Cancer Vaccines : Cancer Vaccine Facts

by Food and Drug Administration (FDA)

(Page 3 of 3)

Montgomery started with the Internet and found one NCI study that involved surgery and chemotherapy with an agent different from the one he had before. But the trial was closed. Taking advice from a friend, he checked at the Lombardi Cancer Center at Georgetown University in Washington, D.C. "I was feeling pretty low at this point," he says. He found out the one vaccine study he was interested in had just ended. But a nurse told him that another trial with newer versions of cancer vaccines developed at the NCI was about to start. "There were two slots left," he says. "Luckily, I met the criteria."

Montgomery received a "prime-boost regimen" of Therion Biologics' TRICOM vaccine. He first received an injection in the upper leg of a modified version of the smallpox vaccine to prime the immune system. Then he received monthly boosters of a vaccine called fowlpox CEA (carcinoembryonic antigen), an antigen found on most colorectal and pancreatic cancers. He also received a shot of the hormone GM-CSF, which helps stimulate the cells of the immune system. He had to give some of the injections to himself when he arrived back home in Washington state.

He says he experienced minimal side effects, such as soreness at the site of injection and mild flu-like symptoms. Though most cancer vaccines have been well-tolerated, in other trials some people have experienced autoimmune problems such as inflammation of the thyroid gland, skin disorders, and colitis. Autoimmune conditions are those in which the immune system mistakenly attacks the body's tissues and organs. Before he began the trial, Montgomery signed an informed consent form acknowledging that he was aware of all the risks.

Montgomery continues to participate in the trial and flies to the nation's capital every month to receive treatment because it's been working. "It hasn't cured the cancer," Montgomery says, "but it seems to be keeping it in check. And that's good enough for me."

The Immune System and How It Works

Your immune system includes your spleen, lymph nodes, tonsils, bone marrow, and white blood cells. These all help protect you from getting infections and diseases. When your immune system works the way it should, it can tell the difference between "good" cells that keep you healthy and "bad" cells that make you sick. But sometimes this doesn't happen. Doctors are doing research to learn why some immune systems don't fight off diseases like cancer.

White blood cells are an important part of your immune system. When your doctor or nurse talks about your white blood cells, he or she may use words like:

• Monocytes (MON-o-cites) are types of white blood cells.
• Lymphocytes (LYM-fo-cites) are types of white blood cells.
• B cells, T cells, and "natural killer cells" are kinds of lymphocytes.

Cancer Vaccine Facts

Cancer vaccines are intended either to treat existing cancers (therapeutic vaccines) or to prevent the development of cancer (prophylactic vaccines).

Therapeutic vaccines, which are administered to cancer patients, are designed to treat cancer by stimulating the immune system to recognize and attack human cancer cells without harming normal cells. Prophylactic vaccines, on the other hand, are given to healthy individuals to stimulate the immune system to attack cancer-causing viruses and prevent viral infection.

There is a prophylactic vaccine against hepatitis B virus, an infectious agent associated with liver cancer.

Scientists are currently evaluating several different vaccines in large human trials to determine which approaches are most effective for particular kinds of cancers.

The Role of FDA and NCI

After conducting preclinical research in lab animals, drug companies or clinical investigators submit an investigational new drug application to the Food and Drug Administration, requesting permission to move forward with testing in humans called clinical trials. The agency and the sponsors continue to communicate throughout the three phases of clinical trials, and the FDA ensures that treatments are safe and effective before they can be marketed.

The National Cancer Institute (NCI) is the main federal agency that supports and conducts cancer research. The NCI funds studies conducted by hospitals, universities, and businesses. The institute also supports a network of cancer centers across the country.

Both agencies are part of the U.S. Department of Health and Human Services, and they share responsibility and oversight for clinical trials. In 2003, the FDA and the NCI entered an agreement to enhance the efficiency of clinical research and the evaluation of new cancer medications. An NCI-FDA Oncology Task Force involves senior staff from both agencies and oversees the agreement. The agencies collaborate on developing the markers that show whether a treatment is effective, such as survival time, tumor shrinkage, and time to relapse.

New Cancer Office and Program

In July 2004 the FDA announced plans to create the Office of Oncology Drug Products, which will be housed in the agency's Center for Drug Evaluation and Research (CDER). The new office will consolidate three existing areas within CDER that are responsible for reviewing drugs and biologics used to prevent, diagnose, and treat cancer. The creation of this office will improve the consistency of review and policy toward oncology drugs and bring together oncologists who will help develop new therapies.

"Biomedical research in the United States is second to none, and it is our responsibility to see that patients reap the fruits of that research," says Health and Human Services Secretary Tommy G. Thompson. "We are committed to creating the most effective and efficient review process possible to ensure life-saving treatments are made available to cancer patients."

The FDA also is creating a new oncology program within the office, which will coordinate cancer-related work performed throughout the FDA. The program will promote cross-agency consultation and discussion and the development of regulatory policy and standards, and will serve as a focal point for agency interactions with the National Cancer Institute and other stakeholders.

About the Author

www.fda.gov
FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.