ASCO 2026 data reveal the PARP inhibitor talazoparib, combined with enzalutamide, significantly delays disease progression in men with HRR-deficient metastatic castration-sensitive prostate cancer.
The Phase 3 TALAPRO-3 trial randomized 599 patients to receive either the combination or placebo plus enzalutamide. All patients had homologous recombination repair gene alterations.
At a median follow-up of about 37.7 months, the combination therapy improved radiographic progression-free survival. Median rPFS was not reached in the talazoparib arm versus 45.8 months with standard therapy. The hazard ratio was 0.481.
The strongest benefit was observed in patients with BRCA-mutated disease, where the hazard ratio was 0.368.
Interim overall survival data favored the combination, but statistical significance was not yet reached. There were 74 deaths in the talazoparib group versus 91 in the placebo group.
Anemia and fatigue were the most common side effects. No new safety signals were identified.
Researchers say the findings support talazoparib plus enzalutamide as a clinically meaningful strategy for this patient population.