Brands, Medical Use, Clinical Data
Brands / Synonyms
anti-CD33; Mylotarg; Mylotarg (Wyeth)
Recombinant humanized IgG4, kappa antibody conjugated with a cytotoxic antitumor antibiotic, calicheamicin, isolated from fermentation of a bacterium, Micromonospora echinospora ssp. calichensis. The antibody portion of Mylotarg binds specifically to the CD33 antigen, The anti-CD33 hP67.6 antibody is produced by mammalian cell suspension culture using a myeloma NS0 cell line.
For treatment of acute myeloid leukemia
Used for the treatment of acute myeloid leukemia (AML), mylotarg binds to the CD33 antigen, which is expressed on the surface of leukemic cells in more than 80% of patients with AML. The CD33 antigen is not expressed on pluripotent hematopoietic stem cells or nonhematopoietic cells. This gives mylotarg the selectivity needed to target leukemic cells.
Mechanism of Action
Mylotarg is directed against the CD33 antigen expressed by hematopoietic cells. Binding of the anti-CD33 antibody portion of Mylotarg with the CD33 antigen results in the formation of a complex that is internalized. Upon internalization, the calicheamicin derivative is released inside the lysosomes of the myeloid cell. The released calicheamicin derivative binds to DNA in the minor groove resulting in DNA double strand breaks and cell death.
Biotrnasformation / Drug Metabolism
Most likely removed by opsonization via the reticuloendothelial system.