[6-K] Radiopharm Theranostics Ltd Current Report (Foreign Issuer)

Rhea-AI Filing Summary

Radiopharm Theranostics Limited furnished a Form 6-K to provide U.S. investors with an announcement it released on the Australian Securities Exchange. The attached notice, titled “RAD Approval for Phase 1 Therapeutic Trial of RAD 402,” relates to regulatory approval for a Phase 1 therapeutic trial involving RAD 402. The announcement is included as Exhibit 99.1 and the Form 6-K specifies that it is being furnished rather than filed for U.S. securities law purposes.

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 November 2025

Commission File Number: 001-41621

RADIOPHARM THERANOSTICS LIMITED

(Name of Registrant)

Level 3, 62 Lygon Street, Carlton South, Victoria, 3053, Australia

(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 ☐

Indicate by check mark whether by furnishing the information contained in this Form, the registrant is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes ☐       No ☒

If “Yes” is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b): 82-

RADIOPHARM THERANOSTICS LIMITED

EXPLANATORY NOTE

Radiopharm Theranostics Limited (the “Company”) published one announcement (the “Public Notice”) to the Australian Securities Exchange on November 18, 2025 titled:

“RAD Approval for Phase 1 Therapeutic Trial of RAD 402”

A copy of the Public Notice is attached as an exhibit to this report on Form 6-K.

This report on Form 6-K (including the exhibit hereto) shall not be deemed to be “filed” for purposes of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) and shall not be incorporated by reference into any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

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EXHIBITS

Exhibit Number		Description
99.1		RAD Approval for Phase 1 Therapeutic Trial of RAD 402

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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.

	RADIOPHARM THERANOSTICS LIMITED
Date: November 18, 2025	By:	/s/ Phillip Hains
		Phillip Hains
		Company Secretary

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FAQ

What did RADX disclose in this Form 6-K filing?

Radiopharm Theranostics Limited furnished a Form 6-K to make available an Australian Securities Exchange announcement titled “RAD Approval for Phase 1 Therapeutic Trial of RAD 402.” The announcement is attached as Exhibit 99.1.

What is the main subject of Radiopharm Theranostics (RADX) latest Form 6-K?

The Form 6-K centers on an Australian Securities Exchange announcement concerning approval for a Phase 1 therapeutic trial of RAD 402, which is provided to U.S. investors as Exhibit 99.1.

How is the RAD 402 Phase 1 trial information provided to U.S. investors?

The information is provided through a Form 6-K, which includes as Exhibit 99.1 the full Australian Securities Exchange announcement about approval for a Phase 1 therapeutic trial of RAD 402.

Is the RADX Form 6-K considered filed or furnished under U.S. securities laws?

The Form 6-K states that it, including the exhibit, shall not be deemed to be “filed” for purposes of the U.S. Securities Exchange Act of 1934 and will only be incorporated by reference into other filings if specifically referenced.

What exhibit is attached to Radiopharm Theranostics (RADX) November 2025 Form 6-K?

The Form 6-K includes Exhibit 99.1, which is the Australian Securities Exchange announcement titled “RAD Approval for Phase 1 Therapeutic Trial of RAD 402.”