Real-world treatment outcomes and safety of natalizumab in Finnish multiple sclerosis patients.

Objectives: The primary objective was to evaluate long-term treatment persistence and safety of natalizumab in Finnish multiple sclerosis patients. The secondary objectives were to assess patient characteristics, use of natalizumab-related safety protocol, and treatment persistence in patients with different anti-John Cunningham virus antibody statuses (John Cunningham virus status).

Materials & Methods: All adult multiple sclerosis patients in the Finnish multiple sclerosis register who started natalizumab between 1/2006 and 12/2018 were included in this study and followed retrospectively until treatment discontinuation or end of follow-up (12/2019).