GlaxoSmithKline announces results from PRIMA
GlaxoSmithKline announced results from PRIMA, the Phase 3 randomised, double-blind, placebo-controlled study of Zejula as a maintenance therapy in women with first-line ovarian cancer following a response to platinum-based chemotherapy. Niraparib treatment resulted in a 38% reduction in the risk of disease progression or death in the overall population. These results were driven by a clinically meaningful reduction in risk of progression in women with: BRCA mutation tumours; HR-deficient BRCA wild type tumours; HR-proficient tumours. The PRIMA study enrolled patients with a response to their first-line treatment with platinum-based chemotherapy including those with high risk of disease progression, a population with high unmet need and previously under-represented in first-line ovarian cancer studies. In an interim analysis of overall survival, niraparib also demonstrated an encouraging trend toward improvement in OS relative to placebo. A pre-planned interim analysis of OS numerically favoured niraparib in the overall population. In the HR-deficient subgroup, 91% of women on niraparib were alive at 24 months vs. 85% for placebo. These data are not yet mature, and the significance is not fully known. The OS interim analysis also showed 81% of women receiving niraparib in the HR-proficient subgroup were alive at 24 months vs. 59% of women receiving placebo. Niraparib is not currently approved in the first-line ovarian cancer maintenance setting. GSK will share these data with the relevant health authorities and is on track to file by the end of the year. The safety profile demonstrated in PRIMA did not differ from the established safety profile. Validated patient reported outcomes indicate quality of life was similar between the niraparib and placebo treatment arms. Niraparib is marketed in the United States and Europe under the trade name Zejula.