title: Gadolinium-enhancing or active T2 magnetic resonance imaging lesions in multiple sclerosis clinical trials?
abstract: BACKGROUND
  The treatment effects in multiple sclerosis (MS) clinical trials are often estimated by monitoring disease activity by the count of "active" plaques on T2-weighted or gadolinium (Gd)-enhanced T1-weighted magnetic resonance imaging (MRI).
  
  
  OBJECTIVE
  To evaluate the relationship between the treatment effects estimated on T2-weighted or Gd-enhanced T1-weighted MRI.
  
  
  METHODS
  Data were extracted from published randomized clinical trials in relapsing-remitting MS with frequent MRI, reporting both active T2 and Gd-enhancing lesions. A regression analysis was performed between the treatment effects estimated on the two different MRI endpoints.
  
  
  RESULTS
  A strong association was found between the treatment effect on Gd-enhancing lesions and on active T2 lesions (R(2) = 0.93), and the treatment effect estimates were almost the same (slope = 0.96).
  
  
  CONCLUSIONS
  Defining either active T2 or Gd-enhancing lesions as MRI endpoint seems to be not crucial for monitoring MRI activity in MS clinical trials. The choice of the best MRI endpoint should be based on different considerations (e.g., sensitivity, reproducibility, time for assessment, safety, and patients' comfort). Further monitoring active T2 lesions could allow less expensive trials, without requiring injection of Gd-based contrast agents.
authors: Department of Neurosciences, Ophthalmology and Genetics, University of Genoa, Genoa, Italy; Magnetic Resonance Research Centre on Nervous System Diseases, University of Genoa, Genoa, Italy.
authors: L
authors: L
authors: Bonzano
authors: L
authors: L
authors: Roccatagliata
authors: G L
authors: GL
authors: Mancardi
authors: M P
authors: MP
authors: Sormani
mesh_terms: D016903:Drug Monitoring / Q000379:methods*; D005682:Gadolinium; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000188:drug therapy* / Q000473:pathology*; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data; D012044:Regression Analysis
chemical_list: D007166:Immunosuppressive Agents; D005682:Gadolinium