原发性免疫性血小板减少症（primary immune thrombocytopenia，ITP）是一种获得性自身免疫性疾病，以血小板破坏增加和血小板生成受损引起的孤立性血小板减少为特征。虽然多数患者预后相对良好，然而仍有10%~20%的儿童患者，以及高达75%的成人患者可能发展为慢性原发性免疫性血小板减少症（chronic primary immune thrombocytopenia，CITP）。该类患者对多种治疗手段的效果均不明显，生活质量受到严重影响。当前，CITP的治疗策略主要包括糖皮质激素及丙种球蛋白在内的一线疗法，以及血小板生成素受体激动剂（thrombopoietin receptor agonist，TPO-RA）、利妥昔单克隆抗体、免疫抑制剂和脾切除等二线疗法。近年来，随着对CITP研究的深入，一些新型生物药物和免疫疗法，例如Fcγ受体（Fcγ receptor，FcγR）信号转导抑制剂、新生儿Fc受体抑制剂、补体抑制剂、免疫细胞靶向治疗、血小板去唾液酸化、脐带间充质干细胞治疗以及嵌合抗原受体T细胞免疫疗法等，显示出良好的治疗潜力。新型疗法通过针对CITP发病机制的不同环节进行干预，旨在实现个体化精准治疗，从而为患者提供更为有效的治疗选择。该文就CITP的发病机制、二线治疗方法以及治疗研究进展进行综述。

Primary immune thrombocytopenia (ITP) is an acquired autoimmune disease characterized by isolated thrombocytopenia resulting from increased platelet destruction and impaired platelet production. Although the majority of patients have a relatively good prognosis, 10%‒20% of children and up to 75% of adults may progress to chronic primary immune thrombocytopenia (CITP). These patients exhibit poor response to multiple therapies, leading to a significant decline in quality of life. At present, the treatment strategies for CITP mainly include first-line therapies such as glucocorticoids and gamma globulin, and second-line therapies such as thrombopoietin receptor agonists (TPO-RAs), rituximab, immunosuppressants, and splenectomy. In recent years, with the in-depth research on CITP, some new biological drugs and immunotherapies, such as Fcγ receptor (FcγR) signal transduction inhibitors, neonatal Fc receptor inhibitors, complement inhibitors, immune-cell-targeted therapies, platelet desialylation, umbilical cord mesenchymal stem cell therapy, and chimeric antigen receptor T cell immunotherapy, have shown good therapeutic potential. By targeting specific pathways in the pathogenesis of CITP, these novel therapies aim to achieve individualized precision treatment, thereby providing patients with more effective therapeutic options. This article reviews the pathogenesis, second-line treatment approaches, and therapeutic advances in CITP.