1.Phase 2 single-arm study on the safety of maintenance niraparib in Japanese patients with platinum-sensitive relapsed ovarian cancer
Kazuhiro TAKEHARA ; Takashi MATSUMOTO ; Junzo HAMANISHI ; Kosei HASEGAWA ; Motoki MATSUURA ; Kiyonori MIURA ; Shoji NAGAO ; Hidekatsu NAKAI ; Naotake TANAKA ; Hideki TOKUNAGA ; Kimio USHIJIMA ; Hidemichi WATARI ; Yoshihito YOKOYAMA ; Yoichi KASE ; Shuuji SUMINO ; Ajit SURI ; Hiroaki ITAMOCHI ; Nobuhiro TAKESHIMA
Journal of Gynecologic Oncology 2021;32(2):e21-
Objective:
The primary objective of this study was to evaluate the safety of niraparib 300 mg/day in Japanese patients with platinum-sensitive, relapsed ovarian cancer in a maintenance setting.
Methods:
Phase 2, multicenter, open-label, single-arm study enrolled Japanese patients with platinum-sensitive, relapsed ovarian cancer who had received ≥2 platinum-based regimens.The primary endpoint (incidence of grade 3 or 4 thrombocytopenia-related events within 30 days after initial niraparib administration) was justified by the incidences of a global pivotal phase 3 study and its post-hoc safety analysis on thrombocytopenia, the major hematological adverse event of niraparib. The overall safety analysis examined other treatment-emergent adverse events (TEAEs).
Results:
Enrolled patients (n=19) had a median (min, max) body weight of 53.9 (40.8–79.1) kg; all but one patient weighed <77 kg. Most (94.7%) patients initially received niraparib 300 mg/day but this decreased in subsequent cycles (mean±standard deviation dose intensity, 191.6±65.7 mg/day). In total, 6/19 (31.6%) patients experienced grade 3 or 4 thrombocytopenia-related events within 30 days of initial niraparib administration.Other common TEAEs included nausea, and decreased platelet or neutrophil counts. No progression-free or overall survival events occurred; only 1 of 4 response-evaluable patients had a post-baseline tumor assessment (stable disease).
Conclusion
The incidence of grade 3 or 4 thrombocytopenia-related events in Japanese ovarian cancer patients was similar to that in the corresponding non-Japanese study. Overall, the safety profile was acceptable and consistent with the known safety profile and previous experience with niraparib.