Keytruda is indicated for patients suffering from melanoma, non-small cell lung caner, head and neck squamous cell cancer, classical Hodgkin lymphoma (cHL), primary mediastinal large b-cell lymphoma, urothelial carcinoma, micro satellite instability-high cancer (MSI-H), gastric cancer, cervical cancer, hepatocellular carcinoma, and merkel cell carcinoma (MCC).
Patients should receive 200 mg of Keytruda every three weeks, regardless of the cancer. For pediatric patients suffering from cHL, MSI-H, or MCC, the recommended dosage is 2 mg/kg up to 200 mg every three weeks. If indicated alongisde axitinib, Keytruda should be given at 200 mg every three weeks with 5 mg of axitinib orally twice daily.
Common side effects of taking Keytruda include fatigue; pain in muscles, bones, or joints and abdomen; decreased appetite; itching; diarrhea; nausea; rash; fever; cough; shortness of breath; and constipation. When taken with the chemotherapy medications, side effects include the aforementioned as well as vomiting, hair loss, inflammation of nerves that may cause pain, and weakness and paralysis in the arms and legs.
Pediatric patients may experience a greater development of fatigue, vomiting, abdominal pain, increased level of liver enzymes and decreased levels of sodium in the blood.
Merck warns that these are not comprehensive side effects of Keytruda, and suggest patients alert physicians to the development of any particular side effects after starting the medication.