Enbrel(R) Is First Therapy Shown To Inhibit Bone And Joint Damage In Psoriatic Arthritis Patients

THOUSAND OAKS, Calif., and RADNOR, PENN., October 25, 2002 -- Results from a study of ENBREL(R)(etanercept), the only fully human TNF receptor, were presented today demonstrating significant inhibition in the progression of structural damage in patients with psoriatic arthritis. These radiographic results were presented as part of an oral presentation at the 66th American College of Rheumatology Annual Scientific Meeting in New Orleans.

"ENBREL is the first therapy to reduce signs and symptoms, and inhibit the progression of bone erosions and joint space narrowing associated with psoriatic arthritis, a disease which has unique and distinct radiographic features not seen in rheumatoid arthritis," said Dr. Peter Ory, department of radiology, University of Washington, and lead investigator of the study. "Patients with psoriatic arthritis often exhibit the painful bone and joint destruction and eventual deformities to fingers, hands and wrists which are associated with disability in this disease."

ENBREL is approved to reduce the signs and symptoms of active arthritis in patients with psoriatic arthritis.

A phase 3 study evaluated 205 patients with active psoriatic arthritis who also had stable psoriasis. Patients first completed a 6-month placebo-controlled blinded portion, then were eligible to enter a 48 week open-label study with ENBREL (25-mg twice-weekly subcutaneous injections). A primary endpoint of the study was determination of radiographic progression in patients treated with ENBREL versus placebo. X-rays of patients' hands and wrists were obtained at baseline, 6 months, upon rollover to active drug and at 12 months.

At one year, there was inhibition of radiographic progression in the ENBREL group (n=101) compared with the placebo group (n=104). The mean change from baseline in total Sharp score (TSS) was a reduction in progression of -0.03 units in the ENBREL group versus an increase in progression of +1.00 units in the placebo group (p=0.0001). The Sharp method uses a 4-point scale to rate joints according to the severity of erosions and degree of joint space narrowing. The erosion and joint space-narrowing subscores are then added to obtain a total radiographic score.

Progression of structural damage was inhibited when measured not only by the TSS, but also by joint erosion scores and joint space narrowing scores. Mean changes from baseline in erosion scores over a year were -0.09 units in patients treated with ENBREL versus +0.66 units in the patients treated with placebo (p=0.0001). Additionally, mean changes in joint space narrowing from baseline over a year were +0.05 units in patients treated with ENBREL, versus +0.34 units in patients treated with placebo (p=0.04).

Adverse events were similar to those reported in previous clinical trials of ENBREL in patients with rheumatoid arthritis. There was no increase in the number of serious adverse events occurring in patients treated with ENBREL compared to those receiving placebo. Only the rate of injection site reactions (ISRs) in patients receiving ENBREL was statistically different compared to placebo (9% with placebo versus 36% with ENBREL in the placebo controlled segment).

ABOUT PSORIATIC ARTHRITIS

Psoriatic arthritis is a chronic inflammatory disease of the joints and connective tissue. The disease combines joint pain and swelling that can lead to crippling debilitation with inflamed and irritated scaly red patches of skin on the body. There are approximately 450,000 patients with psoriatic arthritis in the United States and the disease affects both men and women most commonly between the ages 30 and 50.

ABOUT ENBREL

ENBREL is the only fully human TNF receptor approved for use to reduce the signs and symptoms of active arthritis in patients with psoriatic arthritis, and to reduce the signs and symptoms and inhibit the structural damage in patients with moderately to severely active rheumatoid arthritis (RA). ENBREL is the only biologic therapy approved to treat newly diagnosed RA patients with moderately to severely active disease, and can be used alone.

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 and RA. The binding of ENBREL to TNF renders the bound TNF biologically inactive, resulting in significant reduction in inflammatory activity.

Approved since 1998, ENBREL has been used to treat more than 129,000 patients.

Important Treatment Considerations

SINCE THE PRODUCT WAS FIRST INTRODUCED, SERIOUS INFECTIONS, SOME INVOLVING DEATH, HAVE BEEN REPORTED IN PATIENTS USING ENBREL. MANY OF THESE INFECTIONS OCCURRED IN PATIENTS WHO WERE PRONE TO INFECTIONS, SUCH AS THOSE WITH ADVANCED OR POORLY CONTROLLED DIABETES. RARE CASES OF TUBERCULOSIS HAVE ALSO BEEN REPORTED. ENBREL SHOULD BE DISCONTINUED IN PATIENTS WITH SERIOUS INFECTIONS. DO NOT START ENBREL IF YOU HAVE AN INFECTION OF ANY TYPE OR IF YOU HAVE AN ALLERGY TO ENBREL OR ITS COMPONENTS. ENBREL SHOULD BE USED WITH CAUTION IN PATIENTS PRONE TO INFECTION. CONTACT YOUR PHYSICIAN IF YOU HAVE ANY QUESTIONS ABOUT ENBREL OR INFECTIONS.

There have been reports of 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 ENBRELĀ® (etanercept). There have also been rare reports of serious blood disorders, some involving death. Contact your doctor immediately if you develop symptoms such as persistent fever, bruising, bleeding, or paleness. It is unclear if ENBREL has caused these nervous system or blood disorders. If your doctor confirms serious blood problems, you may need to stop using ENBREL.

The most frequent adverse events in placebo-controlled RA clinical trials involving 349 adults 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 clinical trial of 415 adults with early-stage RA were infections (64%), ISR (34%), and headache (24%). Of these, only the rate of ISR was higher than that of methotrexate. Patients have been observed in clinical trials for over 3 years. The incidence of malignancies has not increased with extended exposure to ENBREL and is similar to the projected background rate.

Adverse events in the psoriatic arthritis trial were similar to those reported in RA clinical trials.

In a study of 69 patients with JRA, infections (62%), headache (19%), abdominal pain (19%), vomiting (13%), and nausea (9%) occurred more frequently than in adults. The types of infections reported in JRA patients were generally mild and consistent with those commonly seen in children. Serious adverse reactions reported rarely were chicken pox (3%), gastroenteritis (3%), serious infection (2%), depression/personality disorder (1%), skin ulcer (1%), inflammation in parts of the upper digestive tract (1%), and diabetes (1%).

Please see full Product Information.

Amgen and Wyeth Pharmaceuticals, a division of Wyeth, (NYSE: WYE), market ENBREL in North America. Other Wyeth affiliates market 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 (NYSE:WYE) 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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Douglas Petkus, 610/902-7336 (media)
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Justin Victoria, 973/660-5340 (investors)

EDITOR'S NOTES:

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Data in this release refer to Abstract # 442 being presented at Plenary Session 1 on Saturday, October 26, 11:00 - 11:15 a.m. CMT in La Nouvelle Orleans Rooms A-C.