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 <0.4% in Y4. SDMT scores were 4/8-point stable or improved in 79.0%/88.1% of participants, and 84.5% had no 6-month confirmed disability progression.Conclusion Two years of short-course CladT provided sustained clinical and cognitive benefits, supporting the potential for treatment-free remission in RMS.Clinicaltrials gov Identifier: NCT04783935. Date registered: 3 March, 2021.