Researchers: New vaccine can stop lung cancer

<br>DALLAS (AP) _ An experimental vaccine wiped out lung cancer in some patients and slowed its spread in others in a small but promising study, researchers say. <br><br>Three patients injected with the

Thursday, February 19th 2004, 12:00 am

By: News On 6

DALLAS (AP) _ An experimental vaccine wiped out lung cancer in some patients and slowed its spread in others in a small but promising study, researchers say.

Three patients injected with the vaccine, GVAX, had no recurrence of lung cancer for more than three years afterward, according to the study of 43 people with the most common form of the disease, non-small cell lung cancer.

The findings were published in Wednesday's Journal of the National Cancer Institute. The research was funded in part by CellGenesis, a pharmaceutical company that hopes to produce the vaccine.

The vaccine, developed by researchers at Baylor University Medical Center in Dallas, is years away from reaching the market, if ever. The researchers hope to apply for Food and Drug Administration approval in three years.

"The results are very promising for patients with non-small (cell) lung cancer, which is frequently resistant to chemotherapy," said Dr. John Nemunaitis, a Baylor oncologist who led the study.

Non-small cell lung cancer is the nation's leading cause of cancer death, killing more than 150,000 people each year. The disease is related to smoking and is often difficult to treat. Treatment usually involves removal of the tumor, chemotherapy or both.

The study is the first to show complete and long-lasting regression of lung cancer by stimulating the immune system to attack cancer cells, Nemunaitis said. A similar approach has shown promise against skin and renal cell cancer.

In the study, each patient was injected in the arm and leg with a vaccine that included cells from his or her tumors. A gene called CM-CSF was placed into the cancer cells to change the surface of the cells to help the body identify them as cancerous. The body's immune cells soon began to recognize, attack and destroy the cancer cells in the lungs.

Forty-three lung cancer patients _ 10 in the early stage and 33 in the advanced stage _ were injected with the vaccine every two weeks for three months. Researchers followed them for three years.

The cancer disappeared in three of the advanced-stage patients. Two of those patients previously had chemotherapy, which failed. In the rest of the advanced-stage patients, the disease remained stable and did not spread for almost five months to more than two years.

For patients in the early stage, the vaccine did not make much difference against the cancer.

"The most exciting thing is in those who responded to the vaccine, it was complete," Nemunaitis said. "It's given us a lot of encouragement."

For patients with advanced-stage lung cancer, chemotherapy works no more than 3 percent of the time, and survival is usually eight to nine months. Those whose cancer went into remission with the vaccine were alive at least three years later. And the vaccine has no side effects, Nemunaitis said.

Dr. Anwar Khurshid, an oncologist at the Arlington Cancer Center, said the findings will "open a lot of avenues."

"I think you'll cure some patients but not everyone. That's what has been proven in other cases," he said. "You need to vaccine earlier or combine with something else to cure more people."