Why is it so difficult to use gemtuzumab ozogamicin?

摘要

How can we explain the difficulties in finding the best way to use GO? Calicheamicin is a very toxic intercalating agent that is 1000-fold more potent in vitro than doxorubicin. Its conjugation with a monoclonal antibody allows the drug to be delivered directly to leukemic cells and explains its efficacy, but the favorable risk-benefit ratio of the conjugate may be only within a narrow dose range. The use of repetitive low doses is likely a way to enhance the drug's efficacy without increasing toxicity. The ongoing study AML18, from the United Kingdom, is testing a single dose vs 2 doses of 3 mg/m~2 of GO in addition to standard induction.