# EDGAR Filing Document

**Accession Number:** 0001759138
**File Stem:** 0001193125-25-179840
**Filing Date:** 2025-8
**Character Count:** 2358
**Document Hash:** a1cc906cab2c3ae5254111f8545ed70b
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-25-179840.hdr.sgml**: 20250915

**ACCESSION NUMBER**: 0001193125-25-179840

**CONFORMED SUBMISSION TYPE**: CORRESP

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20250813

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Cabaletta Bio, Inc.
- **CENTRAL INDEX KEY:** 0001759138
- **STANDARD INDUSTRIAL CLASSIFICATION:** BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** CORRESP

**BUSINESS ADDRESS:**
- **STREET 1:** 2929 ARCH STREET
- **STREET 2:** SUITE 600
- **CITY:** PHILADELPHIA
- **STATE:** PA
- **ZIP:** 19104
- **BUSINESS PHONE:** (267) 759-3100

**MAIL ADDRESS:**
- **STREET 1:** 2929 ARCH STREET
- **STREET 2:** SUITE 600
- **CITY:** PHILADELPHIA
- **STATE:** PA
- **ZIP:** 19104

Cabaletta Bio, Inc.

2929 Arch Street, Suite 600

Philadelphia, Pennsylvania 19104

August 13, 2025

**Via EDGAR Transmission** 

Securities and Exchange Commission

Division of Corporation Finance

100 F Street, N.E.

Washington, D.C. 20549

Attention: Joshua Gorsky

Re: Cabaletta Bio, Inc.: Registration Statement on Form S-3 filed August 7, 2025

(File No. 333-289339)

Ladies and Gentlemen:

Pursuant to Rule 461 under the Securities Act of 1933, as amended (the "**Act**"), Cabaletta Bio, Inc. (the "**Company**") hereby requests that the effective date of the above-referenced registration statement (the "**Registration Statement**") be accelerated to August 15, 2025, at 4:01 pm Eastern Time, or as soon thereafter as practicable, unless we or our outside counsel, Goodwin Procter LLP, request by telephone that such Registration Statement be declared effective at some other time. In making this acceleration request, the Company acknowledges that it is aware of its responsibilities under the Act.

If you have any questions regarding this request, please contact Finnbarr Murphy, Esq. of Goodwin Procter LLP at (212) 459-7257.

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| |
|:---|
| Sincerely, |
| CABALETTA BIO, INC. |
| /s/ Steven Nichtberger, M.D. |
| Steven Nichtberger, M.D.<br> President and Chief Executive Officer |

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cc: Michael Gerard, Esq., Cabaletta Bio, Inc.

Mitchell S. Bloom, Esq., Goodwin Procter LLP

Finnbarr Murphy, Esq., Goodwin Procter LLP