Researchers studying customized cancer vaccines
■ Because every cancer is unique, scientists seek ways to deliver cost-effective, individualized treatment to each patient.
By Susan J. Landers — Posted Oct. 3, 2005
Washington -- Personalized medicine is coming full circle in cancer treatment. Individualized monoclonal antibodies had their run 30 years ago, and now vaccines that can immunize people against their own tumors hold promise.
Although customized antibodies were effective at fighting tumors, their high cost drove them from favor, and generic versions took their place.
Researchers are returning to the idea of an individualized approach to fighting cancer, but instead of making a monoclonal antibody for each person, they are exploring the possibility of teaching an individual's immune system to make its own antibodies.
Clinical trials are under way, for example, to determine the effectiveness of a cancer vaccine, and results may be forthcoming as early as next year, said Ronald Levy, MD, professor and chief of Stanford University Medical Center's oncology department.
Dr. Levy was the first to generate and use monoclonal antibodies to treat patients with lymphoma. He is now overseeing clinical trials for patients with B cell lymphoma who have been vaccinated against the receptors expressed by their own cancer cells.
"Every person will have a different cancer. This provides both a challenge and an opportunity," said Dr. Levy, who spoke at a Stanford-sponsored seminar on personalized medicine, "One Cure Does Not Fit All."
A costly process
Thirty years ago, Dr. Levy and others personalized cancer treatment by developing a separate antibody for each person, and the results were promising. "In 1982, we showed how this could work in the very first person we tried it on."
About 50 people received the treatment, but it was time-consuming and very expensive. So instead of pursuing the individualized approach, researchers formulated numerous generic antibodies.
Today, with greater understanding of genetics and of how antibodies do their work, researchers have turned, once again, to taking an individualized approach to cancer therapy.
The idea now is to find and purify a tumor cell, modify it and then inject it back into the body with the hope that an immune response will be mounted against the tumor. Patients enrolled in clinical trials first receive standard therapy, and then they are vaccinated.
Of course, developing customized vaccines will be time-consuming and expensive. And should they prove effective, demand will undoubtedly be great, Dr. Levy said. "But if you show that something works, people will get clever and develop new technology that makes it possible to deliver something in real time and in a cost-effective way."
There are additional hurdles to overcome, he noted. The drug industry is more familiar with mass producing medications than customizing them, and the health care delivery system is not attuned to customized therapies but relies on standardized care.
There is a lot to discuss, he said. "But I do think that some of the progress we are going to make in the future, particularly related to cancer, will be related to solving these problems and developing therapies that are more in tune with each individual, not just at the point of delivery, but at the point of design."