Vaccines, as you probably know, are medicines that help your body fight disease. If you’re like most people, you received vaccinations against a bunch of disorders – from chickenpox to whooping cough – when you were a kid. Vaccines work with your immune system to recognize and destroy harmful substances, such as disease-causing viruses, that attack your body.
Scientists today are exploring new and better ways to boost the power of the immune system, using vaccines aimed at battling cancer. Cancer vaccines can be used to prevent or treat cancer.
Preventive vaccines currently available include the HPV vaccine, which protects against human papillomavirus (HPV). An HPV infection can lead to cervical, vaginal, vulvar and anal cancer. The hepatitis B vaccine is another preventive cancer vaccine. Hepatitis B infection can cause liver cancer.
Vaccines to treat cancer are a type of immunotherapy because they work directly with your body’s immune system. Cancer treatment vaccines can do several things. These include destroying residual cancer cells after other treatments, stop a tumor from growing or spreading, and prevent cancer that was treated from coming back.
Currently, there are only a handful of active immunotherapies that are approved for treating cancer. There are, however, hundreds more being investigated in clinical trials, in which cancer patients can participate. Clinical trials are research studies that test the safety and effectiveness of new medications, therapies or devices.
While there are numerous cancer clinical trials ongoing, estimates suggest only three percent to six percent of eligible cancer patients participate in them. This not only slows the progress of new treatment development, it also means more than 90 percent of cancer patients may be missing out on potentially life-saving new treatments.
An example is a vaccine developed by researchers at the University of California San Diego Health and the La Jolla Institute for Allergy and Immunology, which is currently in clinical trials. This vaccine, which is for people with deadly metastatic cancer, is specifically created to match each patient’s cancer mutations and immune system.
Study researchers begin by testing patients’ tumors and identifying the neoantigens, or mutations, that cause their immune systems to respond. Researchers then culture the neoantigens with the patients’ T-cells, a type of immune system cell, and give patients a series of three vaccines of the modified T-cells.
To ensure the T-cells remain activated once they reach patients’ tumors, researchers also give patients the immunotherapy medication Keytruda. The bolstered T-cells then go to work destroying the tumor cells.
Another clinical trial, led by researchers at Stanford University School of Medicine, tested a combination immunotherapy for the treatment of two types of non-Hodgkin’s lymphoma, a type of blood cancer. The two types are diffuse large B-cell lymphoma and follicular lymphoma.
The treatment tested was a combination of an experimental antibody developed by researchers at Stanford and a commercially available anti-cancer antibody called rituximab.
The experimental antibody works by blocking CD47, a protein that inhibits immune cells called macrophages from attacking and devouring cancer cells. Rituximab amplifies signals to the macrophages to do their job of consuming the cancer cells.
The results of this small, multicenter clinical trial are promising. Half of the 22 people enrolled in phase 1 of the trial had a positive response to the therapy, and about one-third went into complete remission.
These are just two examples of clinical trials looking at new cancer treatments that take advantage of patients’ disease-fighting immune systems. Researchers are hosting many more trials to test vaccines for other types of cancer.
These include cancer of the bladder, breast, cervix, colon, rectum, kidneys, lungs, pancreas and prostate. Other clinical trials are investigating treatments for brain tumors, leukemia, melanoma and myeloma.
If you’re interested in participating in a clinical trial, talk with your doctor about appropriate studies for your situation. You can also look for clinical trials being conducted in your area at clinicaltrials.gov.
By participating in a clinical trial, you may discover a life-altering treatment that works for you when others have failed. You may also help make a new therapy available to others with cancer who previously had no hope. Talk to your doctor and consider taking part in a clinical trial.