Form 8-K

8-K — Onconetix, Inc.

Accession: 0001213900-26-099524

Filed: 2026-09-14

Period: 2026-09-11

CIK: 0001782107

SIC: 2834 (PHARMACEUTICAL PREPARATIONS)

Item: Entry into a Material Definitive Agreement

Item: Regulation FD Disclosure

Item: Financial Statements and Exhibits

Documents

8-K — ea0305157-8k_onconetix.htm (Primary)

EX-10.1 — FORM OF GRID PROMISSORY NOTE, DATED SEPTEMBER 11, 2026, BY AND BETWEEN REALBOTIX, LLC AND ONCONETIX, INC (ea030515701ex10-1.htm)

EX-10.2 — FORM OF GUARANTY OF PAYMENT, DATED SEPTEMBER 11, 2026, BY REALBOTIX CORP. IN FAVOR OF ONCONETIX, INC (ea030515701ex10-2.htm)

EX-99.1 — PRESS RELEASE, DATED SEPTEMBER 14, 2026 (ea030515701ex99-1.htm)

XML — IDEA: XBRL DOCUMENT (R1.htm)

8-K — CURRENT REPORT

8-K (Primary)

Filename: ea0305157-8k_onconetix.htm · Sequence: 1

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0001782107

2026-09-11

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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):

September 11, 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)

(I.R.S. 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 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 ☒

If 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 1.01. Entry into a Material Definitive Agreement.

On September 11, 2026, Onconetix,

Inc. (the “Company”) entered into a Grid Promissory Note (the “Note”) with Realbotix, LLC (“Realbotix”),

pursuant to which the Company agreed to make available to Realbotix loans in an aggregate principal amount of up to $5.0 million, of which

$2.5 million was advanced on September 11, 2026. The proceeds of the loans may be used by Realbotix for general corporate and working

capital purposes. The Note is an unsecured obligation of Realbotix. The Note matures on September 11, 2027 and does not bear interest

prior to the earlier of the closing of the transactions contemplated by the Share Exchange Agreement, dated February 11, 2026 (the “Share

Exchange Agreement”), or the termination of the Share Exchange Agreement. If the Share Exchange Agreement is terminated, interest

will accrue on the outstanding principal balance at a rate of 12% per annum until the Note is paid.

On February 11, 2026, the

Company entered into the Share Exchange Agreement with Realbotix, Realbotix Corp. and Simulacra Corporation, pursuant to which, subject

to the terms and conditions thereof, the Company will acquire all of the issued and outstanding equity interests of Realbotix in exchange

for newly issued shares of the Company’s common stock (the “Realbotix Transaction”). The consummation of the

Realbotix Transaction is subject to customary closing conditions, including the Company having at least $12.5 million in Net Cash at

closing.

Upon the closing of the transactions

contemplated by the Share Exchange Agreement, the Note and all obligations thereunder will automatically be cancelled and discharged,

and the Net Cash at Closing under the Share Exchange Agreement will be increased by $500,000 plus the aggregate principal amount then

outstanding under the Note.

Realbotix’s obligations

under the Note are guaranteed by Realbotix Corp. pursuant to a Guaranty of Payment, dated September 11, 2026 (the “Guaranty”).

The foregoing descriptions of the Note and the Guaranty do not purport to be complete and are qualified in their entirety by reference

to the Note and the Guaranty, copies of which are filed as Exhibits 10.1 and 10.2, respectively, to this Current Report on Form 8-K and

incorporated herein by reference.

Item 7.01. Regulation FD Disclosure.

On September 14, 2026, Onconetix,

Inc. issued a press release regarding the loan to Realbotix, LLC described in Item 1.01 above. A copy of the press release is furnished

as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

The information contained

in this Item 7.01, including Exhibit 99.1, is being furnished and shall not be deemed “filed” for purposes of Section 18 of

the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that

section, nor shall such information be deemed incorporated by reference into any filing under the Securities Act of 1933, as amended,

or the Exchange Act, except as expressly set forth by specific reference in such filing.

Item 9.01. Exhibits.

Exhibit No.

Description

10.1

Form

of Grid Promissory Note, dated September 11, 2026, by and between Realbotix, LLC and Onconetix, Inc.

10.2

Form of Guaranty

of Payment, dated September 11, 2026, by Realbotix Corp. in favor of Onconetix, Inc.

99.1

Press Release, dated September 14, 2026.

104

Cover Page Interactive Data File (embedded within the Inline XBRL document).

SIGNATURE

Pursuant to the requirements of the Securities

Exchange Act of 1934, the registrant has caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Onconetix, Inc.

Dated: September 14, 2026

By:

/s/ David A. White

David A. White

Chief Executive Officer

EX-10.1 — FORM OF GRID PROMISSORY NOTE, DATED SEPTEMBER 11, 2026, BY AND BETWEEN REALBOTIX, LLC AND ONCONETIX, INC

EX-10.1

Filename: ea030515701ex10-1.htm · Sequence: 2

Exhibit 10.1

NONE OF THE

SECURITIES REPRESENTED HEREBY HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “1933 ACT”), OR

ANY U.S. STATE. SECURITIES LAWS, AND, UNLESS SO REGISTERED, MAY NOT BE OFFERED OR SOLD, DIRECTLY OR INDIRECTLY, IN THE UNITED STATES (AS

DEFINED HEREIN) OR TO U.S. PERSONS EXCEPT IN ACCORDANCE WITH THE PROVISIONS OF REGULATIONS UNDER THE 1933 ACT, PURSUANT TO AN EFFECTIVE

REGISTRATION STATEMENT UNDER THE 1933 ACT, OR PURSUANT TO AN AVAILABLE EXEMPTION FROM, OR IN A TRANSACTION SUBJECT TO, THE REGISTRATION

REQUIREMENTS OF THE 1933 ACT AND IN EACH CASE ONLY IN ACCORDANCE WITH APPLICABLE STATE SECURITIES LAW. IN ADDITION, HEDGING TRANSACTIONS

INVOLVING THE SECURITIES MAY NOT BE CONDUCTED UNLESS IN COMPLIANCE WITH THE 1933 ACT. “UNITED STATES” AND “U.S. PERSON”

ARE AS DEFINED BY REGULATION S UNDER THE 1933 ACT.

GRID

PROMISSORY NOTE

Principal Amount: Up to $5,000,000.00

Issuance Date: September 11, 2026

Maturity Date: September 11, 2027

FOR VALUE RECEIVED,

on demand as permitted herein, Realbotix, LLC, a Delaware limited liability company (the "Borrower" or the “Company”)

whose business address is 40 Temperance St, Suite 3200, Toronto, ON M5H 0B4, promises to pay to the order of Onconetix, Inc., a Delaware

corporation (the "Lender"), at its offices 1180 201 E. Fifth Street, Suite 1900, Cincinnati, Ohio 45202, or at

such other place as the Lender may designate in writing, the aggregate outstanding principal amount of loans (the "Loans")

outstanding hereunder, as conclusively evidenced on the grid attached hereto as Schedule I (the “Grid”).

Realbotix Corp., a Ontario corporation (the “Guarantor”) at is offices 40 Temperance St, Suite 3200, Toronto,

ON M5H 0B4, hereby absolutely, unconditionally and irrevocably guarantees the full and punctual payment and performance of all obligations

of the Borrower under this Note as set forth in Section 3 hereof and the Guaranty executed by Guarantor. Unless this Note is cancelled

in accordance with Section 8, all unpaid principal, together with any then accrued but unpaid interest and any other amounts payable hereunder,

shall be due and payable on the Maturity Date.

1. Use

of Proceeds. The proceeds of the Loans shall be used by Borrower for general corporate and working capital purposes. The proceeds

may not be used for distributions to members or repayment of affiliate or insider indebtedness.

2. Conclusiveness

of Grid. The Loans represented by this Note are such that, prior to the Maturity Date, the Borrower may borrow, from time to time

hereunder up to an aggregate amount not to exceed the sum of Five Million U.S. Dollars ($5,000,000.00) (the “Maximum Principal

Amount”) to be funded from time to time upon written notice to the Lender (each amount borrowed, an “Advance”

and each such funding date, a “Funding Date”), provided that the Funding Conditions shall have been satisfied.

The Grid shall, in the absence of manifest error, constitute conclusive proof of the amounts and dates of all advances, outstanding principal

amounts and repayment of principal in respect to the Loans.

3. Guaranty.

The Guarantor hereby absolutely, unconditionally and irrevocably guarantees to the Lender the due and punctual payment and performance

when due, whether at stated maturity, by acceleration or otherwise, of all obligations of the Borrower under this Note (collectively,

the “Guaranteed Obligations”). This guaranty constitutes a guaranty of payment and performance and not of collection.

The obligations of the Guarantor hereunder shall be primary, absolute and unconditional and shall not be subject to any reduction, limitation,

impairment or termination for any reason. This guaranty shall remain in full force and effect until all Guaranteed Obligations have been

indefeasibly paid and performed in full or are otherwise discharged in accordance with Section 8. The terms of the Guarantor’s liability

for the Guaranteed Obligations shall be governed by the terms of the form of Guaranty annexed hereto as Exhibit A.

4. Funding Conditions. The Advances shall be funded on the Funding Date, provided

that the following conditions shall have been satisfied (or waived in writing by Lender):

a. Borrower and Guarantor, as applicable, shall have duly executed and delivered the Note and this Note

shall remain in full force and effect;

b. The Share Exchange Agreement dated as of February 11, 2026 between Lender, Borrower, Guarantor and Simulacra

Corporation, a Delaware corporation (the “Exchange Agreement”) shall remain in full force and effect and shall

not have been terminated, amended, or modified in any manner without Lender’s prior written consent;

c. Lender shall have received certified copies of resolutions duly adopted by Borrower and Guarantor authorizing

the execution, delivery and performance of this Note and the transactions contemplated thereby and such resolutions shall remain in full

force and effect and shall not have been terminated, modified, amended or superseded;

d. Borrower shall have delivered to Lender a schedule of all existing indebtedness of Borrower which schedule

shall include the amount of each indebtedness, the maturity date, description of periodic payments, if any, and the name of the lender

or creditor and whether such indebtedness is secured by asses of the Borrower;

e. Guarantor shall have duly executed the Guaranty in the form of Exhibit A annexed hereto; and

f. No Event of Default (as defined below) shall have occurred and be continuing.

5. Advances; Schedule I. Subject to the discretion of Lender to make any advance,

and provided that no Event of Default exists or is continuing, and further provided that the Funding Conditions are satisfied, upon the

written request of the Borrower, the Lender may fund each Advance to the Borrower on a Funding Date, with such Advance in the aggregate

not to exceed the Maximum Principal Amount. Upon delivery of each Advance to the Borrower, the Lender is hereby authorized by Borrower

to enter and record on Grid the amount of such Advance, the principal amount of such Loan and the Funding Date of such Advance without

any further action on the part of Borrower or any endorser or guarantor of this Note. The entry of an Advance on the Grid shall be prima

facie and presumptive evidence of the entered Loan and its conditions. The Lender’s failure to make an entry on the Grid, however,

shall not limit or otherwise affect the obligations of the Lender to make the Advance or of the Borrower or any endorser or guarantor

of this Note with respect to the Loan.

6. Prepayment. The Borrower shall have the right,

at any time and from time to time, to prepay all or any portion of the outstanding principal amount of this Note without notice and without

premium, penalty, make-whole, or other prepayment charge. Any such prepayment shall reduce the outstanding principal balance of this Note

by the amount so prepaid. Each prepayment of principal shall reduce the Closing Credit (as defined below) on a dollar-for-dollar basis;

provided, however, that the Closing Credit shall in no event be less than Five Hundred Thousand Dollars ($500,000). For the avoidance

of doubt, the fixed $500,000 portion of the Closing Credit contemplated by the Section 8 shall be credited to Net Cash (as defined in

the Exchange Agreement) at the Closing (as defined below) irrespective of whether the outstanding principal amount of this Note has been

reduced or prepaid in full prior to the Closing.

7. Interest. Prior to the earlier of (a) the consummation of the transactions

contemplated by the Exchange Agreement (the “Closing”) or (b) the termination of the Exchange Agreement prior

to the Closing (the “Termination”), this Note shall not bear interest. Upon a Termination, interest shall accrue

on the outstanding principal balance of this Note at a rate of twelve percent (12%) per annum commencing on the date of such termination

and continuing until the outstanding principal amount of, and all accrued and unpaid interest due under, this Note is paid in full. Interest

shall be calculated on the basis of a 360-day year and the actual number of days elapsed. Notwithstanding anything to the contrary contained

herein, no default interest, penalty interest, or other increased rate of interest shall apply under any circumstances.

8. Treatment at the Closing. Notwithstanding anything to the contrary contained

herein, upon the Closing, and effective simultaneously therewith, (a) this Note and all obligations, liabilities and indebtedness evidenced

by or arising under this Note shall, automatically and without any further action by Lender, Borrower, Guarantor or any other Person (as

defined in the Exchange Agreement), be irrevocably cancelled, discharged and satisfied in full, and neither the Borrower nor the Guarantor

shall have any further liability with respect thereto; and (b) the Net Cash at Closing (as defined in the Exchange Agreement) shall be

increased by an amount equal to Five Hundred Thousand Dollars ($500,000), plus the aggregate outstanding principal amount of this Note

immediately prior to the Closing (the “Closing Credit”). For illustrative purposes only and without limiting

the foregoing, if only the initial advance under this Note of $2,500,000 has been funded and no prepayment of principal has been made

prior to the Closing, the Closing Credit shall equal $3,000,000; provided, that if this Note has been prepaid in full prior to the Closing,

the Closing Credit shall equal $500,000.

9. Negative Covenant. As long as any portion of this Note remains outstanding,

unless the Lender shall have otherwise given prior written consent, the Borrower shall not, directly or indirectly enter into, create,

incur, assume, guarantee or suffer to exist any indebtedness for borrowed money of any kind, including, but not limited to, a guarantee,

on or with respect to any of its property or assets now owned or hereafter acquired or any interest therein or any income or profits therefrom,

unless the net proceeds of such indebtedness are immediately used to repay the amounts due under this Note.

10. Waiver. The Borrower hereby waives presentment, demand, notice, protest,

and all other demands and notices in connection with the delivery, acceptance, performance and enforcement of this Note, and assent to

extensions of the time of payment or forbearance or other indulgence without notice. No delay or omission of the Lender in exercising

any right or remedy hereunder shall constitute a waiver of any such right or remedy. Acceptance by the Lender of any payment after demand

shall not be deemed a waiver of such demand. A waiver on one occasion shall not operate as a bar to or waiver of any such right or remedy

on any future occasion.

11. Events of Default. If any of the following events of default (each, an "Event

of Default") shall occur and be continuing following any cure period:

a. Failure to Pay Principal or Interest. The Borrower fails to pay the principal hereof or interest

thereon when due on this Note, whether at maturity, upon acceleration or otherwise and such breach continues for a period of five (5)

business days written notice thereof to the Borrower from the Lender.

b. Breach of Covenants. The Borrower breaches the negative covenant contained in this Note such

breach continues for a period of thirty (30) days after written notice thereof to the Borrower from the Lender.

c. Breach of Representations and Warranties. Any representation or warranty of the Borrower made herein or in any agreement, statement

or certificate given pursuant hereto or in connection herewith shall be false or misleading in any material respect when made and the

breach of which has (or with the passage of time will have) a material adverse effect on the rights of the Lender with respect to this

Note.

d. Change of Control Transaction. The Company or Guarantor shall be a party to any Change of Control

Transaction or shall agree to sell or dispose of all or in excess of 50% of its assets in one transaction or a series of related transactions

(whether or not such sale would constitute a Change of Control Transaction), unless the net proceeds of such transaction are immediately

used to pay all amounts due under the Note.

i. “Change of Control Transaction” means the occurrence after the date hereof

of any of (a) an acquisition after the date hereof by an individual or legal entity or “group” (as described in Rule 13d-5(b)(1)

promulgated under the Exchange Act) of effective control (whether through legal or beneficial ownership of capital stock of the Borrower,

by contract or otherwise) of in excess of 50% of the voting securities of the Borrower, (b) the Borrower merges into or consolidates with

any other Person, or any Person merges into or consolidates with the Company and, after giving effect to such transaction, the shareholders

of the Borrower immediately prior to such transaction own less than 50% of the aggregate voting power of the Borrower or the successor

entity of such transaction, (c) the Borrower sells or transfers all or substantially all of its assets to another Person, (d) a replacement

at one time or within a one year period of more than one-half of the members of the board of directors of the Borrower as of the date

of this Note (the “Board”), or (d) the execution by the Borrower of an agreement to which the Borrower is a

party or by which it is bound, providing for any of the events set forth in clauses (a) through (d) above.

e. Bankruptcy. Bankruptcy, insolvency, reorganization or liquidation proceedings or other proceedings,

voluntary or involuntary, for relief under any bankruptcy law or any law for the relief of debtors shall be instituted by or against the

Borrower or the Guarantor which has not been dismissed 60 days after its filing.

f. Invalidity of Guarantee. The Guarantee ceases to be in full

force and effect or is repudiated by the Guarantor.

g. Remedies. UPON THE OCCURRENCE AND DURING THE CONTINUATION OF ANY EVENT OF DEFAULT SPECIFIED

IN SECTION 13, THE NOTE SHALL BECOME IMMEDIATELY DUE AND PAYABLE AND THE BORROWER SHALL PAY TO THE LENDER, IN FULL SATISFACTION OF ITS

OBLIGATIONS HEREUNDER, AN AMOUNT EQUAL TO THE PRINCIPAL AMOUNT THEN OUTSTANDING AND ANY ACCRUED INTEREST.

12. Remedies. UPON THE OCCURRENCE AND DURING THE CONTINUATION OF ANY EVENT OF

DEFAULT SPECIFIED IN SECTION 11, THIS NOTE SHALL BECOME IMMEDIATELY DUE AND PAYABLE.

13. Security Interest. The obligations under this Note are unsecured.

14. Representations and Warranties of Lender.

a. Organization, Good Standing and Qualification. Lender is a corporation

duly organized, validly existing and in good standing under the laws of the State of Delaware. Lender has the requisite corporate power

and authority to own and operate its properties and assets, to carry on its business as presently conducted, to execute and deliver this

Note and to perform its obligations hereunder. Lender is presently qualified to do business as a foreign entity in each jurisdiction where

the failure to be so qualified could reasonably be expected to have a material adverse effect on the Lender’s financial condition

or business as now conducted.

b. Authorization. All corporate action on the part of Lender and its

directors, officers and stockholders necessary for the performance of all of Lender’s obligations thereunder, has been taken prior

to the date hereof. This Note, as executed and delivered by Lender, constitutes valid and binding obligations of Lender, enforceable in

accordance with its terms, except as enforceability may be limited by applicable bankruptcy, insolvency, reorganization, moratorium or

similar laws affecting the enforcement of creditors' rights generally

15. Representations and Warranties of Borrower.

a. Organization, Good Standing and Qualification. The Borrower is a

company duly organized, validly existing and in good standing under the laws of Delaware. The Borrower has the requisite limited liability

company power and authority to own and operate its properties and assets, to carry on its business as presently conducted, to execute

and deliver this Note and to perform its obligations hereunder. The Borrower is presently qualified to do business in each jurisdiction

where the failure to be so qualified could reasonably be expected to have a material adverse effect on the Borrower’s financial

condition or business as now conducted.

b. Authorization. All limited liability company action on the part

of the Borrower and its directors, officers and stockholders necessary for the authorization, sale, issuance and delivery of this Note,

and the performance of all of the Borrower’s obligations thereunder, has been taken prior to the date hereof. This Note, as executed

and delivered by the Borrower, constitutes valid and binding obligations of the Borrower, enforceable in accordance with its terms, except

as enforceability may be limited by applicable bankruptcy, insolvency, reorganization, moratorium or similar laws affecting the enforcement

of creditors' rights generally.

c. No Violations. The execution and delivery of this Note and the consummation

and performance by the Borrower of its obligations contemplated hereby do not and will not (a) violate any provision of Borrower organizational

or constitutional documentation; (b) violate any law or governmental order applicable to the Borrower or by which any of its properties

or assets may be bound; or (c) constitute a default under any contract, instrument or agreement binding on the Borrower or its assets

or constitute a default or termination event (however described) under any such contract, instrument or agreement.

16. Miscellaneous.

a. Notices. All notices, demands, requests, consents, approvals, and other communications required

or permitted hereunder shall be in writing and, unless otherwise specified herein, shall be (i) personally served, (ii) deposited in the

mail, registered or certified, return receipt requested, postage prepaid, (iii) delivered by reputable air courier service with charges

prepaid, or (iv) transmitted by hand delivery, telegram, or facsimile, addressed as set forth below or to such other address as such party

shall have specified most recently by written notice. Any notice or other communication required or permitted to be given hereunder shall

be deemed effective (a) upon hand delivery or delivery by facsimile, with accurate confirmation generated by the transmitting facsimile

machine, at the address or number designated below (if delivered on a business day during normal business hours where such notice is to

be received), or the first business day following such delivery (if delivered other than on a business day during normal business hours

where such notice is to be received), (b) on the second business day following the date of mailing by express courier service, fully prepaid,

addressed to such address, or upon actual receipt of such mailing, whichever shall first occur or (c) five (5) days after deposited in

the mail. The addresses for such communications shall be as set forth above or such other address as a Party may designate by providing

notice of such change to the other Party.

b. Amendments. This Note and any provision hereof may only be amended by an instrument in writing

signed by the Borrower and the Lender. The term “Note” and all reference thereto, as used throughout this instrument, shall

mean this instrument as originally executed, or if later amended or supplemented, then as so amended or supplemented.

c. Assignability. Neither this

Note nor any rights hereunder are transferable without the prior written consent of the Borrower, which consent the Borrower shall not

unreasonably withhold. Subject to the foregoing, the provisions of this Note shall inure to the benefit of, and be binding upon, the successors,

assigns, heirs, executors, and administrators of the Borrower and the Lender.

d. Cost of Collection. If default is made in the payment of this Note, the Borrower shall pay the

Lender hereof costs of collection, including reasonable attorneys' fees.

e. Governing Law; Arbitration. This Note and all actions arising out

of or in connection herewith or therewith shall be governed by and construed in accordance with the laws of the State of Delaware, without

regard to the conflicts of law provisions of the State of Delaware or of any other state, country or jurisdiction. Any dispute, claim,

or controversy arising out of or relating to this Note, the other Loan Documents, or the breach, termination, enforcement, interpretation,

or validity thereof, shall be resolved exclusively by final and binding arbitration administered by JAMS in accordance with its Comprehensive

Arbitration Rules and Procedures then in effect. The arbitration shall be conducted by a single arbitrator (mutually agreed upon by the

Borrower and the Lender) in Wilmington, Delaware. Judgment upon the award rendered by the arbitrator may be entered in any court having

jurisdiction thereof. Notwithstanding the foregoing, either party may seek temporary, preliminary, or permanent injunctive relief or other

equitable remedies from the arbitrator, and any court having jurisdiction may grant provisional remedies in aid of arbitration and enforce

any arbitral award. EACH PARTY KNOWINGLY, VOLUNTARILY, AND IRREVOCABLY WAIVES ANY RIGHT TO A TRIAL BY JURY OR TO LITIGATE ANY DISPUTE

IN COURT, EXCEPT AS NECESSARY TO ENFORCE THIS ARBITRATION PROVISION OR AN ARBITRATION AWARD.

[signature

page follows]

IN WITNESS

WHEREOF, Borrower and Guarantor have caused this Note to be executed and delivered as of the day and year and at the place first above

written.

BORROWER:

Realbotix, LLC

By:

Name:

Andrew Kiguel

Title:

Chief Executive Officer

GUARANTOR:

Realbotix Corp.

By:

Name:

Andrew Kiguel

Title:

Chief Executive Officer

LENDER:

Onconetix, Inc.

By:

Name:

David White

Title:

Chief Executive Officer

SCHEDULE I TO NOTE

Borrower: Realbotix, LLC

Lender: Onconetix, Inc.

Guarantor: Realbotix Corp.

Funding Date

Advance Amount

Principal Amount

9/11/26

$ 2,500,000.00

Total:

$ 2,500,000.00

Exhibit A

Form of Guaranty

EX-10.2 — FORM OF GUARANTY OF PAYMENT, DATED SEPTEMBER 11, 2026, BY REALBOTIX CORP. IN FAVOR OF ONCONETIX, INC

EX-10.2

Filename: ea030515701ex10-2.htm · Sequence: 3

Exhibit 10.2

GUARANTY OF PAYMENT

THIS GUARANTY OF PAYMENT

(as the same may be hereafter amended, modified, restated, renewed, replaced, supplemented or extended, this “Guaranty”)

is made as of September 11, 2026, by Realbotix Corp., an Ontario corporation (the “Guarantor”), in favor of

Onconetix, Inc., a Delaware corporation (together with its permitted successors and assigns, “Lender”).

R E C I T A L S:

WHEREAS, contemporaneously

herewith, Lender is making available to Realbotix, LLC, a Delaware limited liability company (“Borrower”), loans

in an aggregate principal amount of up to $5,000,000 (the “Loans”) pursuant to that certain Grid Promissory

Note, dated as of the date hereof, made by Borrower, as maker, in favor of Lender, as payee (together with all extensions, renewals, modifications,

substitutions and amendments thereof made in accordance with its terms, the “Note”);

WHEREAS, Borrower is

an indirect subsidiary of Guarantor;

WHEREAS, Lender requires

as a condition of entering into the Note that Guarantor shall execute and deliver this Guaranty for the benefit of Lender and Guarantor,

as a holder of a direct or indirect interest in Borrower or an Affiliate of Borrower will derive substantial direct or indirect economic

benefit from making of the Loan; and

WHEREAS, all capitalized

terms used in this Guaranty but not defined herein have the respective meanings given to such terms in the Note.

NOW, THEREFORE, in consideration

of the premises and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, and in order

to induce Lender to make the Loans to Borrower, Guarantor hereby represents, warrants, covenants and agrees with Lender as follows:

1. Authorization

and Enforceability of Loan Documents. The Note, this Guaranty and each other agreement, instrument and document, if any, executed

and delivered by Borrower or Guarantor in connection with the Loans (as the same may be amended, modified, restated, renewed, replaced,

supplemented or extended in accordance with their terms, collectively, the “Loan Documents”) have been duly

authorized and executed by Borrower or Guarantor, as applicable, and constitute legal, valid and binding obligations of Borrower or Guarantor,

as applicable, enforceable against such party in accordance with their respective terms, subject to bankruptcy, insolvency, reorganization,

moratorium and other legal or equitable principles now or hereafter in effect generally affecting creditors’ rights and remedies.

2. Obligations

Guaranteed. Guarantor absolutely, unconditionally and irrevocably guarantees to Lender the due and punctual payment and performance

of the following obligations, in each case when due under the Note and subject to clause (d) below (collectively, the “Guaranteed

Obligations”):

(a) the

outstanding principal amount of all Advances made under the Note and all interest that accrues thereon in accordance with Section 7 of

the Note, in each case when due at stated maturity, by acceleration or otherwise;

(b) all

other payment and performance obligations of Borrower under the Note, including all costs of collection that Borrower is required to pay

under Section 16(d) of the Note;

reasonable out-of-pocket costs and expenses incurred by Lender in enforcing this Guaranty, including reasonable attorneys’ fees,

in each case to the extent permitted by applicable law (collectively, the “Expenses”); and

(d) notwithstanding

anything to the contrary in this Guaranty, upon the Closing and effective simultaneously therewith, the Guaranteed Obligations and this

Guaranty shall automatically and irrevocably be cancelled, discharged and satisfied in full, and Guarantor shall have no further liability

hereunder, all in accordance with Section 8 of the Note.

3. Conditional

Guaranty. Default Notice and Cure. This Guaranty is a guaranty of payment and performance and not of collection.

Notwithstanding anything to the contrary herein or in any other Loan Document, Lender shall not exercise any rights or remedies against

Guarantor, nor shall Guarantor be in default hereunder, unless and until:

(a) an Event of Default

under the Note has occurred and is continuing beyond any applicable notice and cure period provided to Borrower therein;

(b) Lender has delivered

written notice to Guarantor specifying such Event of Default; and

within ten (10) Business Days following receipt of such written notice.

Subject to the foregoing

notice and cure rights, the terms of the Note (including Section 8 thereof), and the receipt of any required regulatory approvals (including

the acceptance of the TSX Venture Exchange, if applicable), Lender may proceed directly against Guarantor to collect amounts then due

and payable hereunder. Guarantor waives and releases any claim (within the meaning of 11 U.S.C. § 101) against Borrower arising from

a payment by Guarantor under this Guaranty, and agrees not to exercise any subrogation, contribution, or reimbursement right against Borrower,

in each case only until the Guaranteed Obligations have been indefeasibly paid in full or otherwise cancelled, discharged, and satisfied

in accordance with Section 8 of the Note.

4. Liability

Unimpaired. Subject in all cases to Section 8 of the Note, Guarantor’s liability shall not be limited or impaired by: (i) any

extension, renewal, forbearance, amendment or modification of the Note or any other Loan Document made in accordance with its terms; (ii)

any settlement or compromise with, or release of, Borrower or any other Person liable for the Guaranteed Obligations; (iii) any failure

by Lender to exercise, or delay by Lender in exercising, any right or remedy; (iv) the invalidity, irregularity or unenforceability, in

whole or in part, of the Note, any other Loan Document or any obligation of Borrower thereunder; or (v) any other action or circumstance

that might otherwise constitute a legal or equitable discharge or defense of a guarantor, other than the indefeasible payment and performance

in full of the Guaranteed Obligations or the cancellation, discharge and satisfaction thereof at the Closing in accordance with Section

8 of the Note. Nothing in this Section shall expand Guarantor’s liability beyond the obligations of Borrower under the Note.

5. Defined

Terms. Capitalized terms used but not defined in this Guaranty have the meanings given to them in the Note. As used herein, the following

terms have the meanings set forth below:

(a) “Closing”

has the meaning given to such term in the Note.

(b) “Affiliate”

means, with respect to any Person, any other Person that directly or indirectly controls, is controlled by, or is under common control

with such Person; and “control” means the direct or indirect power to direct or cause the direction of the management and

policies of a Person, whether through ownership, contract or otherwise.

Costs” means the Expenses and any other reasonable out-of-pocket costs and expenses incurred by Lender in enforcing this

Guaranty, including reasonable attorneys’ fees, in each case to the extent permitted by applicable law.

(d) “Exchange

Agreement” means the Share Exchange Agreement dated as of February 11, 2026 among Lender, Borrower, Guarantor and Simulacra

Corporation, as the same may be amended, modified or supplemented from time to time.

(e) “Person”

means any individual, corporation, partnership, limited liability company, joint venture, estate, trust, unincorporated association, governmental

authority or other entity.

6. Preservation

of Loan Documents. Guarantor will not cause or permit Borrower to take or fail to take any action for the purpose of impairing the

enforceability of the Loan Documents or creating a defense to Guarantor’s obligations hereunder, subject to Borrower’s and

Guarantor’s express rights under the Note and the Exchange Agreement, including Section 8 of the Note.

7. Payments;

Certain Waivers. Guarantor waives presentment, demand (except as expressly required by Section 3 hereof or the Note), protest, notice

of acceptance of this Guaranty, and notice of default (except as expressly required by Section 3 hereof or the Note). Guarantor also waives

any right to require a marshalling of Borrower’s assets. Guarantor expressly retains all rights of subrogation, contribution, indemnification,

set-off, and reimbursement that Guarantor may have against Borrower or any other Person; provided, however, that Guarantor shall defer

the enforcement or exercise of any such rights, and such rights shall be subordinate to Lender’s right to payment under the Note,

solely during such time as any Guaranteed Obligations remain outstanding and unpaid. Immediately upon the indefeasible payment of the

Guaranteed Obligations or the automatic cancellation, discharge, and satisfaction of the Guaranteed Obligations at the Closing pursuant

to Section 8 of the Note, all such subrogation, contribution, indemnification, set-off, and reimbursement rights of Guarantor shall automatically

be fully unencumbered, reinstated, and enforceable without further action by any party.

8. Reinstatement.

Except for the cancellation, discharge and satisfaction of this Guaranty and the Guaranteed Obligations at the Closing pursuant to Section

8 of the Note, this Guaranty shall continue to be effective or shall be reinstated automatically, as applicable, if any payment of a Guaranteed

Obligation is rescinded or otherwise must be restored or returned by Lender as a preference, fraudulent transfer or otherwise in connection

with an insolvency, bankruptcy, dissolution, liquidation or reorganization of Borrower. In that event, all reasonable Enforcement Costs

incurred by Lender in defending or enforcing such continuance or reinstatement shall be included in the Expenses guaranteed under Section

9. Litigation;

Compliance with Judgments. Guarantor represents and warrants that there are no actions, suits or proceedings pending or, to Guarantor’s

knowledge, threatened against Guarantor, at law, in equity or before any governmental authority, that would reasonably be expected to

have a material adverse effect on Guarantor’s ability to perform its obligations hereunder. To Guarantor’s knowledge, Guarantor

is not in default with respect to any order, writ, injunction, decree or demand of any court or governmental authority that would reasonably

be expected to have such an effect.

10. Authorization

and Enforceability; No Conflicts. Guarantor represents and warrants that it has full power and authority to enter into and perform

its obligations under this Guaranty; the execution, delivery and performance of this Guaranty have been authorized by all necessary corporate

action; and this Guaranty constitutes a legal, valid and binding obligation of Guarantor, enforceable against Guarantor in accordance

with its terms, subject to bankruptcy, insolvency, reorganization, moratorium and other legal or equitable principles now or hereafter

in effect generally affecting creditors’ rights and remedies. Guarantor further represents and warrants that the execution, delivery

and performance of this Guaranty do not and will not violate Guarantor’s organizational documents, applicable law or any material

agreement binding on Guarantor or its assets.

11. Compliance

with Laws. Guarantor represents and warrants that the execution, delivery and performance of this Guaranty do not and will not violate

any applicable federal, state, provincial or local law, rule, regulation, ordinance, order, writ, judgment, injunction, decree, determination

or award, or require any filing, registration, consent or approval thereunder, except for any filing, registration, consent or approval

that has been made or obtained and remains in full force and effect.

12. Accuracy

of Information; Full Disclosure. Guarantor represents and warrants that no document, financial statement, report, notice, schedule,

certificate, statement or other writing furnished by or on behalf of Guarantor to Lender in connection with this Guaranty or the Loans

contains any untrue statement of a material fact or omits to state a material fact necessary to make the statements therein, in light

of the circumstances in which they were made, not misleading, in each case as of the date furnished.

13. Non-Waiver;

Remedies Cumulative. No failure or delay by Lender in exercising any right, power or privilege under any Loan Document or this Guaranty

shall operate as a waiver thereof or constitute acquiescence in any default by Borrower or Guarantor. A waiver on one occasion shall not

bar the exercise of any right or remedy on a future occasion. Subject to the Note, the rights and remedies provided in the Loan Documents

and this Guaranty are cumulative and are not exclusive of any rights or remedies provided by law.

14. Transfers

of Interests in Loans. Lender may sell, assign or transfer the Note, this Guaranty or any interest therein only as permitted by Section

16(c) of the Note. Guarantor consents to Lender’s disclosure of the Loan Documents and information relating to Borrower or Guarantor

to any prospective or actual transferee in connection with a transfer permitted by the Note, subject to applicable law and customary confidentiality

obligations.

15. Subordination

of Guarantor Loans. Any indebtedness now or hereafter owed by Borrower to Guarantor or any Affiliate of Guarantor is and shall remain

subordinate to the Guaranteed Obligations. Guarantor shall not accept any payment of principal or interest on such indebtedness while

prohibited by Sections 1 or 9 of the Note. This Section shall cease to apply when the Guaranteed Obligations have been indefeasibly paid

and performed in full or otherwise discharged in accordance with Section 8 of the Note.

16. Severability.

If any provision of this Guaranty, or its application to any Person or circumstance, is prohibited or unenforceable in any jurisdiction,

such provision shall be ineffective in that jurisdiction only to the extent of such prohibition or unenforceability, without invalidating

the remaining provisions of this Guaranty or the application of such provision to any other Person, circumstance or jurisdiction.

17. Entire

Agreement; Amendments. This Guaranty contains the entire agreement of Guarantor and Lender with respect to its subject matter and

supersedes all prior oral or written agreements or statements relating to such subject matter. No provision of this Guaranty may be waived,

amended or terminated except by a written instrument signed by Guarantor and Lender; provided that this sentence shall not limit the automatic

cancellation, discharge and satisfaction provided by Section 8 of the Note.

18. Successors

and Assigns. This Guaranty shall bind Guarantor and its successors and permitted assigns and shall inure to the benefit of Lender

and its successors and permitted assigns. Neither this Guaranty nor any right hereunder may be assigned or transferred except in connection

with a transfer of the Note permitted by Section 16(c) of the Note.

19. Arbitration;

Waiver of Trial by Jury. This Note and all actions arising out of or in connection herewith or therewith shall be governed by and

construed in accordance with the laws of the State of Delaware, without regard to the conflicts of law provisions of the State of Delaware

or of any other state, country or jurisdiction. Any dispute, claim, or controversy arising out of or relating to this Note, the other

Loan Documents, or the breach, termination, enforcement, interpretation, or validity thereof, shall be resolved exclusively by final and

binding arbitration administered by JAMS in accordance with its Comprehensive Arbitration Rules and Procedures then in effect. The arbitration

shall be conducted by a single arbitrator (mutually agreed upon by the Borrower and the Lender) in Wilmington, Delaware. Judgment upon

the award rendered by the arbitrator may be entered in any court having jurisdiction thereof. Notwithstanding the foregoing, either party

may seek temporary, preliminary, or permanent injunctive relief or other equitable remedies from the arbitrator, and any court having

jurisdiction may grant provisional remedies in aid of arbitration and enforce any arbitral award. EACH PARTY KNOWINGLY, VOLUNTARILY, AND

IRREVOCABLY WAIVES ANY RIGHT TO A TRIAL BY JURY OR TO LITIGATE ANY DISPUTE IN COURT, EXCEPT AS NECESSARY TO ENFORCE THIS ARBITRATION PROVISION

OR AN ARBITRATION AWARD.

20. Provisional

Remedies; Enforcement of Awards. Notwithstanding Section 19, either Guarantor or Lender may seek temporary, preliminary or permanent

injunctive relief or other equitable remedies from the arbitrator, and any court having jurisdiction may grant provisional remedies in

aid of arbitration and enforce any arbitral award.

21. Governing

Law. This Guaranty and all actions arising out of or in connection with it shall be governed by and construed in accordance with the

laws of the State of Delaware, without regard to the conflict-of-laws provisions of the State of Delaware or any other jurisdiction.

22. Section

Headings. The section headings and captions in this Guaranty are for convenience only and do not affect its interpretation or construction.

23. Liability

Unaffected by Release. Except for the cancellation and discharge provided by Section 8 of the Note or an express written release of

Guarantor by Lender, any release of Borrower or any other Person liable for a Guaranteed Obligation shall not affect Guarantor’s

liability under this Guaranty.

24. Notices.

All notices and other communications under this Guaranty shall be given in the manner provided in Section 16(a) of the Note and, in the

case of Guarantor, shall be sent to Guarantor at the address specified for Guarantor in the Note or to such other address as Guarantor

may designate by notice given in accordance with this Section.

25. Principles

of Construction. All references to sections, schedules and exhibits are to sections, schedules and exhibits of or to this Guaranty

unless otherwise specified. The words “hereof,” “herein” and “hereunder” refer to this Guaranty as

a whole. The recitals are part of this Guaranty, and all attached exhibits and schedules, if any, are incorporated by reference. Defined

terms apply equally to singular and plural forms; “including” means “including without limitation”; and references

to any agreement include amendments, modifications and supplements made in accordance with its terms.

26. Counterparts;

Electronic Signatures. This Guaranty may be executed in counterparts, each of which is deemed an original and all of which together

constitute one instrument. Signatures delivered by electronic transmission, including by PDF or other electronic means, shall be effective

as originals.

27. TSXV

Conditionality. Notwithstanding anything herein to the contrary, the enforceability of this Guaranty is subject to the receipt of

all required regulatory approvals, including the acceptance of the TSX Venture Exchange.

[REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

IN WITNESS WHEREOF, Guarantor

has caused this Guaranty to be duly executed and delivered by its duly authorized officer as of the date first above written.

GUARANTOR:

REALBOTIX CORP.

By:

Name:

Title:

[SIGNATURE PAGE TO GUARANTY OF PAYMENT]

EX-99.1 — PRESS RELEASE, DATED SEPTEMBER 14, 2026

EX-99.1

Filename: ea030515701ex99-1.htm · Sequence: 4

Exhibit 99.1

Filed by Onconetix, Inc.

Pursuant to Rule 425 under the Securities Act

of 1933

and deemed filed pursuant to Rule 14a-6(b)

under the Securities Exchange Act of 1934

Subject Company: Onconetix, Inc.

Commission File No.: 001-41294

Date: September 14,2026

Onconetix Provides Strategic Bridge Financing

to Realbotix LLC in Support of Pending Acquisition

Initial Advance of $2.5 Million to Realbotix

LLC to Support Growth and Working Capital; Non-Interest Bearing Facility Is Automatically Cancelled and Discharged in Full Upon Closing

of Pending Acquisition

CINCINNATI, Ohio – September 14, 2026,

2026 – Onconetix, Inc. (Nasdaq: ONCO) ("Onconetix" or the "Company") today announced that it has provided

a strategic bridge financing facility of up to $5,000,000 to Realbotix LLC ("Realbotix"), the target of its previously announced

pending acquisition, to support Realbotix's growth and working capital needs while the parties advance toward closing of the acquisition.

The financing was provided in connection with the Share Exchange Agreement between the two companies, announced on February 12, 2026.

The facility provides for an aggregate principal

amount of up to $5,000,000, with an initial advance of $2,500,000.

The facility is non-interest bearing prior to

the closing of the Share Exchange Agreement. Upon closing of the acquisition, the facility and all obligations thereunder will be automatically

cancelled and discharged in full. In addition, the cash required at closing of the acquisitions will be reduced by the total principal

advanced under the facility plus an additional $500,000. If the Share Exchange Agreement is terminated, interest accrues at 12% per annum

from the date of termination. A description of the Note is included in Onconetix’s Current Report on Form 8-K filed with the SEC

on September 14, 2026. The full text of the Note is filed as an exhibit to that report and is available at www.sec.gov.

As previously announced on February 12, 2026,

Onconetix entered into the Share Exchange Agreement to acquire 100% of the issued and outstanding equity interests of Realbotix LLC in

an all-stock transaction. The combined company is expected to trade on Nasdaq following closing, which is subject to Onconetix shareholder

approval, required regulatory approvals, and other closing conditions.

This communication is being provided for informational

purposes only. Investors are cautioned not to place undue reliance on forward-looking or projected information.

About Onconetix, Inc.

Onconetix, Inc. (Nasdaq: ONCO) is a commercial-stage

biotechnology company focused on the research, development, and commercialization of innovative oncology solutions. Onconetix owns Proclarix®,

an in vitro diagnostic test for prostate cancer originally developed by Proteomedix and approved for sale in the European Union under

the IVDR, which it anticipates will be marketed in the U.S. as a lab developed test through its license agreement with Labcorp. For more

information, visit www.onconetix.com.

About Realbotix LLC

Realbotix LLC is a wholly-owned subsidiary of

Realbotix Corp. (TSX-V: XBOT; Frankfurt: 76M0.F; OTC: XBOTF) and the target of Onconetix’s pending acquisition. Realbotix LLC develops

AI-powered humanoid robots designed for human interaction across enterprise and consumer environments. Manufactured in the United States,

Realbotix’s patented AI and robotics technologies enable lifelike expressions, motion, vision, and social engagement. For more information,

visit www.realbotix.ai.

Additional Information and Where to Find It

In connection with the proposed transaction between

Realbotix and Onconetix, Onconetix intends to file with the SEC a Registration Statement on Form S-4 (the “Registration Statement”)

to register the common stock to be issued by Onconetix in connection with the proposed transaction. The Registration Statement will include

a proxy statement of Onconetix and a prospectus of Onconetix (the “Proxy Statement/Prospectus”), and each of Realbotix and

Onconetix may file with the SEC other relevant documents concerning the proposed transaction. After the Registration Statement is declared

effective, the definitive Proxy Statement/Prospectus will be sent to the stockholders of Onconetix to seek their approval of the proposed

transaction. This is not a substitute for the Registration Statement, the Proxy Statement/Prospectus or any other relevant documents that

Realbotix or Onconetix has filed or will file with the SEC. BEFORE MAKING ANY VOTING OR INVESTMENT DECISION, INVESTORS AND STOCKHOLDERS

OF ONCONETIX ARE URGED TO CAREFULLY AND ENTIRELY READ THE REGISTRATION STATEMENT AND PROXY STATEMENT/PROSPECTUS REGARDING THE PROPOSED

TRANSACTION AND ANY OTHER RELEVANT DOCUMENTS, AS WELL AS ANY AMENDMENTS OR SUPPLEMENTS TO THOSE DOCUMENTS, IF AND WHEN THEY BECOME AVAILABLE,

BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT REALBOTIX, ONCONETIX, THE PROPOSED TRANSACTION, AND RELATED MATTERS.

A copy of the Registration Statement, Proxy Statement/Prospectus,

as well as other relevant documents filed by Realbotix and Onconetix with the SEC, may be obtained free of charge, when they become available,

at the SEC’s website at www.sec.gov. The information on Realbotix or Onconetix’s respective websites is not, and shall not

be deemed to be, a part of this communication or incorporated into other filings either company makes with the SEC.

Participants in the Solicitation

Realbotix, Onconetix and certain of their respective

directors, executive officers, and employees may be deemed to be participants in the solicitation of proxies in connection with the proposed

transaction. Information about the directors and executive officers of Onconetix, their ownership of Onconetix common stock, and Onconetix’s

transactions with related persons is set forth in the 10-K, as filed with the SEC on March 13, 2026, and other documents that may be filed

from time to time with the SEC. Additional information about the directors and executive officers of Realbotix and Onconetix and other

persons who may be deemed to be participants in the solicitation of stockholders of Onconetix in connection with the proposed transaction

and a description of their direct and indirect interests will be included in the Proxy Statement/Prospectus related to the proposed transaction

or other relevant materials, which will be filed with the SEC. These documents may be obtained free of charge, when they become available,

at the SEC’s website at www.sec.gov and from Onconetix using the sources indicated above.

No Offer or Solicitation

This communication is for informational purposes

only and is not intended to and does not constitute an offer to sell or the solicitation of an offer to buy or sell any securities or

the solicitation of any proxy, vote or approval, nor shall there be any sale of securities in any jurisdiction in which such offer, solicitation

or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. No offer of securities

shall be made except by means of a prospectus meeting the requirements of Section 10 of the Securities Act, or in a transaction exempt

from the registration requirements of the Securities Act.

Forward-Looking Statements

Certain statements in this press release are forward-looking

within the meaning of the Private Securities Litigation Reform Act of 1995. These statements may be identified by the use of forward-looking

words such as “anticipate,” “believe,” “forecast,” “estimate,” “expect,” and

“intend,” among others. These forward-looking statements (including, without limitation, the anticipated benefits and opportunities

that may be generated by the proposed transaction described herein) are based on Onconetix’s current expectations and actual results

could differ materially. There are a number of factors that could cause actual events to differ materially from those indicated by such

forward-looking statements. These factors include, but are not limited to, the occurrence of any event, change, or other circumstances

that could give rise to the right of one or both of the parties to terminate the share exchange agreement; the possibility that the proposed

transaction does not close when expected or at all because the conditions to closing are not satisfied on a timely basis or at all, including

the failure to timely obtain stockholder approval for the proposed transaction from Onconetix’s stockholders, if at all; risks related

to Onconetix’s continued listing on Nasdaq until closing of the proposed transaction; the outcome of any legal proceedings that

may be instituted against Realbotix, Onconetix, or the combined company; the possibility that the anticipated benefits of the proposed

transaction are not realized when expected or at all; the possibility that the vision, goals, and trajectory of the combined company are

not timely achieved or realized or achieved or realized at all; the possibility that the proposed transaction may be more expensive or

take longer to complete than anticipated, including as a result of unexpected factors or events; the diversion of management’s attention

from ongoing business operations and opportunities; changes in Onconetix’s stock price before closing; and other factors that may

affect future results of Realbotix, Onconetix, or the combined company. Onconetix does not undertake an obligation to update or revise

any forward-looking statement. Investors should read the risk factors set forth in Onconetix’s Annual Report on Form 10-K filed

with the SEC on March 13, 2026 (the “10-K”) and periodic reports filed with the SEC on or after the date thereof. All of Onconetix’s

forward-looking statements are expressly qualified by all such risk factors and other cautionary statements. The information set forth

herein speaks only as of the date thereof.

Investor and Media Contact:

Onconetix, Inc.

201 E. Fifth Street, Suite 1900

Cincinnati, OH 45202

Phone: (513) 620-4101

Email: investors@onconetix.com

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The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Exchange Act

-Number 240

-Section 12

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The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

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-Section 12

-Subsection b-2

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Local phone number for entity.

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No definition available.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 13e

-Subsection 4c

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Title of a 12(b) registered security.

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Name of the Exchange on which a security is registered.

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-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection d1-1

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 14a

-Subsection 12

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Trading symbol of an instrument as listed on an exchange.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Securities Act

-Number 230

-Section 425

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