Therapeutic antibodies in multiple sclerosis.

ment of ever more effective drugs for the treatment of MS. The first immunomodulatory agents to benefit from the development mentioned above, interferon(Avonex , Betaferon/Betaseron , Rebif ) and glatiramer acetate (Copaxone ), have been on the market for more than a decade now and are established, safe, yet only mildly effective treatments for MS. They reduce the frequency of new relapses by 30–40%, and their effect on disease progression has remained controversial. Additionally, the necessity to self-inject these drugs in intervals between once daily (Copaxone ) to once weekly (Avonex ), as well as common side effects, such as flu-like symptoms and injection site reactions, limit patient compliance to some degree. Numerous researchers have demonstrated that both interferonand glatiramer acetate exert ‘pleiotropic effects’ on the immune system and the CNS, while essentially leaving the question unanswered as to which of these multiple modes of action are central in treating MS. In contrast, antibodies, in principal a natural component of the immune system, constitute a different kind of therapeutic agents, which can interact with precisely defined targets. This issue of Neurodegenerative Diseases focuses on the role of antibodies as a therapy for MS. The article by Soelberg Sorensen is dedicated to a truly ‘natural’ human antibody preparation: these so-called ‘intravenous immunoglobulins’ are polyclonal human antibodies isolated from the pooled plasma of thousands of human donors. Intravenous immunoglobulins contain the normal humoral immune repertoire and have been Multiple sclerosis (MS) is the most common chronic inflammatory disease of the central nervous system (CNS). MS commonly strikes young adults, exposing them to an uncertain future dimmed by neurological impairment. In spite of immense research efforts in the last decades, there is still no cure for MS. In fact, the cause of MS, leading to variable degrees of inflammation, demyelination and axonal damage in the CNS, is enigmatic. While a strong genetic predisposition is established, environmental factors, possibly infectious agents encountered during childhood and puberty, seem to play an equally important role. Until the early 1990s, immunosuppressive agents like azathioprine were the mainstay of MS treatment. Since then, MS therapy has dramatically changed. New immunobiological findings and pathophysiological concepts as well as advances in biotechnology lead to the identification of a variety of potential therapeutic targets. Improvements in clinical trial design and the development of magnetic resonance imaging have made it possible to objectively quantify the therapeutic benefit of new treatment modalities in a disease as heterogeneous and unpredictable as MS. Also, both society and health insurances have recognized that prevention or delay of neurological impairment in MS patients is important and may be cost effective even in spite of the high prices of modern immunomodulatory drugs, when taking into account the reduced quality of life and the enormous secondary costs due to disability. This in return has made it worthwhile for pharmaceutical companies to invest in the developD i s e a s e s