US pharmaceutical company Merck & Co Inc (NYSE:MRK), known as MSD outside the US and Canada, announced on Thursday that it has discontinued two Phase 3 clinical trials, KEYNOTE-867 and KEYNOTE-630, based on independent Data Monitoring Committee (DMC) recommendations.

KEYNOTE-867 evaluated KEYTRUDA (pembrolizumab) in combination with stereotactic body radiotherapy (SBRT) for stage I or II non-small cell lung cancer (NSCLC). The DMC recommended discontinuation due to a lack of improvement in event-free survival (EFS) or overall survival (OS) compared to placebo plus SBRT. Additionally, KEYTRUDA in combination with SBRT was associated with higher rates of adverse events (AEs), including AEs leading to death, compared with SBRT and placebo.

KEYNOTE-630 evaluated KEYTRUDA for the adjuvant treatment of high-risk locally advanced cutaneous squamous cell carcinoma (cSCC) following surgery and radiation. The DMC recommended discontinuation due to a lack of statistical significance in recurrence-free survival (RFS). OS was not formally tested, but at the time of the analysis the results did not favour KEYTRUDA compared to placebo. The safety profile of KEYTRUDA in this trial was consistent with its established safety profile.

Merck has informed study investigators and advised patients to discuss next steps with their physicians. Data analyses for both trials are ongoing and will be shared with the scientific community and regulatory agencies.