Fig. 4

Time from first EDSS assessment at or after diagnosis to 24-week confirmed EDSS score of ≥ 4 (A) and ≥ 7 (B) Kaplan–Meier survival curve for subgroups of all DMT-naïve PPMS patients ≤ 55 and > 55 years at the time of PPMS diagnosis. Patients were censored at start of any DMT. Patients were considered at-risk until the last assessment visit recorded prior to data cut-off or censored at time of death or at start of any DMT whichever occurred first