New Two-Year Data Show That Most Rheumatoid Arthritis Patients Treated with ENBREL Plus Methotrexate Had No Progression of Joint Damage

Additional Data Demonstrated that Patients Treated with ENBREL

Plus Methotrexate had Greater Improvement in Physical Function Scores

After Two Years Compared to Methotrexate Alone

THOUSAND OAKS, Calif. & COLLEGEVILLE, Pa.--(BUSINESS WIRE)--Oct. 18, 2004-- Nearly three quarters (74.2 percent) of rheumatoid arthritis (RA) patients treated with ENBREL(R) (etanercept) plus methotrexate combination therapy experienced no progression of joint damage over a continuous two-year span. These new two-year results from the ongoing TEMPO (Trial of Etanercept and Methotrexate with Radiographic Patient Outcomes) study were presented today at the American College of Rheumatology's Annual Scientific Meeting in San Antonio, Texas.

"It is remarkable to see that a large majority of patients experienced no progression of joint damage while on ENBREL and methotrexate combination therapy. Moreover, the patients taking the combination therapy had better mean x-ray scores as a group after two years compared to baseline," said Desiree van der Heijde, M.D., professor of rheumatology, University of Maastricht in the Netherlands. "These data confirm the one year results and underscore the importance of aggressive treatment to help prevent long-term disability."

At two years, 74.2 percent of patients taking ENBREL and methotrexate combination therapy had no progression of joint damage as assessed by Total Sharp Scores (TSS). These validated scores are calculated by using x-ray measurements to assess joint damage. No progression is defined as a mean change from baseline in TSS less than or equal to 0. By comparison, 65.5 percent and 59.2 percent of ENBREL monotherapy and methotrexate monotherapy-treated patients, respectively, had no radiographic progression of joint damage at two years.

Further, data presented at ACR show that improvement in physical function scores were higher for the ENBREL combination group than those taking either therapy alone. Patients treated with ENBREL combination therapy experienced a 56 percent mean improvement in Health Assessment Questionnaire (HAQ) scores from baseline, compared to 39 percent mean improvement in patients treated with ENBREL alone and 36 percent mean improvement in patients treated with methotrexate alone. HAQ scores measure a patient's ability to perform activities of daily living such as dressing, walking and grooming.

The ENBREL TEMPO study randomized 686 patients with RA, of which 622 were included in the two-year radiographic analysis. Patients received either ENBREL (25 mg twice weekly), methotrexate (up to 20 mg once weekly), or ENBREL (25 mg twice weekly) plus methotrexate once weekly. Patients in the ENBREL TEMPO trial had active RA and an inadequate response to at least one disease-modifying antirheumatic drug (DMARD) other than methotrexate. The primary radiographic endpoint was the change from baseline in the van der Heijde-modified TSS at one year. Secondary radiographic endpoints included changes in total erosions, changes in total joint space narrowing, number of eroded joints and percent of patients with no radiographic progression.

Treatment with ENBREL therapy was generally well-tolerated.
ABOUT RA

More than two million Americans suffer from RA, which can cause stiffness, swelling and limitation in the motion and function of multiple joints. If RA is left untreated, patients can become disabled from joint damage caused by the disease, limiting their ability to function.

ABOUT ENBREL

ENBREL is the only fully human TNF receptor approved to reduce signs and symptoms, induce major clinical response, improve physical function, and inhibit the progression of structural damage in patients with moderately to severely active rheumatoid arthritis (RA). ENBREL is approved for first-line treatment of RA patients and can be used alone or in combination with methotrexate.

ENBREL is also indicated to reduce the signs and symptoms and inhibit the progression of structural damage of active arthritis in patients with psoriatic arthritis. It is approved to reduce the signs and symptoms of moderately to severely active polyarticular-course juvenile rheumatoid arthritis (JRA) in patients who have had an inadequate response to one or more disease-modifying antirheumatic drugs (DMARDs). It is also the first biologic approved to treat the signs and symptoms in patients with active ankylosing spondylitis (AS). ENBREL is indicated for the treatment of adult patients (18 years or older) with chronic moderate-to-severe plaque psoriasis who are candidates for systemic therapy or phototherapy.

ENBREL has been used by more than 250,000 patients worldwide across indications.

ENBREL acts by binding TNF, one of the dominant inflammatory cytokines or regulatory proteins that play an important role in both normal immune function and the cascade of reactions involved in the inflammatory process of RA, JRA, psoriasis, psoriatic arthritis and AS. The binding of ENBREL to TNF renders the bound TNF biologically inactive, resulting in significant reduction in inflammatory activity.

Since the product was first introduced, the following have been reported in patients using ENBREL:

Amgen Inc. and Wyeth Pharmaceuticals, a division of Wyeth, market ENBREL in North America. Wyeth markets ENBREL outside of North America. Immunex Corporation, a wholly owned subsidiary of Amgen, manufactures ENBREL. Additional information about ENBREL, including full Prescribing Information, can be found on the Web site sponsored by the companies at www.enbrel.com or by calling toll free 888-4ENBREL (888-436-2735).

Amgen is a global biotechnology company that discovers, develops, manufactures and markets important human therapeutics based on advances in cellular and molecular biology. Wyeth Pharmaceuticals, a division of Wyeth, has leading products in the areas of women's health care, cardiovascular disease, central nervous system, inflammation, transplantation, hemophilia, oncology, vaccines and nutritional products. Wyeth is one of the world's largest research-driven pharmaceutical and health care products companies. It is a leader in the discovery, development, manufacturing, and marketing of pharmaceuticals, vaccines, biotechnology products and nonprescription medicines that improve the quality of life for people worldwide. The Company's major divisions include Wyeth Pharmaceuticals, Wyeth Consumer Healthcare, and Fort Dodge Animal Health.

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SOURCE: Amgen