The role of Gemtuzumab Ozogamicin in the treatment of acute myeloid leukemia patients.

Gemtuzumab Ozogamicin (GO) is an antibody-targeted chemotherapy agent consisting of the humanized murine CD33 antibody (clone P67.6) to which the calicheamicing1 derivative is attached via a hydrolysable bifunctional linker. GO is able to induce apoptosis in vitro in CD33- expressing cells and it has been approved in USA and in Europe as monotherapy for the treatment of elderly patients (older than 60 years) with relapsed acute myeloid leukemia (AML). GO administered as a single agent has resulted in overall response rates of about 30% in previously relapsed adults AML patients (including also with incomplete platelet recovery). Preliminary data indicate a potential role for GO also as a component of induction or consolidation regimens in adults and children. As for adverse events, veno-occlusive syndrome characterizes its tolerability profile, but GO is comparatively well tolerated by most patients.