Survival outcomes for ovarian cancer patients in the post–poly ADP-ribose polymerase inhibitor (PARPi) era in the US.

5586 Background: PARPi introduction in clinical practice has led to major changes in the therapeutic landscape for ovarian cancer (OC) 1 . Olaparib is approved alone or in combination with bevacizumab for the first line maintenance therapy of BRCA-mutated or homologous repair deficient (HRD) OC. We hypothesize that the introduction of PARPi in routine clinical practice for maintenance therapy in OC has resulted in improvements in survival outcomes among OC patients (pts) treated in the real world. Methods: Pts with a diagnosis of stage III/IV epithelial OC age ≥18 years between 2000-2021 were obtained from the Surveillance, Epidemiology, and End Results (SEER) Database. A cutoff on 2017 was made based on the initial approval of PARPi for maintenance therapy. Statistical analyses were conducted with SPSS. Pts characteristics were reported in frequencies and compared with the Chi-squared test. The Kaplan-Meier method was used to estimate median OS. Cox Regression was used identify independent prognostic factors of survival. P-value ≤0.05 was considered statistically significant. Results: 59,913 pts were included with median age 63 years, 60.9% non-hispanic white, and 55.8% with serous histology. 44,873 pts were diagnosed in the pre-PARPi cohort and 15,040 in the post-PARPi cohort. 76.3% and 76.1% of pts received any chemotherapy and surgery, respectively. Similar distribution in analyzed variables was found when comparing among eras. The median OS for pre-PARPi pts was 37 months (95%CI: 36.4-37.6) and post-PARPi pts was 38 months (36.6-39.4), p=0.023. In multivariate analysis, pts diagnosed in the post-PARPi era had improved OS compared with pts in pre-PARPi era (HR=0.93, 95%CI:0.91-0.96, p<0.001). Conclusions: To the extent of our knowledge, this study is the first real world analysis of survival outcomes in OC pts after the introduction of PARPi at a population level in the US. The introduction of PARPi maintenance therapy has resulted in a modest improvement in OS in the overall OC population unselected for BRCA or HRD status. 1. Tew WP et al. J Clin Oncol. 2020 Oct 20;38(30):3468-93.