Did you know?
The Tysabri Observational Program (TOP) — a multinational real-world registry of 6,319 patients with relapsing-remitting MS — has now completed 15 years of prospective follow-up, making it one of the longest continuous observational datasets in multiple sclerosis. The final analysis confirmed that annualized relapse rate reductions were sustained across all 15 years, no new safety signals emerged, and patients who remained on this selective α4-integrin blocker showed a significantly lower probability of converting to non-active secondary progressive MS vs. those who discontinued.

With 15 years of real-world data now available, how does long-term evidence on disability trajectory and SPMS conversion influence your discussions with RRMS patients considering high-efficacy therapy for the first time?