Cabaletta Bio, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 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

Fair Value Measurements - Schedule of Debt Securities Classified as Available-for-Sale Investments (Details)

v3.24.1.1.u2

Fair Value Measurements - Schedule of Debt Securities Classified as Available-for-Sale Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 223,883	$ 241,210
Gross Unrealized Gains	0	43
Gross Unrealized Losses	(38)	(4)
Fair value	223,845	241,249
Money Market Funds Included in Cash and Cash Equivalents
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	175,293	193,234
Gross Unrealized Gains	0	4
Gross Unrealized Losses	0	0
Fair value	175,293	193,238
Government securities - due in one year or less
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	48,590	47,976
Gross Unrealized Gains	0	39
Gross Unrealized Losses	(38)	(4)
Fair value	48,552	48,011
Corporate Note Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost		12,367
Gross Unrealized Gains		4
Gross Unrealized Losses		0
Fair value		12,371
Money Market Funds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	173,956	180,124
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair value	173,956	180,124
Cash [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	1,337	743
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair value	$ 1,337	$ 743

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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