Telix Pharmaceuticals has dosed the first patient in the randomized expansion phase of its pivotal ProstACT Global Phase 3 trial for TLX591, targeting advanced prostate cancer. The trial is expanding globally, with regulatory submissions underway in the US and Europe.
- First patient dosed in Part 2 of ProstACT Global Phase 3 trial
- Trial evaluates TLX591 combined with standard of care in metastatic castration resistant prostate cancer
- Global expansion includes Australia, New Zealand, Canada, and planned sites in US, China, Japan, and Europe
- Preliminary Part 1 data to be submitted to FDA and EMA for regulatory engagement
- TLX591 shows differentiated safety profile with minimal kidney toxicity and reduced salivary gland uptake
Milestone Achieved in Prostate Cancer Trial
Telix Pharmaceuticals Limited has reached a significant milestone by dosing the first patient in Part 2 of its ProstACT Global Phase 3 trial. This randomized treatment expansion phase evaluates TLX591, a novel prostate cancer therapy, in patients with metastatic castration resistant prostate cancer (mCRPC). The initial dosing took place at the Australian Prostate Centre in Melbourne, marking the transition from the safety and dosimetry lead-in phase to a larger, randomized study.
A Global Endeavor with Regulatory Momentum
The ProstACT Global trial is notable for its international scope, currently recruiting patients across Australia, New Zealand, and Canada, with plans to extend into the United States, China, Japan, Singapore, South Korea, Türkiye, the United Kingdom, and the European Union. Telix has confirmed it will submit Part 1 data to the US Food and Drug Administration (FDA) to secure clearance for US site expansion, while also preparing a clinical trial application for the European Medicines Agency (EMA) to enable entry into EU countries. This broad geographic footprint underscores Telix’s ambition to establish TLX591 as a global therapeutic option.
Innovative Therapy with Promising Safety Profile
TLX591 is a PSMA-targeted radio antibody drug conjugate designed to deliver targeted radiation therapy combined with standard of care treatments such as abiraterone, enzalutamide, or docetaxel. Unlike other PSMA-targeted radioligand therapies, TLX591’s large molecular weight results in clearance through the liver rather than the kidneys, significantly reducing the risk of kidney toxicity. Additionally, it shows minimal uptake in salivary and lacrimal glands, potentially lowering the incidence of dry mouth and dry eyes; common side effects that have limited the tolerability of competing therapies.
Looking Ahead to Data and Regulatory Engagement
Telix’s Group Chief Medical Officer, Dr. David N. Cade, emphasized the importance of this dosing milestone as a key step toward advancing their late-stage prostate cancer pipeline. The company plans to present preliminary results from Part 1 of the study to both the FDA and EMA in the coming months, which will be critical for regulatory feedback and the potential acceleration of trial expansion. These data will be closely watched by investors and clinicians alike, as they will provide early insights into the therapy’s efficacy and safety in a larger patient population.
Strategic Implications for Telix and the Market
With TLX591 still awaiting marketing authorization, the successful progression of the ProstACT Global trial is essential for Telix’s commercial ambitions. The differentiated safety profile and global trial footprint position TLX591 as a potentially competitive option in the crowded prostate cancer treatment landscape. However, the ultimate impact will depend on forthcoming clinical data and regulatory decisions, which will shape the therapy’s path to market and adoption.
Bottom Line?
Telix’s ProstACT trial expansion marks a pivotal step, but upcoming data and regulatory reviews will define TLX591’s future.
Questions in the middle?
- When will Telix publicly release the preliminary Part 1 data and what will it reveal about TLX591’s efficacy?
- How will regulatory agencies in the US and Europe respond to the Part 1 data and trial expansion plans?
- Can TLX591’s safety advantages translate into a meaningful clinical and commercial edge over existing PSMA-targeted therapies?