ASX ANNOUNCEMENT 10 DECEMBER 2024 Completion of Preclinical Data Package for KLK3-Targeting Radiotherapeutic (RAD 402) Successful completion of preclinical studies with 161 Tb-labelled RAD 402 demonstrating safety and a

Preclinical Data Package for KLK3-Targeting Radiotherapeutic (RAD 402)

Sydney, Australia - 10 December 2024 - 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, is pleased to announce the completion of a comprehensive preclinical

proof-of-concept dataset for its proprietary Kallikrein Related Peptidase 3 (KLK3)-targeting radiotherapeutic, RAD 402.

The preclinical toxicology reported positive data, with no observed

adverse effects. Biodistribution studies of 161Tb-RAD 402 in mouse xenografts showed high tumor

targeting, limited kidney and bone marrow uptake, and a hepatic excretion profile as expected for a monoclonal antibody. The safety findings

from the toxicology and biodistribution studies provide a strong rationale for First-In-Human (FiH) clinical studies.

GMP manufacturing of RAD 402 and the conjugate are currently ongoing

and are expected to be completed in Q1 2025. Radiopharm's clinical development plans for RAD 402 continue to advance, and the Company

is on track to commence the Phase I FiH study in H2 2025.

KLK3 is expressed in the prostate, and most adenocarcinomas of the

prostate, including their metastases. Prostate Specific Antigen (PSA), a widely used biomarker to detect prostate cancer, is encoded

by the KLK3 gene. RAD 402 is an anti-KLK3 monoclonal antibody, labelled with the radionuclide Terbium-161 (Tb-161). Compared to Lutetium-177,

Tb-161 emits additional Auger and conversion electrons alongside its -radiation, with potentially improved antitumoral therapeutic

is an ongoing unmet need for next-generation radiotherapeutisc in advanced prostate cancer," said

Riccardo Canevari, CEO and Managing Director of Radiopharm Theranostics. "RAD 402 has been specifically designed as a next-generation

radiotherapeutic with a novel target and isotope, reinforcing its first-in-class potential as a novel treatment option in advanced prostate

cancer. We believe that our preclinical data reaffirms our clinical development strategy for RAD 402 and provide translational support

for advancing this program into FiH studies."

Radiopharm Theranostics

Suite 1, Level 3, 62 Lygon Street, Carlton South VIC 3053 Australia

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 has been listed on ASX (RAD) since November 2021. The company has a deep pipeline of highly differentiated

molecules spanning peptides, small molecules and monoclonal antibodies for use in cancer, in pre-clinical and clinical stages of development.

The pipeline has been built based on the potential to be first-to-market or best-in-class. The clinical program includes one Phase II

and two Phase I trials in a variety of solid tumour cancers including brain, lung, breast and pancreas. Learn more at radiopharmtheranostics.com.

Authorised on behalf of the Radiopharm Theranostics Board of Directors

by Executive Chairman Paul Hopper.

For more information:

CEO & Managing Director

E: rc@radiopharmtheranostics.com

E: matt@nwrcommunications.com.au

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Website - https://radiopharmtheranostics.com/

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Radiopharm Theranostics

Suite 1, Level 3, 62 Lygon Street, Carlton South VIC 3053 Australia