031 Long-term efficacy of ocrelizumab in primary progressive multiple sclerosis: 6.5-study years

Abstract

BackgroundEfficacy/safety of ocrelizumab in primary progressive multiple sclerosis were demonstrated in the ORATORIO (NCT01194570) double-blind period (DBP). Here we assessed the efficacy of switching to, or earlier initiation of, ocrelizumab after 6.5-study years (312 weeks), in the open-label extension (OLE).MethodsDuring the DBP, patients were randomised to ocrelizumab or placebo for ≥120 weeks until a prespecified number of confirmed disability progression (CDP) events occurred. Patients continued blinded treatment until the outcome was ascertained (extended controlled period [ECP]). At OLE initia- tion, patients continued ocrelizumab (OCR-OCR) or switched from placebo to ocrelizumab (PBO-OCR). Time to onset of 24-week-CDP and time-to-wheelchair-confinement (Expanded Disability Status Scale≥7.0) were analysed.ResultsDuring the DBP, ocrelizumab reduced the risk of 24-week-CDP by 25% (p=0.037) vs placebo. At Week 168 (12 weeks after the first patients entered the OLE), the proportion of patients with 24-week-CDP in PBO-OCR and OCR-OCR was 44.7% vs 33.3% (Δ=11.4%; p=0.005), and at Week 312 was 64.8% vs 51.7% (Δ=13.1%; p=0.002), respectively. During DBP+ECP+OLE, risk of wheelchair confinement was 42% lower (p=0.011) and of 24-week-CDP was 28% lower (p=0.002) in OCR-OCR vs PBO-OCR.ConclusionsCompared with PBO-OCR, initiating ocrelizumab 3–5 years earlier significantly reduced the risk of wheelchair confinement and 24-week-CDP.k.schmierer@qmul.ac.uk