Long-term natalizumab treatment is associated with sustained improvements in quality of life in patients with multiple sclerosis

BACKGROUND Multiple sclerosis (MS) patients experience lower health-related quality of life (HRQoL) than the general population. In clinical trials, natalizumab significantly improved HRQoL and reduced relapse rates and disability progression in patients with relapsing MS. In a 1-year analysis of patients included in the current study, HRQoL improvement occurred within 3 months of natalizumab initiation and continued for 1 year thereafter. However, natalizumab's long-term efficacy in improving HRQoL has not been studied. METHODS In this longitudinal, observational, single-arm US study, HRQoL and treatment satisfaction were evaluated in MS patients receiving intravenous natalizumab 300 mg every 4 weeks in clinical settings. Patients completed surveys at baseline and every 6 months for 3 years and reported the following measures: Short Form-12 Version 2 (SF-12v2), Multiple Sclerosis Impact Scale (MSIS-29), and Treatment Satisfaction Questionnaire for Medication. RESULTS In this study, 120 patients completed ≥3 years of natalizumab treatment. Significant HRQoL improvements were evident from baseline to year 3 by increases in SF-12v2 Physical Component Summary (PCS) and Mental Component Summary scores (P<0.01) and decreases in MSIS-29 physical and psychological scores (P<0.0001). Patients with less physical disability (baseline Disease Steps [DS] 0-2) had significant improvement from baseline to year 3 in SF-12v2 PCS (P<0.05) and MSIS-29 physical scores (P<0.05). Physical HRQoL outcomes in patients with baseline DS 3-6 remained stable over 3 years. Treatment satisfaction increased significantly from baseline to year 1 (P<0.0001) and was maintained in the following 2 years. CONCLUSION Patients reported physical and psychological HRQoL improvements over 3 years of natalizumab treatment, supporting the long-term efficacy of natalizumab in real-world settings. Lower baseline disease activity and earlier treatment were related to better outcomes, indicating the importance of starting natalizumab early in the disease course. Treatment satisfaction increased after natalizumab initiation and remained high over 3 years of treatment.