Biogen has developed a LFA-3/IgG fusion protein,alefacept [BG 9273, LFA 3, LFA 3/CD2, human LFA-3/IgG fusion protein, LFA 3 TIP, AmeviveTM], that is a fusion protein consisting of the first LFA-3 extracellular domain fused to the hinge CH2 and CH3 regions of human IgG1 which is targeted to the CD2 molecule. It has immunomodulatory properties because it recognises the CD2 ligand on the surface of T lymphocytes, thus interfering with the costimulatory role of CD2 in T cell activation. It also appears to block cell adhesion to blood vessel walls and the migration of immune cells into tissue.Psoriasis:Biogen has completed phase III trials of intravenous and intramuscular alefacept as a treatment for patients with chronic plaque psoriasis in the US and Europe. The company submitted simultaneous regulatory filings to the FDA and EMEA in August 2001. Biogen filed a Common Technical Document in Europe and the US under new guidelines implemented in July 2001 at the International Conference on Harmonisation (ICH). In October 2001, Biogen anounced that the FDA and EMEA had both completed initial reviews and had accepted the regulatory filing for full review.Other indications:alefacept was in phase I trials for the treatment ofautoimmune disorders, inflammatory diseases and tissue transplant disorders. Biogen has selected rheumatoid arthritis and scleroderma from this set of indications for further development of alefacept. The drug is currently in phase II clinical trials in rheumatoid arthritis. Biogen stated in June 2001 that a pilot study of Amevive®has been initiated in scleroderma.