014 Long-term effectiveness of natalizumab for RRMS: UK and global interim results from TYSABRI observational program

Abstract

IntroductionThe TYSABRI Observational Program (TOP) is a large, ongoing observational study in relapsing- remitting multiple sclerosis (RRMS) patients treated with natalizumab. Country-specific data on relapse and disability outcomes, alongside global data, can provide information on natalizumab’s effectiveness in local practice.MethodsAnnualised relapse rate (ARR) and cumulative probability of 24-week confirmed disability worsening (CDW; increase in Expanded Disability Status Scale [EDSS] score ≥1.5 from a baseline of 0.0,≥1.0 from a baseline between 1.0–5.5, or ≥0.5 from a baseline of ≥6.0) and improvement (CDI; decrease≥1.0 from a baseline EDSS score ≥2.0) were analysed in TOP UK (n=134) and global (N=6295) cohorts using data from July 2007 to November 2018. Updated data (as of November 2019) will be presented.ResultsARR decreased in UK patients from 2.21 in the year before initiation to 0.19 on natalizumab (P<0.0001), consistent with a global decrease from 2.00 to 0.21 (P<0.0001). At 7 years, probabilities of CDW and CDI were, respectively, 26.2% and 35.3% in UK patients and 27.9% and 32.1% globally.ConclusionsThese TOP UK results show disease control that is generally consistent with global TOP results, supporting natalizumab’s long-term effectiveness in real-world settings.SupportBiogen. Disclosures: Included on the poster.richard.nicholas@btinternet.com