Niraparib improves PFS in Chinese patients with ovarian cancer

An individualized dosing regimen of niraparib, a potent inhibitor of PARP 1/2, resulted in significantly improved progression-free survival (PFS) among Chinese patients with platinum-sensitive recurrent (PSR) ovarian cancer, according to a subgroup analysis of the NORA* study presented at ESMO Asia 2020.

This analysis involved 249 patients with PSR ovarian cancer (median age 54 years) who received an individualized starting dose (ISD) of niraparib 200 mg once/day (n=166; baseline body weight <77 kg and platelet count <150,000/µL) or placebo (n=83). [ESMO Asia 2020, abstract 2350]

As assessed by BICR**, patients who received niraparib had a significantly longer PFS than those who received placebo (median 18.3 vs 5.4 months; hazard ratio [HR], 0.30; p<0.0001).

The significant PFS benefit with niraparib vs placebo was evident regardless of germline BRCA (gBRCA) mutation status (gBRCA: median not reached vs 5.5 months; non-gBRCA: median 11.1 vs 3.8 months; HRs, 0.18 and 0.39, respectively; p<0.0001 for both subgroups).

“[Overall, this] prespecified analysis revealed that the PFS benefit of niraparib was consistent among all patient subgroups,” said lead author Dr Jianqing Zhu from the Department of Gynecologic Oncology at Fudan University Shanghai Cancer Center in Shanghai, China.

Patients on niraparib also experienced a significantly longer chemo-free interval (median 19.4 vs 9.7 months; HR, 0.33; p<0.0001) and time-to-first subsequent therapy (median 16.7 vs 7.7 months; HR, 0.35; p<0.0001) than those on placebo.

Overall survival data was still immature at data cut-off.

Grade ≥3 haematological treatment-emergent adverse events (TEAEs) more commonly reported in the niraparib vs the placebo group were decreased neutrophil count (20.5 percent vs 8.4 percent), anaemia (13.9 percent vs 2.4 percent), decreased platelet count (9.6 percent vs 1.2 percent), and decreased white blood cell count (7.2 percent vs 2.4 percent).

Overall, any TEAEs leading to treatment discontinuation occurred at a lower rate in the niraparib vs the placebo group (4.2 percent vs 6.0 percent). Most of the AEs were manageable with dose modification, Zhu noted.

“This is the first randomized clinical trial to demonstrate the efficacy and safety of niraparib in Chinese patients with PSR ovarian cancer,” said Zhu. “[Niraparib] should be considered [the] standard clinical practice in this patient population, especially in Asian patients with low body weight,” he suggested.

“[The results were] consistent with the [NORA] intention-to-treat population … [in demonstrating] significant PFS benefit,” he added.

*NORA: Clinical trial evaluating the efficacy and safety of ZL-2306 (niraparib) in ovarian cancer patient

**BICR: Blinded-independent central review