Urelumab (BMS-663513) is an IgG4 mAb targeting CD137 and provided clinical responses in B cell malignancies as monotherapy (ORR; 6% in diffuse large B cell lymphoma, 12% in follicular lymphoma, 17% in other B cells lymphomas, respectively) or combination with rituximab (ORR, 35%). This evidence concerns the gene TNFRSF9 and B-cell non-Hodgkin lymphoma.