Oaknin A, Oza AM, Lorusso D, et al. - Among patients with advanced ovarian cancer in ARIEL3, rucaparib maintenance treatment was evaluated with respect to its efficacy and safety in subgroups based on best response to most recent platinum-based chemotherapy and baseline disease.

• Either oral rucaparib at a dosage of 600 mg twice daily or placebo was administered to participants.

• Following prespecified, nested cohorts were examined for investigator-assessed PFS: BRCA-mutated, homologous recombination deficient (HRD; BRCA mutated or wild-type BRCA/high loss of heterozygosity), and the intent-to-treat (ITT) population.

• Safety profiles appeared similar between subgroups.

• Significantly longer median PFS (investigator-assessed) was recorded with rucaparib maintenance treatment (10.8 months) vs placebo (5.4 months; HR, 0.36) in the ARIEL3 overall ITT population.

• Among patients in the ITT populations of each subgroup analysis, there was reduction in the risk of disease progression that was consistent with that of the overall ARIEL3 ITT population.

• Similarly, the lowered risk of progression within subgroups in the nested BRCA-mutated and HRD cohorts within each subgroup analysis, was consistent with that of the respective cohorts in the overall ARIEL3 study.

• Overall, rucaparib maintenance treatment is linked with achievement of clinically meaningful efficacy benefits across subgroups based on response to last platinum-based chemotherapy or baseline disease.