Efficacy and Safety Study of Peginterferon Beta-1a in Participants With Relapsing Multiple Sclerosis (ADVANCE)

Primary Outcome Measures:

• Annualized Relapse Rate (ARR) at 1 Year [ Time Frame: 1 Year ]
  A relapse is defined as new or recurrent neurologic symptoms not associated with fever or infection, lasting for at least 24 hours, and accompanied by new objective neurologic findings. Only relapses confirmed by an independent neurology evaluation committee (INEC) are included in the analysis. Data after participants switched to alternative multiple sclerosis (MS) medications are excluded. Data were analyzed using negative binomial regression, adjusted for baseline Expanded Disability Status Scale (EDSS) score (< 4 versus ≥ 4), baseline age (< 40 versus ≥ 40 years), and baseline relapse rate (number of relapses in 3 years prior to study entry divided by 3).
  
  

Secondary Outcome Measures:

• Number of New Or Newly Enlarging T2 Hyperintense Lesions at 1 Year [ Time Frame: 1 Year ]
  Number of new or newly enlarging T2 hyperintense lesions on brain magnetic resonance imaging (MRI) scans. Data observed after participants switched to alternative MS medications are excluded. Adjusted mean is based on negative binomial regression, adjusted for baseline number of T2 lesions.
  
  
• Proportion of Participants Relapsed at 1 Year [ Time Frame: Year 1 ]
  A relapse is defined as new or recurrent neurologic symptoms not associated with fever or infection, lasting for at least 24 hours, and accompanied by new objective neurologic findings. Only relapses confirmed by INEC were included in the analysis. Estimated proportion of participants relapsed is based on the Kaplan-Meier product limit method.
  
  
• Estimated Proportion of Participants With Sustained Disability Progression at 1 Year [ Time Frame: 1 Year ]
  Sustained disability progression is defined as: at least a 1.0 point increase on the EDSS from baseline EDSS ≥ 1.0 that is sustained for 12 weeks, or at least a 1.5 point increase on the EDSS from baseline EDSS = 0 that is sustained for 12 weeks. The EDSS measures the disability status of people with MS on a scale that ranges from 0 to 10. The range of main categories include 0 (normal neurologic examination), to 5 (ambulatory without aid or rest for 200 meters/disability severe enough to impair full daily activities), to 10 (death due to MS). Estimated proportion of participants with progression based on the Kaplan-Meier product limit method.
  
  

This is a global multicenter, randomized, double-blind, parallel-group, placebo-controlled study. The treatment period is 96 weeks (2 years) in duration. Treatment Year 1 (Week 0 to Week 48) is referred to as the placebo-controlled treatment period of the study. At the beginning of Treatment Year 1, participants were randomized to receive placebo, peginterferon beta-1a 125 μg every 2 weeks, or peginterferon beta-1a 125 μg every 4 weeks. At the end of Treatment Year 1, participants in the placebo group were re-randomized to receive peginterferon beta-1a treatment so that during treatment Year 2 (Weeks 48 to Week 96) all participants received peginterferon beta-1a 125 μg every 2 or every 4 weeks. Per protocol, all primary and secondary endpoints pertain to Year 1 data.