Enbrel is a chemically engineered injectable drug designed to help some of the hardest-to-treat sufferers of rheumatoid arthritis. In a study of 234 patients with advanced disease, 59% of those receiving Enbrel for six months significantly improved compared with only 11% of those receiving placebo. When used in combination with the current treatment of choice, methotrexate, 71% of patients improved compared with 27% of patients on methotrexate alone.
Tumor necrosis factor, TNF, is an immune system protein that plays a major role in rheumatoid inflammation. Chemically known as etanercept, Enbrel mimics the receptor for TNF, thereby removing TNF from the patient’s blood before TNF can do damage to the joints. Immunex Corp.’s Enbrel is now on pharmacy shelves.