Abstract: Objective The aim of this study was to investigate the efficacy of tenofovir rescue therapy for patients with chronic hepatitis B (CHB) and rtM204 mutation.Methods 94 patients with CHB who had failed to adefovir or lamivudine therapy with confirmed rtM204 mutation were enrolled in our hospital between April 2016 and February 2019, and were randomly divided into two groups, receiving tenofovir in 47 cases, or entecavir in 47 cases for rescue therapy for 18 months. Serum HBV DNA, HBsAg and HBeAg, and creatinine clearance (Crcl) were obtained. The peripheral blood CD3⁺ and CD4⁺ cell percentages were detected by FCM.Results At the end of 6, 12 and 18 month observation, serum HBV DNA loss in tenofovir-treated patients were 66.0%, 76.6% and 93.6%, all significantly higher than 38.3%, 55.3% and 78.7%(all P＜0.05) in entecavir-treated patients; at the end of 18 month, serum HBeAg negative rate in tenofovir-treated patients was 12.8%, much higher than that in entecavir-treated patients (0.0%, P＜0.05); at the end of 6 month and 18 month, serum AST levels in tenofovir-treated patients were (50.2±8.1)U/L and (31.7±6.9)U/L, significantly lower than [(57.7±8.3)U/L and (38.4±7.1)U/L, P＜0.05] in entecavir-treated patients; at 6 month, 12 month and 18 month observation, the percentages of CD3⁺ cells in tenofovir-treated patients were (31.6±5.2)%, (38.1±5.7)% and (40.2±6.2)%, not significantly different compared to [(32.1±5.5)%, (37.6±5.8)% and (39.1±5.9)%, P＞0.05], that of CD4⁺ cells were(28.6±3.9)%, (31.2±5.3)% and (36.1±5.7)%, not significantly different compared to [(29.3±3.7)%, (32.4±5.9)% and (34.5±5.3)%, P＞0.05], and Crcl were (103.4±39.3)mL/min, (101.2±30.2)mL/min and (97.6±23.8)mL/min, not significantly different compared to [(106.7±40.1)mL/min, (103.5±31.6)mL/min and (99.5±25.4)mL/min, respectively, P＞0.05] in entecavir-treated patients.Conclusion The administration of tenofovir for rescue therapy of patients with rtM204 mutation thanks to failed antiviral treatment might have a better efficacy, superior to entecavir, and warrants further and long-term investigation.

Key words: Hepatitis B, Tenofovir, rtM204 mutation, Rescue therapy