JOHN WAYNE CANCER INSTITUTE BEGINS WORLDWIDE TESTING OF MELANOMA CANCER VACCINE…THANKS TO ONE MAN'S VISION
Fulfilling a life-long dream may be impossible for some, but not for tenacious individuals like Donald L. Morton, M.D., whose vision and work toward a treatment for deadly skin cancer has remained an insatiable passion for the past 35 years. It is due to his profound questioning and unshakable persistence that the John Wayne Cancer Institute at Saint John's Health Center received a $26.8 million five-year grant from the National Cancer Institute (NCI) to begin final testing of a vaccine used to treat melanoma. One of the largest grants funded by the NCI in the last year for a single clinical cancer study, the funding will allow researchers at the institute to begin worldwide "Phase III" testing of the vaccine in patients with advanced "Stage III" (advanced to lymph glands), and a second grant from the NCI to perform similar studies in "Stage IV" (advanced to other parts of the body) melanoma.
The idea of a cancer vaccine began many years ago when Dr. Morton found himself intrigued by journal reports of patients having a seemingly miraculous disappearance of cancer following a fever. He also began to wonder why some cancer patients remain healthy for decades, then suddenly have a reappearance of cancer soon after an accident or death of a loved one-events that were known to depress the immune system. These accounts led Dr. Morton to consider that the body's key to fighting cancer are the infection-fighting white blood cells, provided they could somehow be encouraged to attack cancer cells in the same way they track down and kill bacteria and viruses.
His initial experiments in mice and guinea pigs gave initial proof that his theory was correct. Dr. Morton discovered that infections of tuberculosis-causing bacteria combined with cancer cells stimulated these animals to reject their cancers.
Following many months of detailed initial testing, Dr. Morton was ready to try the experiment on human patients. But what kind of cancer patient would be the best candidate? He surmised that because malignant melanoma has a higher incidence of temporary remission than other types of cancer, it is, therefore, the most prone to attack from the body's own immune defenses. For this reason, Dr. Morton began recruiting patients with malignant melanoma to take part in his study. If melanoma spreads from its initial site, patients seldom survive more than six to eight months after they are diagnosed.
In 1967, Dr. Morton gathered eight melanoma patients with tumors that had spread to multiple sites on the surface of their skin. He infected their tumors with BCG Vaccine, a vaccine used to prevent tuberculosis. It was his belief that alerting the immune system to the presence of a foreign invader, in this case a weakened version of the TB bacteria, would cause white cells to attack the skin cancer as well. It worked. Five of the eight patients had regression of the skin tumors and several stayed in remission for five to ten years. However this approach would have little success in treating cancer inside the body, such as tumors in the lungs, liver or brain. Direct infection would simply not work. That's when Dr. Morton turned to a 200-year-old idea: creating a vaccine.
In 1776, patients were given a live, but weakened cow pox virus, which was found to prevent the development of small pox, a disease caused by a similar virus. Since then, researchers had developed vaccines to prevent polio, measles and typhoid. Dr. Morton reasoned the same approach could be used to treat tumors inside the body.
Dr. Morton developed several variations of the cancer vaccine in the 1970's, however, he didn't consider the first three formulations successful because they boosted an immune response in only one out of three patients and were not effective in causing cancer regression.
A breakthrough occurred in the early 1980's, when Dr. Morton's team of researchers discovered why several cancers wildly excite the immune system while others do not; these cells have a protein or carbohydrate/fatty coating called antigens which alert white cells and identify the mutant invaders.
Dr. Morton had an unusual opportunity to take these new research finding and further the development of a cancer vaccine. During the last 25 years, he has saved nearly one million blood, tissue and serum samples from the thousands of patients he has treated. "It's a very unique resource," according to Dr. Morton. "As far as I know, there is no collection of this scale anywhere else in the world which has been ongoing for so many years."
After months of testing his samples, he learned that only three types of cancer cells would arouse the immune system's strongest and broadest response. He used radiation to weaken live tumor cells (harvested from other patients and grown in the laboratory), combined them with BCG bacteria, and thus had the genesis for his melanoma vaccine.
During the last 14 years, Dr. Morton has used the vaccine on more than 1,500 patients. To date, preliminary reports have found the vaccine raises a strong immune response in more than 90 percent of patients who receive it. In those patients who respond, it has increased life span three-fold, with virtually no side effects when the vaccine is given as a post-surgery treatment. In vaccine patients who respond, the five-year survival rate in Stage III patients is 52 percent and in Stage IV it is 42 percent, compared to less than 10 percent in untreated patients.
Now, thirty-five years later, Dr. Morton's original hypothesis has resulted in a cancer vaccine, which is in the final (Phase III) stage of testing for approval by the Food and Drug Administration for widespread use. As a result of years of solid detective work, the vaccine may soon be available to help tens of thousands of cancer patients around the world battle this deadly disease.
The John Wayne Cancer Institute