Immunotherapy is a new class of cancer treatment that uses the power of your own immune system to fight cancer. This treatment approach uses substances made by the body or in a laboratory to stimulate or direct the immune system to recognize and attack cancer cells. Several immunotherapies are now FDA-approved for lung cancer, and more are offered through clinical trials.
What are immune checkpoint inhibitors?
Many cancer cells are able to grow because they’ve learned how to switch off the body’s immune response. PD-1 and PD-L1 are proteins found in many body cells. PD-1 is also found on the body’s T cells (special white blood cells that are part of the immune system), and the protein serves as a check, or off-switch to keep the T cells from attacking your body’s normal cells. PD-1 attaches to PD-L1 and this interaction between them communicates to the T cells that all is well, there’s no need to attack, and switches off the immune response.
Some cancer cells have large amounts of the PD-L1 protein, and when they communicate to the T cells to switch off the immune response, the cancer is able to grow, unchecked by the T cells and other parts of the immune system. Drugs that target or inhibit the PD-1 or PD-L1 proteins prevent them from attaching to each other, making cancer cells with large amounts of PD-L1 protein no longer “safe” from the T cells. Immunotherapy drugs that have been approved so far include:
- Atezolizumab (Tecentriq)
- Durvalumab (Imfinzi)
- Nivolumab (Opdivo®)
- Pembrolizumab (Keytruda)
CIMAvax-EGF lung cancer vaccine
The CIMAvax-EGF vaccine is lung cancer immunotherapy that was developed in Cuba and is now available in the United States only through a clinical trial at Roswell Park. Our trial uses the CIMAvax-EGF vaccine in combination with the anti-PD1 checkpoint inhibitor nivolumab (Opdivo®) in patients previously treated for advanced non-small cell lung cancer (NSCLC).
The vaccine blocks a protein called epidermal growth factor (EGF) that cancer cells need to grow. Blocking this protein prevents the EGF from attaching to its proper receptor on the cancer cell, a connection that’s necessary for the cancer cell to grow and proliferate. By “starving” the cancer cells of the EGF, they can no longer multiply.