PCN532 WOMEN'S PREFERENCES ON BENEFITS, RISKS, AND SIDE EFFECTS OF MAINTENANCE PARP INHIBITOR THERAPY IN OVARIAN CANCER

More women with ovarian cancer in remission are receiving maintenance therapy with PARP inhibitors. But, it is unclear whether women are willing to accept side effects and risks associated with maintenance therapy for extended progression-free survival (PFS) or overall survival (OS). We designed a discrete-choice experiment to elicit the preferences of women with ovarian cancer regarding tradeoffs among 6 attributes relevant to the decision for maintenance PARP inhibitor therapy versus surveillance: (1) OS (36, 38, 42 months); (2) PFS (15, 17, 21 months); (3) nausea (none, mild, moderate); (4) fatigue (none, mild, moderate); (5) probability of death from myelodysplastic syndrome/acute myelogenous leukemia (MDS/AML) (0%, 1%, 5%, 10%); and (6) monthly out-of-pocket cost ($0, $50, $500, $1,000). Choice questions represented 2 maintenance scenarios and an opt-out scenario representing a treatment break. We analyzed choice data using random-parameters logit regression. Of 150 women with ovarian cancer recruited, 95 were eligible and completed the survey. Mean age was 62, 48% had recurrent ovarian cancer, and 13% were currently taking a PARP inhibitor. Preference weights were logically ordered, with better clinical outcomes significantly preferred to worse (except between 0% and 1% risk of MDS/AML) and lower costs preferred to higher. On average, participants would tolerate a 2% (95%CI: -1, 5) additional risk of MDS/AML in exchange for 2 additional months of PFS and 7% (4, 10) additional risk of MDS/AML in exchange for 6 additional months of PFS. Risk tolerance was greater for gains in OS, accepting a 6% (2, 8) additional risk of MDS/AML for a 2-month gain in OS and a 13% (10, 20) additional risk for a 6-month OS gain. To realize clinically observed levels of improvement in PFS with maintenance PARPi therapy, women with ovarian cancer are willing to accept a risk of MDS/AML that surpasses clinically observed risk levels.