Note 15 - Share-based Compensation (Tables)

12 Months Ended

Dec. 31, 2024

Notes Tables

Share-Based Payment Arrangement, Option, Activity [Table Text Block]

						Weighted-
				Weighted-		average		Aggregate
				average		contractual		intrinsic value
	Amount			exercise price		life (years)		(in thousands)
Outstanding at January 1, 2023		2,516,924			3.95		7.68		6,917
Granted		2,130,007			5.81
Exercised		(65,264	)		2.29
Canceled / forfeited		(604,378	)		6.13
Outstanding at December 31, 2023		3,977,289			4.64		7.7		5,728
Granted		408,188			3.55
Outstanding at December 31, 2024		4,385,477		$	4.54		6.9	$	1,307
Options exercisable at December 31, 2024		2,907,296		$	4.59		6.7	$	1,135
Options vested or expected to vest at December 31, 2024		4,362,128		$	4.54		6.9	$	1,307

Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Year Ended December 31,
	2024			2023
Risk-free interest rate		4.09	%		3.82	%
Expected volatility		117.23	%		125.35	%
Expected term (in years)		5.6			5.8
Expected dividend yield		—	%		—	%

Share-Based Payment Arrangement, Cost by Plan [Table Text Block]

	Years Ended December 31,
	2024		2023
	(in thousands)
Research and development	$	489	$	327
Selling, general and administrative		1,913		3,134
Total stock-based compensation	$	2,402	$	3,461