As reported in the Journal of Clinical Oncology by Scambia et al, the final overall survival results of the phase III SOLO3 trial showed similar outcomes with olaparib vs non–platinum-based chemotherapy in patients with platinum-sensitive BRCA-mutated relapsed ovarian cancer.
In the initial report from the trial, olaparib significantly improved objective response rate vs chemotherapy (odds ratio = 2.53, 95% confidence interval [CI] = 1.40–4.58, P = .002), with a significant progression-free survival benefit being observed (hazard ratio [HR] = 0.62, 95% CI = 0.43–0.91, P = .01).
Study Details
In the open-label trial, 266 patients from sites in 13 countries were randomly assigned 2:1 to olaparib (n = 178) or physician’s choice of single-agent non–platinum-based chemotherapy (pegylated liposomal doxorubicin, paclitaxel, gemcitabine, or topotecan; n = 88).
Key Findings
The median overall survival was 34.9 months (95% CI = 30.0–39.2 months) in the olaparib group vs 32.9 months (95% CI = 23.5–43.2 months) in the chemotherapy group (HR = 1.07, 95% CI = 0.76–1.49, P = .71). Rates at 24 and 48 months were 68% vs 62% and 34% vs 34%.
The hazard ratio for overall survival favored olaparib in 88 vs 46 patients with two previous chemotherapy lines of treatment (median = 37.9 vs 28.8 months; HR = 0.83, 95% CI = 0.51–1.38), but favored chemotherapy among 90 vs 42 patients who had received at least three previous chemotherapy lines (median = 29.9 vs 39.4 months, HR = 1.33, 95% CI = 0.84–2.18). As noted by the investigators, BRCA reversion mutations might have contributed to this finding. None of the six patients (3.5%) in the olaparib group with a BRCA reversion mutation detected at baseline achieved an objective tumor response.
The investigators concluded: “At final SOLO3 analysis, [overall survival] was similar with olaparib and chemotherapy and might have been affected by several factors.”
Giovanni Scambia, MD, of the Università Cattolica del Sacro Cuore-Fondazione Policlinico A. Gemelli, IRCCS, Rome, is the corresponding author for the Journal of Clinical Oncology article.
Disclosures: The study was funded by AstraZeneca and is part of an alliance between AstraZeneca and Merck Sharp & Dohme LLC, a subsidiary of Merck & Co, Inc. For full disclosures of all study authors, visit the Journal of Clinical Oncology.
