Research in context
Evidence before this study
We searched PubMed using the search terms “poly (ADP-ribose) polymerase inhibitor” or “PARP inhibitor”, “ovarian cancer”, “maintenance”, and “platinum-sensitive relapsed”, using no date or language restrictions. The phase 2 Study 19 trial showed an apparent overall survival benefit with maintenance olaparib capsules versus placebo in the subgroup of patients with platinum-sensitive relapsed ovarian cancer and a BRCA1/2 mutation.
Added value of this study
To our knowledge, olaparib is the only poly (ADP-ribose) polymerase (PARP) inhibitor with long-term follow-up data and SOLO2 is the first phase 3 trial that provides final overall survival data on maintenance therapy with a PARP inhibitor (olaparib) in patients with platinum-sensitive, relapsed ovarian cancer and a BRCA1/2 mutation. Improvements in overall survival are difficult to demonstrate in ovarian cancer trials because of crossover and use of post-progression therapies. However, this analysis showed an overall survival improvement of 12·9 months with maintenance olaparib compared with placebo, although this finding was not statistically significant.
Implications of all the available evidence
Patients with relapsed ovarian cancer are a challenging population to treat, and usually receive multiple lines of chemotherapy, with time to relapse typically shortening with each successive line of treatment. Prior to this analysis, little progress had been made in demonstrating overall survival improvements in ovarian cancer since the introduction of platinum-based chemotherapy. The final analysis of SOLO2 shows a clinically meaningful overall survival benefit of maintenance olaparib for patients with platinum-sensitive relapsed ovarian cancer and a BRCA1/2 mutation, although the predefined threshold for statistical significance was not met.