FDA to Review Blue Earth Diagnostics' Emerging PSMA/PET Agent for Prostate Cancer

One prospective multicenter study found the radiohybrid prostate-specific membrane antigen (PSMA) agent 18F-rhPSMA-7.3 had an 83 percent detection rate in nearly 400 men with suspected prostate cancer.

Could an emerging agent have an impact in PET imaging of patients with prostate cancer?

Based upon findings from recent studies, including two prospective phase 3 trials, Blue Earth Diagnostics has announced that their new drug application (NDA) for 18F-rhPSMA-7.3, a prostate-specific membrane antigen (PSMA)-targeted agent for prostate cancer imaging, has been accepted for review by the Food and Drug Administration (FDA).1

Consisting of a PSMA-targeted receptor ligand that is internalized by prostate cancer cells, 18F-rhPSMA-7.3 may be labeled with the 18F radioisotope for positron emission tomography (PET) imaging, according to Blue Earth Diagnostics, a subsidiary of Bracco Imaging.

The radiohybrid PSMA agent could be a significant advance for facilitating timely staging and treatment of prostate cancer, according to Eugene Teoh, MBBS, MRCP, FRCR, D.Phil, the chief medical officer of Blue Earth Diagnostics.

“Prostate cancer is a leading cause of male cancer-related death worldwide, and accurate localization and staging of the disease is critical in establishing optimal medical management strategies,” said Dr. Teoh. “We believe that the performance of 18F-rhPSMA-7.3, its high PSMA binding affinity and potential for low bladder activity will make it a valuable diagnostic tool that is radiolabeled with 18F for high image quality and readily available patient access.”

In research from a phase 3, prospective multicenter study (SPOTLIGHT) involving 398 men with suspected prostate cancer, 18F-rhPSMA-7.3 had an overall detection rate of 83 percent. For patients who had one or more true positive lesion(s), 18F-rhPSMA-7.3 had a patient-level correct detection rate (CDR) of 56.8 percent, according to the study. The study researchers noted the patient-level CDR was 81.2 percent in a subset of those with a histopathology-only standard of truth (SoT).2

“Together, these data support the clinical utility of 18F-rhPSMA-7.3 PET in men with recurrent prostate cancer across a wide PSA (prostate-specific antigen) range,” wrote study author David M. Schuster, M.D., FACR, the director of the Division of Nuclear Medicine and Molecular Imaging at the Emory University School of Medicine.


1. Blue Earth Diagnostics. Blue Earth Diagnostics announces FDA acceptance of new drug application for 18F-rhPSMA-7.3, a radiohybrid prostate-specific membrane antigen-targeted PET imaging agent for prostate cancer. Business Wire. Available at: https://www.businesswire.com/news/home/20220927005159/en/Blue-Earth-Diagnostics-Announces-FDA-Acceptance-of-New-Drug-Application-for-18F-rhPSMA-7.3-a-Radiohybrid-Prostate-Specific-Membrane-Antigen-Targeted-PET-Imaging-Agent-for-Prostate-Cancer . Published September 27, 2022. Accessed September 27, 2022.

2. Schuster DM, SPOTLIGHT Study Group. Detection rate of 18F-rhPSMA-7.3 PET in patients with suspected prostate cancer recurrence: results from a phase 3, prospective, multicenter study (SPOTLIGHT). J Clin Oncol. 2022;40(6); suppl, 9-9. Available at: https://ascopubs.org/doi/abs/10.1200/JCO.2022.40.6_suppl.009 . Accessed September 27, 2022.