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 2021

001-36203

(Commission File Number)

CAN-FITE BIOPHARMA LTD.

(Exact name of Registrant as specified in its charter)

10 Bareket Street

Kiryat Matalon, P.O. Box 7537

Petach-Tikva 4951778, Israel

(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 þ       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): ____

This Report on Form 6-K (including exhibits thereto) is hereby incorporated by reference into the registrant’s Registration Statements on Form S-8 (File No. 333-227753) and Form F-3 (File Nos. 333-195124, 333-236064, 333-237443 and 333-249063), to be a part thereof from the date on which this report is submitted, to the extent not superseded by documents or reports subsequently filed or furnished.

On December 20, 2021, Can-Fite BioPharma Ltd. (the “Company”) entered into a warrant exercise agreement (the “Exercise Agreement”) with an institutional investor (the “Holder”) who is the holder of certain existing warrants (the “Warrants”) to purchase the Company’s ordinary shares, par value NIS 0.25 per share (the “Ordinary Shares”), represented by American Depositary Shares (“ADSs”) issued by the Company in a registered direct offering consummated in August 2021. Pursuant to the Exercise Agreement, the Holder agreed to exercise in cash its Warrants to purchase up to an aggregate of 150,000,000 Ordinary Shares represented by 5,000,000 ADSs having an exercise price of $2.00 per ADS, at an exercise price of $2.00 per ADS, for gross proceeds to the Company of $10.0 million, prior to deducting placement agent fees and offering expenses.

The Company intends to use the net proceeds from the offering for working capital, including for the launch of the Phase II study in NASH and Phase III liver cancer study, as well as other general corporate purposes.

Under the Exercise Agreement, the Company also agreed to issue to the Holder new unregistered warrants to purchase up to 180,000,000 Ordinary Shares represented by 6,000,000 ADSs (the “Private Placement Warrants”). The Private Placement Warrants will be immediately exercisable, will expire five years following the effectiveness of an initial resale registration statement registering the ADSs issuable upon the exercise of the warrants, and have an exercise price of $2.00 per ADS, subject to adjustment as set forth therein.

The Private Placement Warrants, the Wainwright Warrant (as defined hereunder) and the ADSs issuable thereunder are being offered and sold pursuant to an exemption from the registration requirements under Section 4(a)(2) of the Securities Act of 1933, as amended (the “Securities Act”) and Rule 506 of Regulation D promulgated thereunder. The investor has represented that it is an accredited investor, as that term is defined in Regulation D. The offer and sale of the foregoing securities is being made without any form of general solicitation or advertising. The Private Placement Warrants, the Wainwright Warrant and the ADSs issuable thereunder have not been registered under the Securities Act or applicable state securities laws. Accordingly, the Private Placement Warrants, the Wainwright Warrant and the ADSs issuable thereunder may not be offered or sold in the United States except pursuant to an effective registration statement or an applicable exemption from the registration requirements of the Securities Act and such applicable state securities laws.

The ADSs and the Ordinary Shares issuable upon the exercise of the Warrants issued in August 2021 are registered pursuant to a registration statement on Form F-1 (File No. 333-259085) which became effective by the SEC on September 1, 2021. This Report shall not constitute an offer to sell or the solicitation to buy nor shall there be any sale of the ADSs or warrants in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.

The foregoing summary of the terms of the Exercise Agreement and Private Placement Warrants are subject to, and qualified in their entirety by reference to, the form of Warrant Exercise Agreement and form of Private Placement Warrants with the Holder, which are filed as Exhibits 10.1 and 10.2 to this Report on Form 6-K, respectively, and are incorporated herein by reference.

In connection with the Exercise Agreement, the Company engaged H.C. Wainwright & Co., LLC to act as the Company’s exclusive placement agent. Pursuant to an Engagement Agreement dated December 20, 2021 (the “Engagement Agreement”), the Company agreed to pay the Placement Agent a cash placement fee equal to 7.0% of the aggregate number of ADSs placed in the offering, plus a management fee equal to 1.0% of the gross proceeds raised in the offering and a non-accountable expense allowance of $75,000. In addition, the Company agreed to issue to the Placement Agent warrants exercisable for 7.0% of the aggregate number of ADSs placed in the offering, on the same terms as the Private Placement Warrants (the “Wainwright Warrant”). The foregoing summary of the terms of the Wainwright Warrant is subject to, and qualified in their entirety by reference to, the form of Wainwright Warrant, which is identical to the form of Private Placement Warrants filed as Exhibit 10.2 to this Report on Form 6-K and is incorporated herein by reference.

Exhibit Index

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.

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