Avonex® (interferon beta-1a)

Parent company: Biogen Idec

• Taken via weekly intramuscular injections; dosage is 30 mcg.


• Approved for relapsing forms of MS and for individuals with clinically isolated syndrome (CIS). "CIS" is defined as a single attack (or appearance of one or more symptoms characteristic of MS) with a very high risk of developing MS, when no other diseases are apparent.


• Avonex has been shown to reduce the number of relapses and lesions on MRI, as well as slowing the progression of physical disability.


• Interferons appear to reduce inflammation by modulating a favorable balance between cells that increase inflammation and cells that decrease it.


• An extension of the CHAMPIONS study will continue to evaluate whether immediate initiation of therapy after a first attack continues to delay the development of further attacks and neurologic disability over 10 years.


• The ASSURANCE 15-year follow-up study is evaluating the longer-term impact on the development of disability of early versus delayed initiation of therapy in relapsing-remitting MS (RRMS). Of the 172 participants who completed the original study, about half are still using Avonex, and significantly fewer of these individuals have reached a disability status of 6.0 or greater than those who did not continue treatment. Some patients in the study have used Avonex for up to 17 years. The study is attempting to identify factors that predict a positive response, with no significant clinical disease progression with long-term continued use.


• A new Phase III trial is now recruiting individuals with RRMS to test BIIB017, a "pegylated" interferon beta-1a. Pegylation is a chemical modification of the interferon beta-1a molecule that will allow it to be given subcutaneously (under the skin) every two or four weeks, in contrast to the current once-a-week intramuscular (deeper) injection. This drug was recently granted "Fast Track" designation by the United States' Food and Drug Administration (FDA). This program allows for faster approval of new drugs which are found to be effective in treating serious conditions.


• Combination and Comparative studies: The ongoing three-year, Phase III CombiRx trial for RRMS is comparing three treatment arms: Avonex with Copaxone, Avonex alone, and Copaxone alone.


• The ACT trial evaluated Avonex in combination with methotrexate, intravenous methylprednisolone, or both. Methotrexate is an immunosuppressive drug and methylprednisolone is a steroid that decreases inflammation. Data suggested that adding these medications might be helpful in patients on Avonex who have continuing active disease.


• A study of individuals with RRMS that combines Avonex with Cellcept® is ongoing. Cellcept is an oral immunosuppressant medication used to prevent transplant rejection.