Ibritumomab-Tiuxetan

  • CAS Number: 206181-63-7

Ibritumomab tiuxetan ( Zevalin ® trade name; authorization holders in the EU: Bayer Schering) is a conjugated monoclonal antibody which is used as a drug in the radioimmunotherapy of various malignant lymphomas of B- cells ( lymphoma ).

Construction

It is an immunoconjugate that is a combination of an antibody with another substance which the above through a stable covalent bond between the thiourea

  • Monoclonal antibody Ibritumomab ( a recombinant murine monoclonal IgG1κ antibody which is specifically directed against the B cell antigen, CD20 ) and the
  • Chelator ( complexing ) tiuxetan.

Production

The antibody is produced by genetically engineered Chinese hamster ovary cells ( CHO cells Chinese Hamster Ovary) and consists of two heavy γ - chain 445 amino acids, each with κ and two light chains, each with 213 amino acids.

Operation

The chelator brings a binding site of high affinity to a 90Yttrium. 90Y is a β - emitter. The antibody search the target ( B cells ) and thus leads the bound to the chelator radioactive yttrium closer to the B cell, which it directly and their immediate environment exposes specific and over a longer period of high-energy radioactive radiation, but this other, distant cells protects. In addition, the antibody alone has therapeutic effect (see also rituximab). However, it will be all the cells that contain the antigen on the surface attacked, and normal B cells. Spared, however, be B- cell precursors, so as hoped-for outcome after radical killing fully developed B- cells, all cancer cells have died and which are essential for disease resistance B cells can be re- formed from the precursors.

History

Ibritumomab tiuxetan (now Biogen Idec ) developed by Idec Pharmaceutical. The first registered in 2002 in the United States. In the EU ibritumomab tiuxetan was approved in 2004. Authorization holder and distributor for the EU is Bayer Schering. The U.S. company Cell Therapeutics acquired the U.S. rights in 2007, Biogen Idec. The drug is still manufactured at Biogen Idec.

CAS registry number Anatomical Therapeutic Chemical Classification System DrugBank Active ingredient Digital Object Identifier
406476
de