MM-111

MM-111 is a bispecific antibody fusion protein targeting the ErbB2/ErbB3 oncogenic unit. MM-111 blocks activation of the PI3K pro-survival pathway. MM-111 binds to the ErbB2 receptor, which localizes the bispecific molecule to ErbB2 over-expressing tumor cells and promotes binding of the anti-ErbB3 arm to the ErbB3 receptor. MM-111 binding to ErbB3 results in inhibition of ErbB3 signaling by blocking the binding of the ErbB3 physiological ligand heregulin. MM-111 can be used for the study of ErbB2 over-expressing breast tumors[1].