Statement of Changes in Beneficial Ownership (Form 4)

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b). Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person * RTW INVESTMENTS, LP 2. Issuer Name and Ticker or Trading Symbol ALLURION TECHNOLOGIES, INC. [ALUR] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director __X__ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) 40 10TH AVENUE, 7TH FLOOR 3. Date of Earliest Transaction (Month/Day/Year) 07/21/2026 (Street) NEW YORK, NY 10014 4. If Amendment, Date Original Filed (Month/Day/Year) 6. Individual or Joint/Group Filing (Check Applicable Line) ___ Form filed by One Reporting Person _X_ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock, $0.0001 par value per share 07/21/2026 J(1) 209,254 D (1) 0 I See footnotes(2)(3) Common Stock, $0.0001 par value per share 07/21/2026 J(4) 161,807 D (4) 0 I See footnotes(2)(5) Common Stock, $0.0001 par value per share 07/21/2026 J(6) 19,934 D (6) 0 I See footnotes(2)(7) Common Stock, $0.0001 par value per share 07/21/2026 J(8) 1,771 D (8) 0 I See footnotes(2)(9)

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Pre-Funded Warrant (Right to Buy)

$0.0001

07/21/2026

J(1)

209,254

(10)

(10)

Common Stock

209,254

(1)

209,254

I

See Footnotes(2)(3)

Pre-Funded Warrant (Right to Buy)

$0.0001

07/21/2026

J(4)

161,807

(10)

(10)

Common Stock

161,807

(4)

161,807

I

See footnotes(2)(5)

Pre-Funded Warrant (Right to Buy)

$0.0001

07/21/2026

J(6)

19,934

(10)

(10)

Common Stock

19,934

(6)

19,934

I

See footnotes(2)(7)

Pre-Funded Warrant (Right to Buy)

$0.0001

07/21/2026

J(8)

1,771

(10)

(10)

Common Stock

1,771

(8)

1,771

I

See footnotes(2)(9)

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
RTW INVESTMENTS, LP 40 10TH AVENUE, 7TH FLOOR NEW YORK, NY 10014		X
WONG RODERICK 40 10TH AVENUE, 7TH FLOOR NEW YORK, NY 10014		X

Signatures

/s/ Roderick Wong, M.D. - For RTW Investments, L.P., By: Roderick Wong, M.D., Managing Partner		07/23/2026
**Signature of Reporting Person		Date
/s/ Roderick Wong, M.D.		07/23/2026
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	On July 21, 2026, RTW Master Fund, Ltd. ("Master Fund") entered into an Exchange Agreement with the Issuer pursuant to which the Master Fund exchanged, for no additional consideration, 209,254 shares of the Issuer's Common Stock for a pre-funded warrant exercisable for up to 209,254 shares of the Issuer's Common Stock at an exercise price of $0.0001 per share (a "Pre-Funded Warrant").
(2)	RTW Investments, LP (the "Adviser") manages certain funds that directly hold the securities reported herein, including the Master Fund, RTW Innovation Master Fund, Ltd. ("RTW Innovation"), RTW Biotech Opportunities Operating Ltd. ("RTW Biotech Fund") and other funds or accounts managed by the Adviser (each, an "Other RTW Fund"). Roderick Wong, M.D. serves as the Managing Partner and Chief Investment Officer of the Adviser. Each Reporting Person disclaims beneficial ownership of the securities reported on this Form 4 except to the extent of its or his pecuniary interest, if any, therein, and this report shall not be deemed to be an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or for any other purpose.
(3)	Held directly by Master Fund.
(4)	On July 21, 2026, RTW Innovation entered into an Exchange Agreement with the Issuer pursuant to which the RTW Innovation exchanged, for no additional consideration, 161,807 shares of the Issuer's Common Stock for a Pre-Funded Warrant exercisable for 161,807 shares of the Issuer's Common Stock.
(5)	Held directly by RTW Innovation.
(6)	On July 21, 2026, RTW Biotech Fund entered into an Exchange Agreement with the Issuer pursuant to which the RTW Biotech Fund exchanged, for no additional consideration, 19,934 shares of the Issuer's Common Stock for a Pre-Funded Warrant exercisable for 19,934 shares of the Issuer's Common Stock.
(7)	Held directly by RTW Biotech Fund.
(8)	On July 21, 2026, RTW Innovation entered into an Exchange Agreement with the Issuer pursuant to which Other RTW Fund exchanged, for no additional consideration, 1,771 shares of the Issuer's Common Stock for a Pre-Funded Warrant exercisable for 1,771 shares of the Issuer's Common Stock.
(9)	Held by an Other RTW Fund.
(10)	The Pre-Funded Warrant has no expiration date and is exercisable immediately. Notwithstanding the foregoing, the holder shall not be entitled to exercise the Pre-Funded Warrant to the extent that it would cause the aggregate number of shares of Common Stock beneficially owned by the holder, together with its Attribution Parties (as defined in the Pre-Funded Warrant), to exceed 9.99% of the total number of issued and outstanding shares of Common Stock of the Issuer following such exercise.
Remarks: On June 18, 2026, the Issuer effected a 1-for-15 reverse stock split. The share counts herein reflect the reverse stock split.

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