Natural interferon-beta in chronic progressive multiple sclerosis: results after 2 years of treatment and 2 years of follow up. Ghezzi A, Zaffaroni M, Filippi M, Reganati P, Zibetti A Eur J Neurol. 1995 Apr; 2(2):139-41. PMID: 24283615. Abstract CommentRecommendBookmarkWatch