title: Basal anti-cyclic citrullinated peptide (anti-CCP) antibody levels and a decrease in anti-CCP titres are associated with clinical response to adalimumab in rheumatoid arthritis.
abstract: OBJECTIVE
  To investigate the effect of adalimumab treatment on anti-cyclic citrullinated peptide antibodies (anti-CCP) in patients with rheumatoid arthritis (RA).
  
  
  METHODS
  70 RA patients who failed treatment with disease modifying antirheumatic drugs (DMARDs) received 40 mg adalimumab subcutaneously every other week during 24 weeks. Serum samples were collected at baseline and at weeks 8, 16 and 24 before the corresponding adalimumab dose. The serum anti-CCP levels were tested by enzyme linked immunosorbent assay.
  
  
  RESULTS
  At baseline, 52 of the 70 patients (74.3%) were positive for anti-CCP antibodies. 60 % of the anti CCP positive patients and 44.4% of the anti CCP negative patients were ACR 20 responders at week 24 (p<0.049). The serum levels of anti-CCP antibodies decreased significantly after 24 weeks of adalimumab treatment only in those patients who met ACR 20 response criteria at week 24 (p<0.00044). Differences between baseline anti-CCP titers and those at 8, 16 and 24 weeks were all statistically significant (p<0.014, 0.003 and 0.019 respectively). No statistically significant changes in the anti-CCP levels were observed in patients who did not meet the ACR 20 response criteria.
  
  
  CONCLUSIONS
  Basal anti-CCP antibodies levels correlate with clinical response to adalimumab. A decrease in anti-CCP levels on time was observed in patients showing also clinical improvement, suggesting that serum anti-CCP antibodies determination may be useful in assessing treatment efficacy in RA patients.
authors.affiliation: Rheumatology Section, Department of Medicine, Clinical Hospital, University of Chile. mcuchaco@yahoo.com
authors.forename: M
authors.initials: M
authors.lastname: Cuchacovich
authors.forename: D
authors.initials: D
authors.lastname: Catalan
authors.forename: E
authors.initials: E
authors.lastname: Wainstein
authors.forename: H
authors.initials: H
authors.lastname: Gatica
authors.forename: L
authors.initials: L
authors.lastname: Soto
authors.forename: O
authors.initials: O
authors.lastname: Aravena
authors.forename: B
authors.initials: B
authors.lastname: Pesce
authors.forename: F
authors.initials: F
authors.lastname: Sabugo
authors.forename: J C
authors.initials: JC
authors.lastname: Aguillón
mesh_terms: D000068879:Adalimumab; D000328:Adult; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D061067:Antibodies, Monoclonal, Humanized; D018501:Antirheumatic Agents / Q000008:administration & dosage*; D001172:Arthritis, Rheumatoid / Q000188:drug therapy* / Q000276:immunology; D001323:Autoantibodies / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D016903:Drug Monitoring / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010456:Peptides, Cyclic / Q000276:immunology*; D011237:Predictive Value of Tests; D012217:Rheumatoid Factor / Q000097:blood; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D018501:Antirheumatic Agents; D001323:Autoantibodies; D015415:Biomarkers; D010456:Peptides, Cyclic; D014409:Tumor Necrosis Factor-alpha; C487763:cyclic citrullinated peptide; D012217:Rheumatoid Factor; D000068879:Adalimumab