CD19 and B-cell non-Hodgkin lymphoma: Most of the BsAbs under development treating R/R indolent and aggressive B-cell lymphomas engage the CD3 invariant subunit of the T-cell receptor complex, and CD20 (CD20 × CD3 BsAb) or CD19 (CD19 × CD3 BsAb) on lymphoma cells (Table 3).