Natalizumab for Multiple Sclerosis

Ransohoff RM. NEJM 2007; 356:2622-9. Clinical Therapeutics. Review article. Introduction cites that 50 % of patients reach the following disability milestones at the following times: loss of employment, 10 years after diagnosis; use of assistive devices to walk (15 years); inability to walk (25 years).The cost of care is about $47,500 per patient per year. Natalizumab contains humanized MAB's against leukocyte alpha 4 integrins, which, together with Beta chain, comprise heterodimeric glycoprotein responsible for trafficking leukocyte entry in to the CNS. In trial one, 942 patients were randomized to infusion v. placebo. Natalizumab decreased cumulative probability of sustained disability progression from 29 to 17 % (p<0.001, NTT=9), and reduced number of enhancing lesions on MRI at year 2 by 92 %. The second study, N was added to interferon beta (or not) in 1171 patients, reduced sustained disability from 29 to 23 %, NTT = 17, increased relapse free patients from 37 to 61 %, NTT=5, 89 % reduction in enhancing lesions. The review article indicates the necessity of a three month hiatus from immunosuppressant medication before starting the drug, and ensuring the diagnosis of MS is secure. TOUCH program mandates assessment of the patient at 4,7,13 and every 6 months therafter.