Efficacy and Safety of Celecoxib in Chinese Patients with Ankylosing Spondylitis: A 6-Week Randomized, Double-Blinded Study with 6-Week Open-Label Extension Treatment

BACKGROUND: Nonsteroidal anti-inflammatory drugs are the first-line option for treating ankylosing spondylitis (AS) in China. However, no large-scale controlled trials have been conducted in this ethnic population. OBJECTIVE: To evaluate the efficacy and safety of 6 weeks’ treatment with celecoxib in patients with AS in China. METHODS: This Phase 3, double-blind, parallel-group study randomized patients with AS aged ≥18 to 65 years 1:1 to receive celecoxib 200 mg once daily or diclofenac sustained release 75 mg once daily. After 6 weeks, patients could use celecoxib 400 mg once daily or maintain blinded therapy. The primary efficacy end point was mean change from baseline at Week 6 for Patient’s Global Assessment of Pain Intensity score (100-mm visual analog scale). Noninferiority was established if the upper bound of the CI was <10 mm. Secondary objectives included patients’ and physicians’ assessments of disease activity, change from baseline in C-reactive protein level, and safety. RESULTS: In the per-protocol analysis set the least squares mean change from baseline in the Patient’s Global Assessment of Pain Intensity score at Week 6 was –23.8 mm and –27.1 mm in patients receiving celecoxib (n = 111) and diclofenac (n = 108), respectively. The 2-sided 95% CI for the treatment difference (celecoxib – diclofenac) was –2.2 to 8.8. Overall, 4.2% and 6.7% of patients in the celecoxib and diclofenac groups, respectively, reported treatment-related adverse events. All were mild to moderate in severity. CONCLUSIONS: Celecoxib 200 mg once daily is noninferior to diclofenac sustained release 75 mg once daily for pain treatment in Chinese patients with AS. ClinicalTrials.gov identifier: NCT00762463.