A fusion protein, cytotoxic T-lymphocyte–associated antigen 4–IgG1 (CTLA4Ig), is the first in a new class of drugs known as costimulation blockers being evaluated for the treatment of rheumatoid arthritis. Preliminary study results indicate CTLA4Ig may be effective for the treatment of RA. Read the abstract in the New England Journal of Medicine.

UPDATE: In December 2005, Orencia, generic drug name abatacept, was approved by the FDA. Orencia is the first T-cell co-stimulation modulator approved for the treatment of rheumatoid arthritis. Orencia, a fully human soluble fusion protein, works by selectively modulating a co-stimulatory signal which is required for full T-cell activation.

Related Resources:

• More About Orencia (abatacept)
• Orencia (Abatacept) For Rheumatoid Arthritis
• What's the Difference Between Orencia and Other Biologic Drugs?