Telix Pharmaceuticals launches a pivotal phase III trial for prostate cancer imaging in Japan

JAPAN—Telix Pharmaceuticals has achieved a significant milestone by dosing the first patient in its pivotal Phase III registration study evaluating TLX591-Px (Illuccix, Kit for the preparation of 68Ga-PSMA-11) for prostate cancer imaging among Japanese patients.

The dosing took place at Shonan Kamakura General Hospital in Kamakura, Japan, marking the start of a critical investigation to assess the safety and efficacy of this advanced imaging technology in the Japanese population.

Study Design and Objectives

The Illuccix Japan study operates as an open-label, multi-centre, prospective Phase III trial that will assess the performance of 68Ga-PSMA-11 positron emission tomography/computed tomography (PET/CT) in patients experiencing biochemically recurrent prostate cancer following radical prostatectomy.

The trial will enroll up to 105 Japanese men across 11 sites nationwide, with the collected data intended to support a future marketing authorisation submission for TLX591-Px in Japan.

The primary objective centers on comparing the sensitivity of 68Ga-PSMA-11 PET/CT imaging against conventional imaging methods, which include standard CT scans and bone scintigraphy, specifically in detecting metastatic lesions.

Meanwhile, secondary goals include assessing the diagnostic performance for identifying both distant and local lesions, evaluating the overall tolerability and safety profile of the imaging agent, and determining how this advanced imaging approach may influence clinical management decisions for patients.

Addressing Unmet Medical Needs

Dr David Cade, chief medical officer at Telix Group, emphasized the transformative impact of PSMA-PET imaging on prostate cancer detection and management.

He noted that this technology has fundamentally changed how clinicians detect and manage prostate cancer by providing greater accuracy and confidence in treatment planning when compared with conventional imaging methods.

However, he also highlighted a critical gap: access to this technology remains limited in much of Japan, where 68Ga-PSMA-11 has not been fully validated in the local clinical setting or across all disease stages.

Dr Cade explained that this milestone, combined with Telix’s existing compassionate use supply program designed to address unmet patient needs, brings the company significantly closer to improving access to gallium-based PSMA-PET imaging.

This advancement ultimately aims to enhance outcomes for men living with prostate cancer in Japan.

Regulatory Status and Future Developments

TLX591-Px (Illuccix) is the company’s first-generation PSMA-PET imaging agent and has received approvals in multiple markets worldwide.

However, the product currently remains investigational only in Japan, underscoring the importance of this Phase III trial in establishing its clinical utility within the Japanese healthcare system.

In June 2025, Telix introduced AlFluor, a PET radiochemistry solution based on ¹⁸F-aluminium fluoride (AlF), further expanding the company’s portfolio of advanced imaging technologies for prostate cancer detection and management.