MacroGenics Inc. (MGNX)

[surf1944]

1:17PM MacroGenics announced presentation of pre-clinical data on DART Molecule Targeting CD123-Positive Leukemic Stem Cells (MGNX) 26.00 -0.01 : The pre-clinical study investigated the ability of a DART, constructed from MacroGenics' proprietary anti-CD3 antibody and an antibody to CD123, to redirect T cells against CD123-positive AML blasts. Investigators demonstrated that the CD3 x CD123 DART, MGD006, binds to both human CD3 and CD123 to mediate target-effector cell aggregation, T-cell activation and proliferation. MGD006 induced a dose-dependent reduction of primary AML blast survival in vitro and in vivo. Notably, a short course of treatment with MGD006 in mice engrafted with an AML patient sample (at an initial T cell : blast ratio of 1:111) induced a near complete elimination ( > 97%) of AML blasts from the peripheral blood and significant clearing from the spleen and bone marrow at 6 weeks post AML cell infusion. The results of this study provide a strong rationale for the clinical development of the MGD006 as a novel molecule for the treatment of patients with AML.