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Tysabri Re-launch Decision: Promise and Perils of Addressing Unmet Needs

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biotechnology management case

Mark J. Ahn & Laura Ueki
Atkinson Graduate School of Management, Willamette University

Summary and key issue/decision: In November 2004, Biogen-Idec and Élan, two well-established biotechnology companies based in Cambridge, Massachusetts and Dublin, Ireland, respectively, were granted permission from the FDA to market their drug, Tysabri (natalizumab) for the treatment of multiple sclerosis (MS). The FDA approval was fast-tracked because of Tysabri’s efficacy in late stage clinical trials, in which the drug, when accompanied with the drug Avonex (beta interferon; Biogen-Idec), reduced probability of relapses in individuals with MS by 54% versus treatment with Avonex alone. Unfortunately, within four months, two cases—one fatal—of the rare and usually terminal disease, progressive multifocal leukoencephalopathy (PML), had been confirmed in patients participating in the trials. Accordingly, in February 2005, Biogen-Idec and Élan voluntarily suspended Tysabri from the market. Because of the drug’s effectiveness and the dearth of other effective treatments for MS, however, there was widespread call for its return. On June 6, 2006, after examining two years worth of clinical trial data and hearing from an advisory committee, the FDA re-approved natalizumab for the treatment of relapsing MS, with the stipulation that prescribers, pharmacies, infusion centers, and patients of the drug are tracked. By the end of the month, the EC approved natalizumab for the European market with their own conditions, and by late July, Biogen-Idec and Élan re-launched Tysabri in the U.S., Germany, Ireland, Sweden and the U.K. This case analyzes the companies’ decision to re-launch their drug despite its association with PML.

Companies/institutions: Biogen-Idec and Élan

Technology: Tysabri (Natalizumab), a humanized monoclonal antibody, inhibitor of the adhesion molecule 4-integrin.

Stage of development at time of issue/decision: The results from two Phase III clinical trials demonstrated that Tysabri use reduced the occurrence of disability progression by 42% (p>0.001), and caused a 68% reduction (p>0.001) in patients’ annual relapse rates compared to placebo. When re-launched, three confirmed cases of PML in patients taking Tysabri had been reported.

Indication/therapeutic area: Multiple sclerosis occurs when inflammatory cells pass through the blood-brain barrier into the central nervous system (CNS) and demyelinate the body’s own nerve cells, impairing their ability to function. Natalizumab works to prevent this by inhibiting the receptors on endothelial cells responsible for allowing inflammatory cells to pass into the CNS.

Geography: US and Europe

Keywords: Tysabri (natalizumab), multiple sclerosis monoclonal antibody, autoimmune disease, progressive multifocal leukoencephalopathy

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