GSK reports Phase III RUBY trial of Jemperli plus chemo meets OS endpoint

GSK plc announced positive headline results from a planned analysis of Part 1 of the RUBY/ENGOT-EN6/GOG3031/NSGO phase III trial investigating Jemperli plus standard-of-care chemotherapy, followed by dostarlimab as a single agent, compared to placebo plus chemotherapy followed by placebo in adult patients with primary advanced or recurrent endometrial cancer. The trial met its primary endpoint of overall survival, or OS, demonstrating a statistically significant and clinically meaningful benefit in the overall patient population. A clinically meaningful OS benefit was observed in both prespecified subpopulations in the trial: mismatch repair deficient/microsatellite instability-high and mismatch repair proficient/microsatellite stable patient subgroups. OS is one of two primary endpoints in the RUBY Part 1 trial. Previously, the trial met its other primary endpoint of progression-free survival, or PFS, demonstrating a 72% and 36% reduction in the risk of disease progression or death observed in the dMMR/MSI-H population and overall patient population, respectively. Hesham Abdullah, Senior Vice President, Global Head Oncology, R&D, GSK, said: “With today’s headline results from Part 1 of the phase III RUBY trial, dostarlimab plus chemotherapy has become the only immuno-therapy combination to show a survival benefit in this broader patient population in this treatment setting. We look forward to sharing detailed results of this analysis with regulatory authorities and the larger scientific community.” Full results from this latest analysis from the trial will be published in a medical journal and presented at an upcoming scientific meeting. The safety and tolerability profile of dostarlimab plus carboplatin and paclitaxel was generally consistent with the known safety profiles of the individual agents.