FDA Approves ENBREL to Treat Psoriasis; New Convenient Treatment Provides Rapid and Significant Relief of Symptoms| Amgen

FDA Approves ENBREL to Treat Psoriasis; New Convenient Treatment Provides Rapid and Significant Relief of Symptoms

THOUSAND OAKS, Calif. & COLLEGEVILLE, Pa., Apr 30, 2004 -- Amgen Inc. (Nasdaq:AMGN) and Wyeth Pharmaceuticals, a division of Wyeth (NYSE:WYE), today announced that ENBREL(R) (etanercept) has been approved by the U.S. Food and Drug Administration (FDA) 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. The psoriasis indication marks the fifth disease for which ENBREL has received an FDA approval in just over five years.

Psoriasis is a chronic immune disorder in which certain immune cells become overactive and release proteins called cytokines. Tumor necrosis factor (TNF) is one of those cytokines that helps regulate the body's immune response to infection and inflammation. In patients with psoriasis, TNF causes inflammation, which can lead to the formation of painful, often disfiguring psoriasis plaques. As an anti-TNF therapy, ENBREL binds to the over-produced TNF and renders it biologically inactive, which can result in a significant reduction in inflammation.

"Both physicians and patients have expressed a desire for new options to treat psoriasis. ENBREL rapidly cleared psoriasis in many patients and was generally well-tolerated in two large clinical trials," said Laura Hamill, vice president and general manager of Amgen's Inflammation Business Unit. "This approval in psoriasis, coupled with our previous indication in psoriatic arthritis, reinforces our commitment to dermatology and our core aspiration of providing treatments that can dramatically improve people's lives."

The approval was based on data from two Phase 3 studies totaling more than 1,200 adults with plaque psoriasis who were treated with ENBREL for up to 12 months. ENBREL was approved with a step-down dosing regimen of 50 mg administered twice-weekly for three months, followed by a maintenance dose of 50 mg weekly thereafter. ENBREL demonstrated rapid and significant clearing in many patients at this recommended dosing regimen. Patients who are treated with ENBREL require no routine laboratory monitoring specific to ENBREL therapy other than standard medical oversight.

"Dermatologists are already familiar with ENBREL because it is the only approved treatment for psoriatic arthritis. The product is now poised to emerge as a real-world treatment option for psoriasis that can help satisfy the needs of community dermatologists and their patients," explained Gary L. Stiles, M.D., executive vice president and chief medical officer of Wyeth Pharmaceuticals. "Dermatologists have prescribed ENBREL because of its extensive clinical experience and its established safety profile -- ENBREL has 12 years of collective clinical experience in a variety of indications and has been used in more than 234,000 patients worldwide across indications."

"My psoriasis was devastating -- I suffered with the disease for many years. I was in so much pain that I stopped being physically active and gained over 100 pounds," said ENBREL patient, Matt J. "Some of the traditional treatments I'd tried in the past were time consuming, inconvenient and almost worse than the disease itself. Taking ENBREL has been very easy and my skin has cleared and has stayed clear. As a result, I'm not worried about the pain that I once felt from my psoriasis and I'm more outgoing and physically active."

Study Results

In a Phase 3 study, nearly half (46 percent) of patients receiving 50 mg twice-weekly of ENBREL achieved the primary endpoint of a 75 percent or greater improvement in the Psoriasis Area Severity Index (also known as PASI 75) at three months. These patients were "stepped down" to half the dose and then continued treatment for an additional three months. At six months, the percentage of patients achieving a PASI 75 response was maintained following dose reduction.

"Psoriasis can be a chronic, disabling disease requiring continuous treatment. ENBREL was shown to provide rapid and significant relief of psoriasis in many patients," said Alice Gottlieb, M.D., Ph.D., director of the Clinical Research Center at the University of Medicine and Dentistry of the New Jersey-Robert Wood Johnson Medical School. "Additionally, in one clinical trial, patients who stopped treatment did so without experiencing disease flare or rebound. The trial also demonstrated, that upon retreatment with ENBREL the overall response rates were similar to those seen after initial treatment."

ENBREL was generally well-tolerated in both Phase 3 studies. Adverse events were similar to those reported in previous clinical trials in other indications. The most common adverse events in the ENBREL group when compared to placebo were injection site reactions.


An estimated 4.5 million people in the United States suffer from psoriasis and 1.5 million have moderate to severe plaque psoriasis. The disease is characterized by chronic inflammation of the skin. This inflammation helps drive the formation of red, itchy skin plaques that are often painful and disfiguring. Tumor necrosis factor (TNF) is found at increased levels in psoriatic plaques and plays a critical role in their formation and continued existence.


ENBREL is the only fully human TNF receptor approved to reduce signs and symptoms, improve physical function, and inhibit the progression of structural damage in patients with moderately to severely active rheumatoid arthritis (RA), and to reduce the signs and symptoms and inhibit the progression of structural damage of active arthritis in patients with psoriatic arthritis. ENBREL is the only biologic therapy approved for first-line treatment of RA patients, and can be used alone or in combination with methotrexate. 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 234,000 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 that causes 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 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, hemophilia, oncology and vaccines. 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 non-prescription 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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Andrea Rothschild, 805-447-4587 (media)
Cary Rosansky, 805-447-1060 (investors)
Wyeth Pharmaceuticals
Jenifer Antonacci, 484-865-5220 (media)
Justin Victoria, 973-660-5340 (investors)