SEATTLE, Nov. 29 /PRNewswire/ -- Data from a clinical study published in the current issue of the New England Journal of Medicine demonstrate that ENBREL(R) (etanercept) can delay progression of structural joint damage in patients with moderately to severely active rheumatoid arthritis (RA), even in patients with the earliest stages of the disease. Patients were included in the study only if they had been diagnosed with active RA within three years, however, on average, patients included in the study had disease for just one year.

The study showed that ENBREL was effective in delaying joint damage in early RA patients, with 72 percent of 207 patients taking ENBREL having no progression of joint erosion measured by x-ray at one year, compared to 60% of 217 patients taking methotrexate.

"This study is important because it showed that ENBREL alone compared favorably to methotrexate, which is the current standard of care," said Barbara Finck, Medical Director at Immunex and one of the lead authors on the New England Journal of Medicine article. "In addition to being effective for reducing signs and symptoms in patients with long-standing moderately to severely active disease, we now know that ENBREL is effective in delaying structural damage in patients with early RA. This is especially important because 70% of RA patients show erosions within 2 years of diagnosis."

ENBREL "ERA" Study

The Early RA, or ERA, trial was a Phase 3 randomized, double-blind, multi-center study that included 632 adults who had RA for less than three years and had never been treated with methotrexate. Patients were randomized to receive either 25 mg or 10 mg of ENBREL by subcutaneous (under the skin) injection or up to 20 mg of methotrexate per week for 12 months. Patients enrolled in this study had RA for a relatively short time (mean of one year), and had active disease (mean tender and swollen joint counts of 30 and 24, respectively, and reported four hours of morning stiffness). All patients had risk factors for rapidly progressive, erosive RA including the presence of rheumatoid factor and/or erosions on baseline x-rays of the hands, wrists and feet.

ABOUT ENBREL

Based on the data from the ERA trial, the U.S. Food and Drug Administration approved ENBREL for reducing signs and symptoms and delaying structural damage in patients with moderately to severely active RA on June 6, 2000 as part of a supplemental biologics license application (sBLA). The FDA originally approved ENBREL on November 2, 1998 to reduce signs and symptoms of moderately to severely active rheumatoid arthritis in patients who have an inadequate response to one or more disease modifying anti-rheumatic drugs (DMARDs). ENBREL is the only TNF inhibitor that can be used with or without methotrexate.

ENBREL acts by binding tumor necrosis factor (TNF). TNF is one of the dominant cytokines or proteins that play an important role in normal immune function and the cascade of reactions that cause the inflammatory process of RA. ENBREL competitively inhibits binding of TNF molecules to the TNF receptor (TNFR) sites. The binding of ENBREL to TNF renders the bound TNF biologically inactive, resulting in significant reduction in inflammatory activity.