FDA Approves PSMA PET Imaging Agent TLX007-CDx for Prostate Cancer

FDA

The FDA has approved the next-generation prostate-specific membrane antigen (PSMA)–PET imaging agent TLX007-CDx, a kit for the preparation of gallium-68 (68Ga) gozetotide injection (Gozellix) for use in PET scanning of PSMA-positive lesions in men with prostate cancer who have suspected metastasis and are candidates for initial definitive therapy, and those with suspected recurrence based on elevated serum prostate-specific antigen (PSA) level.1

The approval is supported by data from the PSMA-PreRP trial (NCT03368547 and NCT02919111) and the PSMA-BCR trial (NCT02940262 and NCT02918357) for the initial definitive therapy and PSA recurrence indications, respectively. Notably, both studies evaluated another formulation of 68Ga gozetotide.2

“Securing FDA approval for Gozellix is a major win for [patients with] prostate cancer, who gain enhanced access to state-of-the-art 68Ga PSMA-PET imaging," Kevin Richardson, chief executive officer of Telix Precision Medicine, stated in a news release.1 "Telix continues to invest in innovation across our portfolio, and Gozellix is a testament to this continuous improvement approach. With the launch of Gozellix, our team is excited to be bringing the new generation of prostate cancer scanning to more American men, delivered with the reliability, service, and flexibility that customers have come to expect from Telix.”

PSMA-PreRP Breakdown

The prospective, open-label study enrolled patients (n = 325) with biopsy-proven prostate cancer who were considered candidates for prostatectomy and pelvic lymph node dissection.2 Key inclusion criteria consisted of a serum PSA level of at least 10 ng/mL; a tumor stage of cT2b or greater; or a Gleason score greater than 6.

All patients received a single administration of 68Ga gozetotide. Thirty-eight percent of enrolled patients (n = 128) underwent prostatectomy and template pelvic lymph node dissection and had sufficient histopathology data for evaluation.

Findings showed that among patients who were positive for pelvic lymph node metastasis on a standard PET scan (n = 23), 14 were found to be positive using 68Ga gozetotide, translating to a positive predictive value of 61% (95% CI, 41%-81%). In patients who were negative on conventional PET scan (n = 100), 16 patients were positive for pelvic lymph node metastasis using 68Ga gozetotide, translating to a negative predictive value of 84% (95% CI, 79%-91%).

PSMA-BCR Overview

The prospective, open-label PSMA-BCR trial enrolled patients (n = 635) who had biochemically recurrent prostate cancer following definitive therapy, which was defined as a serum PSA level greater than 0.2 ng/mL more than 6 weeks after prostatectomy or by an increase in serum PSA level of at least 2 ng/mL above nadir after definitive radiotherapy.

All patients received a single administration of 68Ga gozetotide, and 210 had composite reference standard information collected in a PET-positive region to comprise the evaluable population.

In the evaluable population, 91% of patients were true positive in at least 1 region against the composite reference standard (95% CI, 88%-95%). Additionally, the proportion of patients who were true positive in 1 or more regions ranged from 82% to 97% among the 9 readers in the study.

Additional Prescribing Information for TLX007-CDx

The recommended amount of radioactivity for adult patients is 111 MBq to 259 MBq, or 3 mCi to 7 mCi, as a bolus intravenous injection. Imaging is recommended 50 to 100 minutes following the administration of TLX007-CDx, and the scan should begin caudally and proceed cranially.

The most common adverse effects (AEs) reported with 68Ga gozetotide include nausea, diarrhea, and dizziness; however, these AEs were all reported at rates of less than 1%.

References

1. FDA approves new prostate cancer imaging agent Gozellix. News release. Telix. March 20, 2025. Accessed March 20, 2025. https://telixpharma.com/news-views/fda-approves-new-prostate-cancer-imaging-agent-gozellix/
2. Gozellix. Prescribing Information. Telix. March 2025. Accessed March 20, 2025. https://telixpharma.com/wp-content/uploads/2025/03/Gozellix-prescribing-information.pdf