A Study of TRC003 in the Treatment of Patients With Progressive PSMA-positive mCRPC

This is a prospective, randomized, open-label, phase 1/2 study on adult patients with PSMA-positive metastatic castration-resistant prostate cancer. Approximately 90 eligible participants will be enrolled and randomized 1:1:1 to three dose cohorts. The first six participants in each cohort will be assessed for dose-limiting toxicity (DLT) during the first treatment cycle. Each eligible participant will receive one of the predefined doses of TRC003 (7.40, 9.25, 11.10 MBq) by intravenous infusion every 8 weeks (±1 week) for a maximum of 6 cycles if participants benefit from the treatment. All participants in this study may undergo dose modification based on the assessment of safety or efficacy by the investigators. Any adverse events (AEs) observed or reported will be recorded. Blood and urine samples will be collected after the first administration of TRC003 on 6 participants in each cohort for pharmacokinetics (blood concentration of TRC003). 2 eligible participants of each cohort (total 6 participants) will undergo SPECT/CT for dosimetry after informed consent. All participants will be assessed PSA every 4 weeks. CT with contrast /MRI and bone scan will be evaluated every 8 weeks until proved disease progression by RECIST version 1.1 and the Prostate Cancer Clinical Trials Working Group 3 (PCWG3).