A Multicenter，Double-Blind and Randomized Controlled Trial of Fengshigutong Capsule in the Treatment of Ankylosing Spondylitis

Inclusion Criteria: * 18 to 65 years * Meet 1984 modified New York criteria for AS * The Bath AS Disease Activity Index (BASDAI) ≥4 on a 0-10-cm visual analog scale or the Ankylosing Spondylitis Disease Activity Score using the C-reactive protein level (ASDAS-CRP) ≥1.3 * NSAIDs washout period of at least 7 days prior to randomization * DMARDs washout period of at least 4 weeks prior to randomization * Corticosteroids washout period of at least 2 weeks prior to randomization * Biological agents washout period of at least 3 months prior to randomization. Exclusion Criteria: * Peptic ulcer * Unstable cardiac diseases * Hematologic disorders * Psychosis * Malignancy * Multiple sclerosis * severe COPD * fibromyalgia and other rheumatic disease * Corticosteroids were injected into the articular cavity within 3 months * Chinese medicine was taken within 28 days * Pregnant and lactating women * Alcohol and drug abuse * Spinal cord compression