Cabaletta Bio, Inc. Annual report [Section 13 and 15(d), not S-K Item 405]

Annual report [Section 13 and 15(d), not S-K Item 405]

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Common Stock - Summary of Stock Option Activity (Details)

v3.25.1

Common Stock - Summary of Stock Option Activity (Details) - Employee Stock Option - 2019 Plan - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Number of Shares
Number of Shares, Beginning Balance	8,141,035
Number of Shares, Granted	3,476,700
Number of Shares, Exercised	(210,695)
Number of shares, Forfeited/Cancelled	(175,892)
Number of Shares, Ending Balance	11,231,148	8,141,035
Number of Shares, Options Exercisable	5,642,705
Weighted Average Exercise Price
Weighted Average Exercise Price, Beginning Balance	$ 8.28
Weighted Average Exercise Price, Granted	16.13
Weighted Average Exercise Price, Exercised	6.79
Weighted Average Exercise Price, Forfeited/Cancelled	15.04
Weighted Average Exercise Price, Ending Balance	10.63	$ 8.28
Weighted Average Exercise Price, Options Exercisable	$ 7.92
Weighted Average Remaining Contractual Term (years)
Weighted Average Remaining Contractual Term (years), Options Outstanding	7 years 4 months 24 days	7 years 7 months 6 days
Weighted Average Remaining Contractual Term (years), Options Exercisable	6 years 1 month 6 days
Aggregate Intrinsic Value
Aggregate Intrinsic Value, Beginning Balance	$ 117,384
Aggregate Intrinsic Value, Exercised	2,889
Aggregate Intrinsic Value, Ending Balance	989	$ 117,384
Aggregate Intrinsic Value, Options Exercisable	$ 966

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