Cabaletta Bio, Inc. Quarterly report [Sections 13 or 15(d)]

Quarterly report [Sections 13 or 15(d)]

Common Stock (Tables)

Common Stock (Tables)

9 Months Ended

Sep. 30, 2025

A summary of stock option activity is presented below:


	Number of Shares			Weighted Average Exercise Price (1)		Weighted Average Remaining Contractual Term (years)		Aggregate Intrinsic Value
Outstanding as of January 1, 2025		11,231,148		$	10.63		7.4	$	989
Granted		3,133,050			1.71
Exercised		(13,334	)		1.01			$	9
Forfeited/Cancelled		(732,691	)		7.63
Outstanding as of September 30, 2025		13,618,173		$	8.75		7.2	$	2,913
Options Exercisable at September 30, 2025		7,479,760		$	9.40		5.9	$	1,016

(1) The weighted average exercise prices and aggregate intrinsic values in this table will not reflect the impact of the May 2025 repricing until the retention period is complete in May 2026.

Schedule of Assumptions Used to Estimate Fair Value of Stock Options

The fair value of each award is estimated using Black-Scholes based on the following assumptions:


	Nine months ended September 30,
	2025	2024
Risk-free interest rate	3.94%—4.46%	3.43%—4.60%
Expected term	5.5 years—6.1 years	5.5 years—6.2 years
Expected volatility	112%—118%	104%—110%
Expected dividend yield	0%	0%

Summary of Stock-Based Compensation

The Company has recorded stock-based compensation in the accompanying statements of operations as follows:


	Three months ended September 30,				Nine months ended September 30,
	2025		2024		2025		2024
Research and development	$	3,317	$	2,769	$	9,272	$	7,325
General and administrative		2,498		2,481		7,409		6,729
Total	$	5,815	$	5,250	$	16,681	$	14,054