SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 3)

Cabaletta Bio, Inc.

(Name of Issuer)

Common Stock, par value $0.00001 per share

(Title of Class of Securities)

12674W109

(CUSIP Number)

03/31/2026

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

SCHEDULE 13G

CUSIP Number(s):

12674W109

Names of Reporting Persons

Cormorant Asset Management, LP

Check the appropriate box if a member of a Group (see instructions)

(a)

(b)

Sec Use Only

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 10,500,000.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 10,500,000.00

Aggregate Amount Beneficially Owned by Each Reporting Person

10,500,000.00

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in row (9)

9.03 %

Type of Reporting Person (See Instructions)

IA, PN

SCHEDULE 13G

CUSIP Number(s):

12674W109

Names of Reporting Persons

Bihua Chen

Check the appropriate box if a member of a Group (see instructions)

(a)

(b)

Sec Use Only

Citizenship or Place of Organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 10,500,000.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 10,500,000.00

Aggregate Amount Beneficially Owned by Each Reporting Person

10,500,000.00

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in row (9)

9.03 %

Type of Reporting Person (See Instructions)

HC, IN

SCHEDULE 13G

Item 1.

(a)

Name of issuer:

Cabaletta Bio, Inc.

(b)

Address of issuer's principal executive offices:

2929 Arch Street, Suite 600, Philadelphia, PA 19104

Item 2.

(a)

Name of person filing:

Cormorant Asset Management, LP Bihua Chen This statement is filed by (i) Cormorant Asset Management, LP, a Delaware limited partnership, and the investment adviser to certain funds (the "Cormorant Funds"), with respect to the shares directly held by the Cormorant Funds and (ii) Bihua Chen with respect to the shares directly held by the Cormorant Funds. The foregoing persons are hereinafter sometimes collectively referred to as the "Reporting Persons." The filing of this statement should not be construed as an admission that any of the foregoing persons or any Reporting Person is, for the purposes of Section 13 of the Act, the beneficial owner of the shares reported herein.

(b)

Address or principal business office or, if none, residence:

200 Clarendon Street, 52nd Floor Boston, MA 02116

(c)

Citizenship:

Cormorant Asset Management, LP - Delaware Bihua Chen - United States

(d)

Title of class of securities:

Common Stock, par value $0.00001 per share

(e)

CUSIP No.:

12674W109

Item 3.

If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:

(a)

Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);

(b)

Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);

(c)

Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);

(d)

Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);

(e)

An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);

(f)

An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);

(g)

A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);

(h)

A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);

(i)

A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);

(j)

A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),
please specify the type of institution:

(k)

Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).

Item 4.

Ownership

(a)

Amount beneficially owned:

10,500,000

(b)

Percent of class:

9.03%

(c)

Number of shares as to which the person has:

(i) Sole power to vote or to direct the vote:

(ii) Shared power to vote or to direct the vote:

10,500,000

(iii) Sole power to dispose or to direct the disposition of:

(iv) Shared power to dispose or to direct the disposition of:

10,500,000 The Reporting Persons' holdings reported herein reflect shares of common stock of the Issuer ("Common Stock") issuable upon the exercise of warrants (the "Warrants"). The Warrants are exercisable for up to 5,000,000 shares of Common Stock. The percentages reported herein with respect to the Reporting Persons' holdings are calculated based upon a statement in the Issuer's Annual Report on Form 10-K for the fiscal year ended December 31, 2025, as filed with the Securities and Exchange Commission on March 23, 2026, that there were 111,322,671 shares of Common Stock of the Issuer outstanding as of March 19, 2026.

Item 5.

Ownership of 5 Percent or Less of a Class.

Not Applicable

Item 6.

Ownership of more than 5 Percent on Behalf of Another Person.

If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required.

See Item 2. The Cormorant Funds have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the shares reported herein. Cormorant Global Healthcare Master Fund, LP, a Cormorant Fund, has the right to receive or the power to direct the receipt of dividends or the proceeds from the sale of more than 5% of the shares.

Item 7.

Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.

Not Applicable

Item 8.

Identification and Classification of Members of the Group.

Not Applicable

Item 9.

Notice of Dissolution of Group.

Not Applicable

Item 10.

Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Cormorant Asset Management, LP

Signature:	/s/ Bihua Chen
Name/Title:	Bihua Chen, Managing Member
Date:	05/15/2026

Bihua Chen

Signature:	/s/ Bihua Chen
Name/Title:	Bihua Chen
Date:	05/15/2026

Exhibit Information

Joint Filing Statement, incorporated by reference to the Joint Filing Statement included with the Schedule 13G filed by the Reporting Persons on August 14, 2025.

Amendment: SEC Form SCHEDULE 13G/A filed by Cabaletta Bio Inc.