CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Operating expenses:
Research and development	$ 1,685	$ 5,432	$ 3,467	$ 6,965
General and administrative	6,205	4,581	10,719	6,204
Impairment of in-process research and development	5,990	0	5,990	0
Transaction costs	0	0	0	5,765
Total operating expenses	13,880	10,013	20,176	18,934
Loss from operations	(13,880)	(10,013)	(20,176)	(18,934)
Other income (expense), net:
Loss on sale of NTN assets	0	(50)	0	(9,648)
Change in fair value of warrant liabilities	10,792	0	9,470	0
Loss on non-controlling investment	(296)	0	(911)	0
Other expense, net	(14)	(22)	(1,156)	(25)
Total other income (expense), net	10,482	(72)	7,403	(9,673)
Net loss	(3,398)	(10,085)	(12,773)	(28,607)
Series A preferred stock dividend	(8)	(8)	(8)	(8)
Net loss attributable to common stockholders	$ (3,406)	$ (10,093)	$ (12,781)	$ (28,615)
Net loss per common share - basic (in dollars per share)	$ (0.06)	$ (0.24)	$ (0.23)	$ (0.81)
Net loss per common share - diluted (in dollars per share)	$ (0.06)	$ (0.24)	$ (0.23)	$ (0.81)
Weighted average shares outstanding - basic (in shares)	58,805	42,448	56,230	35,187
Weighted average shares outstanding - diluted (in shares)	58,805	42,448	56,230	35,187