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 April 2026
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 (the “Company”) published one announcement (the “Public Notice”) to the Australian Securities Exchange on April 7, 2026 titled:
RADIOPHARM THERANOSTICS LIMITED
EXPLANATORY NOTE
“RAD and Siemens Sign Clinical Supply Agreement for RAD101 ”
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.
EXHIBITS
| Exhibit Number |
Description | |
| 99.1 | RAD and Siemens Sign Clinical Supply Agreement for RAD101 |
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: April 7, 2026 | By: | /s/ Phillip Hains |
| Phillip Hains | ||
| Company Secretary | ||
Exhibit 99.1
ASX ANNOUNCEMENT |
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Radiopharm Theranostics and Siemens Healthineers Sign Clinical Supply Agreement for RAD101 in the U.S.
Data from the interim analysis in Phase 2b trial
of RAD101 showed significant and selective tumor uptake in brain metastases,
with 90% concordance (Primary Endpoint) with MRI.
Partnership ensures sufficient supply of RAD 101 in Phase 3 registrational trial in the U.S.
Sydney, Australia. – 7 April 2026 – Radiopharm Theranostics (ASX:RAD, “Radiopharm” or the “Company”), a clinical-stage biopharmaceutical company focused on developing innovative oncology radiopharmaceuticals for areas of high unmet medical need, and Siemens Healthineers, today announced the signing of a supply agreement in which Siemens Healthineers will radiolabel and distribute RAD101 with Fluorine-18 (18F). RAD101 is Radiopharm’s novel imaging small molecule targeting fatty acid synthase (FASN) radiolabelled with Fluorine-18 for the diagnosis of suspected recurrent brain metastases from solid tumors of different origins.
“This partnership marks a milestone for Radiopharm, as we bring RAD101 closer to improving diagnostic precision for brain metastases,” said Riccardo Canevari, CEO and Managing Director of Radiopharm Theranostics. “We have made considerable progress advancing RAD101 through the clinic, and the second interim analysis showed 90% (18/20) of the patients dosed with RAD101 achieved concordance between PET imaging and MRI (the primary endpoint). The results showed significant and selective tumor uptake in the brain metastases. Images confirm metabolic activity in brain metastases compared to equivocal MRI findings. In addition, the first five patients with evaluable six-month follow-up and/or biopsy data show a positive trend for sensitivity and specificity (the secondary objectives). This partnership ensures our supply of 18F-labeled RAD101 in the U.S. for the initiation of the multi-center global Phase 3 registrational trial following our readout of topline data in the Phase 2b trial in the first half of 2026.”
The company has received U.S. Food and Drug Administration (FDA) Fast Track Designation to distinguish between recurrent disease and the treatment effect of brain metastases originating from solid tumors of different origins, including leptomeningeal disease.
Under the terms of the agreement, Siemens Healthineers will manufacture and distribute doses of 18F-labeled RAD101 to support Radiopharm’s upcoming Phase 3 registrational trial in the U.S.
“As the leader in PET imaging solutions, we are pleased to partner with Radiopharm Theranostics to provide our reliable and specialized manufacturing capabilities,” said Barry Scott, Head of Radiopharma at Siemens Healthineers. “With our large national network of radiopharmacies in the U.S., we are uniquely qualified and well-equipped to deliver RAD101 as well as other novel PET biomarkers to assist in the fight against challenging diseases such as brain metastases, a condition that more than 300,000 people are diagnosed with in the U.S. each year.”
Radiopharm Theranostics Limited
Suite 1, Level 3, 62 Lygon Street, Carlton South VIC 3053 Australia
ABN: 57 647 877 889
ASX ANNOUNCEMENT |
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About Radiopharm Theranostics
Radiopharm Theranostics is a clinical stage radiotherapeutics company developing a world-class platform of innovative radiopharmaceutical products for diagnostic and therapeutic applications in areas of high unmet medical need. Radiopharm is listed on ASX (RAD) and on NASDAQ (RADX). The company has a pipeline of distinct and highly differentiated platform technologies spanning peptides, small molecules and monoclonal antibodies for use in cancer. The clinical program includes one Phase 2 and five Phase 1 trials in a variety of solid tumor cancers including lung, breast, and brain metastases. Learn more at radiopharmtheranostics.com.
Authorised on behalf of the Radiopharm Theranostics board of directors by Chairman Paul Hopper.
For more information:
Riccardo Canevari
CEO & Managing Director
P: +1 862 309 0293
E: rc@radiopharmtheranostics.com
Anne Marie Fields
Precision AQ (Formerly Stern IR)
E: annemarie.fields@precisionaq.com
Paul Hopper
Executive Chairman
P: +61 406 671 515
E: paulhopper@lifescienceportfolio.com
Media
Matt Wright
NWR Communications
P: +61 451 896 420
E: matt@nwrcommunications.com.au
Radiopharm Theranostics Limited
Suite 1, Level 3, 62 Lygon Street, Carlton South VIC 3053 Australia
ABN: 57 647 877 889