Niraparib Associated With Longer PFS in Newly Diagnosed Ovarian Cancer

Barcelona, Spain—Niraparib is associated with significantly longer progression-free survival (PFS) than placebo among patients with newly diagnosed advanced ovarian cancer, according to results from the phase 3 PRIMA study.

These results were presented by Antonio Gonzalez-Martin, MD, co-director, department of medical oncology, Clinica Universidad de Navarra, Spain, at the ESMO 2019 Congress.

PRIMA randomized patients with newly diagnosed advanced ovarian cancer in a 2:1 ratio to receive niraparib or placebo once daily after a response to platinum-based chemotherapy.

The primary end point was PFS in patients whose tumors had homologous-recombination deficiency as well as PFS in the overall population. A prespecified interim analysis for overall survival (OS) was conducted at the time of the primary analysis for PFS.

A total of 733 patients underwent randomization. Of these patients, 373 (50.9%) had homologous-recombination deficient tumors.

The median PFS among patients with homologous-recombination deficient tumors was significantly longer in those who received niraparib than those who received placebo (21.9 months vs 10.4 months; HR, 0.43; 95% confidence interval [CI], 0.31-0.59; P<0.001).

In the overall population, the median PFS was 13.8 months with niraparib compared with 8.2 months with placebo (HR, 0.62; 95% CI, 0.50-0.76; P<0.001)

The rate of OS at the 24-month interim analysis was 84% in the niraparib group compared with 77% in the placebo group (JR, 0.70; 95% CI, 0.44-1.11). 

The most common adverse events grade ≥3, occurring in 31% of patients, were thrombocytopenia (in 28.7%), and neutropenia (in 12.8%). No treatment-related deaths were reported.

“Among patients with newly diagnosed advanced ovarian cancer who had a response to platinum-based chemotherapy, those who received niraparib had significantly longer progression-free survival than those who received placebo, regardless of the presence or absence of homologous-recombination deficiency,” Dr Gonzalez-Martin and colleagues reported.

“Based on these results, niraparib monotherapy after first-line platinum-based chemotherapy should be considered a new standard of care,” Dr Gonzalez-Martin concluded during his presentation.—Janelle Bradley

González-Martín A, Pothuri B, et al. Niraparib therapy in patients with newly diagnosed advanced ovarian cancer (PRIMA/ENGOT-OV26/GOG-3012 study). Presented at: ESMO 2019 Congress; September 27-October 1, 2019; Barcelona, Spain. Abstract LBA1.