Direct-acting antivirals (DAAs) play a critical role for the therapy of chronical hepatitis B. DAAs can decrease the production of viral progeny of hepatitis B virus (HBV), breaking the viral dynamic equilibrium between: (1) virion production from hepatocytes and clearance from circulation; (2) replenishment and decay of covalently closed circular (ccc)DNA pool inside infected hepatocytes. Nucleos(t)ide analogues can potently shift the first balance to undetectable viremia in the blood, but have limited or no effect on the second one, thus making it imperative to develop new agents targeting additional step(s) of HBV life cycle. We herein briefly introduce the DAAs currently in development by classifying them as agents affecting the replenishment or the decay of cccDNA pool.
直接抗病毒药物（DAAs），是治疗慢性乙型肝炎的重要手段。DAAs能直接干扰病毒的感染复制过程，减少子代病毒产率，继而影响体内乙型肝炎病毒（HBV）的两种动态平衡，即肝细胞中病毒复制-循环中病毒衰减之间的平衡，共价闭合环状DNA（cccDNA）池补充-cccDNA衰减之间的平衡。现有核苷（酸）类似物足以影响第一种平衡，却难以撼动第二种平衡。因此，靶向HBV感染复制的不同环节，开发新型DAAs十分必要。现从cccDNA池补充-cccDNA衰减这一平衡的两个方面，探讨近期DAAs研发的主要进展。.
Keywords: Covalently closed circular DNA; Direct-acting antiviralagents; Hepatitis B.