TNFRSF9 and neoplasm: Bispecific antibodies simultaneously engage T cells, while also binding other immune effectors.45 The earliest success from this strategy has been seen in patients with B-cell leukemia using the bispecific blinatumomab, which binds CD19 on the tumor cell and CD3 on the T cell.46 Bispecific antibodies are being designed to bind co-stimulatory and co-inhibitory molecules, including PD-(L)1, 4-1BB, and LAG-3 among others, which could facilitate direct enhancement of the microenvironment.