The UK’s National Institute for Health and Care Excellence (NICE) has recommended Keytruda for NHS use as a first-line treatment for colorectal cancer patients with rare mutations.
The draft guidance recommends Merck & Co’s – known as MSD outside the US and Canada – Keytruda (pembrolizumab) for the treatment of patients with previously untreated metastatic colorectal cancers with high levels of microsatellite instability (MSI-H) or DNA mismatch repair deficiency (dMMR).
In the phase 3 KEYNOTE-177 trial, Keytruda was found to slow or halt progression of metastatic MSI-H/dMMR colorectal cancers for a median of 16.5 months versus 8.2 months for chemotherapy.
In addition, 48.3% of patients receiving Keytruda lived 24 or months without their cancer progressing, compared with 18.6% in the chemotherapy group.
In a statement, NICE said that although the clinical trial evidence showed an increase in progression-free survival for Keytruda in these patients, its independent appraisal committee said the long-term evidence is ‘limited’.
As a result, NICE recommends that Keytruda treatment should be stopped at two years if there is no evidence that a person’s disease has progressed.
Merck & Co added in its own statement that the KEYNOTE-177 trial is still ongoing to assess the impact on patients’ overall survival with Keytruda treatment.
“There are currently no specific treatments for untreated metastatic colorectal cancer with high microsatellite instability or mismatch repair deficiency. [Keytruda] has shown the potential to extend the lives of hundreds of people with this form of colorectal cancer,” said Meindert Boysen, deputy chief executive and director of the Centre for Health Technology Evaluation at NICE.
“It also works in a different way to current standard care with chemotherapy and the committee heard that people appreciated its faster and less frequent administration, and preferable adverse effects compared with chemotherapy. We are pleased, therefore, to be able to recommend [Keytruda] for routine use in the NHS,” he added.
Cells that are mismatch repair (MMR) deficient often have many DNA mutations, and are commonly found in colorectal, gastrointestinal and endometrial cancer.
High MSI or MMR deficiency is observed in approximately 4% of metastatic colorectal cancer patients, and about 450 patients in England will become eligible for Keytruda treatment.
Patients with these mutations face a poorer prognosis as well as a greater risk of death than colorectal cancer that is microsatellite stable.