Gemtuzumab ozogamicin (GO) is a recombinant humanized immunoglobulin G4 anti-cluster of differentiation (CD)33 monoclonal antibody conjugated to N-acetyl-γ calicheamicin dimethylhydrazide, a naturally potent antibiotic. It has been introduced for the treatment of acute promyelocytic leukemia (APL), since large quantities of CD33 are commonly expressed on the surface of APL cells. The present study reported two cases with prominent disseminated intravascular coagulation (DIC), which was transiently observed following treatment with GO with relapsed/refractory APL. Very limited information exists regarding DIC occurring following GO, and its mechanism remains to be elucidated. In the present study, recombinant human soluble thrombomodulin was used for DIC treatment, and the patients recovered promptly. Since DIC is the most serious adverse event associated with GO treatment, elucidation of its mechanism and establishment of a treatment strategy are warranted.
Keywords: acute promyelocytic leukemia; disseminated intravascular coagulation; gemtuzumab ozogamicin.