Enbrel is First Biologic to Receive FDA Approval for the Treatment of Ankylosing Spondylitis| Amgen

Enbrel is First Biologic to Receive FDA Approval for the Treatment of Ankylosing Spondylitis


THOUSAND OAKS, Calif., and COLLEGEVILLE, Pa., July 24, 2003 - Amgen (NASDAQ: AMGN) and Wyeth Pharmaceuticals, a division of Wyeth (NYSE: WYE), today announced that ENBREL  (etanercept) (25 mg twice weekly) is the first biologic to be approved by the U.S. Food and Drug Administration (FDA) to reduce the signs and symptoms in patients with active ankylosing spondylitis (AS). Ankylosing spondylitis marks the fourth indication for ENBREL. The FDA's decision follows an expedited review.

"The approval of ENBREL for the treatment of AS is truly exciting, offering many patients significant relief of symptoms such as back pain, morning stiffness and fatigue as rapidly as two weeks after initiation of therapy. Also, for the first time, we see improvement in spinal mobility which is a debilitating symptom of the disease," said Kevin Young, vice president of Amgen's Inflammation Business Unit.

Ankylosing spondylitis, which affects approximately 350,000 people in the United States, is a painful, and potentially progressive inflammatory disease affecting joints and ligaments that normally allow a person's back to move and flex. The disease most often occurs in the lower back but can affect the upper spine, chest, and neck. The spine can fuse, causing loss of motion and a permanent stooped-over posture. Ankylosing spondylitis may also involve other joints, such as the hips, shoulders, knees, and ankles. Unlike some other forms of arthritis, AS frequently strikes between the ages of 16 and 30. It tends to affect more men than women.

"Ankylosing spondylitis is widely underdiagnosed and in its most severe forms, can be devastating to a person's ability to function at home or work," said Jane Bruckel, RN, executive director of the Spondylitis Association of America.

"We are pleased to now be able to offer ENBREL to physicians and patients battling ankylosing spondylitis," said Dr. Victoria Kusiak, vice president of global medical affairs and North American medical director of Wyeth Pharmaceuticals. "ENBREL has a history of proven efficacy and tolerability which will be important to physicians introducing the therapy to a new group of patients."

In a pivotal Phase 3 study (n=277), 60 percent of patients treated with ENBREL (n=138) achieved a 20 percent improvement in the Assessment in Ankylosing Spondylitis Response Criteria (ASAS 20), a composite measure that includes back pain, morning stiffness, inflammation and physical function, compared with 27 percent of patients receiving placebo after 12 weeks. At 24 weeks, 58 percent of patients treated with ENBREL achieved this significant reduction compared with 23 percent of the placebo patients.

Adverse events were similar to those reported in previous clinical trials of ENBREL, with injection site reactions occurring more frequently than in the placebo group. The most frequent adverse events in placebo-controlled rheumatoid arthritis (RA) clinical trials (n=349) were injection site reactions (ISR) (37%), infections (35%), and headache (17%). Only the rate of ISR was higher than that of placebo. The most frequent adverse events in a methotrexate-controlled trial (n=415) were infections (64%), ISR (34%), and headache (24%). Only the rate of ISR was higher than that of methotrexate.


ENBREL is the only fully human anti-TNF receptor approved to reduce the signs and symptoms and inhibit the structural damage in patients with moderately to severely active RA, and to reduce the signs and symptoms of active arthritis in patients with psoriatic arthritis. ENBREL can be used in combination or alone. It is also 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 disease-modifying medicines.

Physicians have become familiar with the benefits and proven long-term tolerability profile of ENBREL. It has been used to treat over 180,000 patients worldwide across all indications since becoming commercially available nearly five years ago.

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 psoriatic arthritis, RA 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:

• Serious Infections

- Many occurred in people prone to infection, such as those with advanced or poorly controlled diabetes

- Some serious infections were fatal

- Rare cases of tuberculosis

• What to do/Not do

- Do not start ENBREL if you have an infection or are allergic to ENBREL or its components

- Tell your doctor if you are prone to infection

- Stop ENBREL if a serious infection occurs

- Contact your doctor if you have questions about ENBREL or develop an infection

• Serious nervous system disorders such as multiple sclerosis, seizures, or inflammation of the nerves of the eyes.

- Tell your doctor if you have ever had any of these disorders or if you develop them after starting ENBREL.

• Rare reports of serious blood disorders (some fatal)

- Contact your doctor immediately if you develop symptoms such as persistent fever, bruising, bleeding, or paleness

• The incidence of cancer has not increased with extended exposure to ENBREL and is similar to the expected rate.

• ENBREL can also cause injection site reactions.

• In a medical study of patients with JRA, infections, headaches, abdominal pain, vomiting, and nausea occurred more frequently than in adults.

− The kinds of infections reported were generally mild and similar to those usually seen in children

− Other serious adverse reactions were reported rarely, including serious infections (2%) and depression/personality disorder (1%)

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 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.

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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