NEW DATA ON IM ADMINISTRATION SHOWS AMEVIVE® (alefacept) PROVIDES RELIEF FROM PSORIASIS FOR A MEDIAN OF 7 MONTHS

Results of Several Studies on AMEVIVE Presented at International Psoriasis Symposium

Biogen, Inc. (NASDAQ/BGEN) today announced data about the effect of its drug AMEVIVE(R)(alefacept) that show that one 12-week course of AMEVIVE administered via intramuscular (IM) injection provided a median duration of response of 7 months. The response was seen after completion of AMEVIVE therapy in patients with moderate-to-severe psoriasis who achieved a 75% or greater reduction in disease area and severity. This is consistent with response seen with intravenous (IV) AMEVIVE administration. The data were presented at the International Psoriasis Symposium (IPS) in New York City.

“These analyses confirm that AMEVIVE administered via IM injection delivers a significant duration of response, as previously seen with IV administration of the drug. Providing patients with this type of continuing response after treatment gives them relief from their disease and provides an extended holiday from AMEVIVE therapy,” said Dr. Mark Lebwohl, Chairman of Dermatology at the Mt. Sinai School of Medicine in New York City. The data presented this week were based on ongoing analysis of information generated by Phase III clinical trials.

Psoriasis is an autoimmune skin disease that affects more than 4.5 million Americans and 80 million people worldwide. AMEVIVE was approved by the U.S. Food and Drug Administration on January 30, 2003 for the treatment of adults with moderate-to-severe chronic plaque psoriasis who are candidates for systemic therapy or phototherapy. It is the only FDA-approved biologic therapy for the disease.

Patients included in this analysis received 15 mg of AMEVIVE via IM injection once weekly for 12 doses, followed by 12 weeks of observation in the double-blind placebo-controlled study and in an extension study. Patients (n=54) who achieved a 75% or greater reduction in their disease area and severity experienced a median duration of response of 208 days. Duration of response was measured as the length of time a patient maintained a 50% or greater reduction in their disease area and severity after completing one 12-week course of treatment with AMEVIVE. Among patients (n=40) who achieved a Physician Global Assessment of “clear” or “almost clear,” investigators observed a median duration of response of 245 days.

AMEVIVE is available in the U.S. as both IM and IV injections.

Other AMEVIVE data presented at IPS, June 18-22, include:

Amevive in Combination with UVB Therapy
·Data from a pilot study of AMEVIVE given in combination with ultraviolet light B (UVB) therapy in 60 patients with moderate-to-severe psoriasis showed that there were no opportunistic infections. Rash and sore throat were the most frequently reported adverse events in the study.
·This was a small study, and the limited data available suggest that AMEVIVE and UVB therapy together may provide a more rapid onset of effect compared to AMEVIVE monotherapy.

Patients Report Improved Quality of Life
·Data pooled from two Phase III studies examined the effect of AMEVIVE on quality of life among patients who were not candidates for conventional systemic therapy (cyclosporine, methotrexate, oral retinoids) or phototherapy because they failed previous treatments, could not tolerate them or were ineligible to take them due to contraindications.
·Investigators reported a statistically significant improvement in quality of life for these patients after treatment with AMEVIVE, as measured by the Dermatology Life Quality Index (DLQI).

About AMEVIVE
AMEVIVE is indicated for the treatment of moderate-to-severe chronic plaque psoriasis in adults who are candidates for systemic therapy or phototherapy. The treatment is administered via IM or IV injection once per week for 12 doses under the supervision of a physician.

Important Safety Considerations:

The most serious adverse reactions found in clinical trials were: lymphopenia, malignancies, serious infections requiring hospitalization and hypersensitivity.

AMEVIVE reduces lymphocyte counts (also called T-cells). T-cell levels should be measured weekly during the 12-week dosing period. If T-cell levels are too low, physicians will either not initiate, withhold or discontinue treatment.

AMEVIVE is an immunosuppressive agent and may increase the risk of malignancies. Among 1,357 patients who received AMEVIVE in clinical trials, there were 23 reported cutaneous malignancies and 3 lymphomas. AMEVIVE also has the potential to increase the risk of infection and reactivate latent, chronic infections. Nineteen patients in these clinical trials had serious infections, examples of which included postoperative and burn wound infection (4) and pneumonia (3). Hypersensitivity reactions observed in clinical trials included urticaria (5) and angioedema (2). AMEVIVE should be discontinued if the patient develops an anaphylactic reaction. AMEVIVE should not be administered to patients with a history of systemic malignancy, clinically important infection, known hypersensitivity to AMEVIVE or any of its components, or to patients receiving other immunosuppressive agents or phototherapy. Caution should be exercised when considering the use of AMEVIVE in patients with chronic infection, history of recurrent infection or at high risk of malignancy.

Commonly observed adverse events in the first course of placebo-controlled clinical trials with at least a 2% higher incidence in patients treated with AMEVIVE compared to those treated with placebo were: pharyngitis, dizziness, increased cough, nausea, pruritus, myalgia, chills, injection site pain, injection site inflammation and accidental injury.

If a patient becomes pregnant while receiving AMEVIVE or within 8 weeks of finishing AMEVIVE, she should notify her doctor and consider enrolling in the Pregnancy Registry by calling 1-866-AMEVIVE.

For more information about AMEVIVE, including prescribing information and Biogen’s comprehensive support services, call 1-866-AMEVIVE or visit www.amevive.com.

About Biogen
Biogen is the world’s oldest independent biotechnology company and a leader in biologics research, development and manufacturing. A pioneer in leading edge research in immunology, neurobiology and oncology, Biogen brings novel therapies to improve patients’ lives around the world through its global marketing capabilities. For press releases and additional information about the company, please visit www.biogen.com.

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