The mesothelioma community is hearing about different immunotherapy options that are currently being researched. To review – cancer immunotherapy is an emerging avenue to treat cancer. This promising line of research has become an important part of treating some cancers. Immunotherapy is treatment that uses part of a person’s immune system to fight cancer. The immune system is a unique system comprised of organs, special cells, and substances that help protect from germs that can lead to infections and diseases. The immune system is the body’s protector to help maintain health. Usually the immune system can recognize foreign substances but since some cancers are known cells that start replicating wildly, the immune system is slow to respond and doesn’t recognize cancer cells as foreign. Researchers have found different prototypes to help the immune system recognize cancer cells and strengthen its response. The main types of immunotherapy that are now being used:
- Monoclonal antibodies: man- made versions of immune system proteins- substances found in the immune system- designed to attack a very specific part of the cancer cell.
- Immune checkpoint inhibitors: drugs that take the brakes off the immune system which help it recognize and attack cancer cells
- Cancer vaccines: substances injected into the body to start an immune response against certain cancers
- Non-specific immunotherapies boost the immune system in a general way and help the system attack cancer cells.
Immune checkpoint inhibitors have the ability to distinguish between normal cells in the body and those it sees as “foreign.” These allow the immune system to attack the foreign cells while leaving the normal cells alone. PD-1 is a protein on immune T cells. It acts as a type of on and off switch that keeps T cells from attacking other cells in the body. Progress has been made in this area with drugs that target PD-1 -Pembrolizumab (Keytruda) and Nivolumab (Opdivo).
One of these types of immunotherapy- immune checkpoint inhibitors- is showing some early promising results in clinical trials. In an article written by Giovanni Luca Ceresoli, Maria Bonomi, and Maria Gratzia Sauta, “Immune Checkpoint Inhibitors in Malignant Pleural Mesothelioma: Promises and Challenges,” published in May of 2016 indicates that Phase 1 Trials involving PD-1 and PD-L1 inhibitors are ongoing with early promising results. One of the most promising statements from the article is, “the emergence of these new therapies is going to change the whole cancer therapy scenario in the next few years. Based on this upcoming evidence, therapy with immune checkpoint inhibitors is being evaluated also in patients with malignant pleural mesothelioma.”
As these early results are promising it takes time and money to continually evaluate the response of the new drugs in the treatment of malignant pleural mesothelioma. The fact that they are being used for certain cancers is an encouraging sign that they might be helpful in mesothelioma. Once again seeing these results reminds us of the vital importance of participation in clinical trials.