GSK halts MAGRITi Phase III trial

GlaxoSmithKline (GSK) has announced that it is to stop its MAGRITi trial, a Phase III trial of its MAGE-A3ii cancer immunotherapeuticiii in non-small cell lung cancer (NSCLC) patients.

The decision was taken after establishing that it will not be possible to identify a sub-population of gene-signature positive NSCLC patients that may benefit from the treatment.

Data from the trial announced recently showed that it did not meet its first or second co-primary endpoints as it did not significantly extend disease-free survival (DFSiv) when compared to placebo in either the overall MAGE-A3 positive population (first co-primary endpoint) or in those MAGE-A3-positive patients who did not receive chemotherapy (second co-primary endpoint).

GSK continued with the MAGRIT trial to investigate the third co-primary endpoint of DFS in a gene signature positive sub-population, which was designed to identify a subset of MAGE-A3 positive patients that may benefit from the treatment. However, the pre-planned independent third-party analysis of a proportion of the data (to identify a gene signature classifier) has concluded that assessment of the third co-primary endpoint is not feasible due to an insufficient treatment effect.

GSK will now gain access to the un-blinded data, in order to conduct a full assessment of the findings and understand learnings for other aspects of immunotherapy development within GSK.

The Independent Data Monitoring Committee (IDMC) indicated that its review of the current safety information revealed no specific safety concern and the data is in line with the known safety information for the MAGE-A3 cancer immunotherapeutic.