An antibody treats almost all refractory autoimmune diseases: Fact and beyond

An antiCD20 monoclonal antibody (rituximab) has been shown to rescue almost all refractory autoimmune diseases. The chimeric antiCD20 antibody is one of the world’s most successfully therapeutic antibodies, with sales of approximately US$5.6 billion in 2009. Rituximab was first approved in 1997 by the US Food and Drug Administration (FDA) for treatment of B cell malignancies, and is now expanded to autoimmune indications, such as lupus nephritis, multiple sclerosis and vasculitis, particularly refractory autoimmune diseases that usually cause fatal outcomes. Autoimmunity is a complex process that involves the interaction of multiple immune cell types. B cells are thought to play a central role in the autoimmune disease serving as precursors to autoantibody-secreting plasma cells. In addition to producing antibodies, B cells are able to present antigen to T cells. Their depletion also results in the removal of antigen-presenting cells, reduced expression of molecules responsible for T cell costimulatory signals, and reduced levels of immune complexes formed between autoreactive antibodies and their antigen. There are certain refractory autoimmune diseases successfully treated by rituximab including antiphospholipid syndrome (APS), thrombotic thrombocytopenic purpura (TTP), antineutrophil cytoplasmic antibody (ANCA) vasculitis, refractory rheumatoid arthritis, refractory juvenile dermatomyositis and refractory idiopathic thrombocytopenic