Form 6-K Altamira Therapeutics For: Jun 30

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 August 2025

Commission File Number: 001-36582

Altamira Therapeutics Ltd.

(Exact name of registrant as specified in its charter)

Clarendon House,

2 Church Street

Hamilton HM11, Bermuda

(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:

Form 20-F ☒        Form 40-F ☐

INCORPORATION BY REFERENCE

Exhibits 99.1 and 99.2 to this Report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form F-3 (Registration Numbers 333-249347, 333-264298, 333-267584, 333-272338, and 333-276427) and Form S-8 (Registration Numbers 333-232735, 333-252141, 333-278595 and 333-286392) of Altamira Therapeutics Ltd. (formerly Auris Medical Holding Ltd.) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished.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 99.3 to this Report on Form 6-K shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934 (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

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.

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