Abstract
Natalizumab (Tysabri®, formerly known as Antegren®, Elan Pharmaceuticals [Elan; San Francisco, CA, USA] and Biogen Idec [Biogen; Cambridge, MA, USA]) is a humanized monoclonal antibody against α4 integrin, which inhibits leukocyte adhesion and migration into inflamed tissue. The drug has been shown to be more efficacious than placebo in inducing response and maintaining remission in moderate-to-severe Crohn’s disease. There have been reports of progressive multifocal leukoencephalopathy after treatment with natalizumab in Crohn’s disease and multiple sclerosis. It has been otherwise well tolerated, although it is associated with an increased risk of infections, especially influenza and influenza-like illness. The drug is not approved in Europe for the treatment of Crohn’s disease, but it is approved in the USA for the treatment of both multiple sclerosis and moderate-to-severe Crohn’s disease. Owing to the risk of progressive multifocal leukoencephalopathy, it can only be given under the TOUCH program, which is a special restricted distribution program available only to prescribers, infusion centers, pharmacies associated with infusion sites and patients who are enrolled in the program.
Financial & competing interests disclosure
The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.
No writing assistance was utilized in the production of this manuscript.