Phase 3 PSMAddition: adding [177Lu]Lu-PSMA-617 to hormone therapy extends radiographic progression-free survival in PSMA-positive metastatic prostate cancer (HR 0.72)

In the phase 3 PSMAddition trial (1144 patients, 572 per arm), adding the radioligand [177Lu]Lu-PSMA-617 to androgen deprivation therapy plus an androgen-receptor pathway inhibitor prolonged radiographic progression-free survival: HR 0.72 (95% CI 0.58-0.90; p=0.0021), a 28% relative reduction in the risk of radiographic progression or death, with median not reached in either arm. Progression or death occurred in 139 patients (24%) on the radioligand versus 172 (30%) on control. The benefit carries a cost: grade 3 or worse adverse events occurred in 286 of 564 patients (51%) versus 243 of 565 (43%), and dry mouth in 46% versus 4%. The trial enrolled patients naive or sensitive to androgen pathway modulators, and at this stage it does not demonstrate an overall survival benefit.