Radiopharm Theranostics Announces Concurrent US$4.1 Million Registered Direct Offering and Up To Additional A$12.7 (US$8.9) Million Australian Placement and Share Purchase Plan

Radiopharm Theranostics Limited (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 announces that it has entered into a Securities Purchase Agreement (“SPA”) with certain U.S. accredited institutional investors to issue, in a registered direct offering, 1,281,646 American Depositary Shares (“ADSs”), representing 384,493,800 ordinary shares (with each ADS representing 300 ordinary shares) of the Company, at an offering price of US$3.16 per ADS, to raise aggregate gross proceeds of approximately US$4.1 million, before deducting the placement agent fees and other offering expenses payable by the Company.

In a concurrent private placement and pursuant to the terms of the SPA, the Company has agreed to issue to the investors unregistered warrants to purchase up to 1,281,646 ADSs. The warrants will be exercisable on or after the effective date of shareholder approval of the issuance of the ordinary shares represented by ADSs issuable upon exercise of the warrants, will have an exercise price of US$3.79 per ADS and will expire on July 31, 2029. The offering is expected to close on or about July 28, 2026, New York Time, subject to the satisfaction of customary closing conditions. H.C. Wainwright & Co. is acting as the exclusive U.S. placement agent for the offering.

The ADSs offered in the registered direct offering (but not the warrants issued in the private placement or the ADSs underlying such warrants) are being offered by the Company pursuant to a “shelf” registration statement on Form F-3 (File No. 333-292178) that was filed with the Securities and Exchange Commission (“SEC”) on December 16, 2025, and became effective on December 23, 2025. The registered direct offering of the ADSs representing ordinary shares is being made only by means of a prospectus, including a prospectus supplement, forming a part of the effective registration statement. A final prospectus supplement and the accompanying prospectus relating to and describing the terms of the registered direct offering will be filed with the SEC. Electronic copies of the final prospectus supplement and the accompanying prospectus relating to the registered direct offering may be obtained, when available, at the SEC’s website at www.sec.gov or by contacting H.C. Wainwright & Co., LLC at 430 Park Avenue, 3rd Floor, New York, NY 10022, by telephone at (212) 856-5711 or by email at [email protected].

The warrants described above are being issued in a concurrent private placement under Section 4(a)(2) of the U.S. Securities Act of 1933, as amended (the “Securities Act”), and Regulation D promulgated thereunder and, along with the ADSs representing ordinary shares underlying the warrants, have not been registered under the Securities Act, or applicable U.S. state securities laws. Accordingly, the warrants and underlying ADSs representing ordinary shares may not be offered or sold in the United States except pursuant to an effective registration statement or an applicable exemption from the registration requirements of the Securities Act and such applicable state securities laws. In addition to the registered direct offering of ADSs and private placement of warrants in the United States, the Company has received firm commitments from Australian institutional and professional investors in a private placement for approximately A$6.7 million (US$4.7 million), before deducting the placement agent fees and other offering expenses pay...