Preclinical Development Of At1412, A Patient Derived Cd9 Antibody That Does Not Induce Thrombosis For Treatment Of B All

Despite recent advances in treatment of B-acute lymphoblastic leukemia (B-ALL) there is still a need for novel targeted therapies. The tetraspanin CD9 is expressed in 60-80% of B-ALL and correlates with adverse prognosis. Recently, the mouse CD9 antibody ALB6 was shown to induce leukemia rejection in NOD/SCID mice. However, clinical development of ALB6 and other CD9-targeting antibodies was hampered by their CD9 mediated induction of platelet aggregation. It is known that CD9 is still expressed on tumor cells after treatment with chemotherapy or blinatumomab (Leung, 2019; Linder, 2016).