Better predicting a tumor’s treatability

Predicting whether a patient’s tumor will shrink in response to a treatment has often been a bit of a guessing game. But this may be changing: Yale researchers have identified a way to determine ahead of time whether a wide range of cancers will respond to MPDL3280A, an experimental drug which blocks the protein PD-L1, a critical “checkpoint” for the body’s immune response to cancer.

Roy S. Herbst, M.D., Ph.D., Ensign Professor of Medicine, and colleagues monitored 175 patients before and after treatment with MPDL3280A. Across patients with a variety of tumors—including melanomas and cancers of the lungs, kidneys, and colon—those with higher levels of PD-L1 in their immune cells at the study’s start responded better to treatment.

The findings, published Nov. 27 in Nature, suggest a way of selecting patients for whom the new drug will work best and highlight the role of immune cells in the drug’s mechanism. The research “could help us design new combination therapies,” Herbst says.