RESUMEN
OBJECTIVE: To compare in a 3 month, multicenter, double blind, parallel study the efficacy and safety of a nonsteroidal antiinflammatory drug, aceclofenac, 100 mg bid orally, with that of tenoxicam, 20 mg orally at bedtime, in the treatment of adult patients with active ankylosing spondylitis (AS). METHODS: A total of 273 patients (135 in the aceclofenac group and 138 in the tenoxicam group) entered the study. Eight efficacy variables were assessed: morning stiffness, visual analog pain scale, control of additional paracetamol, modified Schöber's test, C7 line-iliac crest distance, lateral flexion of the spine, thoracic expansion, and occiput-wall distance. RESULTS: Seven of the 8 variables improved significantly in both groups, with no differences between the 2 groups in any variable at the end of the study. Six percent of patients taking aceclofenac and 5% of patients taking tenoxicam withdrew because of unsatisfactory therapeutic action. Forty-two adverse events possibly or probably related to treatment were observed in the aceclofenac group and 37 in the tenoxicam group. However, only 2.2% of patients in the aceclofenac group and 1.4% in the tenoxicam group withdrew for this reason. CONCLUSION: Aceclofenac and tenoxicam are similar in terms of safety and effectiveness; and aceclofenac, 100 mg orally twice daily, is a safe, effective, and convenient treatment for active AS.