Interim results of an ongoing Phase I, dose escalation study of MGA271 (Fc-optimized humanized anti-B7-H3 monoclonal antibody) in patients with refractory B7-H3-expressing neoplasms or neoplasms whose vasculature expresses B7-H3

Meeting abstracts MGA271 is a humanized IgG1 monoclonal antibody-targeting B7-H3 (CD276), a member of the B7 family. MGA271 has been Fc-engineered to enhance binding to activating FcγR (CD16A), decrease binding to inhibitory FcγR (CD32B), and potentiate ADCC. B7-H3 has limited expression in