Avonex® (interferon beta-1a)

Parent company: Biogen Idec

• Taken via weekly intramuscular injections; dosage is 30 mcg (micrograms).
  
  
• The FDA approved Avonex in 1996 for relapsing MS and more recently for individuals with clinically isolated syndrome (CIS).
  
  
• Avonex has been shown to reduce the number of relapses and lesions on MRI, as well as slowing the progression of physical disability. The drug has been shown to be both safe and effective.
  
  
• Interferons appear to reduce inflammation by modulating a favorable balance between cells that increase inflammation and cells that decrease inflammation. They also prevent the transport of damaging lymphocytes into the brain. Lymphocytes are immune-system cells produced to fight infection and disease.
  
  
• The ASSURANCE study includes 15-year data and shows that early suppression of clinical disease activity by Avonex is a marker of treatment response. This is associated with significant long-term benefits for quality of life as compared to patients who had received placebo. These results support other accumulating evidence that short-term responders to Avonex also experience beneficial long-term outcomes.
  
  
• A 10-year analysis of data from the CHAMPS trial, which treated patients with CIS and a positive MRI, showed that although some had characteristics of disease progression, there was evidence of improved disease course with early treatment. These results emphasize the value of early treatment. This effect remained evident in both the CHAMPIONS five- and 10-year extension studies.
  
  
• The Phase III clinical trial (ADVANCE) continues to enroll patients with relapsing-remitting MS (RRMS) to determine the safety and efficacy of BIIB017 (a "PEGylated" version of Avonex), as compared to placebo. PEGylation is a chemical modification of the interferon beta-1a (Avonex) molecule that allows it to be given subcutaneously (under the skin) every two or four weeks, in contrast to the current once-aweek, deeper, intramuscular injection. The goal is to reduce the number of injections and the need for deep injections, while maintaining the positive effect of the drug.
  
  
• Of approximately 1,260 ADVANCE participants, up to 120 will also be enrolled in a sub-study that will involve optical coherence tomography (OCT). This is a rapid, noninvasive, office-based imaging technique that allows objective evaluation of the thickness of the retinal axon (the nerve behind the eye) and nerve layers that atrophy (shrinking due to nerve cell death) in MS. Preliminary evidence supports the use of OCT as an objective tool to monitor the effectiveness of therapy, and it is hoped that OCT may be used as an outcome measure in future studies.

Combination and Comparative Studies:

• The ongoing Phase III CombiRx trial for RRMS is comparing three treatment arms: Avonex with Copaxone, Avonex alone, and Copaxone alone. The study has 1,008 participants; it began in 2005 and is scheduled for completion in July of 2012.