2 The technology


Natalizumab (branded and biosimilar) has a marketing authorisation as a single disease-modifying therapy in highly active relapsing–remitting multiple sclerosis for the following groups.

  • Patients with rapidly evolving severe relapsing–remitting multiple sclerosis defined by 2 or more disabling relapses in 1 year, and 1 or more gadolinium-enhancing lesions on brain MRI or a significant increase in T2 lesion load compared with a previous MRI. This patient group is referred to as the 'RES group'.

  • Patients with high disease activity despite treatment with beta interferon. This group is defined as patients who have failed to respond to a full and adequate course of a beta interferon. Patients should have had at least 1 relapse in the previous year while on therapy, and have at least 9 T2-hyperintensive lesions in cranial MRI or at least 1 gadolinium-enhancing lesion. This patient group is referred to as the 'suboptimal therapy group'.


All antilymphocyte monoclonal antibodies should be given under the supervision of an experienced specialist, in an environment where full resuscitation facilities are immediately available. The use of natalizumab may be associated with infections, urticaria, headache, dizziness, vomiting, nausea, arthralgia, infusion reactions and hypersensitivity reactions. Natalizumab has also been associated with an increased risk of progressive multifocal leukoencephalopathy (PML). For full details of side effects and contraindications, see the summary of product characteristics.


Natalizumab is administered by intravenous infusion; the recommended dose is 300 mg every 28 days. The list price of branded natalizumab (Tysabri, Biogen Idec and Elan Pharma International Ltd) is £1,130 per 300 mg vial (excluding VAT; BNF edition 86). Costs may vary in different settings because of negotiated procurement discounts. Prices paid for branded or biosimilar natalizumab should be no higher than that provided through the branded list price, and should be in line with any future national procurement outcome.