PD-L1 inhibition with MPDL3280A for solid tumors.

Cancer immunotherapy has become a popular anticancer approach, with the goal of stimulating immune responses against tumor cells. Recent evidence has demonstrated that the use of monoclonal antibodies targeting the programmed death ligand-1 (PD-L1)/programmed death-1 (PD-1) checkpoint pathway can result in well-tolerated clinical responses in a wide variety of tumor types. This review summarizes the safety, clinical activity and biomarker data for the anti-PD-L1 antibody, MPDL3280A, from a phase Ia multicenter, dose-escalation and -expansion trial. The data to date suggest that MPDL3280A is most effective in patients with pre-existing immunity suppressed by PD-L1 and reinvigorated upon antibody treatment.