Long-term efficacy of cladribine tablets: Results from the MAGNIFY-MS Extension study

BACKGROUND: The Phase IV MAGNIFY-MS Extension study evaluated the long-term efficacy and durability of cladribine tablets (CladT) in participants with highly active relapsing multiple sclerosis (RMS) during treatment-free Years (Y) 3 and 4. METHODS: Data were analysed for all participants and by subgroups (treatment-naïve vs experienced). Time to no evidence of disease activity (NEDA-3) and first confirmed Symbol Digit Modalities Test (SDMT) score change (⩾4/8 point improvement or ⩽4/8 point worsening) were assessed using Kaplan-Meier analysis. SDMT changes were confirmed if sustained across two visits ⩾166 days apart; others were classified as stable. Percentage brain volume change (PBVC) was analysed using the SIENA-XL method. RESULTS: Of 270 MAGNIFY-MS participants, 219 entered MAGNIFY-MS Extension (64.8% female; mean age ± standard deviation: 40.4 ± 9.45 years). NEDA-3 rates were 78.6% (Y3), 79.2% (Y4) and 54.2% (Y3-Y4 combined). At Y4, 83.1% had no T1 gadolinium-enhancing lesions, 67.4% had no active T2 lesions, and the annualised relapse rate was 0.09. Mean annualised PBVC was