Niraparib Rechallenge After Surgery in Ovarian Cancer Patients With Oligometastatic Progression

This is a single-arm phase II clinical trial which will enroll female patients aged ≥ 18 years with high grade serous or endometrioid ovarian cancer (OC) who have had an oligometastatic progression (OMP) during or after the first maintenance therapy with any poly adenosine diphosphate (ADP) ribose polymerase inhibitor (PARPi). OMP is defined as 1-5 metastatic lesions. Patients with systemic metastatic disease are not eligible. A total of 30 patients with OC and OMP will be enrolled and will receive treatment with niraparib 300 or 200 mg, according to body weight or platelet count. Patients will start treatment within 8 weeks after surgery and will receive it until progressive disease or treatment discontinuation. The main objective of the study is to evaluate progression-free survival (PFS) of niraparib rechallenge in OC patients with OMP and no residual disease after secondary cytoreductive surgery. Main secondary objectives are to assess the PFS according to biomarker status (BRCAm, BRCAwt, HRD and HRP), the PFS by CA 125, the time to start of first subsequent therapy or death (TFST) and the overall survival (OS).