AC Immune SA 6-K/A, filed Nov 23, 2020

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K/A

REPORTOF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR 15d-16 UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of November, 2020

Commission File Number: 001-37891

AC IMMUNE SA

(Exact name of registrant as specifiedin its charter)

EPFL Innovation Park

Building B

1015 Lausanne, Switzerland

(Address of principal executive office)

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

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):

EXPLANATORYNOTE AND INCORPORATION BY REFERENCE

This Form 6-K/A is being filed solely to incorporate by reference Exhibits 99.1 and 99.2 to this Form 6-K dated November 13, 2020 into the registrant’s Registration Statements on Form F-3 (File No. 333-224694, File No. 333-227016, and File No. 333-249655) and Form S-8 (File No. 333-233019). Accordingly, such exhibits shall be deemed to be incorporated by reference into the registration statements on Form F-3 (File No. 333-224694, File No. 333-227016 and File No. 333-249655) and Form S-8 (File No. 333-233019) of AC Immune SA and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished.

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: November 23, 2020

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