Illuccix PSMA-PET Imaging Agent Receives UK Approval in Prostate Cancer

The UK Medicines and Healthcare Products Regulatory Agency has approved the kit for the preparation of gallium-68 gozetotide injection.

The United Kingdom Medicines and Healthcare Products Regulatory Agency has approved the marketing authorization application for the prostate cancer PET imaging agent TLX591-CDx (Illuccix) for the preparation of gallium-68 gozetotide injection.1

The kit, which is now approved for the detection and localization of PSMA-positive lesions in adults with prostate cancer, using PET, will be made available in the UK and Ireland.

“PSMA-PET supply shortages in the UK and Europe have escalated over the past 12 months as demand increases, which has led to delays for men in urgent need of a scan to direct clinical management. It is great news that Telix can now help address this unmet need and improve equity of access in the UK through their Illuccix imaging agent and network distribution model,” Gary Cook, MD, professor of molecular imaging at Kings College London School of Biomedical Engineering & Imaging Sciences, stated in a news release.

In 2021 the FDA approved TLX591-CDx as a radioactive diagnostic agent for PSMA-PET imaging in patients with prostate cancer who have suspected metastasis and are candidates for initial definitive therapy, and in those with suspected recurrence based on elevated serum prostate-specific antigen (PSA) level.2

The efficacy of the imaging product was evaluated in the prospective, open-label PSMA-PreRP (NCT02919111) and PSMA-BCR (NCT02918357) trials.3

The PSMA-PreRP trial enrolled 325 patients with biopsy-confirmed prostate cancer who were eligible for prostatectomy and pelvic lymph node dissection. Eligibility criteria required that all patients had serum PSA of at least 10 ng/mL, a tumor stage of cT2b or greater, or a Gleason score greater than 6. All patients received the gallium 68 gozetotide PET/CT or PET/MR from the mid-thigh to the skull base.

Among PET-positive patients irrespective of positive or negative histopathology, the positive predictive value was 61% (95% CI, 41%-81%). Patients with PET-negative disease displayed a negative predictive value of 84% (95% CI, 79%-91%).

For patients with positive histopathology, the sensitivity rate was 47% (95% CI, 29%-65%). Patients with negative histopathology experienced a specificity rate of 90% (95% CI, 84%-96%).

In the PSMA-BCR trial, 635 patients were enrolled with biochemical evidence of recurrent prostate cancer following definitive treatment. Biochemical recurrence was defined by a serum PSA of more than 0.2 ng/mL more than 6 weeks after prostatectomy or by an increase in serum PSA of at least 2 ng/mL above nadir following definitive radiation.

A total of 469 patients (74%) had 1 or more positive regions identified by TLX591-Dx. These included the bone (34%), prostate bed (25%), pelvic lymph node (25%), and extrapelvic soft tissue (17%).

Additional findings indicated that 91% (n = 192) of patients were found to be true positive in 1 or more regions against the composite reference standard (95% CI, 88%-95%). The proportion of patients who were true positive in at least 1 region fell between 82% and 97% among the pool of 9 readers from the study. Additionally, the prostate bed had the lowest proportion of true positive results at the region level, at 76% vs 96% for non-prostate regions.

“PSMA-PET imaging is one of the most important developments in prostate cancer detection in recent years and we are delighted that we can now bring Illuccix to physicians and their patients across the UK.1 A key advantage of Illuccix is that the radioisotope (gallium-68) can be produced using a generator locally, taking just a few minutes with minimal equipment. Reliable service delivery combined with greater scheduling flexibility, including in non-metropolitan locations, will benefit patients, physicians and clinical sites in the UK,” Raphaël Ortiz, chief executive officer, Telix International added.

References

  1. Illuccix approved in the United Kingdom. News release. Telix. February 12, 2025. Accessed February 13, 2025. https://ir.telixpharma.com/news-releases/news-release-details/illuccixr-approved-united-kingdom
  2. FDA approves Telix’s prostate cancer imaging product, Illuccix. News release. Telix. December 20, 2021. Accessed February 13, 2025. https://telixpharma.com/news-views/fda-approves-telixs-prostate-cancer-imaging-product-illuccix/
  3. Illuccix. Prescribing information. Telix; 2021. Accessed February 13, 2025. https://telixpharma.com/wp-content/uploads/2023/03/illuccix-prescribing-information-2.pdf