Immune-system vaccines to fight cancer are advancing but still have a way to go

By ALAN BAVLEY

The Kansas City Star

August 16, 2010
Cancer patient Larry Mathews of Green Bay, Wis., recently was injected with a vaccine made from his own tumor cells. At St. Luke’s Hospital, Jennifer McIntire gave the shot.

The vaccine that Larry Mathews is getting won’t protect him from the flu. That’s OK — the stakes are far higher than that.

He’s hoping the shots will prime his immune system to fight the aggressive cancer that has invaded his brain. If it works as he wants it to, his body’s own killer cells will mop up malignant cells that surgery, radiation and chemotherapy couldn’t eliminate.

For decades, scientists have been trying to create vaccines to recruit the body’s immune system to destroy cancer cells the way it wipes out foreign viruses and bacteria.

After many false starts and premature promises, it appears that their research is beginning to pay off.

In late April, the U.S. Food and Drug Administration approved a cancer vaccine, Provenge, that can modestly extend the lives of men with advanced prostate cancer. Several major insurance plans and Medicare claims processors in some parts of the country, including Kansas and Missouri, already have agreed to pay for the costly treatment.

Mathews is taking part in a preliminary clinical study at St. Luke’s Hospital on a brain cancer vaccine developed at the University of Kansas Medical Center. A larger two-year study aimed at gaining FDA approval is planned to start this fall.

Worldwide, scientists are working on dozens of vaccines against melanoma, breast cancer and cancers of the lung, colon and pancreas.

Researchers can cite anecdotes of cancer patients given months to live who have survived 15 years or longer after receiving vaccines. But so far, conclusive evidence from large clinical trials is scant.

Even so, experts anticipate that several cancer vaccines could prove effective enough to gain FDA approval in the next four or five years.

These therapeutic vaccines are designed for patients who already have cancer. That makes them radically different from conventional preventive vaccines, such as the cervical cancer vaccine Gardasil, that immunize against viruses that cause cancer.

The surge in development of therapeutic vaccines doesn’t come from any single scientific breakthrough, said William Chambers, director of clinical research and immunology at the American Cancer Society. Rather, it’s the result of years of slow, incremental progress.

“Immunotherapy has been a tough nut to crack,” Chambers said. “What you’re seeing now is the product of a lot of hard work. Some of the successes are showing up.”

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Author: Leslie Carol Botha

Author, publisher, radio talk show host and internationally recognized expert on women's hormone cycles. Social/political activist on Gardasil the HPV vaccine for adolescent girls. Co-author of "Understanding Your Mood, Mind and Hormone Cycle." Honorary advisory board member for the Foundation for the Study of Cycles and member of the Society for Menstrual Cycle Research.