PRELIMINARY STUDY RESULTS OF AMEVIVE® (ALEFACEPT) COMBINED WITH COMMON PSORIASIS TREATMENTS ANNOUNCED AT AMERICAN ACADEMY OF DERMATOLOGY MEETING

Range of Studies Presented at Major Dermatology Conference

Cambridge, MA and San Diego, CA (February 7, 2004) —Preliminary results of an ongoing combination study suggest that adding AMEVIVE ® (alefacept) to common psoriasis treatments, including topical steroids, methotrexate, cyclosporine and phototherapy, improves the treatment outcome for patients with moderate-to-severe chronic plaque psoriasis compared to baseline. Dr. Kenneth Gordon of Loyola University Medical Center, Chicago, Ill., presented results of this study, which was sponsored by Biogen Idec (Nasdaq: BIIB), at the annual meeting of the American Academy of Dermatology in Washington, D.C.

There are approximately 1.5 million Americans with moderate-to-severe psoriasis who require systemic treatments, either alone or in combination, to control their disease. AMEVIVE is a biologic systemic therapy approved for treating adults with moderate-to-severe chronic plaque psoriasis. It works by targeting cells in the immune system that cause psoriasis. This study examined the safety and efficacy of AMEVIVE in combination with other treatments.

“It is encouraging that adding alefacept to conventional treatments improved the burden of disease for a majority of the patients in this study, compared to baseline,” said Dr. Gordon. “So far, combination treatment with alefacept looks promising and I look forward to following these patients’ progress. This study reflects the dermatology practice setting in which physicians typically combine psoriasis treatments to yield the best outcome.”

STUDY RESULTS

At the time of this interim analysis of the open-label study, 201 patients had received at least one dose of AMEVIVE in combination with mid- or high-potency topical steroids (24%), methotrexate (10%), cyclosporine (8%), systemic retinoids (5%) or UVB (4%). An additional 48% of patients in the study received AMEVIVE alone or in combination with low-potency steroids.

Patients in the study had stable disease at baseline while receiving conventional psoriasis therapies. The addition of AMEVIVE appeared to provide improved treatment results for a majority of patients, regardless of baseline severity.

  • After receiving one course of therapy, 86% of patients with severe psoriasis and 67% of patients with moderate-to-severe psoriasis experienced improvement in their Physicians Global Assessment (PGA) by at least one category compared to baseline*.
  • PGA improved by at least two categories in 39% of patients with severe psoriasis and in 38% of patients with moderate-to-severe psoriasis compared to baseline.

*PGA is a 7-point scale that ranges from clear (no signs of psoriasis) to severe (marked plaque elevation and scaling). One category of improvement represents an improvement from “moderate-to-severe” to “moderate,” and so forth.

“In its first year on the market, AMEVIVE has found an important role in the treatment of people with moderate-to-severe psoriasis,” said Burt A. Adelman, M.D., Executive Vice President, Development at Biogen Idec. “We are learning more about how this drug works and believe AMEVIVE offers physicians a flexible, effective tool for managing psoriasis in a real-world practice setting. We look forward to continuing our research in this area.”

The spectrum of adverse events in this study was similar to that observed in Phase 3 studies of AMEVIVE administered alone. Overall, the most common adverse events were headache (12%) and nasopharyngitis (8%). No opportunistic infections were reported. The reduction in T cell counts across the treatment groups has been consistent to that reported in Phase 3 studies.

Additional data presented at the American Academy of Dermatology meeting include reports on:

  • Results from a study on the effect of reduced laboratory monitoring of patients taking AMEVIVE
  • Long-term safety data
  • Preliminary results evaluating the use of AMEVIVE and methotrexate in the treatment of rheumatoid arthritis
  • Preliminary results on the use of AMEVIVE in psoriatic arthritis

ABOUT PSORIASIS

Psoriasis is an autoimmune skin disease in which skin cells multiply ten times faster than the normal rate. The excess cells pile up on the skin’s surface, forming red, raised, scaly plaques that can be painful and disfiguring. Psoriasis affects about 4.5 million U.S. adults.

ABOUT AMEVIVE

AMEVIVE was the first biologic medicine approved in the U.S. for treating moderate-to-severe chronic plaque psoriasis in adults who are candidates for systemic of phototherapies. AMEVIVE may continue to provide some relief after treatment stops. Two large controlled clinical studies have shown that patients with moderate-to-severe chronic plaque psoriasis who respond to AMEVIVE can maintain their response for up to seven months after completing one 12-week course of therapy. These results are from 52 patients in an IV treatment study and from 54 patients in an IM retreatment study.

IMPORTANT SAFETY INFORMATION

AMEVIVE ® reduces the number of T cells, which are one of the body’s ways to fight off cancer and infections. This could increase the possibility of getting cancer and serious infections. Before taking AMEVIVE be sure to tell your doctor if you have had cancer or a serious infection.

Among 1,357 patients treated in clinical studies, 25 patients were diagnosed with 35 cancers. 23 were skin cancers and 3 were cancers of the lymph system. There were 19 patients (1.5%) who experienced serious infections. The most frequent infections were wound infections (4) and pneumonia (3). During and after taking AMEVIVE, if you notice anything unusual about your health or any signs of infection, such as swollen glands, fever or chills, notify your doctor right away.

Because AMEVIVE reduces the number of T cells, you should have a blood test every week during the dosing period to check your T cell levels. If your T cell levels are too low, your physician will not begin treatment with AMEVIVE, will postpone or stop treatment with AMEVIVE.

AMEVIVE should not be taken if you are known to be allergic to AMEVIVE or any of its components, since serious allergic reactions such as hives, with or without swelling of the mouth and tongue, have been seen.

Commonly observed side effects that occurred in clinical studies more frequently with AMEVIVE included: sore throat, dizziness, increased cough, nausea, itching, muscle aches, chills, injection site pain, injection site inflammation, and accidental injury.

If you become pregnant while taking AMEVIVE, or within eight weeks of finishing AMEVIVE, tell your doctor and consider enrolling in the Pregnancy Registry by calling 1-866-AMEVIVE. For full prescribing information, please visit www.amevive.com .

ABOUT BIOGEN IDEC

Biogen Idec creates new standards of care in oncology and immunology. As a global leader in the development, manufacturing, and commercialization of novel therapies, Biogen Idec transforms scientific discoveries into advances in human healthcare. For press releases and additional information about the company, please visit www.biogenidec.com .

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