The randomized Phase II study at Henry Ford Hospital in Detroit focused on patients with glioblastoma multiforme whose cancer had recurred after first- or second-line therapy. More than one-third who were treated with Avastin alone -- as well as more than half of those treated with Avastin in combination with the chemotherapy drug irinotecan -- lived for six months without further progression of the disease.

"This is very encouraging news," Dr. Tom Mikkelsen, co-director of the Hermelin Brain Tumor Center, said Friday in a release. "Historical estimates suggest that only 15 percent of patients with this aggressive type of brain cancer live without their cancer progressing within six months."

Avastin acts as an anti-angiogenesis agent that chokes off the blood supply to tumors, which in turn inhibits their growth and metastasis, the report said.