Outcome of patients with active ankylosing spondylitis after two years of therapy with etanercept: clinical and magnetic resonance imaging data

Arthritis Rheum. 2005 Dec 15;53(6):856-63. doi: 10.1002/art.21588.


Objective: To examine the long-term outcome of patients with active ankylosing spondylitis (AS) clinically and by magnetic resonance imaging (MRI) after continuous treatment with the tumor necrosis factor (TNF) receptor fusion protein etanercept over 2 years.

Methods: Overall, 26 patients with active AS were treated with etanercept 25 mg twice daily subcutaneously, twice weekly with no concomitant disease-modifying antirheumatic drugs (DMARDs) or steroids. The clinical response was assessed by standardized parameters. Inflammatory spinal lesions were quantified by the ASspiMRI-a rating gadolinium-enhanced (T1-weighted gadolinium diethylenetriaminepentaacetic acid) and STIR MRI sequences. The primary outcome was a Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) improvement > or =50% after 2 years of etanercept therapy compared with the baseline value of the study.

Results: Overall, 21 (70%) of 30 patients completed year 2. In the intent-to-treat analysis, 54% of the patients showed a 50% improvement according to the BASDAI and a 40% improvement according to the Assessment in Ankylosing Spondylitis (ASAS) criteria. In the completer analysis, 9 (43%) of 21 patients were in partial remission according to ASAS criteria. Mean +/- SD BASDAI scores, which were elevated at baseline (6.3 +/- 1.6), remained low: 2.7 +/- 2.4 after 2 years compared with 2.6 +/- 2.2 at week 54. In accordance, all other clinical parameters showed sustained improvement during year 2. The majority of patients had no disease activity flares. MRI evaluation showed a 75% improvement of active spinal lesions, but minor spinal inflammation was still present in 64% of the patients after 2 years. There were 2 serious adverse events leading to discontinuation of etanercept.

Conclusion: The clinical efficacy and safety of etanercept in patients with active AS without simultaneous administration of DMARDs or steroids over 2 years of continuous treatment is confirmed. Spinal inflammation as depicted by MRI decreased significantly, but a few patients still had some spinal inflammation even after long-term anti-TNF therapy.

Publication types

  • Controlled Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Antirheumatic Agents / therapeutic use*
  • Etanercept
  • Female
  • Health Status
  • Humans
  • Immunoglobulin G / therapeutic use*
  • Magnetic Resonance Imaging*
  • Male
  • Receptors, Tumor Necrosis Factor / therapeutic use*
  • Recombinant Fusion Proteins*
  • Severity of Illness Index
  • Spondylitis, Ankylosing / diagnosis
  • Spondylitis, Ankylosing / drug therapy*
  • Spondylitis, Ankylosing / physiopathology
  • Time Factors
  • Treatment Outcome


  • Antirheumatic Agents
  • Immunoglobulin G
  • Receptors, Tumor Necrosis Factor
  • Recombinant Fusion Proteins
  • Etanercept