At the European Society of Medical Oncology annual congress in Madrid, a group from the University of Colorado Cancer Center reported results a phase 1 trial of the drug bevacizumab (Avastin) combined with the experimental immunotherapy drug MPDL3280A against a variety of solid tumors. Results were generally mixed, for example with 40 percent of kidney cancer patients responding but only 13 percent of colorectal cancer patients.
“I think our results show that it’s worth continuing this line of study,” says Christopher Lieu, MD, investigator at the CU Cancer Center and assistant professor of Medical Oncology at the University of Colorado School of Medicine. The study’s principal investigator was Gail Eckhardt, MD, co-head of the Division of Medical Oncology and senior associate director of translational and collaborative research at CU Cancer Center.
“In this as in many cases of modern cancer care, the question may not be whether the drug combination works, but in exactly which patients it is most likely to be most effective. It seemed as if some patients saw benefit from the combination. Now the challenge is discovering the markers that allow us to predict which patients will benefit and those who might do better with a different treatment,” Lieu says.
The drug MPDL3280A is representative of a class of drugs currently receiving focused research attention, meant to allow the body’s immune system to target cancer tissue.
“The immune system does a great job of recognizing and neutralizing foreign materials in the body. The problem is, tumors aren’t necessarily foreign – they are grown from the body’s own tissue and so tend to go unrecognized by the immune system. One promising thread of current cancer research is to help the body recognize and target this cancerous tissue,” Lieu says.