Benefit-risk perception of natalizumab therapy in neurologists and a large cohort of multiple sclerosis patients

Background Natalizumab (NAT) is associated with the risk of progressive multifocal leukoencephalopathy (PML). Risk stratification algorithms have been developed, however, without detectable reduction of PML incidence. Objective To evaluate to which extent patients and physicians understand and accept risks associated with NAT treatment. Methods Prospective observational cohort study in German MS centers (n = 73) among NAT-treated MS patients (n = 801) and their neurologists (n = 99). Patients included in this study had mean disease duration of 10.2 years and a mean NAT treatment duration of 24 months. Results More than 90% of patients and physicians voted for shared decision making or an informed choice decision making approach. Patients and physicians perceived a similar threat from MS as serious disease and both overestimated treatment benefits from NAT based on trial data. Men perceived MS more severe than women and perception of seriousness increased with age in both groups and in patients as well with increasing disability. Although patients evaluated their PML risk higher, their risk acceptance was significantly higher than of their neurologists. Risk stratification knowledge was good among neurologists and significantly lower among patients. Conclusion While patients and physicians seem to have realistic risk perception of PML and knowledge of risk stratification concepts, the threat of MS and the perception of treatment benefits may explain the ongoing high acceptance of PML risk.