Related Experiment Video
Updated: Aug 4, 2025

A Method of Trigonometric Modelling of Seasonal Variation Demonstrated with Multiple Sclerosis Relapse Data
Published on: December 9, 2015
Long-term follow-up of patients with relapsing multiple sclerosis from the CLARITY/CLARITY Extension cohort of
Gavin Giovannoni1, Alexey Boyko2, Jorge Correale3
1Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
Background:
CLASSIC-MS evaluated the long-term efficacy of cladribine tablets in patients with relapsing multiple sclerosis.
Objective:
Report long-term mobility and disability beyond treatment courses received in CLARITY/CLARITY Extension.
Methods:
This analysis represents CLASSIC-MS patients who participated in CLARITY with/without participation in CLARITY Extension, and received ⩾1 course of cladribine tablets or placebo (N = 435). Primary objective includes evaluation of long-term mobility (no wheelchair use in the 3 months prior to first visit in CLASSIC-MS and not bedridden at any time since last parent study dose (LPSD), i.e. Expanded Disability Status Scale (EDSS) score <7). Secondary objective includes long-term disability status (no use of an ambulatory device (EDSS < 6) at any time since LPSD).
Results:
At CLASSIC-MS baseline, mean ± standard deviation EDSS score was 3.9 ± 2.1 and the median time since LPSD was 10.9 (range = 9.3-14.9) years. Cladribine tablets-exposed population: 90.6% (N = 394), including 160 patients who received a cumulative dose of 3.5 mg/kg over 2 years. Patients not using a wheelchair and not bedridden: exposed, 90.0%; unexposed, 77.8%. Patients with no use of an ambulatory device: exposed, 81.2%; unexposed, 75.6%.
Conclusion:
With a median 10.9 years' follow-up after CLARITY/CLARITY Extension, findings suggest the sustained long-term mobility and disability benefits of cladribine tablets.
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