Real-World First-Line Maintenance Niraparib Monotherapy Use Following Chemotherapy Plus Bevacizumab: The SW1TCH Study

Clinical trials have demonstrated prolonged survival associated with niraparib first-line maintenance (1LM) therapy, compared with placebo, for patients with ovarian cancer (OC). However, data are limited on real-world 1LM niraparib monotherapy use, particularly as switch 1LM, following first-line (1L) combination chemotherapy plus bevacizumab. This real-world study aimed to describe patient demographics, clinical characteristics, and clinical outcomes of patients with OC receiving 1LM niraparib monotherapy following 1L combination chemotherapy plus bevacizumab.

This retrospective observational study used data from a US-based nationwide database of deidentified, electronic health record-derived data. Patients diagnosed with OC during the study period (1 January 2011-30 November 2022, inclusive) were eligible if they received 1L chemotherapy plus bevacizumab treatment followed by 1LM niraparib monotherapy, initiated between 1 January 2017 (inclusive) and 2 September 2022. Patients were followed from index date (initiation of niraparib 1LM) until the first occurrence of death, end of follow-up, or end of study. Clinical outcomes were time to treatment discontinuation (TTD) and time to next treatment (TTNT). Kaplan-Meier curves were used to estimate TTD, TTNT, and 95% confidence intervals (CIs).

Among 93 patients selected, median age at index was 67 years (interquartile range [IQR] 60-72 years). Most patients had BRCA wild-type/homologous recombination (HR)-proficient or BRCA wild-type/HR unknown disease (75.3%). In all, 18 (19.4%) patients had HR-deficient disease. Five (5.4%) patients had unknown test results for both BRCA and HR deficiency status. Median follow-up time was 16.3 months (IQR 8.7-25.4 months), and median time from end of 1L therapy to 1LM initiation was 35.0 days (IQR 25.0-53.9 days). Median TTD was 9.3 months (95% CI 6.1-11.3 months). Median TTNT was 12.9 months (95% CI 11.5-19.0 months).

This real-world study provided insights into switch maintenance with 1LM niraparib monotherapy, which may be a viable treatment option for patients with advanced OC.