Enbrel (etanercept)

Enbrel was approved in January 2002 for the treatment of psoriatic arthritis. This drug is the first therapy to receive approval to reduce the signs and symptoms of active arthritis in patients with psoriatic arthritis.

Enbrel was initially launched in November 1998, and in addition to psoriatic arthritis, it is also approved for the following indications: reducing the signs and symptoms and inhibiting the progression of structural damage in patients with moderately to severely active rheumatoid arthritis (RA), and for reducing signs and symptoms in patients four years of age and older with moderately to severely active polyarticular-course juvenile rheumatoid arthritis.

Enbrel acts by binding tumor necrosis factor (TNF), an inflammatory cytokine. Tumor necrosis factor plays an important role in both normal immune function, and the cascade of reactions that cause the inflammatory process of RA and psoriatic arthritis. The binding of Enbrel to TNF biologically inactivates the bound TNF, resulting in a significant reduction in inflammatory activity.

Adverse events reported from clinical testing for psoriatic arthritis were similar to those observed in previous trials with rheumatoid arthritis subjects. Adverse events reported in clinical testing of Enbrel include (but are not limited to) the following:

• Injection site reactions
• Upper respiratory infection
• Headache
• Nausea
• Rhinitis
• Dizziness

Since the product was first introduced, serious infections have been reported in patients using Enbrel. Many of these infections occurred in patients who were prone to infections, such as those with advanced or poorly controlled diabetes. Enbrel should be discontinued in patients with serious infections; as with any medication, please contact your physician to discuss whether this product is right for you.

Etanercept binds specifically to tumor necrosis factor (TNF) and blocks its interaction with cell surface TNF receptors. TNF is a naturally occurring cytokine that is involved in normal inflammatory and immune responses. It plays an important role in the inflammatory processes of rheumatoid arthritis (RA), polyarticular-course juvenile rheumatoid arthritis (JRA), and the resulting joint pathology. Elevated levels of TNF are found in the synovial fluid of RA patients and in both the synovium and psoriatic plaques of patients with psoriatic arthritis. (from Enbrel Prescribing Information)

Enbrel is marketed by Immunex and Wyeth-Ayerst Pharmaceuticals.

For more information on Enbrel, please visit www.enbrel.com.