The feasible maintenance dose of corticosteroid in Takayasu arteritis in the era of biologic therapy.

Objective: Although biologic agents are used in Takayasu arteritis (TAK), corticosteroids are still the mainstay of treatment. This study aimed to investigate the feasible maintenance dose of prednisolone (PSL) in the biologic therapy era.Method: We enrolled 93 patients with TAK who satisfied the criteria of the American College of Rheumatology and visited our department from 2008 to 2018. The clinical characteristics and PSL dose of the patients were retrospectively evaluated.Results: The mean ± sd maintenance dose of PSL was 5.0 ± 3.0 mg/day. In patients having TAK for > 20 years, PSL discontinuation and drug-free status were achieved in 27.2% and 18%, respectively. Although tapering the PSL dose to 10 mg/day was achieved within 12 months, tapering to 5 mg/day required 10 years. Relapse significantly interfered with the PSL dose reduction. The clinical characteristics of patients with relapse included a lower rate of combination therapy using immunosuppressants. Moreover, biologics were used in > 60% of patients with relapse. Tapering of PSL was significantly possible in patients receiving biologics and additional relapse was observed in 6.3% and 50% of patients with and without biologics, respectively. Such PSL-sparing effect enabled the reduction of the median PSL dose from 10 to 5 mg/day. Steroid discontinuation was achieved in some patients.Conclusions: The use of biologics significantly reduced the PSL dose in relapsed patients. A PSL dose of ≤ 5 mg/day is a feasible target for TAK, especially when biologic agents are used. Nevertheless, corticosteroid discontinuation may also be the target in some patients.