Efficacy and safety of iguratimod combined with celecoxib in active axial spondyloarthritis: a randomized, double-blind, placebo-controlled study

ObjectiveTo assess the efficacy and safety of iguratimod in adult patients with active axial spondyloarthritis (axSpA).MethodThis randomized, double-blind, placebo-controlled clinical trial lasted for 28 weeks. Patients with axSpA were randomized 1:1 to receive iguratimod 25 mg twice daily or a placebo. All patients also took celecoxib 200 mg twice daily for the first 4 weeks and on demand from 4 to 28 weeks. The primary endpoints were ASAS20 at 4 weeks and the non-steroidal anti-inflammatory drug (NSAID) index at 28 weeks. Other assessment variables included ASAS40, ASAS5/6 response rates, Spondyloarthritis Research Consortium of Canada (SPARCC) scores, and adverse events.ResultsIn total, 35 patients completed the study and were included for analyses. The median (interquartile range) NSAID index was 43.8 (34.9-51.8) in the iguratimod group, which is significantly lower than 68.9 (42.5-86.4) in the placebo group (p = 0.025). ASAS response rates and changes in disease activity scores were similar between the iguratimod and placebo groups. Patients in the iguratimod group had more improvement in median (interquartile range) SPARCC scores for sacroiliac joints than did those in the placebo group [71% (54-100%) vs 40% (0-52%), p = 0.006]. Iguratimod combined with celecoxib was not associated with a greater risk of adverse effects than was monotherapy with celecoxib. No severe adverse events occurred.ConclusionsIn the treatment of active axSpA, iguratimod has a potential NSAID-sparing effect, and may also reduce magnetic resonance imaging-assessed bone marrow oedema in sacroiliac joints. Iguratimod provides an additional treatment option for patients with active axSpA.Clinical trial registration numberChiCTR2000029112, Chinese Clinical Trial Registry (http://www.chictr.org.cn)