Amlitelimab phase 3 success in dermatitis at Sanofi (SNY)

Rhea-AI Filing Summary

Sanofi filed a Form 6-K to share a press release about its experimental medicine amlitelimab. The release states that amlitelimab met all primary and key secondary endpoints in the COAST 1 phase 3 study in adults and adolescents with atopic dermatitis. This means the treatment achieved the main goals and important additional measures set for this late-stage clinical trial, suggesting a broadly positive result for this patient group.

Insights

Biopharmaceutical clinical-trials analyst

Sanofi reports broadly positive phase 3 results for amlitelimab in atopic dermatitis.

The filing indicates that amlitelimab met all primary and key secondary endpoints in the COAST 1 phase 3 trial in adults and adolescents with atopic dermatitis. Hitting both primary and key secondary endpoints typically signals a robust, well-rounded efficacy outcome within the predefined trial design.

Because this is a phase 3 study, the result comes late in the development process, where data can influence future regulatory and commercial plans. The exact clinical effect size, safety profile, and regulatory path are not detailed here and would depend on the full press release and subsequent disclosures.

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 September 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 ☐

1

In September 2025, Sanofi published the press release attached hereto as Exhibit 99.1 which is incorporated herein by reference.

Exhibit Index

Exhibit No.		Description
Exhibit 99.1		Press Release dated September 4, 2025: Sanofi’s amlitelimab met all primary and key secondary endpoints in the COAST 1 phase 3 study in adults and adolescents with atopic dermatitis

2

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: September 4, 2025				SANOFI
				By		/s/ Alexandra Roger
						Name: Alexandra Roger
						Title: Head of Legal Corporate & Finance

3

FAQ

What did Sanofi (SNY) disclose in this Form 6-K?

Sanofi furnished a Form 6-K to provide a press release about amlitelimab. The release reports that amlitelimab met all primary and key secondary endpoints in the COAST 1 phase 3 study in atopic dermatitis.

What is the key news about amlitelimab for Sanofi (SNY)?

Sanofi reports that amlitelimab met all primary and key secondary endpoints in the COAST 1 phase 3 trial. This indicates the drug achieved its main and important additional goals in the atopic dermatitis study population.

Which patient group was included in Sanofi’s COAST 1 phase 3 study?

The COAST 1 phase 3 study evaluated amlitelimab in adults and adolescents with atopic dermatitis. The filing highlights that amlitelimab met all primary and key secondary endpoints specifically in this patient population.

When was the amlitelimab phase 3 press release issued by Sanofi (SNY)?

The attached press release about amlitelimab’s phase 3 results is dated September 4, 2025. Sanofi furnished this release as Exhibit 99.1 to the Form 6-K for the month of September 2025.

What exhibit is attached to Sanofi’s September 2025 Form 6-K?

The filing includes Exhibit 99.1, a press release dated September 4, 2025. That press release announces that amlitelimab met all primary and key secondary endpoints in the COAST 1 phase 3 study in atopic dermatitis.