PeptiDream Inc., PDRadiopharma Inc., and Curium Group have initiated a registrational Phase 2 clinical trial in Japan for 64Cu-PSMA-I&T, a PET radiopharmaceutical targeting prostate-specific membrane antigen (PSMA) expressed on prostate cancer cells. The companies announced the enrollment of the first patient on October 15, 2025, marking a significant milestone in bringing advanced radiopharmaceutical diagnostics to Japanese prostate cancer patients.
Trial Design and Patient Population
The open-label, single-arm Phase 2 study (jRCT: 2031250225) will evaluate the sensitivity, specificity, and safety of 64Cu-PSMA-I&T as a diagnostic PET imaging agent. The trial will enroll approximately 70 patients who have been newly diagnosed with unfavorable intermediate, high or very high-risk prostate cancer and are scheduled for prostatectomy with pelvic lymph node dissection.
The study is being conducted as a registrational trial in Japan and will utilize bridging data from Curium's ongoing global clinical trials. 64Cu-PSMA-I&T is labeled with the radioisotope Copper-64 and is being developed alongside its therapeutic counterpart, 177Lu-PSMA-I&T.
Addressing Unmet Medical Need in Japan
Prostate cancer represents a significant healthcare burden in Japan, with approximately 90,000-100,000 new cases diagnosed annually according to the National Cancer Center Japan. Patients with metastatic castration-resistant prostate cancer have an overall survival rate of approximately three years in clinical trial settings, and even shorter in real-world practice, highlighting the substantial unmet medical need for improved therapies.
"There is demand in Japan for PSMA PET diagnosis, as many urologists wish to use this imaging modality in clinical practice," commented Masato Murakami, President of PDRadiopharma and CMO of PeptiDream. "In collaboration with Curium, we aim to address this need and utilize radiopharmaceuticals to provide new medical treatments for patients."
Global Clinical Development Progress
The development program builds on encouraging results from Curium's global trials. For the therapeutic agent 177Lu-PSMA-I&T, a PSMA-targeting ligand conjugated with the radioisotope Lutetium-177, the global Phase 3 ECLIPSE trial (NCT05204927) met its primary endpoint, demonstrating a statistically significant and clinically meaningful benefit for patients with metastatic castration-resistant prostate cancer.
For the diagnostic agent 64Cu-PSMA-I&T, ongoing trials include the SOLAR RECUR trial (NCT06235099) for diagnosing biochemical recurrence of prostate cancer and the SOLAR STAGE trial (NCT06235151) for men newly diagnosed with unfavorable intermediate to very high-risk prostate cancer electing to undergo surgery. The first-in-human Phase 1/2 SOLAR trial met its co-primary endpoints of region-level correct localization rate and patient-level correct detection rate in patients with histologically-proven metastatic prostate cancer.
Strategic Partnership and Future Plans
The development is conducted under a strategic collaboration between PDRadiopharma, a wholly owned subsidiary of PeptiDream, and Curium Group. Under the partnership terms, the companies will jointly collaborate on clinical development activities of both 64Cu-PSMA-I&T and 177Lu-PSMA-I&T in Japan, with PDRadiopharma leading regulatory filing, manufacturing, commercialization, and distribution activities in the country.
Curium will continue to lead global development of both agents and support PDRadiopharma through technology transfer to establish manufacturing lines in Japan, including a high throughput Copper-64 manufacturing line based on Curium's proprietary technology.
In parallel with the diagnostic trial, a clinical trial for 177Lu-PSMA-I&T as a therapeutic agent is being planned to evaluate its efficacy and safety in patients with metastatic castration-resistant prostate cancer.
"Targeted radiopharmaceuticals are rapidly revolutionizing how we both diagnose and treat cancer," said Patrick C. Reid, President & CEO of PeptiDream. "At PeptiDream and PDRadiopharma we are focused on expanding our pipeline of these targeted therapies, and we are thrilled to be able to accelerate those efforts by partnering with Curium to bring their prostate cancer targeting radiopharmaceuticals to patients in Japan."
Renaud Dehareng, CEO of Curium Group, added: "Conducting these registrational trials, in partnership with PeptiDream and PDRadiopharma, marks a significant milestone in our mission to expand access to cutting-edge radiopharmaceuticals to patients with prostate cancer across Asia. By combining Curium's global development expertise with PDRadiopharma's deep local knowledge and infrastructure, we are well-positioned to deliver transformative solutions to prostate cancer patients in Japan."
