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)

v3.24.3

Fair Value Measurements - Schedule of Debt Securities Classified as Available-for-Sale Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 183,011	$ 241,210
Gross Unrealized Gains	1	43
Gross Unrealized Losses	0	(4)
Fair value	183,012	241,249
Cash
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	611	743
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair value	611	743
Money Market Funds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	169,997	180,124
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair value	169,997	180,124
U.S. Treasury Securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	12,403	47,976
Gross Unrealized Gains	1	39
Gross Unrealized Losses	0	(4)
Fair value	12,404	48,011
Money Market Funds Included in Cash and Cash Equivalents
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	170,608	193,234
Gross Unrealized Gains	0	4
Gross Unrealized Losses	0	0
Fair value	$ 170,608	193,238
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

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