Inotuzumab ozogamicin (trade name Besponsa) is an antibody-drug conjugate used to treat relapsed or refractory B-cell precursor acute lymphoblastic leukemia (ALL).   The medication consists of the humanized monoclonal antibody against CD22 (inotuzumab), linked to a cytotoxic agent from the class of calicheamicins called ozogamicin.. BESPONSA is used to treat adults with acute lymphoblastic leukaemia. Acute lymphoblastic Acute lymphoblastic leukaemia is a cancer of blood where you have too many white blood cells.. The safety and efficacy of BESPONSA were evaluated in a single-arm, open-label, multicentre Phase 1/2 study (Study 2). Eligible patients were ≥ 18 years of age with relapsed or refractory B-cell precursor ALL.. Page 5: Wyeth Pharmaceuticals LLC, a Subsidiary of Pfizer Inc.: BESPONSA is indicated for the treatment of adults with relapsed or refractory B-cell precursor. . .