Full Press Release Details
Melbourne (Australia) and Indianapolis (United States) | 17 December 2025
Telix today provides an update to confirm the current status of the ProstACT Global Phase 3 study of its lead prostate cancer therapy candidate TLX591 (lutetium ( 177 Lu) rosopatamab tetraxetan) in patients with metastatic castration resistant prostate cancer (mCRPC). This announcement is provided in response to inaccurate information in market circulation.
ProstACT Global is the first Phase 3 trial to combine a PSMA [1] -targeted radio antibody-drug conjugate (rADC) therapy administered together with Standard of Care (SOC; abiraterone, enzalutamide or docetaxel) versus SOC alone. Telix confirms that it has completed patient enrolment into Part 1 of the study, a safety and dosimetry lead-in, in accordance with the study protocol.
Preparation is now underway to complete data lock and read-out. This includes data from each of the three cohorts in Part 1, including the docetaxel cohort which was the final cohort to complete enrolment. As previously disclosed [2] , data from Part 1 will be presented to the United States (U.S) Food and Drug Administration (FDA) to ascertain eligibility for U.S. patients to participate in the Part 2 (randomized treatment expansion) portion of the study. Preliminary results from Part 1 of the study will be publicly disclosed at the time of readout and engagement with the FDA.
In accordance with the study protocol, an Independent Data Monitoring Committee (IDMC) has reviewed the available data in Part 1 of the study and, per the IDMC charter, has recommended that the study proceed to Part 2. Accordingly, Telix has advanced the study into Part 2, in jurisdictions where it has obtained approval from health authorities. Part 2 has been initiated on the basis that Part 1 indicates no unexpected safety or clinical characteristics that differ from prior experience.
Part 2 of ProstACT Global has dosed its first patients, and is approved and open for enrolment in Australia, New Zealand and Canada. The study has also received regulatory approval to commence in China, Singapore, Türkiye, the United Kingdom, South Korea and Japan [3] . As part of the further global expansion of the trial, Telix intends to file a clinical trial application (CTA) with the European Medicines Agency (EMA) to enable expansion into EU sites.
TLX591 has not received a marketing authorization in any jurisdiction.
[1] Prostate-specific membrane antigen.
[2] Telix ASX disclosure 8 December 2025.
[3] Japanese regulator Pharmaceuticals and Medical Devices Agency (PMDA) has granted approval for a Japan-specific Part 1 in nine patients, prior to commencing Part 2.