The phase 3 TALAPRO-2 trial found that radiographic progression-free survival (rPFS) strongly correlates with overall survival (OS) in first-line metastatic castration-resistant prostate cancer (mCRPC) treated with talazoparib plus enzalutamide.
The study analyzed 805 patients in the overall population, 399 with homologous recombination repair (HRR) gene mutations, and 155 with BRCA1/2 alterations. Researchers reported moderate-to-strong correlations between rPFS and OS across nearly all groups. The strongest association was seen in the unselected cohort, with a Spearman correlation coefficient of 0.812. Strong correlations were also observed in HRR-deficient and BRCA-mutated patients.
Results were consistent whether progression was assessed centrally or locally. Researchers said validating rPFS as a surrogate for OS could shorten clinical trial timelines and accelerate regulatory approvals, helping patients gain faster access to new therapies.