慢性乙型肝炎功能性治愈离完全治愈还有多远?
DOI: 10.12449/JCH250103
-
摘要: 功能性治愈是目前国内外慢性乙型肝炎的理想抗病毒治疗终点,其外周血HBsAg清除及HBV DNA检测不到并维持24周以上,标志着HBV感染的消退。然而,针对HBsAg清除后的肝内HBV标志物特点尚未有系统性描述。本文针对慢性乙型肝炎功能性治愈的最新定义、血清HBsAg清除后的肝内病毒学标志物特征、血清HBsAg高敏检测意义及低水平HBsAg是否需要治疗等问题等进行阐述,以期提高临床医生对慢性乙型肝炎功能性治愈的认识。Abstract: Functional cure is currently the ideal treatment endpoint for chronic hepatitis B (CHB) in China and globally. HBsAg seroclearance and HBV DNA that cannot be detected in peripheral blood for more than 24 weeks marks the regression of hepatitis B virus (HBV) infection. However, there is still a lack of systematic description of the characteristics of intrahepatic HBV markers after HBsAg seroclearance. This article elaborates on the issues including the latest definition of functional cure, the characteristics of intrahepatic virological markers after HBsAg seroclearance, the significance of ultrasensitive serum HBsAg detection, and antiviral therapy for CHB patients with a low level of HBsAg, so as to improve the understanding of functional cure among clinicians.
-
Key words:
- Hepatitis B, Chronic /
- Functional Cure /
- Hepatitis B Surface Antigens /
- DNA, Viral
-
大多数肝癌患者起病隐匿,诊断时已为晚期,失去根治性治疗机会,预后较差[1]。在全球Ⅲ期临床试验IMbrave 150中,阿替利珠单抗联合贝伐珠单抗(T+A方案)在不可切除肝细胞癌患者的一线治疗中的总生存期(overall survival,OS)和无进展生存期(progression-free survival,PFS)优于索拉非尼[2]。同样,在中国进行的多中心研究ORIENT-32表明,在不可切除的原发性肝癌患者中,信迪利单抗联合贝伐珠单抗类似物(双达方案)作为一线治疗的OS和PFS也显著优于索拉非尼[3]。基于上述研究,免疫检查点抑制剂联合抗血管生成治疗已成为不可切除肝癌的一线治疗标准,但客观缓解率仅有30%左右,远期生存率也有待提高[4-5]。
局部治疗对于控制病灶及改善长期生存均有较好疗效,目前立体定向放疗(stereotactic body radiotherapy,SBRT)已成为肝癌局部治疗的有效手段之一,与靶免方案的联合治疗也取得较好效果[6-7]。从机制上来看,放疗不仅可以造成肿瘤细胞DNA的直接损伤,还能导致肿瘤抗原释放,激活机体主动免疫,从而增强肿瘤免疫治疗效果[8]。抗血管生成治疗可以使肿瘤血管系统正常化,改善肿瘤微环境,从而提高放疗效果[9]。因此,SBRT联合双达方案的三联治疗从理论上可以改善不可切除肝癌患者的预后,但相关治疗效果、不良反应以及疗效预测指标鲜有报道。
本研究回顾性分析接受SBRT联合双达方案治疗的不可切除肝癌患者资料,评估预后及不良反应,探索预后预测指标,为该方案的治疗管理提供参考。
1. 资料和方法
1.1 研究对象
纳入2022年3月—12月在本中心放射治疗科接受SBRT联合双达方案治疗的不可切除肝癌患者42例。纳入标准:(1)经病理组织学确诊或符合临床诊断标准的原发性肝癌患者;(2)巴塞罗那分期为B或C期;(3)ECOG评分为0或1分;(4)治疗前基线AFP>40 mAU/mL;(5)根据改良实体瘤评价标准,至少有1处肝内可测量病灶。排除标准:(1)既往进行过抗肿瘤治疗;(2)双达方案治疗小于2个周期;(3)合并其他恶性肿瘤;(4)治疗后影像学或实验室数据缺失。
1.2 治疗方案
1.2.1 SBRT
本科室采用SBRT设备射波刀(美国Accuracy公司的VSI Cyberknife)。所有患者治疗前在CT引导下植入金标3~5枚,5~7天后于CT模拟机(somatom40排CT,德国Siemens公司)下行放疗定位。以CT模拟机平扫影像为基准图像,MR(Philips Ingenia MR-RT 3.0T,瑞士Royal Dutch Philips Electronics Ltd公司)增强影像为辅助图像,定位完成后将图像传至TPS系统(MultiPlan4.0系统,美国Accuracy公司)。放疗专科医生勾画相应肿瘤靶区和危及器官。大体肿瘤靶区基础上外扩3~5 mm为计划靶区,根据正常器官限量制定治疗计划,参照《AAPM TG101报告》[10]。SBRT剂量及分割模式主要取决于肝功能和正常器官剂量限制,也与病灶的大小、数量和位置等有关。给予处方剂量为36~50 Gy,分5~6次,连续照射。
1.2.2 双达方案
患者在完成放疗1周后接受信迪利单抗联合贝伐珠单抗治疗,具体剂量为:信迪利单抗200 mg,静脉滴注,每3周1次;贝伐珠单抗10 mg/kg,静脉滴注,每3周1次。双达方案一直使用到出现疾病进展或无法耐受的严重不良反应。
1.3 随访和评估
首次随访时间为治疗后6~8周,此后每6~8周随访1次。随访时检查血常规、肝功能、凝血功能、血清肿瘤标志物、上腹部增强CT或磁共振成像以及肺部CT,以评估肿瘤缓解。必要时进行PET-CT检查以确认是否肝外转移。主要终点为OS[定义为从SBRT开始日期至全因死亡日期或末次随访日期(2024年5月30日)的时间]以及PFS[定义为从SBRT开始日期至首次检测到影像学进展或全因死亡日期的时间]。次要终点为客观缓解率(objective response rate,ORR)和疾病控制率(disease control rate,DCR),根据mRECIST标准将肿瘤缓解分为完全缓解(complete remission,CR)、部分缓解(partial response,PR)、疾病稳定(stable disease,SD)和疾病进展(progressive disease,PD),并由2名经验丰富的放射科医生独立评价。ORR定义为获得CR+PR患者的百分比,DCR定义为获得CR+PR+SD患者的百分比。AFP应答定义为治疗后6~8周AFP下降大于50%。根据不良事件通用术语标准5.0版评估不良事件。
1.4 统计学方法
所有数据的统计分析使用SPSS 26.0或Graphpad Prism进行。通过Kaplan-Meier法和Log-rank检验估计生存率并进行比较;使用Cox比例风险模型估计HR和95%CI,在单变量模型中P<0.1的变量纳入多变量分析。P<0.05为差异有统计学意义。
2. 结果
2.1 一般资料
42例接受SBRT联合双达方案治疗的晚期肝癌患者中男39例,占比92.8%。>50岁的患者31例(73.8%),既往存在HBV感染41例(97.6%),肿瘤病灶最大径>5 cm有28例(66.6%),存在门静脉癌栓(portal vein tumor thrombus,PVTT)36例(85.8%),发生肝外转移8例(19.1%),提示入组患者肿瘤负荷相对较重。入组患者治疗前AFP均升高,中位值为626.5 ng/mL(表1)。42例患者均为初治,既往未行抗肿瘤治疗,此次接受SBRT剂量中位值为45 Gy,具体放疗剂量分割方案如下:36 Gy/6 Fx的患者有2例(4.7%),48 Gy/6 Fx有8例(19%),40 Gy/5 Fx有2例(4.7%),45 Gy/5 Fx有23例(54.7%),50 Gy/5 Fx有7例(16.6%)。
表 1 42例患者基线临床资料Table 1. The characteristics of 42 patients指标 数值 年龄[例(%)] ≤50岁 11(26.2) >50岁 31(73.8) 性别[例(%)] 男 39(92.8) 女 3(7.2) 慢性肝疾病[例(%)] 乙型肝炎 41(97.6) 其他 1(2.4) PVTT[例(%)] 有 36(85.8) 无 6(14.2) 肿瘤最大径[例(%)] ≤5 cm 14(33.4) >5 cm 28(66.6) 肝外转移[例(%)] 有 8(19.1) 无 34(80.9) ECOG评分[例(%)] 0分 35(83.3) 1分 7(16.7) Child-Pugh分级[例(%)] A级 26(61.9) B级 16(38.1) ALBI分级[例(%)] 1级 8(19.1) 2级 34(80.9) BCLC分期[例(%)] B期 1(2.3) C期 41(97.7) AFP(ng/mL) 626.5(83.1~4 105.0) 放疗剂量(Gy) 45(45~48) 2.2 肿瘤控制及远期生存情况
随访至2024年5月30日,共有21例患者死亡,其中8例因肝衰竭死亡,7例因肿瘤进展死亡,4例因继发感染死亡,2例因消化道出血死亡。在肿瘤局部控制方面,治疗后6例患者(14.3%)达到CR,23例患者(54.7%)达到PR,7例患者(16.7%)为SD,6例患者(14.3%)为PD,全组患者ORR为69%,DCR为85.7%(图1)。中位随访时间为21.6个月(95%CI:20.4~22.8),中位PFS为10.0个月(95%CI:6.7~13.0)(图2a),中位OS为23.3个月(95%CI:14.7~31.8)(图2b)。
2.3 影响预后的因素
影响患者预后的单因素分析见表2,治疗后6~8周出现AFP应答的患者有25例,多因素分析结果显示AFP应答与患者良好的预后相关(HR=0.31,95%CI:0.13~0.75,P=0.009);AFP应答组中位OS显著优于AFP未应答组(未达到 vs 11.8个月,P=0.007)(图3)。
表 2 影响OS的单因素分析Table 2. Univariate analysis for factors affecting OS临床特征 HR(95%CI) P值 年龄(≤50岁/>50岁) 0.33(0.10~1.13) 0.077 性别(女/男) 0.74(0.10~5.50) 0.764 门静脉侵犯(无/有) 0.24(0.03~1.79) 0.163 肿瘤大小(≤5 cm/>5 cm) 1.25(0.52~3.01) 0.617 肝外转移(有/无) 1.03(0.35~3.08) 0.953 Child-Pugh分级(A级/B级) 0.53(0.22~1.24) 0.144 ALBI分级(1级/2级) 0.88(0.30~2.62) 0.818 AFP应答(是/否) 0.32(0.14~0.78) 0.011 门静脉侵犯(无/有) 1.11(0.61~2.03) 0.725 用药周期 0.96(0.91~1.01) 0.086 放疗剂量(Gy) 0.99(0.88~1.12) 0.912 ECOG评分(1分/0分) 0.75(0.25~2.26) 0.614 2.4 不良反应
42例患者均未发生非预期不良反应或治疗相关死亡,不良反应多为1~2级,其中血液系统不良反应较常见,发生白细胞减少10例(23.8%),血小板减少8例(19.0%),1例患者出现3级血小板减少,给予重组人血小板生成素后血小板恢复正常水平。10例患者(23.8%)出现转氨酶升高,给予保肝药物对症治疗,未进一步恶化。10例患者出现低蛋白血症,放疗结束1月内可缓解。3例患者出现免疫相关性甲状腺功能减退,4例患者发生免疫相关性皮疹,均为1~2级,未使用激素及免疫抑制剂等药物干预,持续时间4~10天,未影响后续治疗(表3)。
表 3 治疗相关不良反应Table 3. Treatment-related adverse events不良反应 所有级别[例(%)] 3~4级[例(%)] 白细胞减少 10(23.8) 0(0.0) 血小板减少 8(19.0) 1(2.4) 高血压 2(4.8) 0(0.0) 恶心呕吐 3(7.1) 0(0.0) 消化道出血 1(2.4) 0(0.0) 蛋白尿 3(7.1) 0(0.0) 腹水 9(21.4) 1(2.4) 转氨酶升高 10(23.8) 0(0.0) 肾功能不全 1(2.4) 0(0.0) 高胆红素 4(9.5) 0(0.0) 低蛋白血症 10(23.8) 1(2.4) 免疫相关性甲状腺功能减退 3(7.1) 0(0.0) 免疫相关性皮疹 4(9.5) 0(0.0) 3. 讨论
在目前的临床诊疗中,免疫联合抗血管生成治疗已成为晚期肝细胞癌的一线标准方案,但ORR仅有30%左右,亟待提高[11-12]。随着放疗技术的进展,放疗不仅可导致肿瘤细胞DNA双链断裂,还能诱导免疫原性细胞死亡,刺激全身抗肿瘤免疫[13]。抗血管生成治疗可通过使肿瘤血管正常化,形成免疫友好的肿瘤微环境来增强放疗的功效[9]。此外,免疫治疗可以克服放疗导致肿瘤表面PD-L1表达增加、抑制性免疫细胞功能增强等负面作用,从而增强放疗的协同效率[14]。这为放疗联合免疫及抗血管生成治疗提供了坚实的理论依据。
既往回顾性研究分析了放疗联合靶免的治疗方案,Su等[15]研究发现,PD-1抑制剂与抗血管药物联合调强放疗的ORR为42.6%,Wang等[6]报道的SBRT联合仑伐替尼和PD-1抑制剂的ORR可达到63%。一项前瞻性多中心Ⅱ期临床研究显示,放疗联合双达方案的ORR为58.7%,中位PFS为13.8个月,中位OS为24.0个月[16]。与上述前瞻性研究不同,本研究放疗在双达方案之前,患者ORR为69%,与单独双达方案以及上述前瞻性研究相比均有提升,中位OS与前瞻性研究结果相当。在双达方案之前进行SBRT或许具有协同效应,可获得较好的局部缓解及生存结局,本研究为该三联疗法的可行性和安全性提供了临床证据。
本研究入组患者中有36例(85.8%)存在PVTT,通常与不良预后相关[17]。但由于PVTT细胞对辐射的敏感性较高,SBRT已被证明在控制PVTT方面疗效显著[18]。一方面,放疗使癌栓收缩有助于恢复部分门静脉血流,可改善肝功能;另一方面,PVTT的控制能消除部分侵入血流的肿瘤细胞,进而减少了血行转移,产生较好的肿瘤反应和生存结局[19]。除此之外,在双达方案之前使用SBRT可以有效降低肝脏肿瘤负荷,改善肝功能,提高患者对后续治疗的耐受性,从而接受更多周期的双达方案维持治疗,这可能是本组患者预后良好的原因之一。
在预后指标的探索方面,AFP是一种与肿瘤负荷和生物学行为相关的生物标志物,数十年来在肝癌领域发挥着重要作用[20]。当前指南推荐AFP与超声联合,用于肝癌高危人群的早期筛查[21]。此外,AFP易于在随访期间重复检测,可评估其动态变化来监测治疗效果[22]。目前关于AFP应答的临界值尚无定论,国内外研究多为主观定义。一项Meta分析显示,AFP应答的定义为AFP水平下降20%或50%所占比例居多,且该研究提示与AFP水平下降50%的临界值相比,AFP水平下降20%对OS和PFS的预测效果更好,但倾向于仅接受靶向治疗的患者[23]。Shao等[24]将早期AFP应答定义为治疗后4周下降超过20%,这与晚期肝癌免疫治疗较好的预后有关。另一项研究表明在接受T+A方案治疗的晚期肝癌患者中,治疗第6周时AFP较基线降低≥75%或升高≤10%的患者均具有较长的PFS及OS[25]。本研究参考入组患者AFP水平下降比例的中位值,将SBRT联合双达治疗后6~8周AFP水平下降>50%定义为AFP应答,多因素分析提示AFP应答是患者OS的独立影响因素。AFP应答可辅助影像学评估,有助于更好地识别该三联疗法中疗效显著的患者,并对疗效不佳患者及时调整治疗方案。但是,对于不同AFP初始值的肝癌患者,AFP应答的预测价值是否一致仍未知,且关于判断AFP应答的最佳时间窗目前亦无定论。在未来的探索中,需要更多高质量的前瞻性研究对AFP给予更多关注。
本研究也证实了SBRT联合双达方案治疗的安全性,双达方案治疗最常见的不良反应为蛋白尿、血小板减少、转氨酶升高、高血压和甲状腺功能减退等[3],与本研究不良反应相似,治疗期间未发生导致停药或死亡的不良事件。本研究中所采用的射波刀特有的呼吸追踪系统有效降低了照射过程中肝脏位移带来的肝损伤。另一方面以肿瘤为中心,剂量梯度衰减也使得周围组织所受照射剂量更低。总之,不良反应主要集中在1~2级,SBRT与双达方案联合产生协同毒性的可能性较小。
综上所述,SBRT联合双达方案治疗晚期肝癌可改善生存且安全性可控,治疗后6~8周AFP水平下降>50%与预后良好相关。但本研究为回顾性研究,样本量相对较少,未来仍需开展前瞻性的随机、对照、多中心临床研究,进一步验证结论。
-
表 1 CHB功能性治愈定义的更新
Table 1. Updated definition of functional cure
临床指标 完全治愈[8] CHB功能性治愈(2019)[9] CHB功能性治愈(2022)[8] 部分治愈(2022)[8] HBsAg定量 1) 阴性 低于检测下限 低于检测下限 <100 IU/mL 3) 抗-HBs 阳性/阴性 阳性/阴性 阳性/阴性 阴性 HBeAg 阴性 阴性 阴性 阴性 抗-HBe 阳性 阳性 阳性 阳性 HBV DNA2) 靶标未检测到 靶标未检测到 低于检测下限 低于检测下限 ALT 恢复正常 恢复正常 恢复正常 恢复正常 cccDNA 不存在 存在 存在 存在 HBV整合 不存在 存在 存在 存在 肝组织学改变 有 有 有 不详 临床预后 改善 改善 改善 改善 肝癌残留风险 极低 极低 极低 极低 持久性 有 有 有 有 血清HBsAg间隔24周检测 未详细定义 未详细定义 是 是 注:1) HBsAg低于检测下限,检测下限值为0.05 IU/mL;2) HBV DNA低于检测下限,检测下限值为10 IU/mL;3)仍需前瞻性临床研究进一步确定HBsAg<100 IU/mL是否为具有临床意义的部分治愈阈值。
-
[1] WHO. World health statistics 2022: monitoring health for the SDGs, sustainable development goals[M]. Geneva: World Health Organization, 2022. [2] JENG WJ, PAPATHEODORIDIS GV, LOK A. Hepatitis B[J]. Lancet, 2023, 401( 10381): 1039- 1052. DOI: 10.1016/S0140-6736(22)01468-4. [3] Chinese Society of Infectious Disease, Chinese Society of Hepatology, Chinese Medical Association. The expert consensus on functional cure of chronic hepatitis B[J]. J Clin Hepatol, 2019, 35( 8): 1693- 1701. DOI: 10.3969/j.issn.1001-5256.2019.08.008.中华医学会感染病学分会, 中华医学会肝病学分会. 慢性乙型肝炎临床治愈(功能性治愈)专家共识[J]. 临床肝胆病杂志, 2019, 35( 8): 1693- 1701. DOI: 10.3969/j.issn.1001-5256.2019.08.008. [4] LI MH, SUN FF, BI XY, et al. Consolidation treatment needed for sustained HBsAg-negative response induced by interferon-alpha in HBeAg positive chronic hepatitis B patients[J]. Virol Sin, 2022, 37( 3): 390- 397. DOI: 10.1016/j.virs.2022.03.001. [5] GAO N, YU HY, ZHANG J, et al. Role of hepatitis B surface antibody in seroreversion of hepatitis B surface antigen in patients achieving hepatitis B surface antigen loss with pegylated interferon-based therapy[J]. J Viral Hepat, 2022, 29( 10): 899- 907. DOI: 10.1111/jvh.13734. [6] HUANG D, WU D, WANG P, et al. End-of-treatment HBcrAg and HBsAb levels identify durable functional cure after Peg-IFN-based therapy in patients with CHB[J]. J Hepatol, 2022, 77( 1): 42- 54. DOI: 10.1016/j.jhep.2022.01.021. [7] LOK AS, ZOULIM F, DUSHEIKO G, et al. Durability of hepatitis B surface antigen loss with nucleotide analogue and peginterferon therapy in patients with chronic hepatitis B[J]. Hepatol Commun, 2019, 4( 1): 8- 20. DOI: 10.1002/hep4.1436. [8] GHANY MG, BUTI M, LAMPERTICO P, et al. Guidance on treatment endpoints and study design for clinical trials aiming to achieve cure in chronic hepatitis B and D: report from the 2022 AASLD-EASL HBV-HDV treatment endpoints conference[J]. J Hepatol, 2023, 79( 5): 1254- 1269. DOI: 10.1016/j.jhep.2023.06.002. [9] CORNBERG M, LOK AS, TERRAULT NA, et al. Guidance for design and endpoints of clinical trials in chronic hepatitis B-report from the 2019 EASL-AASLD HBV treatment endpoints conference(double dagger)[J]. J Hepatol, 2020, 72( 3): 539- 557. DOI: 10.1016/j.jhep.2019.11.003. [10] YIP TCF, WONG GLH, CHAN HLY, et al. HBsAg seroclearance further reduces hepatocellular carcinoma risk after complete viral suppression with nucleos(t)ide analogues[J]. J Hepatol, 2019, 70( 3): 361- 370. DOI: 10.1016/j.jhep.2018.10.014. [11] XIE C, XIE D, XU Q, et al. The everest project's 5-year update: efficacy of PEG-IFNα therapy in NA-suppressed HBeAg negative CHB[R]. Kyoto: APASL, 2024. [12] HU P, SHANG J, ZHANG WH, et al. HBsAg loss with peg-interferon Alfa-2a in hepatitis B patients with partial response to nucleos(t)ide analog: New switch study[J]. J Clin Transl Hepatol, 2018, 6( 1): 25- 34. DOI: 10.14218/JCTH.2017.00072. [13] VITTAL A, SHARMA D, HU A, et al. Systematic review with meta-analysis: The impact of functional cure on clinical outcomes in patients with chronic hepatitis B[J]. Aliment Pharmacol Ther, 2022, 55( 1): 8- 25. DOI: 10.1111/apt.16659. [14] HU Y, YE YZ, YE LJ, et al. Efficacy and safety of interferon alpha-2b versus pegylated interferon alpha-2a monotherapy in children with chronic hepatitis B: A real-life cohort study from Shanghai, China[J]. World J Pediatr, 2019, 15( 6): 595- 600. DOI: 10.1007/s12519-019-00303-w. [15] ZHONG WT, YAN LZ, ZHU YG, et al. A high functional cure rate was induced by pegylated interferon alpha-2b treatment in postpartum hepatitis B e antigen-negative women with chronic hepatitis B virus infection: An exploratory study[J]. Front Cell Infect Microbiol, 2024, 14: 1426960. DOI: 10.3389/fcimb.2024.1426960. [16] TU T, BUDZINSKA MA, VONDRAN FWR, et al. Hepatitis B virus DNA integration occurs early in the viral life cycle in an in vitro infection model via sodium taurocholate cotransporting polypeptide-dependent uptake of enveloped virus particles[J]. J Virol, 2018, 92( 11): e02007-17. DOI: 10.1128/JVI.02007-17. [17] TU T, BUDZINSKA MA, SHACKEL NA, et al. HBV DNA integration: Molecular mechanisms and clinical implications[J]. Viruses, 2017, 9( 4): 75. DOI: 10.3390/v9040075. [18] TU T, ZEHNDER B, QU BQ, et al. De novo synthesis of hepatitis B virus nucleocapsids is dispensable for the maintenance and transcriptional regulation of cccDNA[J]. JHEP Rep, 2020, 3( 1): 100195. DOI: 10.1016/j.jhepr.2020.100195. [19] CHUA CG, MEHROTRA A, MAZZULLI T, et al. Optimized ex vivo stimulation identifies multi-functional HBV-specific T cells in a majority of chronic hepatitis B patients[J]. Sci Rep, 2020, 10( 1): 11344. DOI: 10.1038/s41598-020-68226-5. [20] MASON WS, GILL US, LITWIN S, et al. HBV DNA integration and clonal hepatocyte expansion in chronic hepatitis B patients considered immune tolerant[J]. Gastroenterology, 2016, 151( 5): 986- 998. e 4. DOI: 10.1053/j.gastro.2016.07.012. [21] MEIER MA, CALABRESE D, SUSLOV A, et al. Ubiquitous expression of HBsAg from integrated HBV DNA in patients with low viral load[J]. J Hepatol, 2021, 75( 4): 840- 847. DOI: 10.1016/j.jhep.2021.04.051. [22] RINGLANDER J, SKOGLUND C, PRAKASH K, et al. Deep sequencing of liver explant transcriptomes reveals extensive expression from integrated hepatitis B virus DNA[J]. J Viral Hepat, 2020, 27( 11): 1162- 1170. DOI: 10.1111/jvh.13356. [23] TU T, ZHANG H, URBAN S. Hepatitis B virus DNA integration: in vitro models for investigating viral pathogenesis and persistence[J]. Viruses, 2021, 13( 2): 180. DOI: 10.3390/v13020180. [24] VAILLANT A. HBsAg, subviral particles, and their clearance in establishing a functional cure of chronic hepatitis B virus infection[J]. ACS Infect Dis, 2021, 7( 6): 1351- 1368. DOI: 10.1021/acsinfecdis.0c00638. [25] THIBAULT V, SERVANT-DELMAS A, LY TD, et al. Performance of HBsAg quantification assays for detection of hepatitis B virus genotypes and diagnostic escape-variants in clinical samples[J]. J Clin Virol, 2017, 89: 14- 21. DOI: 10.1016/j.jcv.2017.02.001. [26] YAN Y, SUN HZ, CHANG L, et al. Circulating immune complexes and mutations of HBsAg are associated with the undetectable HBsAg in anti-HBs and HBeAg positive occult hepatitis B virus infection[J]. Front Microbiol, 2022, 13: 1063616. DOI: 10.3389/fmicb.2022.1063616. [27] ANDERSON M, HOLZMAYER V, STEC M, et al. Ultrasensitive HBsAg testing predicts HBsAg seroreversion outcomes: Considerations for new and existing therapies[J]. J Hepatol, 2024, 81( 1): e24- e25. DOI: 10.1016/j.jhep.2023.11.018. [28] WONG DKH, CHEN C, MAK LY, et al. Detection of the hepatitis B surface antigen in patients with occult hepatitis B by use of an assay with enhanced sensitivity[J]. J Clin Microbiol, 2022, 60( 2): e0220421. DOI: 10.1128/jcm.02204-21. [29] KUSUMOTO S, TANAKA Y, SUZUKI R, et al. Ultra-high sensitivity HBsAg assay can diagnose HBV reactivation following rituximab-based therapy in patients with lymphoma[J]. J Hepatol, 2020, 73( 2): 285- 293. DOI: 10.1016/j.jhep.2020.03.009. [30] GHANY MG, BUTI M, LAMPERTICO P, et al. Reply to:“ultrasensitive HBsAg testing predicts HBsAg seroreversion outcomes: Considerations for new and existing therapies”[J]. J Hepatol, 2024, 81( 1): e26- e27. DOI: 10.1016/j.jhep.2024.03.001. [31] MAK LY, WONG DKH, POLLICINO T, et al. Occult hepatitis B infection and hepatocellular carcinoma: Epidemiology, virology, hepatocarcinogenesis and clinical significance[J]. J Hepatol, 2020, 73( 4): 952- 964. DOI: 10.1016/j.jhep.2020.05.042. [32] XIANG KH, MICHAILIDIS E, DING H, et al. Effects of amino acid substitutions in hepatitis B virus surface protein on virion secretion, antigenicity, HBsAg and viral DNA[J]. J Hepatol, 2017, 66( 2): 288- 296. DOI: 10.1016/j.jhep.2016.09.005. [33] DEGUCHI M, YAMASHITA N, KAGITA M, et al. Quantitation of hepatitis B surface antigen by an automated chemiluminescent microparticle immunoassay[J]. J Virol Methods, 2004, 115( 2): 217- 222. DOI: 10.1016/j.jviromet.2003.10.002. [34] LEE HJ, KIM SY, LEE SM, et al. Elecsys hepatitis B surface antigen quantitative assay: Performance evaluation and correlation with hepatitis B virus DNA during 96 weeks of follow-up in chronic hepatitis B patients[J]. Ann Lab Med, 2012, 32( 6): 420- 425. DOI: 10.3343/alm.2012.32.6.420. [35] THIBAULT V, LAPERCHE S, AKHAVAN S, et al. Impact of hepatitis B virus genotypes and surface antigen variants on the performance of HBV real time PCR quantification[J]. J Virol Methods, 2009, 159( 2): 265- 270. DOI: 10.1016/j.jviromet.2009.04.014. [36] VERHEYEN J, NEUMANN-FRAUNE M, BERG T, et al. The detection of HBsAg mutants expressed in vitro using two different quantitative HBsAg assays[J]. J Clin Virol, 2012, 54( 3): 279- 281. DOI: 10.1016/j.jcv.2012.04.010. [37] WILKINSON DE, SEIZ PL, SCHÜTTLER CG, et al. International collaborative study on the 3rd WHO International Standard for hepatitis B surface antigen[J]. J Clin Virol, 2016, 82: 173- 180. DOI: 10.1016/j.jcv.2016.06.003. [38] WANG ZL, ZHENG JR, YANG RF, et al. An ideal hallmark closest to complete cure of chronic hepatitis B patients: High-sensitivity quantitative HBsAg loss[J]. J Clin Transl Hepatol, 2023, 11( 1): 197- 206. DOI: 10.14218/JCTH.2022.00289. [39] PFEFFERKORN M, BÖHM S, SCHOTT T, et al. Quantification of large and middle proteins of hepatitis B virus surface antigen(HBsAg) as a novel tool for the identification of inactive HBV carriers[J]. Gut, 2018, 67( 11): 2045- 2053. DOI: 10.1136/gutjnl-2017-313811. [40] LIN X, ZHENG YH, LI H, et al. Serum hepatitis B virus large and medium surface proteins as novel tools for predicting HBsAg clearance[J]. Front Immunol, 2022, 13: 1028921. DOI: 10.3389/fimmu.2022.1028921. [41] PFEFFERKORN M, SCHOTT T, BÖHM S, et al. Composition of HBsAg is predictive of HBsAg loss during treatment in patients with HBeAg-positive chronic hepatitis B[J]. J Hepatol, 2021, 74( 2): 283- 292. DOI: 10.1016/j.jhep.2020.08.039. [42] PFEFFERKORN M, van BÖMMEL F. Commentary: Serum hepatitis B virus large and medium surface proteins as novel tools for predicting HBsAg clearance[J]. Front Immunol, 2022, 13: 1081730. DOI: 10.3389/fimmu.2022.1081730. [43] LU JH, YANG L, ZHAO ZX, et al. Comparative study of high? sensitivity and conventional fluorescence quantitative PCR in the monitoring of antiviral efficacy in patients with chronic hepatitis B[J]. J Mol Diagn Ther, 2019, 11( 5): 361- 364. DOI: 10.3969/j.issn.1674-6929.2019.05.005.卢建华, 杨莉, 赵召霞, 等. 高敏与普通荧光定量PCR技术在慢乙肝患者抗病毒疗效监测中的对比研究[J]. 分子诊断与治疗杂志, 2019, 11( 5): 361- 364. DOI: 10.3969/j.issn.1674-6929.2019.05.005. [44] FENG B, ZHENG JR, WANG ZL. Clinical value of highly sensitive hepatitis B virus surface antigen and DNA assays[J]. Chin J Lab Med, 2023, 46( 1): 7- 11. DOI: 10.3760/cma.j.cn114452-20220817-00475.封波, 郑佳睿, 王资隆. 高灵敏乙型肝炎病毒表面抗原和DNA检测的临床应用价值[J]. 中华检验医学杂志, 2023, 46( 1): 7- 11. DOI: 10.3760/cma.j.cn114452-20220817-00475. [45] INOUE T, KUSUMOTO S, IIO E, et al. Clinical efficacy of a novel, high-sensitivity HBcrAg assay in the management of chronic hepatitis B and HBV reactivation[J]. J Hepatol, 2021, 75( 2): 302- 310. DOI: 10.1016/j.jhep.2021.02.017. [46] WONG DKH, HUANG FY, LAI CL, et al. Occult hepatitis B infection and HBV replicative activity in patients with cryptogenic cause of hepatocellular carcinoma[J]. Hepatology, 2011, 54( 3): 829- 836. DOI: 10.1002/hep.24551. [47] GAO N, GUAN GW, XU GL, et al. Integrated HBV DNA and cccDNA maintain transcriptional activity in intrahepatic HBsAg-positive patients with functional cure following PEG-IFN-based therapy[J]. Aliment Pharmacol Ther, 2023, 58( 10): 1086- 1098. DOI: 10.1111/apt.17670. [48] YU XQ, GONG QM, YU DM, et al. Spatial transcriptomics reveals a low extent of transcriptionally active hepatitis B virus integration in patients with HBsAg loss[J]. Gut, 2024, 73( 5): 797- 809. DOI: 10.1136/gutjnl-2023-330577. [49] NARMADA BC, KHAKPOOR A, SHIRGAONKAR N, et al. Single-cell landscape of functionally cured chronic hepatitis B patients reveals activation of innate and altered CD4-CTL-driven adaptive immunity[J]. J Hepatol, 2024, 81( 1): 42- 61. DOI: 10.1016/j.jhep.2024.02.017. [50] GU ZQ, JIANG QQ, ABULAITI A, et al. Hepatitis B virus enhancer 1 activates preS1 and preS2 promoters of integrated HBV DNA impairing HBsAg secretion[J]. JHEP Rep, 2024, 6( 9): 101144. DOI: 10.1016/j.jhepr.2024.101144. [51] LIANG YJ, TENG W, CHEN CL, et al. Clinical implications of HBV PreS/S mutations and the effects of PreS2 deletion on mitochondria, liver fibrosis, and cancer development[J]. Hepatology, 2021, 74( 2): 641- 655. DOI: 10.1002/hep.31789. [52] MICHLER T, ZILLINGER J, HAGEN P, et al. The lack of HBsAg secretion does neither facilitate induction of antiviral T cell responses nor hepatitis B virus clearance in mice[J]. Antiviral Res, 2024, 226: 105896. DOI: 10.1016/j.antiviral.2024.105896. [53] YANG SS, ZENG WJ, ZHANG JM, et al. Restoration of a functional antiviral immune response to chronic HBV infection by reducing viral antigen load: If not sufficient, is it necessary?[J]. Emerg Microbes Infect, 2021, 10( 1): 1545- 1554. DOI: 10.1080/22221751.2021.1952851. [54] WERLE-LAPOSTOLLE B, BOWDEN S, LOCARNINI S, et al. Persistence of cccDNA during the natural history of chronic hepatitis B and decline during adefovir dipivoxil therapy[J]. Gastroenterology, 2004, 126( 7): 1750- 1758. DOI: 10.1053/j.gastro.2004.03.018. [55] CHEVALIEZ S, HÉZODE C, BAHRAMI S, et al. Long-term hepatitis B surface antigen(HBsAg) kinetics during nucleoside/nucleotide analogue therapy: Finite treatment duration unlikely[J]. J Hepatol, 2013, 58( 4): 676- 683. DOI: 10.1016/j.jhep.2012.11.039. [56] HUANG Q, ZHOU B, CAI DW, et al. Rapid turnover of hepatitis B virus covalently closed circular DNA indicated by monitoring emergence and reversion of signature-mutation in treated chronic hepatitis B patients[J]. Hepatology, 2021, 73( 1): 41- 52. DOI: 10.1002/hep.31240. [57] LU FM, FENG B, ZHENG SJ, et al. Current status of the research on low-level viremia in chronic hepatitis B patients receiving nucleos(t)ide analogues[J]. J Clin Hepatol, 2021, 37( 6): 1268- 1274. DOI: 10.3969/j.issn.1001-5256.2021.06.007.鲁凤民, 封波, 郑素军, 等. 核苷(酸)类似物经治的慢性乙型肝炎患者低病毒血症的研究现状[J]. 临床肝胆病杂志, 2021, 37( 6): 1268- 1274. DOI: 10.3969/j.issn.1001-5256.2021.06.007. [58] ALLWEISS L, VOLZ T, GIERSCH K, et al. Proliferation of primary human hepatocytes and prevention of hepatitis B virus reinfection efficiently deplete nuclear cccDNA in vivo[J]. Gut, 2018, 67( 3): 542- 552. DOI: 10.1136/gutjnl-2016-312162. [59] WANG Y, LI YM, ZAI WJ, et al. HBV covalently closed circular DNA minichromosomes in distinct epigenetic transcriptional states differ in their vulnerability to damage[J]. Hepatology, 2022, 75( 5): 1275- 1288. DOI: 10.1002/hep.32245. [60] MICHLER T, KOSINSKA AD, FESTAG J, et al. Knockdown of virus antigen expression increases therapeutic vaccine efficacy in high-titer hepatitis B virus carrier mice[J]. Gastroenterology, 2020, 158( 6): 1762- 1775. e 9. DOI: 10.1053/j.gastro.2020.01.032. [61] IANNACONE M, GUIDOTTI LG. Immunobiology and pathogenesis of hepatitis B virus infection[J]. Nat Rev Immunol, 2022, 22( 1): 19- 32. DOI: 10.1038/s41577-021-00549-4. [62] ZHENG PY, DOU YQ, WANG QY. Immune response and treatment targets of chronic hepatitis B virus infection: Innate and adaptive immunity[J]. Front Cell Infect Microbiol, 2023, 13: 1206720. DOI: 10.3389/fcimb.2023.1206720. [63] FAURE-DUPUY S, DELPHIN M, AILLOT L, et al. Hepatitis B virus-induced modulation of liver macrophage function promotes hepatocyte infection[J]. J Hepatol, 2019, 71( 6): 1086- 1098. DOI: 10.1016/j.jhep.2019.06.032. [64] GUAN GW, ZHANG T, NING J, et al. Higher TP53BP2 expression is associated with HBsAg loss in peginterferon-α-treated patients with chronic hepatitis B[J]. J Hepatol, 2024, 80( 1): 41- 52. DOI: 10.1016/j.jhep.2023.09.039. [65] CHEN HT, SUN J, ZHOU B, et al. Variants in STAT4 associated with cure of chronic HBV infection in HBeAg-positive patients treated with pegylated interferon-alpha[J]. Clin Gastroenterol Hepatol, 2020, 18( 1): 196- 204. e 8. DOI: 10.1016/j.cgh.2019.04.044. [66] WU TT, COATES L, ALDRICH CE, et al. In hepatocytes infected with duck hepatitis B virus, the template for viral RNA synthesis is amplified by an intracellular pathway[J]. Virology, 1990, 175( 1): 255- 261. DOI: 10.1016/0042-6822(90)90206-7. [67] ZOULIM F. New insight on hepatitis B virus persistence from the study of intrahepatic viral cccDNA[J]. J Hepatol, 2005, 42( 3): 302- 308. DOI: 10.1016/j.jhep.2004.12.015. [68] YUEN MF, AGARWAL K, GANE EJ, et al. Safety, pharmacokinetics, and antiviral effects of ABI-H0731, a hepatitis B virus core inhibitor: A randomised, placebo-controlled phase 1 trial[J]. Lancet Gastroenterol Hepatol, 2020, 5( 2): 152- 166. DOI: 10.1016/S2468-1253(19)30346-2. [69] YUEN MF, ZHOU X, GANE E, et al. Safety, pharmacokinetics, and antiviral activity of RO7049389, a core protein allosteric modulator, in patients with chronic hepatitis B virus infection: A multicentre, randomised, placebo-controlled, phase 1 trial[J]. Lancet Gastroenterol Hepatol, 2021, 6( 9): 723- 732. DOI: 10.1016/S2468-1253(21)00176-X. [70] CHENG DL, HAN B, ZHANG W, et al. Clinical effects of NTCP-inhibitor myrcludex B[J]. J Viral Hepat, 2021, 28( 6): 852- 858. DOI: 10.1111/jvh.13490. [71] WANG L, ZHU QH, ZHANG JD, et al. Discovery of a first-in-class orally available HBV cccDNA inhibitor[J]. J Hepatol, 2023, 78( 4): 742- 753. DOI: 10.1016/j.jhep.2022.12.014. [72] PONDÉ RAA, AMORIM GSP. Elimination of the hepatitis B virus: A goal, a challenge[J]. Med Res Rev, 2024, 44( 5): 2015- 2034. DOI: 10.1002/med.22030. [73] LIM SG, BAUMERT TF, BONI C, et al. The scientific basis of combination therapy for chronic hepatitis B functional cure[J]. Nat Rev Gastroenterol Hepatol, 2023, 20( 4): 238- 253. DOI: 10.1038/s41575-022-00724-5. [74] LEE MH, YANG HI, LIU J, et al. Prediction models of long-term cirrhosis and hepatocellular carcinoma risk in chronic hepatitis B patients: Risk scores integrating host and virus profiles[J]. Hepatology, 2013, 58( 2): 546- 554. DOI: 10.1002/hep.26385. [75] TSENG TC, LIU CJ, CHEN CL, et al. Risk stratification of hepatocellular carcinoma in hepatitis B virus e antigen-negative carriers by combining viral biomarkers[J]. J Infect Dis, 2013, 208( 4): 584- 593. DOI: 10.1093/infdis/jit209. [76] BRANCACCIO G, SALPINI R, PIERMATTEO L, et al. An increase in the levels of middle surface antigen characterizes patients developing HBV-driven liver cancer despite prolonged virological suppression[J]. Microorganisms, 2021, 9( 4): 752. DOI: 10.3390/microorganisms9040752. [77] SONNEVELD MJ, CHIU SM, PARK JY, et al. Probability of HBsAg loss after nucleo(s)tide analogue withdrawal depends on HBV genotype and viral antigen levels[J]. J Hepatol, 2022, 76( 5): 1042- 1050. DOI: 10.1016/j.jhep.2022.01.007. [78] TSENG CH, CHEN TH, WU JL, et al. Serious adverse events after cessation of nucleos(t)ide analogues in individuals with chronic hepatitis B: A systematic review and meta-analysis[J]. JHEP Rep, 2022, 5( 1): 100617. DOI: 10.1016/j.jhepr.2022.100617. [79] WEN CJ, WANG YX, TIAN HY, et al. Clinical cure induced by pegylated interferon α-2b in the advantaged population of chronic hepatitis B virus infection: A retrospective cohort study[J]. Front Cell Infect Microbiol, 2024, 13: 1332232. DOI: 10.3389/fcimb.2023.1332232. -