title: Safety and efficacy of readministration of infliximab after longterm continuous therapy and withdrawal in patients with ankylosing spondylitis.
abstract: OBJECTIVE
  To analyze the safety and efficacy of the anti-tumor necrosis factor agent infliximab in patients with ankylosing spondylitis (AS) after discontinuation of longterm therapy over 1 year and readministration, using clinical and laboratory assessments including serum levels of antibodies to infliximab (ATI).
  
  
  METHODS
  Altogether 42/43 patients with AS in a 3-year multicenter trial discontinued therapy after continuous treatment with infliximab (5 mg/kg/6 wks). Infliximab was only readministered in case of a clinical relapse [judged by Bath AS Disease Activity Index (BASDAI) and physician global assessment > 4]. ATI were measured at different timepoints. The primary outcome was safety, and efficacy outcomes were secondary.
  
  
  RESULTS
  One patient dropped out after the eighth infusion after retreatment due to repeated local infections. ATI were detected in this patient only. No other relevant adverse events were observed. One patient remained in clinical remission without therapy for more than 1 year. The other 40 patients (97.6%) were reinfused because of clinical relapse. There was no correlation between ATI and clinical measures. BASDAI 50% responses were seen in 25 (63%) and partial remission in 12 (30%) patients. The mean (+/- SD) BASDAI score dropped from 6.0 +/- 1.4 at the time of relapse to 2.6 +/- 2.0, and the median C-reactive protein from 11.2 to 1.8 mg/l after 1 year (all p < 0.05).
  
  
  CONCLUSIONS
  Readministration of infliximab after discontinuation of longterm treatment was generally safe and efficacious. Ongoing remission after discontinuation was rare. There was only one patient with relevant adverse events. ATI were detected only in this patient, but there was no correlation to clinical data. Formation of ATI seems to be rare after longterm infliximab therapy in AS.
authors.affiliation: Rheumazentrum Ruhrgebiet, Herne; Ruhr University, Bochum, Germany.
authors.forename: Xenofon
authors.initials: X
authors.lastname: Baraliakos
authors.forename: Joachim
authors.initials: J
authors.lastname: Listing
authors.forename: Martin
authors.initials: M
authors.lastname: Rudwaleit
authors.forename: Jan
authors.initials: J
authors.lastname: Brandt
authors.forename: Rieke
authors.initials: R
authors.lastname: Alten
authors.forename: Gerd
authors.initials: G
authors.lastname: Burmester
authors.forename: Erika
authors.initials: E
authors.lastname: Gromnica-Ihle
authors.forename: Hildrun
authors.initials: H
authors.lastname: Haibel
authors.forename: Stephan
authors.initials: S
authors.lastname: Schewe
authors.forename: Matthias
authors.initials: M
authors.lastname: Schneider
authors.forename: Helmut
authors.initials: H
authors.lastname: Sörensen
authors.forename: Henning
authors.initials: H
authors.lastname: Zeidler
authors.forename: Sudha
authors.initials: S
authors.lastname: Visvanathan
authors.forename: Joachim
authors.initials: J
authors.lastname: Sieper
authors.forename: Juergen
authors.initials: J
authors.lastname: Braun
mesh_terms: D000911:Antibodies, Monoclonal / Q000008:administration & dosage* / Q000009:adverse effects / Q000276:immunology; D018501:Antirheumatic Agents / Q000008:administration & dosage* / Q000009:adverse effects / Q000276:immunology; D004334:Drug Administration Schedule; D006801:Humans; D000069285:Infliximab; D012008:Recurrence; D012720:Severity of Illness Index; D013167:Spondylitis, Ankylosing / Q000188:drug therapy*; D016896:Treatment Outcome
chemical_list: D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents; D000069285:Infliximab