MacroGenics Announces Flotetuzumab Publication in Blood Advances

— Role of TP53 abnormalities in immunotherapy response in AML highlighted

ROCKVILLE, MD, Oct. 15, 2020 (GLOBE NEWSWIRE) --  

MacroGenics, Inc. (NASDAQ: MGNX), a clinical-stage biopharmaceutical company focused on discovering and developing innovative monoclonal antibody-based therapeutics for the treatment of cancer, today announced the publication of a manuscript in Blood Advances, a journal of the American Society of Hematology.  This represents the third publication of flotetuzumab data in 2020. Flotetuzumab (also known as MGD006), is an investigational, clinical-stage bispecific DART molecule that recognizes both CD123 on leukemic cells and CD3 on T cells, with the intended result of T-cell-mediated killing of leukemic blasts. This most recent publication reports on the role of flotetuzumab in the immunotherapy of TP53-positive acute myeloid leukemia (AML).

It has previously been shown¹ that an inflammatory (IFN-γ-related) gene expression signature in patients with AML correlated with a lack of response to induction chemotherapy. The same gene signature was shown to be associated with an increased probability of this subset of patients to respond to flotetuzumab. As further described in the article titled “TP53 Abnormalities Correlate with Immune Infiltration and Associate with Response to Flotetuzumab Immunotherapy in AML,” AML with TP53 abnormalities was also associated with immune infiltration in the tumor microenvironment (TME); moreover, patients with TP53 abnormalities derived benefit from flotetuzumab immunotherapy.

“Previous translational studies demonstrated that patients who failed to respond to induction therapy (primary induction failure, or PIF, AML) or those who relapsed within six months of achieving an initial remission (early relapsed, or ER, AML) had an immune-infiltrated TME that not only associated with resistance to standard-of-care chemotherapy regimens, but also with response to flotetuzumab,” said Sergio Rutella, M.D., Ph.D., FRCPath, John van Geest Cancer Research Centre, College of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom. “Included in this PIF/ER AML population are patients harboring TP53 abnormalities, a particularly difficult to treat subset of AML associated with poor prognosis. Interestingly, these patients who responded poorly when treated with standard-of-care chemotherapy regimens appeared to benefit from flotetuzumab therapy.”