Form 8-K

8-K — Onconetix, Inc.

Accession: 0001213900-26-047577

Filed: 2026-04-24

Period: 2026-04-20

CIK: 0001782107

SIC: 2834 (PHARMACEUTICAL PREPARATIONS)

Item: Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Item: Financial Statements and Exhibits

Documents

8-K — ea0287604-8k_onconetix.htm (Primary)

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8-K — CURRENT REPORT

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UNITED

STATES

SECURITIES

AND EXCHANGE COMMISSION

WASHINGTON,

D.C. 20549

FORM

8-K

CURRENT

REPORT

Pursuant

to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date

of Report (Date of earliest event reported): April 24, 2026 (April 20, 2026)

Onconetix, Inc.

(Exact

name of registrant as specified in its charter)

Delaware

001-41294

83-2262816

(State

or other Jurisdiction

of Incorporation)

(Commission

File Number)

(IRS

Employer

Identification No.)

201 E. Fifth Street, Suite 1900

Cincinnati,

Ohio

45202

(Address

of Principal Executive Offices)

(Zip

Code)

Registrant’s

telephone number, including area code: (513) 620-4101

(Former

name or former address, if changed since last report.)

Check

the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under

any of the following provisions:

☐

Written communications

pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐

Soliciting material pursuant

to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐

Pre-commencement communications

pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐

Pre-commencement communications

pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities

registered pursuant to Section 12(b) of the Act:

Title

of each class

Trading

Symbol(s)

Name

of each exchange on which registered

Common Stock, par value $0.00001 per share

ONCO

The

Nasdaq Stock Market LLC

Indicate

by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405

of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging

growth company ☒

an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying

with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item

5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of

Certain Officers

Resignation of Andrew Oakley and Thomas Meier

as Directors; Elections of Sammy Dorf as Chairman of the Board

Effective on April 20, 2026,

Andrew Oakley and Thomas Meier notified the Board of Directors (the “Board”) of Onconetix, Inc, a Delaware corporation

(the “Company”), of their resignation from the Board. As a result of their resignation from the Board and effective

as of the date mentioned herein, Mr. Oakley has also resigned from his position as Chairman of the Board and his service on the Audit

Committee, Compensation Committee and the Nominating and Corporate Governance Committee, and Mr. Meier has also resigned from his service

on the Compensation Committee.

Mr.

Oakley’s and Mr. Meier’s departures from the Board were not the result of any disagreement with management or the Board

on any matter relating to the Company’s operations, policies or practices.

Effective

on April 23, 2026, the Board has appointed Sammy Dorf, an existing member of the Board, as Chairman of the Board. In connection with

Mr. Dorf’s election as Chairman, the Compensation Committee of the Board has agreed to compensate Mr. Dorf $20,000 per year, payable on

a quarterly basis, commencing on the date of his election.

Election

of Josh Epstein

Effective

as of April 23, 2026, the Board elected Josh Epstein to serve as a member of the Board and a member of the Audit Committee, Compensation

Committee and as the chair of the Nominating and Corporate Governance Committee. Mr. Epstein will be a Class II director and will serve

for a term expiring at the Company’s 2026 annual meeting of stockholders.

Mr.

Epstein is a senior executive and legal professional with more than 20 years of experience across the energy, mining, technology, healthcare,

cannabis, blockchain, gaming, and autonomous-systems industries. Since December 2025, he has served in a Corporate Development, Capital

Markets and Legal role at Mariana Minerals Co., a mining technology company developing AI-powered software and autonomous operating systems

designed to optimize mineral processing, mine operations, and capital deployment across producing assets. In that capacity, he advises

the C-suite on corporate development, capital markets strategy, mergers and acquisitions, partnership structuring, and transaction execution.

Since October 2025, Mr. Epstein has served as a Board Member of SRx Health Solutions, Inc. (NYSE American: SRXH).

From November of 2024 to December of 2025, Mr. Epstein was the head of

Corporate Development and on the Board of Managers for Lisbon Valley Mining Co., overseeing all capital markets, M&A, partnership,

and other transactional activities for the producing copper mine in Southeast Utah. Formerly, from March 2021 to November 2024, Mr. Epstein

was a consultant to JJR Private Capital, a Florida and Toronto-based private equity firm founded in 2003. Previously, Mr. Epstein served

as the CEO and Director of Socati Corp., a vertically integrated manufacturer of ingredients and consumer products for global cannabinoid

and wellness markets. Prior to Socati, Mr. Epstein served as President and COO of Nuuvera Inc., an international wellness and medical

cannabis company founded in 2016 that later listed on the Toronto Stock Exchange–V and sold to Tilray Inc. (NASDAQ: TLRY) (formerly

Aphria Inc.) in 2018. Mr. Epstein was previously a Partner with FastForward Innovations Ltd., an early-stage venture capital firm where

he oversaw investments and divestitures of the firm’s portfolio companies in the United States, Canada, the United Kingdom, Germany,

Israel and China. Mr. Epstein began his career as an attorney with the international law firm Baker Botts, LLP, where his practice focused

on mergers and acquisitions, venture capital and securities offerings. Mr. Epstein holds a B.A (English, Honors Program) and B.B.A. (Finance)

from the University of Texas, a JD from the University of Texas School of Law, where he graduated with Honors and as a member of the Texas

Law Review, and an MBA from the Acton School of Business in Austin, Texas, where he was Valedictorian of his class.

For

his service on the Board, Mr. Epstein will receive compensation consistent with that of other non-employee directors.

Mr.

Epstein has no family relationships with any of the Company’s directors or executive officers, and he is not a party to, and does

not have any direct or indirect material interest in any transaction requiring disclosure under Item 404(a) of Regulation S-K. There

are no arrangements or understandings between Mr. Epstein and any other persons pursuant to which he was selected as a member of the

Board.

Item

9.01. Financial Statements and Exhibits

(d)

Exhibits

Exhibit

No.

Description

104

Cover Page Interactive

Data File (embedded within the Inline XBRL document)

SIGNATURE

Pursuant

to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its

behalf by the undersigned hereunto duly authorized.

ONCONETIX, INC.

Date: April 24, 2026

By:

/s/ David

Allan White

Name:

David Allan White

Title:

Chief Executive Officer

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Entity File Number

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Entity Registrant Name

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Entity Central Index Key

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Entity Tax Identification Number

83-2262816

Entity Incorporation, State or Country Code

Entity Address, Address Line One

201 E. Fifth Street

Entity Address, Address Line Two

Suite 1900

Entity Address, City or Town

Cincinnati

Entity Address, State or Province

Entity Address, Postal Zip Code

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City Area Code

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Local Phone Number

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Pre-commencement Tender Offer

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Title of 12(b) Security

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Trading Symbol

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Security Exchange Name

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