Celecoxib versus diclofenac for the treatment of ankylosing spondylitis: 12-week randomized study in Norwegian patients*

OBJECTIVE To compare the efficacy and safety of two different doses of celecoxib and diclofenac in the treatment of Norwegian patients with ankylosing spondylitis. METHODS In this 12-week, double-blind, non-inferiority trial patients were randomized to 200 mg once daily (qd) celecoxib, 400 mg qd celecoxib, or 50 mg three times daily (tid) diclofenac. The primary objective compared patients' assessments of Global Pain Intensity, measured on a visual analogue scale. RESULTS A total of 330 patients were randomized (200 mg celecoxib, n = 107; 400 mg celecoxib, n = 108; diclofenac, n = 115). Least squares mean changes in Global Pain Intensity at 12 weeks were -25.8 mm, -30.6 mm and -28.2 mm, respectively. Both celecoxib treatment groups were non-inferior to diclofenac. More patients in the 400 mg celecoxib group met the Assessments in Ankylosing Spondylitis 20 responder criteria at Week 12 (60.2%) than in the celecoxib 200 mg (51.4%) and the diclofenac 50 mg (57.4%) groups. Adverse events were mild-to-moderate in severity, with dyspepsia and diarrhoea the most commonly reported. CONCLUSIONS Celecoxib and diclofenac both provided pain reduction, in addition to improvements in disease activity and functional capacity, in patients with ankylosing spondylitis.