Patient-reported outcomes of maintenance rucaparib in patients with recurrent ovarian carcinoma in ARIEL3, a phase III, randomized, placebo-controlled trial

Purpose: To compare NFOSI-18 Disease Related Symptoms - Physical (DRSP), Total score, and side effect bother between maintenance rucaparib (600 mg twice daily) vs. placebo in the phase III ARIEL3 trial.

Methods: ARIEL3 (NCT01968213) included patients with ovarian carcinoma who responded to second-line or later platinum-based chemotherapy. The NFOSI-18 DRS-P and Total scales were secondary endpoints. The NFOSI-18 contains a side effect impact item (GP5): "I am bothered by side effects of treatment." We compared treatment arms on change from baseline of DRS-P and Total scores using mixed models with repeated measures (MRMM). Time to first and confirmed deterioration of NFOSI-18 DRS-P and Total scales were analyzed using Cox regression. We also calculated the proportion of patients reporting moderate to high side effect bother on GP5.

Results: In the intention-to-treat (ITT) cohort, mean change from baseline favored the placebo. Compared to placebo, rucaparib was associated with higher risk of deterioration [e.g., 4-point deteriorator definition hazard ratio (HR): 1.85; 95% CI: 1.46, 2.36; median time to first deterioration on DRSP: 1.9 vs. 7.0 months]. Confirmed deterioration results resembled those for first deterioration. Proportions of patients reporting moderate/high side effect bother on GP5 fluctuated around 20% across treatment cycles. Results in BRCA mutant and homologous recombination deficient cohorts were generally similar to those from the ITT cohort.

Conclusion: This placebo-controlled study in the maintenance therapy setting provides a unique view of the impact of PARP inhibition on the patient-reported outcomes that are commonly used in ovarian cancer clinical trials. Information regarding the adverse side effect impact of PARP inhibitors should be weighed against their clinical benefit.