Onconetix advances $500,000 to Realbotix under grid note

Onconetix, Inc. (ONCO) disclosed on October 22, 2026, that it made an additional $500,000 advance to Realbotix, LLC. The payment was made pursuant to a Grid Promissory Note dated September 11, 2026. This development extends the financial support the company has provided to Realbotix under the existing facility.

The note allows Onconetix to make available loans to Realbotix with an aggregate principal amount of up to $5.0 million. Prior to this latest payment, Onconetix had already advanced $2.5 million to Realbotix on September 11, 2026. The company previously detailed these terms in a Current Report on Form 8-K filed with the Securities and Exchange Commission on September 14, 2026.

Following the recent $500,000 advance, the aggregate principal amount outstanding under the note now stands at $3.0 million. The terms of the note remain unchanged from those previously disclosed. The company incorporated the description of the note from the prior filing by reference in its latest report.

Onconetix filed this update as a Current Report on Form 8-K with the SEC. The filing was dated October 23, 2026, and signed by David A. White, the company's Chief Executive Officer. The report falls under Item 8.01 for Other Events and includes the standard exhibits for interactive data.