US pharmaceutical company Merck & Co Inc (NYSE:MRK), known as MSD outside the US and Canada, reported on Thursday that it has initiated a Phase 3 clinical trial for MK-1084, an investigational oral selective KRAS G12C inhibitor, in combination with KEYTRUDA (pembrolizumab) for first-line treatment of certain patients with metastatic non-small cell lung cancer (NSCLC) whose tumours harbour KRAS G12C mutations and express PD-L1.

Dr Marjorie Green, Merck's senior vice president of oncology, noted that KRAS is among the most prevalent mutations in cancer and KRAS G12C is the most common KRAS mutation in patients with NSCLC.

Early evidence showed promising anti-tumour activity and manageable safety profile for MK-1084 with KEYTRUDA, prompting the move to a Phase 3 trial.

Planned to enrol approximately 600 patients globally, the trial aims to assess progression-free survival, overall survival, objective response rate and duration of response.

MK-1084 is being developed through a collaboration with Taiho Pharmaceutical Co Ltd and Astex Pharmaceuticals (UK), a subsidiary of Otsuka Pharmaceutical Co Ltd.