Baricitinib for Takayasu arteritis refractory to TNF-α inhibitors: a multi-centre, single-arm trial

Abstract Objective This study aimed to assess the efficacy and safety of baricitinib in Takayasu arteritis (TAK) refractory to TNF-α inhibitors. Methods We conducted a multicentre, single-arm trial between February 2021 and August 2023. Patients with TAK unresponsive to at least 6 months of TNF-α inhibitors were treated with baricitinib 4 mg daily for up to 48 weeks, while continuing of immunosuppressants and glucocorticoids. Clinical features, inflammatory parameters, imaging changes, and treatment data were collected during follow-up. The primary end point was the overall response (ORR) (complete response [CR] plus partial response [PR]) at 24 weeks. Results A total of ten patients (9 female and 1 male) patients were enrolled, with median age of 29 years (26.0, 35.3) and a median disease duration of 56.5 months (31.8, 88.5). The ORR at 24 weeks was 80%, with six patients achieving CR and two achieving PR. Disease progression was noted in the remaining two patients. Disease activity, erythrocyte sedimentation rate, and C-reactive protein at 24 weeks were significantly decreased compared with those at baseline. The median glucocorticoid dosage decreased from 20.0 mg/day (15.0, 26.3) at baseline (p< 0.001)–6.3 mg/day (4.4, 10.6) at 24 weeks. No relapse was observed in the eight patients who achieved a response. The adverse effects (AEs) included upper respiratory tract infection (n = 2) and diarrhoea (n = 1), with no serious AEs reported. Conclusion Baricitinib is effective in patients with TAK resistant to conventional treatments and anti-TNF-α therapy and demonstrates a notable steroid-sparing effect. Trial registration ClinicalTrials.gov; NCT06662721