Overview

For over 10 years, the most common treatment practice for patients with multiple sclerosis (MS) has been what is referred to as an escalation approach, which is thought to minimize risk and allow for surveillance of disease activity. This treatment approach begins with a “platform” disease-modifying drug, such as interferon beta or glatiramer acetate, which is used until it becomes ineffective or intolerable. The patient is then treated with a higher-efficacy drug, such as natalizumab. A less commonly used treatment approach in patients with MS is referred to as induction therapy, in which the patient is treated with a highly effective drug for a specific period of time, followed by either observation or a lower-risk maintenance therapy. The benefits of this treatment approach have not yet been established for patients with MS. Results of a small study of patients with relapsing-remitting MS who were treated with a T-lymphocyte–depleting humanized monoclonal antibody (alemtuzumab) showed a significant reduction in the annual relapse rate (P<0.001) and a clinically meaningful (1.2 Expanded Disability Status Score points) reduction in disability at 6 months after treatment, with further improvement in disability seen up to 36 months. The idea was that early treatment led to suppression of a toxic inflammatory environment for neurons and axons, thus preventing demyelination and long-term axonal degeneration. Treating patients with relapsing-remitting MS during this “early window of opportunity” with highly effective therapies may improve the course of their disease. Biomarkers that are predictive of therapeutic response and disease outcomes are needed to identify patients for whom early treatment with highly effective therapy would be most beneficial.