Clinical trial of Leflunomide in active ankylosing spondylitis

[Objective] To assess the efficacy and safety of Leflunomide in active ankylosing spondylitis. [Methods] 40 cases of active ankylosing spondylitis (6~50 years old, disease duration 0.5~8.0 years) meeting the 1984 modified New York criteria were included. The patients received a Leflunomide loading dose of 50 mg or 40 mg once daily for the first 3 days followed by a maintenance dose of 50 mg or 40 mg once weekly, according to whether the bodyweight is more than 50 kg or less than 50 kg, respectively. Sulfasalazine was prescribed 0.75 three times daily. The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and The Bath Ankylosing Spondylitis Metrology Index (BASIM) scoring instruments have been used to assess the responsiveness of Leflunomide therapy at study entry, three months, six months, twelve months and eighteen months after treatment, respectively. Laboratory data including peripheral blood counts (WBC, HGB, RBC), erythrocyte sedimentation rates (ESR), liver enzymes, serum creatinine, urinary sediments were detected at the same time. Sacroiliac joints CT scan and other involved joints x-ray radiograph examinations were taken at study entry, six months, twelve months, eighteen months after treatment, respectively. [Results] 36 cases were followed up to eighteen months. At three months, six months, twelve months and eighteen months, BASDAI, BASMI and ESR were all lower significantly (P 0.01) compared with study entry, three months, six months, twelve months, respectively. No deterioration with sacroiliac joints on CT scan and the involved joints on x-ray raidographs was found. Adverse events were monitered as transient and mild oral ulcer, leukocytopenia, hypentension, elevated transaminase (ALT, GGT), and a case of severe malaise. [Conclusion] Leflunomide shows good efficacy and safety in active ankylosing spondylitis.