Article Text
Abstract
Introduction/Background Niraparib, a poly(ADP-ribose) polymerase inhibitor (PARPi), was approved in the EU in 2017 as maintenance treatment for platinum-sensitive recurrent (2LM+) ovarian cancer (OC) and in 2020 as first-line maintenance (1LM) following first-line platinum-based chemotherapy. Interim results from a prospective, noninterventional, single-arm, regulatory study characterising the risk of developing myelodysplastic syndrome/acute myeloid leukaemia (MDS/AML) and other secondary primary malignancies (SPMs) of patients treated with niraparib in routine clinical practice are presented.
Methodology Adult patients diagnosed with epithelial OC from Germany, Italy, Netherlands, and Spain who received niraparib maintenance treatment were enroled. Patients were followed from niraparib initiation (index date) to the earliest of study completion at 5 years’ follow-up, study discontinuation, death, or data cutoff (10Feb2023). MDS/AML, other SPMs, and treatment-emergent adverse events (TEAEs) incidence were summarised. Analyses were stratified by niraparib use in 1LM or 2LM+ setting.
Results As of 10Feb2023, 740 patients (174 1LM; 566 2LM+) were enroled and met analytic cohort criteria (median age, 65 years; 90% stage III/IV high-grade serous OC at diagnosis; 14.4% BRCA-mutated. Follow-up was ongoing for 62.7% of patients. Median (Q1, Q3) duration of niraparib treatment was 6.6 (3.3, 11.5) and 9.3 (4.1, 20.5) months in 1LM and 2LM+ cohorts, respectively, reflecting the study’s ongoing nature. A total of 8 patients (1.1%) experienced 10 MDS/AML events, and 4 patients (0.5%) experienced a total of 5 SPMs (table 1). All events occurred in the 2LM+ cohort. Overall, 44.1% (n=326) of patients experienced at least 1 TEAE, 15.4% (n=114) had a grade ≥3 TEAE, and 7.4% (n=55) experienced a serious TEAE.
Conclusion The regulatory interim analysis results are consistent with niraparib’s known safety profile. For all safety outcomes, including MDS/AML and other SPMs, observed event rates were lower than those reported in niraparib clinical trials and label. No new safety signals were observed.
Disclosures This study (OneCDP213705) was sponsored by GSK (Waltham, MA, USA). Syneos Health received consulting fees to conduct this study.