[6-K] Sanofi Current Report (Foreign Issuer)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of December 2025

Commission File Number: 001-31368

SANOFI

(Translation of registrant’s name into English)

46, avenue de la Grande Armée, 75017 Paris, FRANCE

(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F ☒  Form 40-F ☐

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In December 2025, Sanofi published the press releases attached hereto as Exhibits 99.1 and 99.2 which are incorporated herein by reference.

Exhibit Index

Exhibit No.		Description
Exhibit 99.1		Press Release dated December 15, 2025: Sanofi provides update on tolebrutinib regulatory submission in non-relapsing secondary progressive multiple sclerosis
Exhibit 99.2		Press Release dated December 15, 2025: Sanofi provides update on tolebrutinib in primary progressive multiple sclerosis

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Dated: December 15, 2025						SANOFI
				By		/s/ Alexandra Roger
						Name: Alexandra Roger
						Title: Head of Legal Corporate & Finance

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