The phase 3 PSMAddition trial showed that adding Lutetium Lu 177 vipivotide tetraxetan to standard androgen-deprivation therapy (ADT) plus an androgen receptor pathway inhibitor (ARPI) significantly improved prostate-specific antigen (PSA) responses in patients with PSMA-positive metastatic hormone-sensitive prostate cancer (mHSPC).
The study included 1,144 patients, most with high tumor burden and bone metastases. Researchers previously reported that the trial met its primary endpoint of improved radiographic progression-free survival.
New findings showed the Pluvicto combination reduced the risk of PSA progression by 58% compared with ADT/ARPI alone. PSA progression events occurred in 8.7% of patients receiving Pluvicto versus 18.7% in the control arm.
The treatment also produced deeper PSA suppression. By week 48, 87.4% of patients in the Pluvicto arm achieved PSA levels below 0.2 ng/mL compared with 74.9% in the control group. Even more stringent PSA suppression below 0.02 ng/mL was achieved in 65.3% versus 46.7% of patients, respectively.
Although adverse events were more common with Pluvicto, investigators reported that the safety profile remained consistent with previous experience using the therapy.