Drug study for brain cancer shows promising results

A clinical study conducted at Henry Ford Hospital on the use of a drug to extend the survival of patients with the most common and aggressive type of brain cancer, has yielded results that were significantly better than expected.

The randomized Phase II study focused on patients with glioblastoma multiforme (GBM), whose cancer had recurred after first- or second-line therapy. The study revealed that more than a third who were treated with Avastin (bevacizumab) alone, as well as more than half of those treated with Avastin in combination with the chemotherapy drug irinotecan, lived without further progression of the disease for a period of six months. In addition, no new or unexpected adverse effects from the use of Avastin were observed during the study.

“This is very encouraging news,” says Tom Mikkelsen, M.D., a neuro-oncologist who is the study's principal investigator at Henry Ford and co-director of the Hermelin Brain Tumor Center. "Historical estimates suggest that only 15 percent of patients with this aggressive type of brain cancer live without their cancer progressing within six months. Although gliomas [fast-growing malignant brain tumors] are nearly always incurable, use of a drug like Avastin may help to buy precious time for patients, as well as to preserve their physical and mental functions longer than was previously possible.”

Avastin is a therapeutic antibody designed to inhibit Vascular Endothelial Growth Factor (VEGF), a protein that stimulates development of new blood vessels in a process known as angiogenesis, while maintaining existing tumor vessels. By binding to VEGF, Avastin acts as an anti-angiogenesis agent that chokes off the blood supply to tumors, which in turn inhibits their growth and metastasis.

The national study is sponsored by Genentech and Henry Ford Hospital is one of the large study sites.

“The same process that makes gliomas so deadly may turn out to be exactly the same thing that makes it possible to slow down their progression,” Dr. Mikkelsen says. "This is a very significant advance in the battle to control these aggressive tumors because it could lead to treatment options where none existed previously for patients with recurrent disease.”

Previously Avastin had been used in combination with chemotherapy as a first-line treatment for metastatic colorectal cancer and lung cancer. Because of its demonstrated success rate with these cancers, Avastin currently is being studied worldwide in more than 300 clinical trials for 20 different tumor types.

“With currently approved therapies, the chances of suppressing GBM are poor at less than 10 percent,” says Dr. Mikkelsen. “This type of targeted therapy using Avastin may prove to be the best new hope we have for helping patients with recurrent disease who previously had few options available to them.”

According to the American Cancer Society (ACS), the five-year survival rate for patients with GBM is 3 percent, a figure that has not changed in more than 25 years. The ACS estimates there will be 20,500 new cases of brain cancer and 12,740 brain cancer deaths in 2007.