In 2012, a major turning point occurred following the publication of encouraging results from clinical trials conducted by Dr. Suzanne Topalian using antibodies that blocked the immunosuppressive programmed death 1 ligand 1 (PD-L1)/programmed death 1 (PD-1) interactions.1,2 Indeed, these trials showed therapeutic efficacies without precedent over a wide range of cancers with possibly the exception of ipilimumab (a CTLA4-specific antibody), developed by Professor James Allison’s team.3 This evidence concerns the gene CTLA4 and cancer.