First Patients Dosed in OPTIMAL-e Trial for Earlier Stage Prostate Cancer

First patients dosed in OPTIMAL-e 1 Phase 2 study evaluating TLX597-Tx for metastatic hormone-sensitive prostate cancer at St Vincent’s Hospital Sydney. OPTIMAL-e will evaluate TLX597-Tx in earlier prostate cancer treatment setting, building on the OPTIMAL-PSMA 2 study which recently completed patient enrollment. TLX597-Tx is Telix’s next generation PSMA 3 -targeting small molecule radioligand therapy candidate designed to improve efficacy and quality of life in earlier-stage prostate cancer. MELBOURNE, Australia and INDIANAPOLIS, July 16, 2026 (GLOBE NEWSWIRE) -- Telix Pharmaceuticals Limited (ASX: TLX, NASDAQ: TLX, “Telix”) and St Vincent’s Hospital today announced that the first patients have been dosed with TLX597-Tx ( 177 Lu-DOTA-HYNIC-panPSMA) in the OPTIMAL-e trial, led by Professor Louise Emmett for patients with metastatic hormone-sensitive prostate cancer (mHSPC) at St Vincent’s Hospital in Sydney, Australia. OPTIMAL-e is a single-arm, open-label trial, evaluating adaptive-dosed TLX597-Tx in combination with androgen deprivation therapy (ADT) and an androgen receptor pathway inhibitor (ARPI) in men with mHSPC. The study will evaluate the impact of TLX597-Tx on PSA 4 response rate in an earlier treatment setting, assessing its potential to improve both the depth and durability of PSA response, while further evaluating the safety of dose intensification. TLX597-Tx is a highly-targeted next generation small molecule RLT 5 designed to improve efficacy and quality of life in earlier-stage metastatic prostate cancer. It has demonstrated a favorable biodistribution and dosimetry profile in prior studies including OPTIMAL-PSMA 6 , suggesting low exposure to salivary glands and the kidneys, the healthy organs of concern with PSMA RLT, and high uptake in PSMA-expressing tumors. Louise Emmett, MD, Director of Theranostics and Nuclear Medicine, St. Vincent’s Hospital, and Lead Investigator of the OPTIMAL-e study, said, “I am excited to lead the OPTIMAL-e trial, which is evaluating an adaptive treatment approach designed to tailor therapy to each patient's response. By using PSMA-PET 7 imaging and PSA measurements to monitor disease burden, treatment can be continued when the PSMA target persists, and paused when there is a significant reduction in tumor burden. This individualized strategy aims to maintain disease control while minimizing unnecessary treatment exposure, with the potential to keep patients in a low-volume disease state for longer and support quality of life. The findings from OPTIMAL-e may help shape future treatment strategies and advance precision medicine for men living with prostate cancer.” David N. Cade, MD, Group Chief Medical Officer, Telix, said, "The initiation of OPTIMAL-e marks an important evolution of PSMA-targeted radioligand therapy for earlier metastatic prostate cancer, where maintaining quality of life is paramount. While the currently approved radioligand therapy has demonstrated a modest improvement in overall survival in advanced-stage disease, we believe earlier intervention may offer the potential to further improve outcomes and prolong quality of life for patients." TLX597-Tx has not received marketing authorization in any jurisdiction. About OPTIMAL-e OPTIMAL-e is a Phase 2, non-randomized pilot study evaluating adaptive-dosed TLX597-Tx ( 177 Lu-DOTA-HYNIC-panPSMA) in combination with ADT and an ARPI in patients with metastatic hormone-sensitive prostate cancer (mHSPC). Adaptive dosing of 177 -Lu-PSMA is the concept of only treating if the PSMA target is persistent, while pausing treatment if there is a marked reduction in the tumor target, with re-treatment at first confirmed PSA rise (once the target has returned). The study is invest...