CONSOLIDATED BALANCE SHEETS - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 70,063,242	$ 59,763,773
Incentive and tax receivables	14,613,969	3,444,620
Prepaid expenses and other current assets	2,378,812	3,747,087
Total current assets	87,056,023	66,955,480
Property and equipment, net	362,724	371,963
Right-of-use assets	345,849
Total assets	87,764,596	67,327,443
Current liabilities:
Accounts payable	4,740,981	4,461,567
Accrued expenses	7,073,506	5,264,215
Lease liabilities	243,677
Total current liabilities	12,058,164	9,725,782
Lease liabilities, long-term	109,689
Total liabilities	12,167,853	9,725,782
Stockholders' equity:
Preferred stock, $0.001 par value; 10,000,000 shares authorized; no shares issued or outstanding
Common stock, $0.001 par value; 200,000,000 shares authorized; 23,211,391 shares issued and outstanding at December 31, 2019 and 17,626,873 shares issued and outstanding at December 31, 2018	23,211	17,627
Additional paid-in capital	226,409,156	175,476,075
Accumulated deficit	(150,835,624)	(117,892,041)
Total stockholders' equity	75,596,743	57,601,661
Total liabilities and stockholders' equity	$ 87,764,596	$ 67,327,443