Poly(ADP-ribose) polymerase inhibitor maintenance therapy in ovarian cancer: a single-center retrospective study

To determine the effectiveness and tolerability of PARPi maintenance in a real-world patient population. Specifically, to assess duration of PARPi, the rate of secondary malignancies, rate of side effects, and survival.

A retrospective review of patients with ovarian, fallopian tube, and primary peritoneal cancer at OhioHealth Riverside Methodist Hospital in Columbus, Ohio was performed. All patients diagnosed since March 2015 were reviewed for eligibility. Data was collected via EMR query and stored in REDCap. Charts were reviewed for multiple data points, including duration of PARPi use, side effects, secondary malignancies, survival, and recurrence. Data were reported descriptively with medians and ranges.

Ninety-seven patients met inclusion criteria. The median time patients were maintained on a PARPi was 9.8 months. Termination of patient's PARPi was most often due to recurrence followed by side effects. Fatigue, anemia, and thrombocytopenia were the most common side effects reported. We report a PFS median of 12.5 months and a median OS of 40.6 months following first PARPi exposure. When stratified by homologous recombination deficiency (HRD) status, unadjusted analyses demonstrated longer PFS among HRD-positive patients compared to HRD-negative and HRD-unknown groups; however, this association was not consistently maintained after multivariable adjustment, and no statistically significant difference in OS was observed. There were two secondary malignancies identified in our study.

We report similar survival compared to published trials despite shorter courses of therapy and higher rates of discontinuation due to side effects. Although HRD-positive status was associated with improved outcomes in unadjusted analyses, this effect was not sustained after adjustment for confounding variables, underscoring the complexity of these associations in real-world populations. This cohort study emphasizes the need to examine the real-world population for accurate patient guidance and counseling.