Stockholders' Equity and Share-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2026

Stockholders' Equity and Share-Based Compensation

Schedule of share-based compensation expense category

	Three Months Ended June 30,				Six Months Ended June 30,
(in thousands)	2026		2025		2026		2025
Research and development	$	49	$	248	$	191	$	492
General and administrative		476		675		890		1,289
	$	525	$	923	$	1,081	$	1,781

Schedule of stock option activity plan

				Weighted
		Weighted		average
		average		remaining
	Number of	exercise price		contractual
	shares	per share		term (years)
Outstanding at January 1, 2026	658,973	$	44.20	7.1
Granted	254,744		7.00
Exercised	—		—
Forfeited	(186,173)		11.52
Expired	(79,923)		73.84
Outstanding at June 30, 2026	647,621	$	35.30	6.2
Vested and exercisable at June 30, 2026	423,601	$	48.76	4.6
Vested or expected to vest at June 30, 2026	647,621	$	35.30	6.2

Schedule of weighted average assumptions applied to options

	Six Months Ended June 30,
	2026		2025
Expected volatility	93.4	%	93.7	%
Risk‑free interest rate	4.0	%	4.1	%
Expected term	5.5	years	5.9	years
Expected dividend yield	—		—

Schedule of activity related to restricted stock unit

			Weighted average
	Number of shares		grant date fair value
Unvested balance at January 1, 2026	50,000	$	10.52
Granted	—		—
Vested	(35,000)		11.70
Forfeited	—		—
Unvested balance at June 30, 2026	15,000	$	11.70