title: Treatment of active ankylosing spondylitis with abatacept: an open-label, 24-week pilot study.
abstract: OBJECTIVE
  To prospectively explore the short-term efficacy and safety of abatacept in patients with ankylosing spondylitis (AS).
  
  
  METHODS
  In this prospective open-label pilot study, abatacept (10 mg/kg) was administered intravenously on days 1, 15, 29 and every 28 days thereafter up to week 24 in 15 tumour necrosis factor α (TNFα)-inhibitor naive patients (group 1) and 15 patients with inadequate response to TNFα inhibitors (group 2) with active AS. The primary end point was the proportion of patients with 40% improvement according to the Assessment of SpondyloArthritis international Society criteria (ASAS40) in both groups at week 24.
  
  
  RESULTS
  At week 24, ASAS40 was reached by 13% of group 1 and 0% of group 2; 20% improvement (ASAS20) was reached by 27% and 20%, respectively. There was no significant change of Bath Ankylosing Spondylitis Disease Activity Index score, patient global assessment or C reactive protein. Overall, abatacept was well tolerated.
  
  
  CONCLUSIONS
  In this pilot open-label AS study a major response was not observed.
authors.affiliation: Department of Rheumatology, Charité Medical University, Campus Benjamin Franklin, Berlin, Germany.
authors.forename: I-H
authors.initials: IH
authors.lastname: Song
authors.forename: F
authors.initials: F
authors.lastname: Heldmann
authors.forename: M
authors.initials: M
authors.lastname: Rudwaleit
authors.forename: H
authors.initials: H
authors.lastname: Haibel
authors.forename: A
authors.initials: A
authors.lastname: Weiss
authors.forename: J
authors.initials: J
authors.lastname: Braun
authors.forename: J
authors.initials: J
authors.lastname: Sieper
mesh_terms: D000069594:Abatacept; D000328:Adult; D018501:Antirheumatic Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D004334:Drug Administration Schedule; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D018796:Immunoconjugates / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D007166:Immunosuppressive Agents / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D013167:Spondylitis, Ankylosing / Q000188:drug therapy*; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors
chemical_list: D018501:Antirheumatic Agents; D018796:Immunoconjugates; D007166:Immunosuppressive Agents; D014409:Tumor Necrosis Factor-alpha; D000069594:Abatacept