Last month we reported that KEYTRUDA doubles survival rates for some patients over chemo, and it now seems the FDA in the US agrees.

Today, the U.S. Food and Drug Administration (FDA) has approved Keytruda (pembrolizumab) as a first line defence for advanced bowel cancer patients with the genetic mutations MSI-H or dMMR.

The decision comes after promising findings from KEYNOTE-177 (NCT02563002), a Phase 3 trial in which Keytruda more than doubled the time patients lived without signs of disease progression, compared with standard chemotherapy, while lowering the rate of serious adverse events.

With this approval, Keytruda is now the first single-agent immunotherapy — and first alternative to chemotherapy — approved as a first-line treatment for this indication. The decision came less than a month after pharmaceutical company, Merck Sharp Dohme, submitted a supplemental biologics license application (sBLA) requesting this approval.

“This is the first randomized controlled study to show that first-line immunotherapy is significantly better than chemotherapy at shrinking metastatic bowel cancers with these specific DNA mutations, and delaying the time it takes for the cancer to progress,” Kai-Keen Shiu, PhD, MD, an honorary associate professor of oncology at the UCL Cancer Institute, consultant medical oncologist at UCLH, and chief investigator of KEYNOTE-177, said in a university news story.


Keytruda is an immune checkpoint inhibitor that works to prevent a mechanism used by cancer cells to evade immune responses. It specifically targets the PD-1 receptor at the surface of immune T-cells, and prevents it from binding to the PD-L1 protein on cancer cells, removing the brakes from immune cells.

Keytruda has been approved in the U.S. and in the EU to treat different types of cancer, including lung, bladder, stomach, esophageal, and liver cancer, lymphoma, melanoma, and cancers with specific genetic features that failed prior therapies.

KEYTRUDA is registered in New Zealand as an immuno-oncology treatment for advanced melanoma, non­-small cell lung cancer (NSCLC), Hodgkin lymphoma, urothelial cancer, head and neck cancer and MSI-H/dMMR. KEYTRUDA has only been approved and fully funded by PHRMAC for Melanoma.

Interim data from KEYNOTE-177, presented at the American Society of Clinical Oncology (ASCO) 2020 Virtual Annual Meeting, showed that Keytruda prolonged the time patients lived without disease progression from a median of 8.2 to 16.5 months, lowering the risk of death or disease progression by 40%.

“Today’s approval has the potential to change the treatment paradigm for the first-line treatment of patients with MSI-H colorectal cancer, based on the important findings from KEYNOTE-177 that showed Keytruda monotherapy demonstrated superior progression-free survival compared to standard of care chemotherapy,” Roy Baynes, senior vice president and head of global clinical development, and chief medical officer of Merck, said in a press release.