Immunex' Enbrel Launched In USA For Arthritis

Immunex' Enbrel (etanercept) has been approved by the US Food and DrugAdministration for the reduction of symptoms in moderate-to-severe active rheumatoid arthritis in patients who have not responded well to one or more disease-modifying antirheumatic drugs. It has also been approved for use in combination with methotrexate if patients do not gain sufficient benefit from use of methotrexate alone.

Immunex, along with marketing partner Wyeth-Ayerst, launched the product to physicians immediately after the approval was granted. The recommended dose of etanercept for adult patients with RA is 25mg given twice-weekly by subcutaneous injection. The drug is supplied in a carton containing four 25mg dose vials. The average wholesale price of the drug is $11,400 for a year's treatment.

This is the first approval worldwide of the product, which is a dimeric fusion protein consisting of the extracellular ligand-binding portion of the tumor necrosis factor receptor, linked to the Fc portion of human immunoglobin G1. It binds to TNF and blocks its interaction with cell surface TNF receptors. It also modulates biological responses that are induced or regulated by TNF, including expression of adhesion molecules, other cytokines and matrix metalloproteinases.