Some of the newest and most innovative ways of fighting cancer involve using the body’s immune system. These are called immunotherapy treatments. Usually this type of treatment results in fewer side effects than traditional cancer treatments because the immune system is able to target specific cells without affecting healthy cells.
Keytruda (pembrolizumab) was developed by the global healthcare company, Merck. It is an antibody drug that has been shown to improve a mesothelioma patient’s prognosis.
Keytruda (pembrolizumab) patients receive Keytruda intravenously (IV) for 30 minutes. This treatment is repeated every 21 days for up to 2 years.
Unlike other immunotherapy drugs, Keytruda works to keep the cancer cells from tricking the immune system. Rather than attacking the cancer, Keytruda blocks the proteins that cancerous cells use to suppress the immune system.
In the body, there is a type of white blood cell that watches out for signs of infection or disease and can also attack cancer cells. These white blood cells are called T cells. On the surface of these T cells are certain proteins known as programmed cell death receptors (PD-1). So that T cells don’t destroy healthy cells, they use these surface proteins, or PD-1, to bind to and communicate with PD-L1 and PD-L2, proteins that enable cells to escape attack from the body’s immune system.
PD-L1 is a protein in some people’s bodies that suppresses their immune system. Cancer cells use this protein to keep the immune system from realizing that they are dangerous. If the immune system doesn’t see the threat, it won’t attack the cancer cells.
Keytruda works to block the PD-1 receptor on cancer cells, keeping proteins like PD-L1 from being effective. Without the PD-L1 the immune system recognizes the cancer cells as a threat and can work to destroy them.
In other words, when the PD-1 protein on T cells comes in contact with PD-L1 and PD-L2 proteins, they are given the signal to allow that cell to live and spread. Certain types of cancer cells, however, have been found to contain an excess of these PD-L1 and PD-L2 proteins, making them look like healthy cells to the immune system, thus allowing them to avoid getting destroyed by T cells.
Pembrolizumab blocks that signal so that the T cells aren’t misled by PD-L1 and PD-L2, allowing the body’s natural immune system to attack the cancer cells. This particular therapy is called an immune checkpoint blockade, where “checkpoint” refers to the encounter between T cells and the PD-L1 protein on tumor cells.
So far, Keytruda has had incredible results. Early findings showed 48 percent of patients were able to stabilize their condition and 28 percent of patients saw improvement in their condition. In other words 76 percent of patients had their condition under control because of Keytruda.
Keytruda® is well-tolerated by mesothelioma patients.
This article was written with the reproduction of paragraphs from:
Mesothelioma Cancer Alliance – Keytruda (Pembrolizumab);
Mesothelioma Guide – Phase II Anti-PD-1 Immunotherapy for Mesothelioma