Two molecular imaging radiopharmaceuticals that bind specifically to prostate-specific membrane antigen (PSMA), a protein that is over-expressed on the surface of prostate cancer cells, demonstrated efficacy for diagnosing and staging prostate cancer, according to research presented at the Society of Nuclear Medicine (SNM) annual conference this week in New Orleans.
The agents, [123I]MIP-1072 and [123I]MIP-1095, were developed by Cambridge, Mass.-based Molecular Insight Pharmaceuticals. The radio-iodinated small molecules showed two of the most promising prostate tumor targeting profiles from a series of the firm’s proprietary small molecule PSMA inhibitors, according to the company.
“We know that PSMA is expressed at high levels in almost all prostate cancers, including metastatic disease, and provides an excellent molecular target for detecting this disease,” said John Babich, PhD, president and chief scientific officer of Molecular Insight. “Numerous reports also demonstrate a correlation of PSMA expression with tumor stage, progression and disease recurrence.”
Molecular targeting with small molecules may provide more effective diagnosis and monitoring of prostate cancer than currently marketed radiolabeled anti-PSMA antibodies due to their potential for high tumor uptake and rapid clearance from normal tissue, Molecular Insight reported.
The company reported that it has recently initiated a Phase 1 dosimetry clinical trial with these candidates.