CHAPEL HILL - Clinical trials are now underway at the University of North Carolina at Chapel Hill on a promising new drug in the fight against malignant and recurrent brain tumors that have so far proved very difficult to treat.
The tumors studied, glioblastoma multiformae (GBM) and anaplastic astrocytoma, originate in the brain. Of roughly 13,000 malignant brain tumors diagnosed in the United States each year, about 60 percent are GBM and about 20 percent are anaplastics, according to Dr. Matthew Ewend, assistant professor of neurosurgery and section chief of neuro-oncology at the UNC-CH School of Medicine.
"Average survival for patients with glioblastoma multiformae is about one year. It's very malignant and tends to come back at the same site," Ewend explains. "Surgery won't cure it, nor will radiation, although both are of benefit. Chemotherapy to date has had limited success."
Ewend, a member of the UNC Lineberger Comprehensive Cancer Center, says one study is a randomized, phase III clinical trial in which patients with GBM will receive either the new drug SU101 or procarbazine, a standard chemotherapy agent. All participants in this trial will be those whose tumors have returned after previous treatment, including surgery, radiation, and perhaps chemotherapy.
SU101, manufactured by Sugen in Redwood City, Calif., is thought to prevent tumor cell growth by blocking specific molecules on the surface of tumor cells. Laboratory research suggests that these "receptor sites," which attract a hormone-like substance called platelet-derived growth factor (PDGF), appear in increased numbers on tumor cells. Initial clinical studies in 80 patients have shown that nearly half have a positive reaction to the drug.
"It's been suggested that the cells over-express the PDGF receptor and they
stimulate themselves to grow. It is as if they're pouring gas on their own
fire," Ewend says. "By blocking or inhibiting that receptor, we might inhibit
Contact: Lynn Wooten
University of North Carolina School of Medicine