title: The clinical relevance of early anti-adalimumab antibodies detection in rheumatoid arthritis, ankylosing spondylitis and psoriatic arthritis: A prospective multicentre study.
abstract: OBJECTIVE
  To evaluate the relevance of anti-adalimumab (anti-ADA) antibodies (Abs) and their relationship with clinical/laboratory features in rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA).
  
  
  METHODS
  Fifty-eight patients affected with RA, AS and PsA were prospectively enrolled. Clinical/laboratory characteristics, disease activity, anti-ADA, anti-nuclear (ANA), anti-double strand (ds)DNA, anti-extractable nuclear antigens (anti-ENA) and anti-phospholipid Abs (aPL) were evaluated at baseline, 4, 12 and 24 weeks of adalimumab treatment.
  
  
  RESULTS
  Anti-ADA Abs were observed in 11/58 (19%) patients; they were detected within the 4th week of therapy in 90.9% of the positive subjects. Anti-ADA positivity was associated with significantly lower mean adalimumab serum levels (P<0.05). Treatment failure was observed in 20/58 (34.5%) patients and was significantly associated with anti-ADA Abs (P<0.05). Mean adalimumab serum levels were significantly lower in patients with treatment failure than in the responders one, both in the whole cohort (P<0.01) and in the group of anti-ADA positive patients (P<0.01). Adverse events happened more often in anti-ADA positive then in anti-ADA negative patients (27.3% vs 14.9%).
  
  
  CONCLUSIONS
  Anti-ADA abs could be considered an early marker associated to a poor clinical response to adalimumab treatment. Routine ANA/anti-ENA/aPL monitoring did not reveal as useful tools to predict the development of anti-ADA abs.
authors.affiliation: Rheumatology Unit, Department of Medicine, University of Padua, Via Giustiniani, 2-35128 Padova, Italy. Electronic address: arielahoxha@hotmail.com.
authors.forename: Ariela
authors.initials: A
authors.lastname: Hoxha
authors.affiliation: Rheumatology Unit, Department of Medicine, University of Padua, Via Giustiniani, 2-35128 Padova, Italy.
authors.forename: Antonia
authors.initials: A
authors.lastname: Calligaro
authors.affiliation: Rheumatology Unit, Department of Medicine, University of Padua, Via Giustiniani, 2-35128 Padova, Italy.
authors.forename: Marta
authors.initials: M
authors.lastname: Tonello
authors.affiliation: Rheumatology Unit, Department of Medicine, University of Padua, Via Giustiniani, 2-35128 Padova, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Ramonda
authors.affiliation: Rheumatology Unit, Department of Medicine, University of Verona, Piazzale L.A. Scuro 10, 37134 Verona, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Carletto
authors.affiliation: Rheumatology Unit, S. Chiara Hospital, Largo Medaglie D'oro, 9, 38122 Trento, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Paolazzi
authors.affiliation: Rheumatology Unit, S. Chiara Hospital, Largo Medaglie D'oro, 9, 38122 Trento, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Bortolotti
authors.affiliation: Rheumatology Unit, Department of Medicine, University of Padua, Via Giustiniani, 2-35128 Padova, Italy.
authors.forename: Teresa
authors.initials: T
authors.lastname: Del Ross
authors.affiliation: Department of Medicine, S. Martino Hospital, Viale Europa, 22, 32100 Belluno, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Grava
authors.affiliation: Department of Medicine, S. Martino Hospital, Viale Europa, 22, 32100 Belluno, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Boaretto
authors.affiliation: Rheumatology Unit, Department of Medicine, University of Padua, Via Giustiniani, 2-35128 Padova, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Favaro
authors.affiliation: Rheumatology Unit, Department of Medicine, University of Padua, Via Giustiniani, 2-35128 Padova, Italy.
authors.forename: Vera
authors.initials: V
authors.lastname: Teghil
authors.affiliation: Rheumatology Unit, Department of Medicine, University of Padua, Via Giustiniani, 2-35128 Padova, Italy.
authors.forename: Amelia
authors.initials: A
authors.lastname: Ruffatti
authors.affiliation: Rheumatology Unit, Department of Medicine, University of Padua, Via Giustiniani, 2-35128 Padova, Italy.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Punzi
mesh_terms: D000068879:Adalimumab / Q000032:analysis / Q000276:immunology*; D000328:Adult; D061067:Antibodies, Monoclonal, Humanized / Q000032:analysis / Q000276:immunology*; D018501:Antirheumatic Agents / Q000032:analysis / Q000276:immunology*; D015535:Arthritis, Psoriatic / Q000188:drug therapy / Q000276:immunology*; D001172:Arthritis, Rheumatoid / Q000188:drug therapy / Q000276:immunology*; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013167:Spondylitis, Ankylosing / Q000188:drug therapy / Q000276:immunology*
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D018501:Antirheumatic Agents; D000068879:Adalimumab
keywords: Ankylosing spondylitis; Anti-adalimumab antibodies; Psoriatic arthritis; Rheumatoid arthritis