Aim of the study: This study aims to explore the efficacy and safety of Feng Shi Gu Tong Wan in the treatment of ankylosing spondylitis.
Materials and methods: This randomized, controlled, double-blinded, double-dummy trial enrolled patients with active ankylosing spondylitis defined as Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) ≥ 4 or Ankylosing Spondylitis Disease Activity Score with C-reactive protein (ASDAS-CRP) ≥ 2.1.
Eligible patients were randomized (1:1:1) into combination group (Feng Shi Gu Tong Wan plus imrecoxib), Feng Shi Gu Tong Wan group (Feng Shi Gu Tong Wan plus imrecoxib placebo) or imrecoxib group (imrecoxib plus Feng Shi Gu Tong Wan placebo) over a 4-week treatment. The primary endpoint was the composite outcome measure of the Assessment in Ankylosing Spondylitis 20% (ASAS20) response at week 4.
The secondary endpoints included ASDAS-CRP, BASDAI, Bath Ankylosing Spondylitis Functional Index (BASFI), Bath Ankylosing Spondylitis Metrology Index (BASMI), patient’s global assessment of disease activity (PGTA) and safety.
Results: Of the 180 randomized patients, 159 patients (88.3%) completed the 4-week treatment. ASAS20 response rate at week 4 was achieved by 27.5% in imrecoxib group, compared with 37.0% in combination group (P > 0.05) and 37.0% in Feng Shi Gu Tong Wan group (P > 0.05).
In comparison to imrecoxib group, there were significantly greater improvements of ASDAS-CRP and PTGA in combination group and greater improvement of ASDAS-CRP in FSGTC group while the rest of the secondary endpoints shown similar improvement.
The incidence of gastrointestinal adverse events in imrecoxib group (15.7%) was significantly higher than that of Feng Shi Gu Tong Wan group (1.9%) and without a significant difference to combination group (7.4%).
Conclusion: Feng Shi Gu Tong Wan alone or combined with NSAIDs has therapeutic efficacy in decreasing disease activity of active ankylosing spondylitis patients and with good gastrointestinal tolerability after 4-week of treatment.