Dr. Lowentritt on broad efficacy of 18F-rhPSMA-7.3 PET in prostate cancer

In this video Benjamin Lowentritt, MD, a urologists at Chesapeake Urology Research Associates, Towson, Maryland, discusses findings from the phase 3 SPOTLIGHT trial that support the clinical utility of theradiohybrid PSMA-PET imaging agent 18F-rhPSMA-7.3 PET for a broad range of patients with recurrent prostate cancer.

The multicenter, single-arm SPOTLIGHT trial (NCT04186845) enrolled male patients who were at least 18 years of age and received prior curative intent treatment for localized prostate cancer. Patients were required to have elevated PSA levels that could indicate biochemical recurrence and be eligible for salvage therapy.

Among all patients in the trial’s efficacy evaluable population, 18F-rhPSMA-7.3 detection rates were high across all blinded central readers, with a patient-level detection rate of over 80% by majority read. The analysis from SPOTLIGHT trial that Lowentritt discusses in this video examined the impact of baseline PSA level, PSA doubling time, Gleason score, and prior therapy on 18F-rhPSMA-7.3 detection rates. In the video, Lowentritt says that, “There was an overall very high level of performance and detection rates across all of those subgroups.”

Video Transcript

What we know about patients that recur is that we do see all different patterns of recurrence, some that happen more quickly and some that happened over more of a time period. We also find the patients at different points, both specifically with their PSA levels, as well as their PSA doubling time, or they may have had a history of higher or lower grade cancer at their initial diagnosis. So, we looked at all of these in the SPOTLIGHT trial patients—we looked at the PSA level, we looked at the PSA doubling time, we looked at what their initial Gleason score was, whether they had had surgery initially or radiation initially, and there was an overall very high level of performance and detection rates across all of those subgroups. There certainly is a component of the absolute PSA level where you see the higher the PSA, the higher the detection rate, but in the entire cohort that was studied where we can assess detection rate data, using a majority read of blinded central readers, 83% of patients that were imaged had disease detected had a detection of disease. So, all of this was very positive and shows the value of having this novel PET agent in identifying sites of recurrence.

The transcript has been edited for clarity.