Note 6 - Stockholders' Equity (Tables)

3 Months Ended

Mar. 31, 2022

Notes Tables

Schedule of Common Stock Reserved for Future Issuance [Table Text Block]

	March 31, 2022
Stock options outstanding		2,444,136
Restricted stock units		5,395
Shares available for grant under equity incentive plan		2,019,776
Warrants outstanding		5,109,501
		9,578,808