According to researchers at The University of Texas M. D. Anderson Cancer Center, preliminary study results of a cocktail of bevacizumab (Avastin
Five patients had a partial response in which their lung tumors shrunk by more than 50 percent, and in one of those patients, tumor size was reduced and has stabilized for almost a year, says study leader, Roy S. Herbst, M.D, Ph.D., chief of thoracic medical oncology.
In addition, a significant number of patients have had minor responses (shrinking of tumors by less than 50 percent) as well as stabilization of their disease, he reports.
Herbst collaborated with researchers from the Vanderbilt-Ingram Cancer Center as well as with other investigators in Great Britain and Europe.
"This is a small pilot trial that tests the concept that two agents targeted against different critical cell pathways may be more effective than just one," he says. "This combination clearly appears to be active, showing encouraging anti-tumor activity.
"Lung cancer is a very heterogeneous disease and even with these new molecular therapies we are going to need to take a multi-targeted approach to benefit the maximum number of patients," Herbst says.
He added that even at the highest of several doses tested, the treatments were well tolerated with toxicity that was at most mild to moderate in severity.
"We worried about bleeding, but so far I am pleasantly surprised by how well tolerated this combination can be," Herbst says. "However, this treatment must and can only be given under the scrutiny of the clinical trials setting."
Bevacizumab is a monoclonal antibody that works on the outside of a cancer cell to inhibit vascular endothelial growth factor (VEGF), a protein that plays a critical role in tumor angiogenesis. The small molecule erlotinib is a tablet designed to work inside the cell to block the signaling pathway of the human epidermal growth factor receptor (HER1) pathway, also known as EGFR, which is involved in cancer cell growth.
"This is just the tip of the iceberg. With the recent wave of new molecular therapies approved for cancer we will soon have the ability to rationally identify at-risk patients and combine these agents in our armentarium for maximal effect," says Herbst. "There is still much work to be done, but trials like this are critical to the further success against this deadly disease."
Contact: Laura Sussman or Stephanie Dedeaux, (713) 792-0655