AC Immune (ACIU) 6-KAC Immune Receives Second Milestone Payment Following Progress in Phase 2b Re𝜏ain Trial of ACI-35.030 in Preclinical Alzheimer’s Disease

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, 2024

Commission file number: 001-37891

AC IMMUNE SA

(Exact Name of Registrant as Specified in Its Charter)

EPFL Innovation Park
Building B
1015 Lausanne, Switzerland

(Address of Principal Executive Offices)

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

Form 20-F ☒     Form 40-F ☐

On September 17, 2024, AC Immune SA issued a press release announcing that it will receive the second Re𝜏ain-related milestone payment (CHF 24.6 million) under its agreement with Janssen Pharmaceuticals, Inc. (Janssen), a Johnson & Johnson company.

The milestone payment has been triggered by the rapid rate of prescreening in the potentially registrational Phase 2b Re𝜏ain trial investigating active-immunotherapy candidate ACI-35.030 (now called “JNJ-2056”) to treat preclinical (pre-symptomatic) Alzheimer’s disease (AD). With last December’s milestone payment, this brings the total milestone payments received for ACI-35.030 related to this trial to CHF 40 million.

This Report on Form 6-K (other than Exhibit 99.1 hereto) shall be deemed to be incorporated by reference into the registration statements on Form F-3 (File Nos. 333-227016, 333-249655, 333-255576 and 333-277940) and Form S-8 (File Nos. 333-213865, 333-216539 and 333-233019) of AC Immune SA and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished.

EXHIBIT INDEX

SIGNATURE

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.

Date: September 17, 2024