title: ACCLAIM: A randomized trial of abatacept (CTLA4-Ig) for relapsing-remitting multiple sclerosis.
abstract: BACKGROUND
  Costimulatory blockade of T lymphocytes with the CTLA4-Ig fusion protein abatacept could be an effective treatment for the immune-mediated neuroinflammatory disease relapsing-remitting multiple sclerosis (RRMS).
  
  
  OBJECTIVE
  To evaluate efficacy and safety of abatacept in RRMS.
  
  
  METHODS
  ACCLAIM (A Cooperative Clinical Study of Abatacept in Multiple Sclerosis) was a Phase II, randomized, double-blind, placebo-controlled, multi-center trial. In all, 65 of 123 planned participants with RRMS were randomized to monthly intravenous infusions of abatacept or placebo for 24 weeks in a 2:1 ratio, switched to the opposite treatment at 28 weeks, and received their final dose of study medication at 52 weeks. Enrollment was closed early due to slow accrual. The primary endpoint was the mean number of new gadolinium-enhancing (Gd+) lesions obtained on magnetic resonance imaging (MRI) scans performed every 4 weeks.
  
  
  RESULTS
  No statistically significant differences were observed in mean number of new Gd+ MRI lesions between the abatacept and placebo groups. No statistically significant differences were observed in other MRI and clinical parameters of RRMS disease activity. Abatacept was well tolerated.
  
  
  CONCLUSIONS
  The ACCLAIM study did not demonstrate efficacy of abatacept in reducing the number of new Gd+ MRI lesions, or clinical measures of disease activity in RRMS.
authors.affiliation: Partners Multiple Sclerosis Center, Brigham and Women's Hospital, Boston, MA, USA/Abu Haidar Neuroscience Institute, American University of Beirut, Beirut, Lebanon.
authors.forename: Samia J
authors.initials: SJ
authors.lastname: Khoury
authors.affiliation: Rho, Inc., Chapel Hill, NC, USA.
authors.forename: James
authors.initials: J
authors.lastname: Rochon
authors.affiliation: Division of Allergy, Immunology, and Transplantation, National Institute of Allergy and Infectious Diseases, Rockville, MD, USA.
authors.forename: Linna
authors.initials: L
authors.lastname: Ding
authors.affiliation: Rho, Inc., Chapel Hill, NC, USA.
authors.forename: Margie
authors.initials: M
authors.lastname: Byron
authors.affiliation: Immune Tolerance Network, San Francisco, CA, USA.
authors.forename: Kristin
authors.initials: K
authors.lastname: Ryker
authors.affiliation: Immune Tolerance Network, San Francisco, CA, USA.
authors.forename: Patti
authors.initials: P
authors.lastname: Tosta
authors.affiliation: Division of Allergy, Immunology, and Transplantation, National Institute of Allergy and Infectious Diseases, Rockville, MD, USA.
authors.forename: Wendy
authors.initials: W
authors.lastname: Gao
authors.affiliation: University of Ottawa, Ottawa, ON, Canada.
authors.forename: Mark S
authors.initials: MS
authors.lastname: Freedman
authors.affiliation: NeuroRx Research and McGill University, Montreal, QC, Canada.
authors.forename: Douglas L
authors.initials: DL
authors.lastname: Arnold
authors.affiliation: Immune Tolerance Network, San Francisco, CA, USA.
authors.forename: Peter H
authors.initials: PH
authors.lastname: Sayre
authors.affiliation: Immune Tolerance Network, San Francisco, CA, USA.
authors.forename: Dawn E
authors.initials: DE
authors.lastname: Smilek
mesh_terms: D000069594:Abatacept / Q000627:therapeutic use*; D000328:Adult; D004311:Double-Blind Method; D005260:Female; D005682:Gadolinium / Q000494:pharmacology; D006801:Humans; D016899:Interferon-beta / Q000627:therapeutic use; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000188:drug therapy*; D016896:Treatment Outcome
chemical_list: D016899:Interferon-beta; D000069594:Abatacept; D005682:Gadolinium
keywords: Abatacept; autoimmune diseases; clinical trial; costimulatory and inhibitory T-cell receptors; gadolinium; intervention study; magnetic resonance imaging; multiple sclerosis; relapsing-remitting