# EDGAR Filing Document

**Accession Number:** 0001949257
**File Stem:** 0001213900-25-049670
**Filing Date:** 2025-6
**Character Count:** 8995
**Document Hash:** f4829c5e3ef5bdfc7e1785d4be2b6032
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001213900-25-049670.hdr.sgml**: 20250602

**ACCESSION NUMBER**: 0001213900-25-049670

**CONFORMED SUBMISSION TYPE**: 6-K

**PUBLIC DOCUMENT COUNT**: 4

**CONFORMED PERIOD OF REPORT**: 20250602

**FILED AS OF DATE**: 20250602

**DATE AS OF CHANGE**: 20250602

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Radiopharm Theranostics Ltd
- **CENTRAL INDEX KEY:** 0001949257
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 000000000
- **STATE OF INCORPORATION:** C3
- **FISCAL YEAR END:** 0630

**FILING VALUES:**
- **FORM TYPE:** 6-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-41621
- **FILM NUMBER:** 251013049

**BUSINESS ADDRESS:**
- **STREET 1:** LEVEL 3, 62 LYGON STREET
- **CITY:** CARLTON VIC
- **STATE:** C3
- **ZIP:** 3053
- **BUSINESS PHONE:** 61 3 9824 5254

**MAIL ADDRESS:**
- **STREET 1:** LEVEL 3, 62 LYGON STREET
- **CITY:** CARLTON VIC
- **STATE:** C3
- **ZIP:** 3053

**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 June 2025

Commission File Number: 001-41621

**<u>RADIOPHARM THERANOSTICS LIMITED</u>**

(Name of Registrant)

**<u>Level 3, 62 Lygon Street, Carlton South, Victoria, 3053, Australia</u>**

(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**

**<u>EXPLANATORY NOTE</u>**

Radiopharm Theranostics Limited (the "Company") published one announcement (the "Public Notice") to the Australian Securities Exchange on June 02, 2025 titled:

- "RAD Reports Preclinical Lu177-B7H3-mAb Data"

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**

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| | |
|:---|:---|
| **Exhibit** <br> **Number** | **Description** |
| 99.1 | [RAD Reports Preclinical Lu177-B7H3-mAb Data](ea024418401ex99-1_radiopharm.htm) |

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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.

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| | | |
|:---|:---|:---|
|  | **RADIOPHARM THERANOSTICS LIMITED** | **RADIOPHARM THERANOSTICS LIMITED** |
| Date: June 02, 2025 | By: | /s/ Phillip Hains |
|  |  | Phillip Hains |
|  |  | Company Secretary |

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## Exhibit 99.1

**Exhibit 99.1**

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| | |
|:---|:---|
| **ASX **ANNOUNCEMENT** | ![](ex99-1_001.jpg) |

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**Radiopharm Theranostics Reports Preclinical Lu177-B7H3-mAb Data<br> Demonstrating Favourable Biodistribution and High Tumour Uptake** 

 

*Supports plans to advance the RV01 program to first-in-human therapeutic basket study in solid tumour cancers*

 

*Data completes preclinical package for Investigational New Drug submission in mid-2025 with Phase 1 therapeutic study initiation expected in 4Q25*

Sydney, Australia – 2 June 2025 – Radiopharm Theranostics (ASX: RAD, Nasdaq: RADX, "Radiopharm" or the "Company"), a clinical-stage biopharmaceutical company focused on developing innovative oncology radiopharmaceuticals for areas of high unmet medical need, today announced that preclinical data from studies with the Lu177-B7H3-monoclonal antibody RV01 demonstrated favourable biodistribution and showed that RV01 maintained high tumour uptake. In addition, the Fc region modifications of the monoclonal antibody (mAb) confirm a shorter half-life, compared to traditional mAbs. The shorter half-life and other Fc modifications have the potential to limit off-target exposure to the isotope and mitigate toxicities associated with traditional monoclonal antibody therapies.

RV01 is the Company's B7-H3-targeted radiopharmaceutical therapy designed with strong affinity for the 4Ig isoform of B7H3 that is highly expressed in tumours and not in healthy tissues, which is being developed in partnership with MD Anderson Cancer Center. The B7-H3 targeting monoclonal antibody (mAb) is designed to target various solid tumours that express the B7-H3 protein. High expression of this target is associated with a poor prognosis in many cancer types.

"We are especially pleased with these new preclinical data as they further validate earlier preclinical work that showed strong affinity to the target without the extensive circulation time of other monoclonal antibodies. Our mAb has been purposefully modified in the Fc-region with the objective of maintaining the same targeting capabilities together with a reduced half-life. Most mAbs have a typical half-life of over one week, whereas RV01 peaks within one to two days," stated Dimitris Voliotis, M.D., Chief Medical Officer of Radiopharm Theranostics.

"The antibody shows faster liver excretion in the preclinical experiments, allowing the isotope enough time to effectively target the tumor potentially without the associated toxicities. Unlike peptides or small molecules, mAbs are excreted by the liver, the most radio-resistant organ. This, combined with the faster excretion due to the shortened half-life, potentially offers important advantages compared to excretion via the kidneys, where the elimination of radiopharmaceuticalscan result in a significant potential toxicities," added Dr. Voliotis

**Radiopharm Theranostics Limited<br> Suite 1, Level 3, 62 Lygon Street, Carlton South VIC 3053 Australia<br> ABN: 57 647 877 889**

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| | |
|:---|:---|
| **ASX **ANNOUNCEMENT** | ![](ex99-1_001.jpg) |

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![](ex99-1_002.jpg)

The new preclinical data corroborate conclusions from earlier preclinical mouse studies that identified a high-affinity antibody highly selective to the cancer-specific 4Ig isoform of the B7-H3 receptor, demonstrated complete regression of established solid tumours with treatment and showed promising evidence of immune system stimulation and the ability to confer immune memory.

"This biodistribution study is the last preclinical work needed to complete the preclinical package for our Investigational New Drug Application (IND) with the U.S. Food and Drug Administration. These data allow us to confirm our guidance to file the IND-submission in mid- 2025 and to initiate our first-in-human Phase 1 basket study by the end of this year," said Riccardo Canevari, CEO and Managing Director of Radiopharm Theranostics.

**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 three Phase 1 trials in a variety of solid tumor cancers including lung, breast, and brain. Learn more at radiopharmtheranostics.com.

**Authorized on behalf of the Radiopharm Theranostics Board of Directors by Executive Chairman Paul Hopper.**

**For more information:**

**Investors:**

Riccardo Canevari<br> CEO & Managing Director<br> P: +1 862 309 0293<br> E: rc@radiopharmtheranostics.com

Anne Marie Fields

Precision AQ (formerly Stern IR)

E: annemarie.fields@precisionaq.com

**Radiopharm Theranostics Limited<br> Suite 1, Level 3, 62 Lygon Street, Carlton South VIC 3053 Australia<br> ABN: 57 647 877 889**

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| | |
|:---|:---|
| **ASX **ANNOUNCEMENT** | ![](ex99-1_001.jpg) |

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**Media:**

Matt Wright<br> NWR Communications<br> P: +61 451 896 420<br> E: matt@nwrcommunications.com.au

**Follow Radiopharm Theranostics:** 

Website – https://radiopharmtheranostics.com/<br> X – https://x.com/TeamRadiopharm<br> LinkedIn – https://www.linkedin.com/company/radiopharm-theranostics/<br> InvestorHub – https://investorhub.radiopharmtheranostics.com/

**Radiopharm Theranostics Limited<br> Suite 1, Level 3, 62 Lygon Street, Carlton South VIC 3053 Australia<br> ABN: 57 647 877 889**