I-labeled small molecule (MIP-1095) targeting PSMA for prostate cancer therapy

Introduction Since the prostate-specific membrane antigen (PSMA) is frequently over-expressed in prostate cancer (PCa) several PSMA-targeting molecules are under development to detect and treat metastatic castration resistant prostate cancer (mCRPC). We investigated the tissue kinetics of a small molecule inhibitor of PSMA ((S)-2-(3-((S)-1-carboxy5-(3-(4-[ 124 I]iodophenyl)ureido)pentyl)ureido)pentanedioicacid; MIP-1095) using PET/CT to estimate radiation dosimetry for the potential therapeutic use of 131 I-MIP-1095 in men with mCRPC. We also report preliminary safety and efficacy of the first 28 consecutive patients treated under a compassionateuse protocol with a single cycle of 131 I-MIP-1095. Methods Sixteen patients with known prostate cancer underwent PET/CT imaging after i.v. administration of 124 I