Get access

Real-life impact of early interferonβ therapy in relapsing multiple sclerosis

Authors


  • Potential conflicts of interest: M.T. received honoraria for consultancy or speaking from Sanofi-Aventis, Biogen, and Bayer Schering, and research grants from Merck Serono; F.P.2 received honoraria for speaking from Biogen; I.L.S. received honoraria for speaking from Sanofi-Aventis and Biogen, and research grants from Sanofi-Aventis; F.P.3 received honoraria for speaking from Sanofi-Aventis and Merck Serono; A.G. received honoraria for speaking from Bayer Schering, Merck Serono, and research grants from Sanofi-Aventis, Biogen Dompè, and Merck Serono; C.P. received honoraria for consultancy or speaking from Sanofi-Aventis, Biogen, Bayer Schering, and Novartis, and research grants from Merck Serono and Sanofi Aventis; A.L. received honoraria for speaking from Biogen and research grants from Sanofi-Aventis, Merck Serono, Biogen, and Bayer Schering; E.M. received honoraria for speaking from Bayer Schering and research grants from Merck Serono, Sanofi-Aventis, Biogen-Dompè, and Bayer Schering; C.A. received honoraria for consultancy or speaking from Sanofi-Aventis, Biogen-Dompè, Bayer Schering, and Merck Serono; M.C. received honoraria for speaking from Bayer Schering; P.L. received research grants from Sanofi-Aventis, Merck Serono, and Biogen; G.C. received honoraria for consultancy or speaking from Teva Neuroscience Plough Corporation and Merck Serono; M.P.A. received honoraria for speaking from Merck Serono and Biogen, and research grants from Sanofi-Aventis, Merck Serono, Biogen, and Bayer Schering. The other authors declare that they have no conflicts of interest.

Abstract

Objective

Recent findings support greater efficacy of early vs. delayed interferon beta (IFNβ) treatment in patients with a first clinical event suggestive of multiple sclerosis (MS). We aimed to evaluate the effectiveness of early IFNβ treatment in definite relapsing-remitting MS (RRMS) and to assess the optimal time to initiate IFNβ treatment with regard to the greatest benefits on disability progression.

Methods

A cohort of 2,570 IFNβ-treated RRMS patients was prospectively followed for up to 7 years in 15 Italian MS Centers. A Cox proportional hazards regression model adjusted for propensity score (PS) quintiles was used to assess differences between groups of patients with early vs. delayed IFNβ treatment on risk of reaching a 1-point progression in the Expanded Disability Status Scale (EDSS) score, and the EDSS 4.0 and 6.0 milestones. A set of PS-adjusted Cox hazards regression models were calculated according to different times of treatment initiation (within 1 year up to within 5 years from disease onset). A sensitivity analysis was performed to assess the robustness of findings.

Results

The lowest hazard ratios (HRs) for the three PS quintiles–adjusted models were obtained by a cutoff of treatment initiation within 1 year from disease onset. Early treatment significantly reduced the risk of reaching a 1-point progression in EDSS score (HR = 0.63; 95% CI = 0.48–0.85; p < 0.002), and the EDSS 4.0 milestone (HR = 0.56; 95% CI = 0.36–0.90; p = 0.015). Sensitivity analysis showed the bound of significance for unmeasured confounders.

Interpretation

Greater benefits on disability progression may be obtained by an early IFNβ treatment in RRMS. Ann Neurol 2009;66:513–520

Ancillary