Biogen Idec receives approval in the European Union for AVONEX(R) PEN(TM)

Biogen Idec (NASDAQ: BIIB) announced today that the European Commission (EC) has granted approval to AVONEX PEN for patients with relapsing multiple sclerosis (MS) and patients who have had a single demyelinating event.

“At Biogen Idec, our commitment to the MS community is unwavering. We strive to meet the needs of all MS patients by harnessing our extensive expertise in neurology and through our commitment to research and innovation,” said Douglas E. Williams, Ph.D., Executive Vice President, Research and Development at Biogen Idec. “For more than 10 years, AVONEX has been the therapy of choice for many MS patients who prefer the convenience of once-weekly injections, along with its proven efficacy and a well-established safety profile. Not only do we think AVONEX PEN makes AVONEX therapy more convenient, it can also help alleviate the anxiety that some MS patients feel when they have to inject their medication.”

AVONEX PEN (AVONEX 30mcg/50ml solution for injection, in pre-filled pen) is the first single-use, once-a-week, fully integrated intramuscular autoinjector available for use with AVONEX treatment in patients with relapsing MS. Biogen Idec designed AVONEX PEN to improve convenience of AVONEX administration by simplifying the injection, helping to reduce injection anxiety and supporting patient independence. It integrates the currently approved AVONEX Prefilled Syringe and utilizes a 25 gauge 16 mm (5/8 inch) needle. This needle was specifically created for AVONEX PEN to be shorter than the needle in the AVONEX Prefilled Syringe.

Additional features of AVONEX PEN include a protective injector shield that conceals the needle prior to injection, automated needle insertion and medication delivery, and a diameter and length designed to stabilize AVONEX PEN during the injection procedure. In addition, AVONEX PEN incorporates a safety lock, which helps prevent injection error, and a display window that confirms complete delivery of the medication. The approval by the EC is based, in part, on a Phase 3b open-label, multicenter study which evaluated the safety and efficacy of AVONEX PEN. The study included patients with MS using AVONEX Prefilled Syringe for at least 12 weeks prior to enrollment. Efficacy of AVONEX PEN was assessed through objective and subjective assessments of key aspects of patients’ use of AVONEX PEN. In the study, the overall success rate for MS patients using AVONEX PEN was 89 percent. In the same study, 94 percent of patients expressed a preference for AVONEX PEN over the AVONEX Prefilled Syringe.

Biogen Idec will begin making the AVONEX PEN available in countries across Europe in the coming weeks.

About AVONEX

AVONEX (interferon beta-1a) is one of the most prescribed treatments for relapsing forms of MS worldwide. It is used worldwide as a treatment for relapsing forms of MS to slow the progression of physical disability and reduce relapses. AVONEX is also approved for patients who have their first clinical episode and have a brain MRI scan consistent with MS.

The most common side effects associated with AVONEX MS treatment are flu-like symptoms, including myalgia, fever, fatigue, headache, chills, nausea, vomiting, pain and asthenia.

AVONEX should be used with caution in patients with depression or other mood disorders and in patients with seizure disorders. AVONEX should not be used by pregnant women. Patients with cardiac disease should be closely monitored. Patients should also be monitored for signs of hepatic injury. Routine periodic blood chemistry and hematology tests are recommended during treatment with AVONEX. Rare cases of anaphylaxis have been reported.

For information regarding the European Summary of Product Characteristics visit http://www.ema.europa.eu/ema. For the complete United States prescribing information, please visit http://www.AVONEX.com.