Pembrolizumab is currently in clinical development for unresectable or metastatic microsatellite instability high (MSI-H) or deficient mismatch repair (dMMR) endometrial, gastric, biliary, small intestine, or pancreatic cancer in adult patients. MSH-H or dMMR cancers occur when the process for replicating and repairing DNA (genetic material) is not working properly. When a cells misatch repair system stops working, errors in the DNA start accumulating and may cause cancer. There are currently no treatments recommended for the treatment of MSI-H or dMMR tumours specifically in endometrial, gastric, biliary, small intestine, or pancreatic cancer.
Pembrolizumab intravenous (IV) injection is in a class of medications called monoclonal antibodies. It works by helping the immune system to slow or stop the growth of cancer cells. Pembrolizumab has been shown to be more effective than chemotherapy for MSI-H or dMMR colorectal cancers,and therefore it may also be effective in other cancers with this type of mutation. If licenced, pembrolizumab would offer a treatment option for adults with endometrial, gastric, biliary, small intestine, or pancreatic tumours whose disease has progressed with other treatment approaches and therefore have no satisfactory other treatment options.