During the three month period ended March 31, 2025, in accordance with the terms of the Annual Increase of the Barinthus Biotherapeutics plc Award Plan 2021 (the “Plan”), the total number of ordinary shares available for issuance under the Plan increased by 4% of the Company’s issued and outstanding ordinary shares as of January 1, 2025.

For the three months ended March 31, 2025, the Company granted 1,349,768 options to employees and directors with a weighted average grant date fair value of $0.85 per share and a weighted average exercise price of $1.00 per share (March 31, 2024: granted 1,627,958 options, weighted average grant date fair value of $2.90 per share and a weighted average exercise price of $3.67 per share). For the three months ended March 31, 2025, 396,807 options (March 31, 2024: 70,946) were forfeited.

The fair value of each stock option issued to employees was estimated at the date of grant using the Black-Scholes model with the following weighted-average assumptions:


	Three months ended March 31,
	2025		2024
Expected volatility	114.1	%	108.8	%
Expected term (years)	6.0		6.0
Risk-free interest rate	4.4	%	4.0	%
Expected dividend yield	—	%	—	%

As of March 31, 2025, 8,133,504 options with a weighted average exercise price of $5.17 per share were outstanding (March 31, 2024: 7,645,076 options with a weighted average exercise price of $6.20 per share were outstanding). As of March 31, 2025, there was $2.9 million unrecognized compensation cost related to stock options, which is expected to be recognized over a weighted average period of 2.1 years.

Share based compensation expense is classified in the unaudited condensed consolidated statements of operations and comprehensive loss as follows (in thousands):


	Three months ended March 31,
		2025		2024
Research and development		$	68	$	712
General and administrative		400		903
Total		$	468	$	1,615