Immunotherapy and Lung Cancer
Immunotherapy is very new for treating lung cancer. Today, almost all lung cancer patients treated with immunotherapy have advanced cancers.
Right now, only two immunotherapy treatments are approved by the Food and Drug Administration (FDA). All other immunotherapy treatment options are available through clinical trials. If you are interested in immunotherapy, talk with your doctor about your options, including a clinical trial.
Types of Immunotherapy
Immune Checkpoint Inhibitors
One way cancer cells escape the immune system is to “fool” the body into turning its own defenses off. The ability to turn off is a necessary “checkpoint” that protects normal tissue from being attacked by the immune system--much like the brakes in a car.
Immune checkpoint inhibitors work either by preventing the tumor from putting on the brakes, or stimulating the immune response. Immune checkpoint inhibitors include:
- PD-1 Inhibitors: Target an immune checkpoint found on T cells. Cancer cells can use the PD 1 pathway to deactivate T cells and escape from the immune system. A number of new drugs that prevent cancer cells from doing that are being tested for lung cancer and other cancer types. The results to date are very promising. While not everyone responds to the PD-1 inhibitors, the response rates are higher than with other approaches. The people who do benefit often have excellent responses that can last for long periods of time. Another source of excitement about PD-1 inhibitors is the side effects of these drugs are usually relatively minor and most people are able to tolerate them well. They include fatigue, itching, diarrhea and skin rashes. There are also people who cannot take these drugs because they have certain medical conditions. In March 2015, the FDA granted nivolumab (Opdivo®) expanded approval to treat people with metastatic squamous non-small cell lung cancer who no longer respond after chemotherapy. In 2016, pembrolizumab (Keytruda®) was approved by the FDA to treat people with metastatic non-small cell lung cancer who expressed PD-L1 and no longer respond after chemotherapy. Then in 2016, Keytruda® was appoved as a first-line therapy to treat people with metastatic non-small cell lung cancer who expressed high levels of PD-L1 (greater or equal to 50%). A number of new drugs are also being tested in clinical trials for lung cancer as well as other cancer types.
- CTLA-4 Targeted Monoclonal Antibodies: These drugs are manmade antibodies that act like the ones our bodies produce naturally. They work by activating T cells so they can seek out and destroy cancer cells. Ipilimumab (Yervoy®), used to treat advanced melanoma, is now being studied for a number of other tumors, including non-small cell lung cancer and small cell lung cancers. Side effects of ipilimumab and similar drugs include fever, rashes, stomach and colon problems, itching, fatigue and problems with the thyroid or other glands. Most people are able to tolerate these side effects well, but in some, they are severe. Tremelimumab is another monoclonal antibody being tested in the treatment of mesothelioma.
These drugs target “tumor specific antigens,” characteristics expressed by the cancer cells that mark them as different or abnormal. MAGE-3 is an antigen expressed in 42% of lung cancers and NY-ESO-1 in about 30% of lung cancers. These targets provide promising approaches for new lung cancer vaccines, but they are not the only ones. There are a number of potential targets, many of which are being tested in clinical trials today.
There are also currently trials to determine if vaccines can delay or prevent recurrence in people with lung cancers that are high risk to return or spread.
Adoptive T Cell Therapy
This is an approach in which T cells are removed from an individual with cancer then put through a special process that “re-engineers” them to seek out and destroy cancer cells. This technique has shown promising results in treating certain types of leukemia and lymphoma and is now being tested in a number of cancers, including lung cancer.
The Future of Immunotherapy for Lung Cancer
There is tremendous excitement about the potential of immunotherapy to improve both the length and quality of life, but there is also a great deal of work to done and much to be learned about how these treatments work.
New approaches to treating lung cancer are offering hope and making a difference for people facing lung cancer. As researchers learn more about the ways in which the immune system interacts with lung cancers, there is promise for changing the possibilities for people with lung cancer