Immunotherapy enhances the immune system to treat diseases. Immunotherapy is being heavily researched as a potential treatment for certain types of cancer, including mesothelioma.
Mesothelioma immunotherapy drugs are still considered an emerging treatment, used mostly in clinical trials. However, some forms of immunotherapy, such as pembrolizumab (Keytruda) and bevacizumab (Avastin) have already shown promise as effective ways to treat mesothelioma.
Immunotherapy comes in two primary forms: active and passive. Each of these forms of immunotherapy can be specific (i.e., target a particular type of cancer) or non-specific (i.e., prompts a general immune response).
Stimulate the body’s own immune system to attack and kill cancer cells. Types include:
- Cellular Therapy
- Adjuvant Therapy
- Cancer Vaccines
Introduce synthetic immune proteins into the body to fight cancer. Types include:
- Monoclonal Antibodies
- Tumor Cell Modulation
- Tumor-Infiltrating Lymphocytes
How Immunotherapy Can Treat Mesothelioma
The most promising immunotherapy drugs with respect to treating mesothelioma are what are known as monoclonal antibodies (or “mab”s). These are passive immunotherapy drugs that target a particular kind of cell or antigen rather than stimulating the entire immune system. Typically, the generic names of monoclonal antibodies end with the suffix -mab, such as pembrolizumab or bevacizumab.
Currently, immunotherapy treatments for mesothelioma are in various phases of the clinical trial process. Patients whose cancer does not respond to other forms of therapy may be eligible to participate in a trial for one of these immunotherapies, if they meet the trial criteria.
Mesothelioma Immunotherapy Drugs
While only a handful of immunotherapy drugs have been granted approval by the U.S Food and Drug Administration (FDA), many more are currently in clinical trials to determine what impact they may have in stimulating the human body’s immune system to fight cancer.
Keytruda works by targeting the PD-1/PD-L1 pathway of cancer cells, which in turn activates programmed cell death in those cells. Keytruda has been approved to treat melanoma, non-small-cell lung cancer (NSCLC), and metastatic head and neck squamous cell carcinoma (HNSCC). It has also shown promising results for some mesothelioma patients in clinical trials, although the FDA has not yet approved it to treat mesothelioma.
Fast-growing tumors require blood to sustain their growth. Avastin works by preventing new blood vessels from forming, effectively starving the tumors. While Avastin has not yet been approved by the FDA to treat mesothelioma, it has been approved to treat many other types of cancers, including cervical cancer, colorectal cancer, ovarian cancer, NSCLC, and others. In July 2016, the National Comprehensive Cancer Network (NCCN) updated its first-line treatment recommendation for unresectable (non-operable) pleural mesothelioma to include bevacizumab along with standard chemotherapy treatments.
Another PD-1/PD-L1 inhibitor, Tecentriq has been approved to treat metastatic NSCLC that had progressed while the patient was undergoing chemotherapy. Although it has not been approved yet for mesothelioma, atezolizumab is being studied for its effect on mesothelioma, as well as other types of cancer.
Immunotherapy Research and Funding
In the last few years, a lot of attention has been given to immunotherapy for mesothelioma and other types of cancer due to the potential for a more effective treatment, and possibly even a cure, to be developed from this method. Efforts such as the Cancer Moonshot Initiative and tech entrepreneur Sean Parker’s $250 million cancer commitment to immunotherapy research have helped to further these efforts.Sources
American Cancer Society. What is cancer immunotherapy? Cancer.org. Created July 23, 2015. Updated August 8, 2016.
American Society of Clinical Oncology. What are Cancer Vaccines? Cancer.Net. Updated December 2015.
Furlow B. FDA Approves Atezolizumab for Refractory Metastatic Non-Small Cell Lung Cancer. OncoTherapy Network. October 20, 2016.
National Cancer Institute. FDA Approval for Bevacizumab. Cancer.gov. December 4, 2014.Ribas A. Releasing the Brakes on Cancer Immunotherapy. New England Journal of Medicine. October 15, 2015. 2015;373:1490-1492. doi: 10.1056/NEJMp1510079