RES234M1.1

RES234M1.1 is a preclinical-stage bispecific DART (Dual-Affinity Re-Targeting) molecule developed by MacroGenics. It is an Fc-bearing version of flotetuzumab, designed to target CD123 (IL-3 receptor alpha chain) on leukemic cells and CD3 on T cells. Unlike the parent molecule flotetuzumab, which lacks an Fc domain and requires continuous infusion, RES234M1.1 incorporates a human IgG1 Fc domain with "ala-ala" (L234A/L235A) mutations. These mutations extend the molecule's circulating half-life via the neonatal Fc receptor (FcRn) while impairing binding to Fc-gamma receptors and complement, thereby reducing effector-mediated toxicity. In research settings, RES234M1.1 serves as a high-affinity CD3-binding control to evaluate the efficacy and safety of next-generation molecules like MGD024 in models of acute myeloid leukemia (AML).

Other names

Fc-bearing flotetuzumabIgG1-ala-ala Fc-bearing flotetuzumabIgG-1-ala-ala Fc-bearing flotetuzumabIgG 1-ala-ala Fc-bearing flotetuzumab