慢性乙型肝炎功能性治愈的定义是在停止抗病毒治疗后至少24周，HBsAg<0.05 IU/mL，血清HBV DNA<10 IU/mL。这需要抑制HBV复制、降低病毒抗原产生，同时恢复对HBV感染的免疫应答。约30%～50%接受核苷（酸）类似物治疗并经严格选择的慢性乙型肝炎患者，加用或单用聚乙二醇干扰素α治疗，或经核苷（酸）类似物有限疗程治疗后HBsAg<100 IU/mL者，可获得功能性治愈。目前有40余种新的抗HBV药物和免疫调节剂正在进行临床试验。抑制HBV复制、降低病毒抗原，以及提高HBV感染免疫应答药物的联合应用，可能是慢性乙型肝炎功能性治愈的理想治疗策略。但确定最佳的联合、用药时间、用药顺序和治疗期限等尚需进一步研究。

Functional cure of chronic hepatitis B （CHB） is defined as HBsAg<0.05 IU/mL and serum HBV DNA<10 IU/mL for at least 24 weeks after discontinuation of antiviral therapy. This requires suppression of HBV replication and reduction of viral antigen production， as well as restoration of immune response to HBV infection. About 30% — 50% of highly selected CHB patients treated with nucleos（t）ide analogues can achieve functional cure after add-on therapy or monotherapy with pegylated interferon-α or a finite course of treatment with nucleos（t）ide analogues among patients with HBsAg<100 IU/mL. At present， clinical trials are being conducted for more than 40 types of novel anti-HBV drugs and immunomodulators. The combination of drugs that inhibit viral replication， reduce antigen burden， and restore immune response to HBV infection may be an ideal strategy to achieve the functional cure of CHB. However， further studies are needed to determine the optimal drug combination， the timing and sequence of medication， and the duration of treatment.