A phase III trial evaluating Keytruda monotherapy demonstrated a significant reduction in risk of disease progression in death in microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) unresectable or metastatic colorectal cancer.
Results from KEYNOTE-177, a phase III trial evaluating KEYTRUDA, Merck’s anti-PD-1 therapy, showed that Keytruda monotherapy reduced risk of disease progression or death by 40% (HR=0.60 [95% CI, 0.45-0.80; p=0.0002]) and showed a median progression-free survival of 16.5 months compared with 8.2 months for patients treated with chemotherapy (investigator’s choice of mFOLFOX6 or FOLFIRI, with or without bevacizumab or cetuximab), a current standard of care in this patient population.
As previously announced, the study will continue without changes to evaluate overall survival, the other dual primary endpoint. These results were selected for presentation on Sunday, May 31, 2020 in the plenary session of the virtual scientific program of the 2020 American Society of Clinical Oncology annual meeting (Abstract #LBA4).
“For many years, the standard of care for the first-line treatment of patients with MSI-H colorectal cancer has been the combination of mFOLFOX6 plus bevacizumab. This is the first time a single-agent, anti-PD-1 therapy demonstrated a superior, statistically significant and clinically meaningful improvement in progression-free survival, compared to chemotherapy for these patients,” Roy Baynes, senior vice president and head of global clinical development, chief medical officer, Merck Research Laboratories, said in a statement.
“Keytruda monotherapy significantly reduced the risk of disease progression or death by 40% versus standard of care chemotherapy, with fewer treatment-related adverse events observed, in patients with MSI-H metastatic colorectal cancer. Keytruda also demonstrated a long-term, durable response that lasted over two years for those who responded to treatment,” Thierry Andre, professor of medical oncology at Sorbonne University, and head of the Medical Oncology Department in St. Antoine Hospital, Assistance Publique Hôpitaux de Paris, said in a statement.
In May 2017, Keytruda was the first cancer therapy approved by FDA for use based on a biomarker, regardless of tumor type, in previously treated patients with MSI-H or dMMR solid tumors.
