NEW YORK – Blue Earth Diagnostics on Tuesday said the US Food and Drug Administration approved its prostate-specific membrane antigen (PSMA)-targeted PET imaging agent Posluma (flotufolastat F 18) for detecting prostate cancer metastasis.
Blue Earth, based in Oxford, UK, said Posluma is the first FDA-approved PSMA-targeted imaging agent developed with its proprietary radiohybrid technology. The imaging agent comprises a PSMA-targeting domain and a fluorine-18 label that facilitates PET imaging.
Posluma is indicated for PET imaging of PSMA-positive lesions in prostate cancer patients with suspected metastasis who are candidates for initial definitive therapy or whose cancers are suspected to have recurred based on elevated serum prostate-specific antigen (PSA) levels.
The FDA approved the imaging agent after reviewing data from the Phase III LIGHTHOUSE and SPOTLIGHT trials. In LIGHTHOUSE, Posluma had a specificity of 96 percent and sensitivity of 24 percent for detecting pelvic lymph node metastases in men newly diagnosed with prostate cancer who were planning to undergo radical prostatectomy.
In the 389-patient SPOTLIGHT trial, the patient-level correct detection rate for Posluma among those with prostate cancer recurrence was 56.8 percent. Additionally, Blue Earth reported in April that the overall patient-level detection rate for Posluma was 99 percent in a subgroup of patients who had undergone primary radiation therapy. The firm included this data in its regulatory application for the imaging agent.
Up to 25 percent of patients with primary prostate cancer may have regional pelvic lymph node metastases, which are associated with a high risk of recurrence and lower overall survival. "Conventional imaging techniques such as CT and MRI are limited in the information they may provide," Brian Chapin, an associate professor of urology at MD Anderson Cancer Center and an investigator in the LIGHTHOUSE trial, said in a statement.
Chapin noted that the LIGHTHOUSE study involved unfavorable intermediate, high, and very high-risk prostate cancer patients scheduled for radical prostatectomy plus pelvic lymph node dissection prior to Posluma PET imaging. "The study showed that Posluma PET provided clinically valuable information prior to surgery that would likely result in management changes for these patients," he said.