Positive Phase III data on GSK's Jemperli in endometrial cancer

A late comer to the PD-/PD-Li inhibitors sector, UK pharma major GSK (LSE: GSK) has had a fair number of disappointments with its new cancer drugs. Just a few days ago, the company withdrew the US marketing authorization for multiple myeloma drug Blenrep (belantamab mafodotin-blmf). GSK also said it is restricting the US indication for Zejula in the second-line maintenance setting to only the gBRCAmut patient population.

However, today GSK announced positive headline results from the planned interim analysis of Part 1 of the RUBY/ENGOT-EN6/GOG3031/NSGO Phase III trial investigating Jemperli (dostarlimab) plus standard-of-care chemotherapy (carboplatin-paclitaxel) followed by Jemperli compared to chemotherapy plus placebo followed by placebo in adult patients with primary advanced or recurrent endometrial cancer, that met its primary endpoint of investigator-assessed progression-free survival (PFS).

The study showed a statistically-significant and clinically-meaningful benefit in the prespecified mismatch repair deficient (dMMR)/microsatellite instability-high (MSI-H) patient subgroup and in the overall population. A clinically relevant benefit in PFS was also observed in the mismatch repair proficient (MMRp)/microsatellite stable (MSS) patient subgroup.