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 February 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
EXPLANATORY NOTE
Radiopharm Theranostics Limited (the “Company”)
published one announcement (the “Public Notice”) to the Australian Securities Exchange on February 24, 2026 titled:
“RAD Doses First Patient in 177Lu-BetaBart (RV-01) Study”
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 Doses First Patient in 177Lu-BetaBart (RV-01) Study |
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: February 24, 2026 |
By: |
/s/ Phillip Hains |
| |
|
Phillip Hains |
| |
|
Company Secretary |
3
Exhibit 99.1
ASX ANNOUNCEMENT
24 February 2026 |
 |
Radiopharm
Theranostics Doses First Patient in Phase 1/2a Clinical Study of BetaBart (RV-01)
First radiotherapeutic agent developed by Radiopharm
Ventures, the joint venture between Radiopharm Theranostics and MD Anderson Cancer Center
Preclinical animal studies of BetaBart (RV-01)
have demonstrated tumor shrinkage and prolonged survival1
Sydney, Australia – 24 February 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, today announced the dosing of the
first patient in its First-In-Human (FIH) Phase 1/2a clinical trial of 177Lu-Betabart (RV-01).2
The Phase 1/2a clinical trial is a dose escalation and expansion trial
of 177Lu-BetaBart, designed to evaluate its safety, biodistribution and radiation dosimetry of 177Lu-BetaBart, along with its preliminary
anti-tumor activity. The trial will also determine the recommended dose of 177Lu-BetaBart for future studies. This agent was developed
by Radiopharm Ventures, a joint venture between Radiopharm and The University of Texas MD Anderson Cancer Center. RAD previously announced
on 28 July 2025 that the U.S. Food and Drug Administration (FDA) has provided Investigational New Drug (IND) clearance for Betabart (RV-01).
177Lu-Betabart is a Lu177-tagged engineered monoclonal antibody,
designed with a strong affinity for the 4Ig isoform of B7-H3. B7-H3 is an immune checkpoint molecule that is overexpressed across several
tumor types and has emerged as a compelling target for antibody-based cancer immunotherapy.
“Dosing of the first patient in the Phase 1/2a trial of 177Lu-BetaBart
marks an important milestone for Radiopharm, as this is the first radiotherapeutic agent from our joint venture to enter the clinic,”
said Riccardo Canevari, CEO and Managing Director of Radiopharm Theranostics. “177Lu-BetaBart has the potential to become a highly
differentiated radiotherapeutic for patients with aggressive advanced solid tumors, and we are grateful to our collaborators and participants
in this Phase 1/2a trial.”
"We are honored to administer the first dose of 177Lu-BetaBart
in this Phase 1/2a clinical trial,” noted Brandon Mancini, MD, MBA, FACRO, Medical Director at BAMF Health. “As a leading
center for radiopharmaceutical therapeutic trials, we appreciate the opportunity to provide this novel, first-in-class radiotherapeutic
for the treatment of a variety of advanced refractory solid tumors, while offering exceptional care to our clinical trial participants.”
In preclinical studies, 177Lu-BetaBart has shown
evidence of efficacy and targeting of the specific 4Ig isoform of B7-H3, supporting its potential use in multiple indications, including
prostate, pancreatic, breast and other solid tumors.3
| 1 | https://pubmed.ncbi.nlm.nih.gov/38182652/ |
| 2 | https://clinicaltrials.gov/study/NCT07189871 |
| 3 | https://pubmed.ncbi.nlm.nih.gov/38182652/ |
Radiopharm Theranostics
Limited
Suite 1, Level 3, 62 Lygon Street, Carlton South VIC 3053 Australia
ABN: 57 647 877 889
ASX ANNOUNCEMENT
24 February 2026 |
 |
About RV-01
RV-01 is the first radiopharmaceutical therapeutic agent developed
by Radiopharm Ventures, the Joint Venture formed between Radiopharm Theranostics and The University of Texas MD Anderson Cancer Center.
RV-01 is a 177Lutetium-conjugated therapeutic that targets B7-H3, an immune checkpoint molecule that is overexpressed in several tumor
types. Multiple preclinical studies with RV-01 have shown tumor shrinkage and prolonged survival in animals treated with the radiotherapeutic
agent.
About the Phase 1/2a Clinical Trial
The FIH Phase 1/2a study (NCT07189871) is designed to establish the
safety profile, biodistribution, pharmacokinetics, and radiation dosimetry of 177Lu-Betabart (RV-01). The study aims to enroll 61 eligible
participants who have a documented history of histopathologically confirmed castrate resistant prostate cancer, colorectal cancer, non-small
cell lung cancer, small cell lung cancer, head and neck squamous cell cancer, ovarian cancer, cervical cancer, endometrial cancer, triple
negative breast cancer, or esophageal squamous cell carcinoma.
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 four 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