Neutralizing Antibodies and Multiple Sclerosis in the Era of Disease Modifying Treatments

During an era of rapid changes in Multiple Sclerosis (MS), the early identification of nonresponder patients to therapies is crucial in order to provide them an alternative treatment strategy. The need to identify biomarkers of therapeutic response is a challenge in MS. Biopharmaceutical products approved for MS, such as interferon beta (IFNβ), glatiramer acetate (GA), and natalizumab (NTZ), can lead to the development of antidrug antibodies (ADA), with detrimental effects on their efficacy. In this chapter the evidences of the impact of neutralizing antibodies (NAbs) during IFNβ, GA, and NTZ treatment on clinical and MRI outcomes will be reported. The use of NAbs testing in clinical practice remains a powerful tool in the management of MS therapy.