Pharmaceutical giant Merck & Co Inc has announced the discontinuation of two Phase 3 clinical trials evaluating its blockbuster immunotherapy drug, Keytruda (pembrolizumab). The decision was made based on recommendations from independent Data Monitoring Committees (DMCs), which reviewed interim data from the trials.
The first trial, KEYNOTE-867, investigated the use of Keytruda in combination with stereotactic body radiotherapy (SBRT) for the treatment of stage I or II non-small cell lung cancer (NSCLC). The DMC recommended stopping the trial due to a lack of improvement in event-free survival or overall survival, the study’s primary and key secondary endpoints, respectively. Furthermore, the combination therapy was associated with higher rates of adverse events, including those leading to death, compared to SBRT and placebo.
The second trial, KEYNOTE-630, evaluated Keytruda as an adjuvant treatment for patients with high-risk locally advanced cutaneous squamous cell carcinoma (cSCC) following surgery and radiation. The DMC recommended halting the trial for futility, as the risk/benefit profile did not support its continuation. The interim analysis revealed that Keytruda did not meet the statistical significance threshold for recurrence-free survival, the primary endpoint. While the study’s key secondary endpoint, overall survival, was not formally tested, the results at the time of the analysis did not favor Keytruda over placebo.
Merck is currently conducting further data analyses for both KEYNOTE-867 and KEYNOTE-630 and intends to share the results with the scientific community and regulatory agencies.
This news has resulted in a slight decline in MRK stock, which was down 0.27% at $117.70 at the last check on Thursday.
These decisions highlight the importance of rigorous clinical trial evaluation and the need for therapies to demonstrate both efficacy and a favorable safety profile. While Keytruda remains a valuable treatment option for various cancers, these trial results indicate that further research is needed to identify the optimal settings for its use in these specific indications.
