The success of checkpoint inhibitors such as anti-PD-1 antibodies used in some cancers and experimentally in T-cell exhaustion raises the question if they have a therapeutic role in CVID, with or without recombinant IL-2.75 However, the clinical application of such therapies is unexplored outside the oncology setting and untested in immunodeficient patients. This evidence concerns the gene PDCD1 and common variable immunodeficiency.