Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 100,650	$ 98,679
Prepaid expenses and other current assets	4,988	3,506
Income tax receivable	116	115
Other receivables	0	26,149
Total current assets	105,754	128,449
Non-current assets:
Property and equipment, net	75	335
Right-of-use asset	636	249
Total non-current assets	711	584
Total assets	106,465	129,033
Current liabilities:
Accounts payable	149	244
Accrued expenses	5,555	5,898
Current portion of lease liability	349	319
Total current liabilities	6,053	6,461
Long-term liabilities:
Royalty obligation payable to Iowa Economic Development Authority	6,000	6,000
Lease liability	288	0
Total long-term liabilities	6,288	6,000
Total liabilities	12,341	12,461
Stockholders' equity:
Undesignated preferred stock, $0.01 par value: Authorized shares - 5,000,000 at September 30, 2021 and December 31, 2020; issued and outstanding shares - 0 at September 30, 2021 and December 31, 2020	0	0
Common stock, $0.01 par value: Authorized shares - 75,000,000 at September 30, 2021 and December 31, 2020; issued shares - 8,366,819 and 8,305,269 at September 30, 2021 and December 31, 2020, respectively, and outstanding shares - 8,357,391 and 8,305,269 at September 30, 2021 and December 31, 2020, respectively	83	83
Treasury stock, at cost, 9,428 and 0 shares at September 30, 2021 and December 31, 2020, respectively	(114)	0
Additional paid-in capital	184,935	182,480
Accumulated deficit	(90,780)	(65,991)
Total stockholders' equity	94,124	116,572
Total liabilities and stockholders' equity	$ 106,465	$ 129,033