Improvements in quality of life over 2 years with cladribine tablets in people with relapsing multiple sclerosis: The CLARIFY-MS study

Background: Multiple sclerosis (MS) negatively affects health-related quality of life (HRQoL).Objective: To evaluate HRQoL in people with highly active relapsing MS treated with cladribine tablets (CladT; 3.5 mg/kg cumulative dose over 2 years) in CLARIFY-MS.Methods: Changes in the MS quality of life (MSQoL)-54 scores were analysed using a repeated mixed-effects linear model. Subgroup analyses were performed for participants who were pretreatment-naive and those pretreated with disease-modifying therapies (DMTs) before initiating CladT. Safety and tolerability of CladT were also assessed.Results: MSQoL-54 physical (mean change = 4.86; 95% confidence interval (CI) = 3.18, 6.53) and mental health (4.80; 95% CI = 3.13, 6.46) composite scores (primary endpoints) showed significant improvement at Month 24 versus Baseline (p < 0.0001). Changes in the MSQoL-54 scores were consistent across the pretreatment-naive and DMT-pretreated subgroups. No new severe or opportunistic infections occurred. Most post-baseline lymphopenia events were Grade 1-2 in severity. Transient Grade-3 lymphopenia was observed in 19.7% (95/482) of participants. Grade-4 lymphopenia was not observed.Conclusions: CladT treatment significantly improved the mean MSQoL-54 physical and mental health composite scores over 2 years. CladT efficacy in HRQoL, relapse rates and Expanded Disability Status Scale scores demonstrates its multidimensional effects in MS treatment.