BETAFERON in clinically isolated syndrome (CIS): The BENEFIT study
The BENEFIT study evaluated the efficacy and safety of BETAFERON in early MS and led to the approval of BETAFERON in CIS. In the study, 468 patients with a first clinical event suggestive of MS were randomly allocated to receive either BETAFERON (n=292) or placebo (n=176) every other day until clinically definite MS (CDMS) or for 2 years. Primary endpoints were time to CDMS and time to McDonald MS (MS defined according to the 2001 McDonald criteria) .
In the 2-year core study of the BENEFIT trial, treatment with BETAFERON:
- reduced the risk of conversion to CDMS by 50% compared with the placebo group (hazard ratio: 0.50; 95% CI: 0.36-0.70, P<0.0001) 
- reduced the risk of conversion to McDonald MS by 46% compared with the placebo group (hazard ratio: 0.54; 95% CI: 0.43-0.67, P<0.00001) 
- delayed conversion to CDMS by almost a full year at the 25th percentile  (see figure)
Time (days) to clinically definite MS in the BENEFIT study 
The patients included in the BENEFIT study were prospectively followed up for up to 5 years and in due course in different follow-up studies up to year 15 [2-6].
CI: confidence interval
- Kappos L et al. Neurology 2006; 67(7): 1242-9. Return to content
- Kappos L et al. Lancet 2007; 370: 389-97. Return to content
- Kappos L et al. Lancet Neurology 2009; 8(11): 987-97. Return to content
- Edan G et al. J Neurol Neurosurg Psychiatry 2014; 85(11): 1183-9. Return to content
- Kappos L et al. Neurology 2016; 87(10): 978-87. Return to content
- Kappos L et al. American Academy of Neurology, Annual Meeting 2019, P3.2-080. Return to content