Progression-free survival by investigator versus blinded independent central review in newly diagnosed patients with high-grade serous ovarian cancer: Analysis of the VELIA/GOG-3005 trial.

OBJECTIVE

In the phase 3 VELIA/GOG-3005 trial, veliparib added to carboplatin-paclitaxel and continued as maintenance improved progression-free survival (PFS) compared to carboplatin-paclitaxel alone in patients with newly diagnosed ovarian carcinoma. Primary analysis of PFS was by investigator (INV) assessment, with a supplemental analysis of PFS by blinded independent central review (BICR).

METHODS

Patients received veliparib or placebo with carboplatin-paclitaxel (6 cycles) and as maintenance (30 additional cycles). The primary analysis compared PFS in the veliparib-throughout arm to the carboplatin-paclitaxel only arm in the BRCA mutation (BRCAm), homologous recombination deficiency (HRD), and intention-to-treat (ITT) populations. Exploratory analyses of PFS in BRCA wildtype (BRCAwt), homologous recombination proficient (HRP), and HRD + BRCAwt populations were also performed. PFS per BICR and overall concordance rates between INV and BICR assessments were analyzed.

RESULTS

Hazard ratios for PFS by INV and BICR were consistent in each of the primary analysis and exploratory populations. In the ITT population, median PFS per INV was 23.5 months in the veliparib-throughout arm versus 17.3 months in the control arm (hazard ratio [HR] 0.683, 95% confidence interval [CI] 0.562-0.831; P < 0.001). Median PFS by BICR was 29.3 months versus 19.2 months (HR 0.687, 95% CI 0.504-0.806). In the ITT population, the overall concordance rates between INV and BICR were 78% and 75% for the veliparib-throughout and control arms, respectively.

CONCLUSIONS

Hazard ratios for PFS per BICR and per INV were consistent, with no suggestion of investigator bias. These findings support the reliability of PFS by INV in ovarian cancer trials.