恩替卡韦耐药的慢性乙型肝炎患者序贯挽救治疗的临床疗效与病毒学演变分析

Analysis for clinical efficacy and virological evolution during sequential entecavir plus adefovir combination and tenofovir ± entecavir therapies in entecavir-resistant chronic hepatitis B patients

目的分析核苷(酸)类药物治疗失败并检出恩替卡韦(ETV)耐药突变的HBV感染患者恩替卡韦+阿德福韦酯(ETV+ADV)联合挽救治疗应答不佳、继续替诺福韦酯(TDF)±ETV挽救治疗期间的临床疗效与病毒学演变特点。方法从4例患者血清中扩增HBV反转录酶区基因,采用直接测序法检测和克隆测序法证实耐药突变。结合临床资料回顾性分析患者在序贯挽救治疗期间的病毒学动态演变特点及临床疗效。结果在ETV+ADV挽救治疗前4例患者血清HBV DNA为4.28(2.93~7.45)log10IU/ml,ALT为42.5(34~51)U/L。4例患者接受了40.5(14~63)个月的ETV+ADV联合治疗后均应答不佳,其中2例患者仍可检出ETV耐药突变株。4例患者换用TDF±ETV继续挽救治疗32.5(23~40)个月,分别在3、28、3、17个月血清HBV DNA达到<40IU/ml的临床检测下限,ALT均恢复正常,但本课题组建立的超灵敏方法在3例患者样本中克隆到了HBV基因序列,其中2例以野生株为主,1例以ET V耐药株为主。结论对ET V耐药患者加用ETV+ADV可出现应答不佳,换用TDF±ETV挽救治疗疗效良好,但即使治疗后临床检测不到血清HBV DNA,仍可有低水平HBV复制,需要长期抗病毒治疗。

Objective To analyze the clinical efficacy and virological evolution in nucleos（t）ide analogues-refractory patients with entecavir（ET V）-resistant mutation who had a suboptimal response to ET V＋adefovir（ADV） combined rescue therapy and received subsequent tenofovir（TDF）±ETV rescue therapy. Methods The HBV reverse transcriptase（RT） gene was amplified from the serum of 4 ETV-resistant patients. Drug-resistant mutation was determined by direct sequencing and verified by clonal sequencing. The clinical efficacy and virological evolution of the patients who received the sequential rescue therapies were retrospectively analyzed. Results HBV DNA level was 4.28（2.93-7.45）log10 IU/ml and ALT level was 42.5（34-51）U/L prior to ETV＋ADV rescue therapy. All 4 patients had suboptimal response and 2 patients kept detectable ETV-resistant mutants after receiving 40.5（14-63） months of ETV＋ADV therapy. The 4 patients were subsequently switched to TDF±ETV treatment for 32.5（23-40） months and achieved clinically undetectable serum HBV DNA level（40 IU/ml） after 3, 28, 3, and 17 months respectively; while using more sensitive in-house clonal sequencing identified viral sequences in 3 patients＇ samples, including two with dominant wild-type strains（P1 and P3）, and one with ETV-resistant mutant（P2）. All patients achieved ALT normalization. Conclusions ETV-resistant patients may have inadequate response to ETV＋ADV rescue therapy. Switching to TDF±ETV therapy has an optimal therapeutic efficacy. However, low-level viral replication may still persist and long-term antiviral therapy is needed.