29 Dose modification for Chinese patients on niraparib maintenance treatment for platinum-sensitive recurrent ovarian cancer: A post hoc analysis

Introduction/Background* In the NOVA trial of niraparib maintenance treatment (MT) in platinum-sensitive recurrent ovarian cancer (PSROC), dose reduction due to treatment-emergent adverse events (TEAEs) occurred in 66.5% of patients initiating niraparib at 300 mg. Based on NOVA RADAR analysis, subsequent individualised starting dose (ISD) recommends patients with baseline bodyweight Methodology In NORA, adults with PSROC and complete/partial response to most recent platinum-containing chemotherapy were randomised 2:1 to niraparib or placebo MT of 28-day cycles. Primary endpoint was progression-free survival (PFS). First 16 patients started treatment at 300 mg, before ISD was implemented. Dose interruption ≤28 days and dose reduction were permitted. Niraparib-treated patients with stabilised dosing at Cycle 4 were analysed, with descriptive statistics summarising TEAEs and descriptive PFS analysis by dose levels at the beginning of Cycle 4. Result(s)* During Month 1/2, platelet count decrease caused dose interruption and reduction in 32.8%/36.2% and 22.0%/23.6% of patients, respectively; neutrophil count decrease caused dose interruption and reduction in 9.0%/12.1% and 8.5%/9.2% of patients, respectively. These percentages decreased from Month 3 and remained low through Months 4–6 (figure 1). Anaemia-related dose interruption/reduction occurred in ≤10% of patients. Most patients’ stabilised doses at Cycle 4 were 100 mg (n=74) or 200 mg (n=78). These two groups had comparable baseline characteristics and showed similar PFS (figure 2) from Cycle 4 onward through 12 months, regardless of germline BRCA mutation status. Conclusion* Platelet count decrease and neutrophil count decrease were the major TEAEs necessitating niraparib dose modification. Early dose modification helped maintain safety and tolerability in Chinese patients receiving niraparib MT without compromising efficacy.