NCT05902247

Actium-225-Prostate Specific Membrane Antigen Imaging & Therapy

Phase I Dose Escalation Study to Evaluate Tolerability and Safety of 225Ac-PSMA I&T in Patients With Metastatic Prostate Cancer

• Status: Unknown
• Phase: Phase 1
• Study type: Interventional
• Enrollment: 30 (estimated)
• Sponsor: Erasmus Medical Center · Academic / Other
• Sex: Male
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

225Ac-PSMA I\&T is a radiopharmaceutical for therapy of prostate cancer. PSMA is overexpressed on prostate cancer cells. Actium-225 is an alpha emitting radionuclide. When PSMA I\&T is labelled with Actium-225, it can be applied as therapy for prostate cancer.

Detailed description

Rationale: 225Ac-PSMA I\&T is a radiopharmaceutical for therapy of prostate cancer. PSMA is overexpressed on prostate cancer cells. Actium-225 is an alpha emitting radionuclide. When PSMA I\&T is labelled with Actium-225, it can be applied as therapy for prostate cancer. Objective: To evaluate the tolerability and safety of 225Ac-PSMA I\&T in patients with metastatic prostate cancer and recommend a dose for further phase 2 studies. Study design: A clinical prospective, single-center, single-arm, phase I dose escalation therapy study. Study population: Up to 30 patients with advanced metastatic castration-resistant prostate cancer (mCRPC). Intervention: Patients with advanced mCRPC will receive therapy with 225Ac-PSMA I\&T. The first dose-level will not exceed 8 megabecquerel (MBq), as this is reported in the literature as a save activity for treatment. A Positron Emission Tomography - Magnetic Resonance Imaging (PET-MRI) with Gallium-68-PSMA I\&T (68Ga) will be performed to calculate the precise dose-level needed and as a verification the precise dose-level will be compared with the dose-level of 8 MBq. In the first week after therapy, the PET-MRI will be repeated to observe any effects of the alpha radiation on the metastases and observe the potential changes in 68Ga-PSMA I\&T uptake. Eight weeks after the first cycle, patients will receive the second cycle of 225Ac-PSMA I\&T. If no Dose Limiting Toxicity (DLT) occurs, the dose can be increased for the next DL. If a DLT occurs, the cohort will be expanded to 6 patients. After establishing the recommended dose, an expansion cohort will be opened with a total of 12 patients. Main study endpoints: To investigate the safety, tolerability and biochemical effects of 225Ac-PSMA I\&T injected in patients with metastatic prostate cancer. Primary objective: \- To assess the safety and tolerability of 225Ac-PSMA I\&T administered intravenously Secondary objectives: * To predict and calculate the absorbed-dose in critical organs (e.g. salivary glands, kidneys, bone marrow) by 68Ga-PSMA I\&T PET-MRI * To evaluate the effects of the radionuclide therapy on metastases in the days after therapy using 68Ga-PSMA I\&T PET-MRI * To evaluate the biochemical effects of 225Ac-PSMA I\&T therapy in patients with metastatic prostate cancer

Conditions

• Prostatic Neoplasms, Castration-Resistant

Interventions

Type	Name	Description
RADIATION	Radionuclide Therapy	To evaluate the tolerability and safety of 225Ac-PSMA I\&T in patients with metastatic prostate cancer

Timeline

• Start date: 2021-12-29
• Primary completion: 2025-12-29
• Completion: 2025-12-29
• First posted: 2023-06-13
• Last updated: 2023-06-13

Locations

1 site across 1 country: Netherlands