Beta Interferons in Clinically Isolated Syndromes

Abstract – Beta-interferon use in definite multiple sclerosis (MS) has been proven to modify clinical and magnetic resonance imaging outcome. We review and summarize the data of published double-blind, randomized clinical trials to assess, with a meta-analysis the safety and efficacy of beta-interferon on the occurrence of relapses in patients with a first clinical event suggestive of MS. After two years of follow-up, interferon beta decreased the risk of conversion to clinically definite MS 0.51[0.39-0.65], and delayed the time to diagnosis up to 367 days. Side-effects were mild and self limited. Our findings support the efficacy of early treatment with beta-interferon in reducing conversion to clinically defined MS in patients with clinically isolated syndromes. KEY WORDS: interferon, clinically isolated syndromes, multiple sclerosis, immunomodulating therapy.Interferons beta nas sindromes clinicas isoladas: meta-analiseResumo – Ja e suficientemente conhecido que a utilizacao de interferon beta modifica o prognostico clinico e de ressonância magnetica em pacientes com esclerose multipla (EM). Revisamos e sumarizamos os dados dos ensaios clinicos, duplo-cegos, randomizados e controlados com placebos para analisar, atraves de meta-analise, a seguranca e eficacia dos interferons-beta sobre a ocorrencia de recidivas em pacientes com um primeiro evento clinico sugestivo de EM. Apos dois anos de seguimento, os interferons-beta diminuiram o risco de conversao para EM clinicamente definida 0,51[0,39-0,65] e retardaram o tempo para diagnostico em 367 dias. Os efeitos colaterais foram leves e auto limitados. Nossos dados comprovam a eficacia e seguranca do interferon-beta em reduzir a conversao para EM clinicamente definida de pacientes com sindromes clinicas isoladas.PALAVRAS-CHAVE: interferon, sindromes clinicas isoladas, esclerose multipla, terapia imunomoduladora.