,164	273,044
Prepaid expenses	1,552,085	751,255
Other assets	5,500,614	77,077
Total current assets	351,311,354	98,572,803
Property and equipment, net	1,556,314	2,182,399
Other noncurrent assets	2,336,637	7,067
Total assets	355,204,305	100,762,269
Current liabilities:
Accounts payable	1,095,064	376,394
Accrued wages and benefits	2,884,474	2,533,133
Accrued clinical trial expenses	1,512,346	689,985
Accrued expenses and other liabilities	2,182,883	946,668
Total current liabilities	7,674,767	4,546,180
Deferred revenue, net of current portion	332,945	731,944
Total liabilities	8,007,712	5,278,124
Stockholders’ equity:
Common stock: $0.001 par value, 100,000,000 shares authorized; 48,203,529 and 81,323,300 shares issued and outstanding at December 31, 2017 and September 30, 2018	81,323	48,204
Additional paid-in capital	688,527,897	404,454,909
Accumulated other comprehensive loss	(22,684)	(64,433)
Retained deficit	(341,389,943)	(308,954,535)
Total stockholders’ equity	347,196,593	95,484,145
Total liabilities and stockholders’ equity	$ 355,204,305	$ 100,762,269