Parameters for Dose Reduction in Niraparib Therapy for Ovarian Cancer
Posted: Monday, August 6, 2018
Patients receiving niraparib for treatment of recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer who have a lower body weight or decreased platelet count may benefit from a reduced starting dose (200 mg/day), according to a retrospective analysis of the ENGOT-OV16/NOVA trial that identified clinical parameters to predict dose reductions. J. S. Berek, MD, MMS, of Stanford Women’s Cancer Center, Stanford, California, and colleagues published their findings in the Annals of Oncology.
Dr. Berek and colleagues found that patients with a baseline body weight of < 77 kg or baseline platelet count of < 150,000/µL experienced a reduction in adverse events, particularly grade ≥ 3 thrombocytopenia, when niraparib was initiated at 200 mg daily versus the standard 300-mg daily dose.
“The effectiveness of the dose modification strategy was demonstrated by the relatively few patients who discontinued [therapy] due to these events,” stated the research team. This dosing regimen is now being used in ongoing clinical trials of niraparib monotherapy, they added.
Overall, 80% of patients treated with niraparib experienced dose interruptions for any reason in the ENGOT-OV16/NOVA trial, with 73% having a dose reduction. As a result of dose interruptions and reductions, the average daily dose in the first 2 months for patients with either a body weight < 77 kg or a baseline platelet count < 150,000/µL was 207 mg.
Additionally, investigators found that progression-free survival in patients who had dose reductions to either 200 mg or 100 mg was consistent with that of patients who remained at the 300-mg starting dose.