The aim of the present study was to assess the efficacy and safety of loxoprofen sodium hydrogel patch (LX-P) vs. loxoprofen sodium tablet (LX-T) in patients with active ankylosing spondylitis (AS). The study population consisted of patients who met the modified New York radiographic criteria for AS and had active disease. Patients were randomly assigned to either the LX-P group (LX-P 100 mg per day) or LX-T group (LX-T 60 mg 3 times daily) for 4 weeks. The primary efficacy endpoint was the percentage of patients reaching Assessment in Ankylosing Spondylitis 20% (ASAS20) response at week 4. Secondary efficacy outcomes included ASAS5/6 response rate and changes from baseline to week 4 for Ankylosing Spondylitis Disease Activity Score, patient's global assessment of disease activity, and pain score. Of the 70 randomized patients included, 35 patients were allocated to the LX-P group and 35 to the LX-T group. No significant differences were observed between the LX-P and LX-T groups in the proportion of patients achieving ASAS20 response at week 4 (54.3 vs. 74.3%; P=0.081), nor in the ASAS5/6 response and changes of efficacy outcomes between the two groups. Furthermore, patients without peripheral arthritis in the LX-P group were more likely to achieve ASAS20 response. There was a decreased incidence of gastrointestinal adverse events in the LX-P group, but this was not significant. There was no significant differences in efficacy and safety between topical LX-P and oral LX-T administration for patients with active AS.
Keywords: ankylosing spondylitis; hydrogel patch; loxoprofen; topical application.