At the 2023 ESMO Congress, Oliver Sartor, MD, Mayo Clinic, Rochester, Minnesota, described results from the phase 3 PSMAfore trial evaluating ¹⁷⁷Lu-PSMA-617 vs androgen receptor-directed therapy for patients with metastatic castration-resistant prostate cancer. While previous trials have investigated ¹⁷⁷Lu-PSMA-617 for patients who had received prior chemotherapy, this trial had a population of taxane-naive patients.

Dr Sartor stated ¹⁷⁷Lu-PSMA-617 "more than doubled the time to radiographic progression-free survival..." with an adverse event profile that was "very strong in favor of lutetium."

Transcript:

Hi, I'm Dr. Oliver Sartor. I'm at Mayo Clinic, but now I'm at ESMO. So, glad to be here at ESMO 2023 in Madrid. I have presented a presentation that I like a lot, and that is the PSMAfore pivotal phase 3 trial, comparing [¹⁷⁷Lu-PSMA-617] PSMA-lutetium to a hormonal therapy for those with metastatic castration-resistant prostate cancer.

Now this is important because these are chemotherapy naive patients, as opposed to the VISION trial, which was after the chemotherapy use. We had a positive trial. The primary endpoint was rPFS, radiographic progression-free survival, very strong data, top line 0.41 (little more mature analysis, 0.43) for the hazard ratio, more than doubled the time to radiographic progression-free survival. On the hormonal arm, it was about 5.6 months; on the lutetium arm, about 12 months. Tumors shrunk, we had more than a 50% overall response rate in terms of tumor shrinkage. We had PSA response rate 50% or better in more than 57% of the patients. We ended up with a crossover-adjusted overall survival benefit hazard ratio of 0.8. Confidence intervals did overlap once, so that's not statistically significant, but we said it trended the right way. Adverse event profile was very strong in favor of the lutetium. Yes, there was some dry mouth, but most of the patients had pretty mild adverse events as a whole.

I'll simply say overall we have a lot of positive endpoints that are hit. I forgot to mention things like health related quality of life, time to pain progression, all positive. I think this trial demonstrates patient benefit, and at this point it'll be up to the regulators as to what happens next. But at least we've done our duty with the trial. We've got a trial with a positive primary endpoint and crossover-adjusted hazard ratio trending in the right direction. Whole variety of secondary endpoints positive, good adverse event ratio. A pleasure to be able to present that here at ESMO 2023.

Source:

Sartor O, Castellano Gauna DE, Herrmann K, et al. Phase III trial of [¹⁷⁷Lu]Lu-PSMA-617 in taxane-naive patients with metastatic castration-resistant prostate cancer (PSMAfore). Presented at 2023 ESMO Annual Congress; October 20-24, 2023; Madrid, Spain. Abstract LBA13.