Sanofi (SNY) files Form 6-K with updates on tolebrutinib in MS

Rhea-AI Filing Summary

Sanofi filed a Form 6-K to furnish two December 15, 2025 press releases related to its multiple sclerosis candidate tolebrutinib. One press release provides an update on the regulatory submission for tolebrutinib in non-relapsing secondary progressive multiple sclerosis, and the other provides an update on tolebrutinib in primary progressive multiple sclerosis. Both press releases are incorporated into this report by reference.

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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FAQ

What does Sanofi (SNY) report in this Form 6-K?

The Form 6-K states that in December 2025 Sanofi published two press releases about tolebrutinib in multiple sclerosis, which are attached as Exhibits 99.1 and 99.2 and incorporated by reference.

What is the focus of Exhibit 99.1 in Sanofi’s (SNY) December 2025 Form 6-K?

Exhibit 99.1 is a press release dated December 15, 2025 titled “Sanofi provides update on tolebrutinib regulatory submission in non-relapsing secondary progressive multiple sclerosis.”

What is the focus of Exhibit 99.2 in Sanofi’s (SNY) December 2025 Form 6-K?

Exhibit 99.2 is a press release dated December 15, 2025 titled “Sanofi provides update on tolebrutinib in primary progressive multiple sclerosis.”

Does this Sanofi (SNY) Form 6-K include financial results?

No, this Form 6-K simply furnishes and incorporates by reference two press releases regarding updates on tolebrutinib in specific multiple sclerosis indications.

Who signed Sanofi’s (SNY) December 2025 Form 6-K?

The report was signed on behalf of Sanofi by Alexandra Roger, Head of Legal Corporate & Finance, dated December 15, 2025.