Cabaletta Bio, Inc. Annual report pursuant to Section 13 and 15(d)

Annual report pursuant to Section 13 and 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

Fair Value Measurements - Schedule of Debt Securities Classified as Available-for-Sale Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 241,210	$ 106,594
Gross Unrealized Gains	43	0
Gross Unrealized Losses	(4)	(47)
Fair value	241,249	106,547
Money Market Funds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	180,124
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Fair value	180,124
Cash and Cash Equivalents [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	193,234	81,607
Gross Unrealized Gains	4	0
Gross Unrealized Losses	0	0
Fair value	193,238	81,607
Cash [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	743
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Fair value	743
U.S. Treasury securities - original maturity less than three months
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	12,367
Gross Unrealized Gains	4
Gross Unrealized Losses	0
Fair value	12,371
Government securities - due in one year or less
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	47,976	24,987
Gross Unrealized Gains	39	0
Gross Unrealized Losses	(4)	(47)
Fair value	$ 48,011	$ 24,940

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