Answer
Clinical studies of Avonex (interferon beta-1a) with treatment lasting up to three years suggest that approximately 5% to 8% of patients develop neutralising antibodies.
Sources for this answer
- AVONEX 30 micrograms/0.5 ml solution for injection.Biogen Idec Ltd · emc · SmPC §4.4 Special warnings and precautions for use · Version 34Document updated
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