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

Quarterly report [Sections 13 or 15(d)]

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 ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2025	Dec. 31, 2024
Number of Shares
Number of Shares, Beginning Balance	11,231,148
Number of Shares, Granted	2,869,050
Number of shares, Forfeited/Cancelled	(33,993)
Number of Shares, Ending Balance	14,066,205	11,231,148
Number of Shares, Options Exercisable	6,448,912
Weighted Average Exercise Price
Weighted Average Exercise Price, Beginning Balance	$ 10.63
Weighted Average Exercise Price, Granted	1.7
Weighted Average Exercise Price, Forfeited/Cancelled	15.18
Weighted Average Exercise Price, Ending Balance	8.8	$ 10.63
Weighted Average Exercise Price, Options Exercisable	$ 9.06
Weighted Average Remaining Contractual Term (years)
Term (years)	7 years 8 months 12 days	7 years 4 months 24 days
Weighted Average Remaining Contractual Term (years), Options Exercisable	6 years 1 month 6 days
Aggregate Intrinsic Value
Aggregate Intrinsic Value, Beginning Balance	$ 989
Aggregate Intrinsic Value, Ending Balance	270	$ 989
Aggregate Intrinsic Value, Options Exercisable	$ 267

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Share based compensation arrangement by share based payment award options outstanding aggregate intrinsic value.

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Share based compensation arrangement by share based payment award options outstanding weighted average remaining contractual term.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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