The missiles doctors send to fight cancer in a patient have a new ICBM: immunotherapy. This revolution in cancer treatment has serious implications for patients and people wanting to prevent cancer.
For years the standard attack plan to fight cancer was catch it early, at stage I when it is most curable, and use surgery, radiation and chemotherapy to get the highest cure rates. But for the past several years and especially in the last few months, doctors and patients have new therapies to use to control the cancers. These new therapies are immunotherapy, and targeted treatments, precision drugs, improved hormonal agents, and biotherapies.
The most exciting of these new treatments are the FDA approved immunotherapies. For a long time, scientists have recognized that the body’s immune system has been sluggish to fight cancer once it has appeared.
Beginning in 1990 new types of treatments were developed that enhanced the immune system to overcome its otherwise low activity. The first was the drug ipilimumab (Yervoy), which targeted immune system blockade (CTLA-4) and resulted in increased immunologic T cells in the body to more effectively kill cancer cells. This was initially approved for advanced metastatic melanoma, but today it is also used in localized melanoma at high risk of recurrence, and is showing remarkable anti-cancer effects in combined treatments of lung cancer and other tumors. It was approved by the FDA “way back” in March 2011.
Then, another class of immunotherapy drugs was discovered that targeted another biological pathway (PD1-PDL1) that kept the immune system in check, preventing it from fighting cancer. The first 2 drugs used to stimulate the immune system nivolumab (Opdivo) and pembrolizumab (Keytruda) were found to produce remarkably long remissions in some patients with melanomas and kidney cancers. Today, these drugs are approved by FDA for use in many different cancers (lung, bladder, head and neck cancers). You have probably seen television ads for them without realizing that they represent the immunology of the future.
Most surprisingly, the FDA has even approved pembrolizumab for use not based on the type of cancer which a patient has (the standard approval mechanism in the past), but instead based on whether a cancer (regardless of cancer origin, like breast cancer or like lung cancer) shows unstable DNA changes (called microsatellite instability high, or MSI high). This is a first for the FDA, and a welcome change based on improved scientific discoveries.
Because of the success of nivolumab and pembrolizumab, other drug companies have produced drugs which also attach the PD1-PDL1 immune pathway and are now approved by the FDA, including atezolizumab (Tecentriq), avelumab (Bavencio) and durvalumab (Imfinzi). Oncologists and patients have many choices.
Thanks to pioneering work in laboratories, scientists have also been able to take the body’s immune cells and enhance them in test tubes to fight cancer or leukemia in a patient’s body. Inside a patient, immune T cells can kill cancer, but in the past were not active enough to control the cancer. By using special protein antigens, the activity of these T cells can be improved. The system is called CAR T cell therapy. On August 30, 2017, , the FDA approved the first CAR T cell immunotherapy of this type, called trisagenleleucel (Kimriah), to produce long remissions (probably cures) in children or young adults with acute lymphoblastic leukemia. Today, other antigens are being used to stimulate T cells to fight other leukemias, myeloma, lymphoma, and solid tumors like glioblastoma, to further extend CAR T cell therapy.
The hope for using the immune system to fight cancer is actually very old. In 1890 the Coley vaccine was first tested but had little effectiveness. In 1976, BCG (a type of weakened bacteria) was used in bladder cancer (and is still used today). Monoclonal antibodies appeared in 1978, interferon in 1986, and interleukin 2 in 1998.
As well, other immunotherapies have been found useful, and have been approved by the FDA. These include enhanced killer T cell therapy against prostate cancer called sipileucel-T (Provenge) , and monoclonal antibody therapies such as rituximab (Rituxin,) against lymphomas, daratumumab (Darzalex) against myeloma, cetuximab (Erbitux) against lung and head and neck cancers, and bevacizumab (Avastin) against breast and stomach cancers.
The immune system has also been used to prevent cancer. Vaccines which prevent cancer include hepatitis B vaccine (to prevent liver cancer), and HPV vaccines (like Gardasil, Gardasil 9, and Cervarix) to prevent cervix, vagina, penis and head and neck cancers.
So here are Dr. Cary’s tips for using your immune system to prevent and fight cancer.
· Be certain you have received hepatitis B vaccine. Check with your doctor about giving both boys and girls the complete set of 2 or 3 HPV (human papilloma virus) vaccine shots between ages 9 and 26.
· If you have cancer, be certain to ask your oncologist if there is an immunotherapy for your condition, and review the side effects and benefits with her/him. Also ask if the oncologist has tested the cancer to see if it has the changes that predict good effectiveness of some types of immunotherapy (like MSI testing or PDL1 activity).
· If there is no immunotherapy medicine approved for your condition, ask your doctor if you can go to a university or research center oncologist who may have a clinical trial of immunotherapy available for you.. You can find out more about second opinions and clinical trials on my website and book Surviving American Medicine.
Immunotherapy is established as a very active part of anti-cancer treatments. Be sure you have the latest information to help you choose the best treatment for you. And remember to get your cancer preventive vaccines.