Share-based Compensation Plans (Tables)

12 Months Ended

Dec. 31, 2024

Share-Based Payment Arrangement [Abstract]

Schedule of share-based compensation expense

The following table provides share-based compensation reflected in the Company’s consolidated statements of operations and comprehensive loss for the years ended December 31, 2024 and 2023 (in thousands):

	Year Ended December 31,
	2024		2023
Research and development	$	91	$	421
General and administrative		534		646
	$	625	$	1,067

Schedule of stock option activity

A summary of stock option activity for the year ended December 31, 2024 is as follows:

						Weighted
				Weighted		Average		Average
				Average		Remaining		Intrinsic
	Number			Exercise		Contractual		Value (in
	of Options			Price		Term (Years)		thousands)
Outstanding as of December 31, 2023		291,368		$	189.09		4.6	$	—
Granted		55,849		$	3.30
Exercised		—		$	—
Cancelled or forfeited		(11,769	)	$	165.74
Outstanding as of December 31, 2024		335,448		$	158.98		4.7	$	—
Exercisable at December 31, 2024		258,558		$	199.26		3.5	$	—

Schedule of weighted-average assumptions used in estimating the fair value of the stock options

The weighted-average Black-Scholes assumptions used in estimating the fair value of the stock options granted by Cyclerion during the years ended December 31, 2024 and 2023 were as follows:

	Year ended December 31,
	2024			2023
Weighted average risk-free interest rate		3.64	%		3.47	%
Expected dividend yield		—			—
Expected option term (in years)		6.0			6.0
Expected stock price volatility		111.97	%		93.19	%

Summary of stock awards containing market conditions activity

A summary of stock awards containing market conditions activity for the year ended December 31, 2024 is as follows:

						Weighted
				Weighted		Average		Aggregate
				Average		Remaining		Intrinsic
	Number of			Exercise		Contractual		Value (in
	Options			Price		Term (years)		thousands)
Outstanding as of December 31, 2023		7,500		$	40.20		5.9	$	—
Granted		—			—		—		—
Exercised		—			—		—		—
Cancelled or forfeited		(7,500	)	$	40.20		—	$	—
Outstanding as of December 31, 2024		—		$	—		—	$	—
Exercisable at December 31, 2024		—		$	—		—	$	—

Summary of RSA activity

A summary of RSA activity for the years ended December 31, 2024 is as follows:

				Weighted Average
	Number			Grant Date
	of Shares			Fair Value
Unvested as of December 31, 2023		170,937		$	2.28
Granted		65,000			3.35
Vested		(71,763	)		2.61
Forfeited		—			—
Unvested as of December 31, 2024		164,174		$	2.55