Telix Pharmaceuticals Advances ProstACT Global Phase 3 Trial with First Patient Dosed in Randomized Expansion
核心洞察
Telix Pharmaceuticals has dosed the first patient in Part 2 of its ProstACT Global Phase 3 study evaluating TLX591, a PSMA (搜索)-targeted radio antibody-drug conjugate therapy for metastatic castration resistant prostate cancer (搜索).
The randomized treatment expansion will enroll approximately 490 patients across multiple countries, representing the first Phase 3 trial to combine a PSMA (搜索)-targeted rADC therapy with standard of care treatments.
TLX591 demonstrates a differentiated safety profile compared to existing PSMA (搜索)-targeted therapies, with liver clearance instead of kidney clearance and minimal salivary gland uptake reducing common adverse effects.
Telix Pharmaceuticals has achieved a significant milestone in its late-stage prostate cancer (搜索) therapeutics pipeline by dosing the first patient in Part 2 of its ProstACT Global Phase 3 study. The patient was dosed at the Australian Prostate Centre (搜索) in Melbourne, Australia, marking the beginning of the randomized treatment expansion phase evaluating TLX591 (lutetium (177Lu) rosopatamab tetraxetan) in patients with metastatic castration resistant prostate cancer (搜索) (mCRPC (搜索)).
First-in-Class Combination Approach
ProstACT Global represents the first Phase 3 trial to combine a PSMA (搜索)-targeted radio antibody-drug conjugate (rADC) therapy administered together with Standard of Care treatments versus SOC alone. The standard of care options include abiraterone, enzalutamide, or docetaxel. Part 2 of the study will enroll approximately 490 patients and is currently recruiting patients in Australia, New Zealand, and Canada.
The study has received approvals to commence in China, Japan, Singapore, South Korea, Turkey, and the United Kingdom. As part of the global expansion strategy, Telix will submit Part 1 data to the U.S. Food and Drug Administration (FDA) to enable clearance for expanding Part 2 to U.S. sites. Additionally, the company will file a clinical trial application with the European Medicines Agency (EMA) to enable expansion into EU sites.
Differentiated Safety Profile
TLX591 demonstrates distinct targeting and pharmacology compared to other PSMA (搜索)-targeted small peptide radioligand therapies. The antibody approach offers several potential advantages in terms of safety profile. Collective long-term follow-up of patients administered with TLX591 has not observed significant acute or delayed kidney toxicity, as the agent is cleared through the liver instead of the kidneys.
Due to its large molecular weight, TLX591 also demonstrates minimal salivary and lacrimal gland uptake, potentially reducing dry mouth and dry eyes, which are common adverse effects of existing PSMA (搜索)-targeted radioligand therapies.
Study Design and Patient Population
ProstACT Global is an international, multicenter trial conducted in two parts. Part 1 consisted of a safety and dosimetry lead-in with 30 patients, which has completed target enrollment. Part 2 involves a 2:1 randomized global expansion with an overall target enrollment of approximately 490 patients.
Eligible patients must have confirmed progressive mCRPC (搜索) assessed with a 68Ga-PSMA (搜索)-11 PET imaging agent following prior treatment with an androgen receptor pathway inhibitor (ARPI). The imaging agents used include Illuccix or Gozellix (搜索), kits for the preparation of gallium-68 (68Ga) gozetotide injection.
Regulatory Strategy and Timeline
Dr. David N. Cade, Group Chief Medical Officer at Telix, commented on the milestone: "Dosing the first patient into Part 2 of the randomized treatment expansion of ProstACT Global trial is a significant milestone for Telix's late-stage prostate cancer (搜索) therapeutics pipeline. We look forward to presenting the preliminary data from Part 1 of the study to the FDA and EMA in the coming months."
As previously agreed with the FDA, Telix will submit Part 1 data to enable clearance for expanding Part 2 of the trial to U.S. sites. A public disclosure of preliminary results from Part 1 of the study will be aligned to engagement with the FDA.
The advancement of TLX591 through Phase 3 development represents a significant step forward in addressing unmet medical needs for patients with metastatic castration resistant prostate cancer (搜索), particularly given its potentially differentiated safety profile compared to existing PSMA (搜索)-targeted therapies.