title: Comparative Effectiveness of Infliximab and Adalimumab in Crohn's Disease and Ulcerative Colitis.
abstract: BACKGROUND
  The availability of monoclonal antibodies to tumor necrosis factor α has revolutionized management of Crohn's disease (CD) and ulcerative colitis. However, limited data exist regarding comparative effectiveness of these agents to inform clinical practice.
  
  
  METHODS
  This study consisted of patients with CD or ulcerative colitis initiation either infliximab (IFX) or adalimumab (ADA) between 1998 and 2010. A validated likelihood of nonresponse classification score using frequency of narrative mentions of relevant symptoms in the electronic health record was applied to assess comparative effectiveness at 1 year. Inflammatory bowel disease-related surgery, hospitalization, and use of steroids were determined during this period.
  
  
  RESULTS
  Our final cohort included 1060 new initiations of IFX (68% for CD) and 391 of ADA (79% for CD). In CD, the likelihood of nonresponse was higher in ADA than IFX (odds ratio, 1.62 and 95% CI, 1.21-2.17). Similar differences favoring efficacy of IFX were observed for the individual symptoms of diarrhea, pain, bleeding, and fatigue. However, there was no difference in inflammatory bowel disease-related surgery, hospitalizations, or prednisone use within 1 year after initiation of IFX or ADA in CD. There was no difference in narrative or codified outcomes between the 2 agents in ulcerative colitis.
  
  
  CONCLUSIONS
  We identified a modestly higher likelihood of symptomatic nonresponse at 1 year for ADA compared with IFX in patients with CD. However, there were no differences in inflammatory bowel disease-related surgery or hospitalizations, suggesting these treatments are broadly comparable in effectiveness in routine clinical practice.
authors.affiliation: *Division of Gastroenterology, Massachusetts General Hospital, Boston, Massachusetts; †Harvard Medical School, Boston, Massachusetts; ‡Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts; §Research IS and Computing, Partners HealthCare, Charlestown, Massachusetts; ‖Department of Biostatistics, Harvard School of Public Health, Boston, Massachusetts; ¶Center for Systems Biology, Massachusetts General Hospital, Boston, Massachusetts; **Children's Hospital Informatics Program, Boston Children's Hospital, Boston, Massachusetts; ††Center for Biomedical Informatics, Harvard Medical School, Boston, Massachusetts; ‡‡Division of Rheumatology, Allergy and Immunology, Brigham and Women's Hospital, Boston, Massachusetts; §§Children's Hospital Boston, Boston, Massachusetts; and ‖‖Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Ashwin N
authors.initials: AN
authors.lastname: Ananthakrishnan
authors.forename: Andrew
authors.initials: A
authors.lastname: Cagan
authors.forename: Tianxi
authors.initials: T
authors.lastname: Cai
authors.forename: Vivian S
authors.initials: VS
authors.lastname: Gainer
authors.forename: Stanley Y
authors.initials: SY
authors.lastname: Shaw
authors.forename: Guergana
authors.initials: G
authors.lastname: Savova
authors.forename: Susanne
authors.initials: S
authors.lastname: Churchill
authors.forename: Elizabeth W
authors.initials: EW
authors.lastname: Karlson
authors.forename: Isaac
authors.initials: I
authors.lastname: Kohane
authors.forename: Katherine P
authors.initials: KP
authors.lastname: Liao
authors.forename: Shawn N
authors.initials: SN
authors.lastname: Murphy
mesh_terms: D000068879:Adalimumab / Q000627:therapeutic use*; D000328:Adult; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D003093:Colitis, Ulcerative / Q000188:drug therapy*; D003424:Crohn Disease / Q000188:drug therapy*; D004359:Drug Therapy, Combination; D005260:Female; D005500:Follow-Up Studies; D005765:Gastrointestinal Agents / Q000627:therapeutic use; D006801:Humans; D000069285:Infliximab / Q000627:therapeutic use*; D008297:Male; D011379:Prognosis; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors*
chemical_list: D000893:Anti-Inflammatory Agents; D005765:Gastrointestinal Agents; D014409:Tumor Necrosis Factor-alpha; D000069285:Infliximab; D000068879:Adalimumab