Keytruda (pembrolizumab) is a programmed death receptor-1 (PD-1)-blocking monoclonal antibody used to treat a number of different types of cancer. Keytruda is administered via a 30 min intravenous (IV) infusion every 3-6 weeks. A response to treatment is typically seen within 2-4 months of starting treatment with Keytruda, but the time it takes to work will vary based on cancer type and the stage of disease.

Keytruda is a type of immunotherapy that works by preventing cancer cells from hiding from your immune system. Immunotherapy works differently to traditional chemotherapy drugs - it takes time for the immune system to identify and attack cancer cells once Keytruda helps prevent the cancer cells from hiding.

When determining how long Keutruda takes to work, researchers measure the ‘time to response’, which gives the time frame in which you’d expect to see a patient’s cancer show signs that it is responding to treatment.

‘Time to response’ is the time taken from the day a patient is assigned to receive a particular therapy until the first day that the patient has a partial or complete response to the treatment. The ‘time to response’ observed in a number of clinical trials used to gain approval of Keytruda are reported in the table below.

Time to response following treatment with Keytruda