Initiation of a phase II trial of lemzoparlimab combined with azacitidine to treat AML/MDS

On May 17, 2021, it was announced that the first patient has been dosed in China in a phase II trial (NCT04202003) combining lemzoparlimab with azacitidine in patients with newly diagnosed acute myeloid leukemia (AML) who are intolerant to intensive chemotherapy or treatment-naïve patients with intermediate- and high-risk myelodysplastic syndromes (MDS). The cohort expansion study will evaluate the safety, tolerability, and clinical efficacy of this promising combination.

CD47 is overexpressed on the surface of leukemic cells and it protects these cells by delivering a "don't eat me" signal to otherwise cell-engulfing macrophages. Lemzoparlimab, is a differentiated anti-CD47 monoclonal antibody that blocks this signal, hence enabling macrophages to attack leukemic cells appropriately. Azacitidine is a well-established chemotherapeutic drug that is often administered in combination with other agents to achieve greater synergistic efficacy in treating hematologic malignancies.

Results from preclinical studies and a phase I clinical trial have demonstrated strong anti-leukemic activity of lemzoparlimab combined with azacitidine, as well as a simultaneous reduction in the inherent binding to normal red blood cells, potentially limiting serious side effects such as severe anemia.