A humanized anti-IL-6 receptor antibody(MRA) in RA therapy

Hyperproduction of Interleukin-6(IL-6) is observed in the rheumatoid arthritis(RA) patients and serum level of IL-6 is closely related to disease activity. IL-6 is a pleiotropic cytokine and its hyperfunctions explain most of the clinical symptoms in RA. Since MRA is humanized antibody from a mouse anti-human IL-6 receptor antibody, MRA can be administered repeatedly because of its low antigenesity to human. MRA inhibits IL-6 function by the blocking IL-6 binding to IL-6 receptor, resulting the prevention of development on collagen inducing arthritis(CIA) in cynomolgus monkeys whose IL-6R is cross-reacted with MRA. These evidence suggest that MRA has anti-arthritic effects. Clinical trials of MRA for RA patients have already started, and MRA therapy is effective as well as anti-TNF alpha and anti-IL-1 therapies.