Baricitinib in Combination with High-Dose Dexamethasone As First-Line Treatment for Newly Diagnosed Immune Thrombocytopenia: A Prospective, Multicenter, Randomized Trial

Introduction: High-dose dexamethasone is among the standard initial therapeutic options for patients with newly diagnosed immune thrombocytopenia (ITP). Although most patients achieve initial remission, optimal first-line therapy remains a challenge due to the low rates of sustained response and the high incidence of corticosteroid-dependency. Antiplatelet autoantibodies and splenic macrophages play central roles in the pathogenesis of ITP. Baricitinib, a Janus-associated kinase 1/2 (JAK1/2) inhibitor, can inhibit antigen presentation by innate immune cells and subsequent T-cell activation while also alleviating B-cell abnormalities and antibody production. The results of our single-arm pilot study suggested that baricitinib might increase the rate of durable response in patients with steroid-resistant or relapsed ITP (NCT05446831, presented at EHA2023, P1594). Accordingly, we further conducted a randomized, controlled trial to evaluate the efficacy and safety of baricitinib plus high-dose dexamethasone as first-line therapy for adulthood ITP. Methods: This multicenter, open-label, randomized, controlled, phase 2 trial was conducted in 10 different tertiary medical centers in China. Adult patients with newly diagnosed, treatment-naïve, confirmed primary ITP who had a platelet count