Checkpoint Inhibitors Boost Power of Antibody–Drug Conjugate

The antibody-drug conjugate T-DM1 spurs immune cells to infiltrate HER2-positive breast tumors in patients. Treating mice that carry breast tumors with T-DM1 improves survival, but the tumors suppress the infiltrating lymphocytes. Combining T-DM1 with checkpoint inhibitors that block CTLA-4 and PD-1 overcomes this effect, eliminating breast tumors from 95% of the mice.