Tenofovir versus tenofovir plus entecavir for chronic hepatitis B with lamivudine resistance and entecavir resistance

We compared the viral suppressive efficacy of tenofovir disoproxil fumarate (TDF) mono‐rescue therapy (TDF group) and TDF plus entecavir (ETV) combination‐rescue therapy (TDF + ETV group) in chronic hepatitis B (CHB) patients with lamivudine resistance and entecavir resistance. One hundred and thirty‐three CHB patients with lamivudine and entecavir resistance were investigated. Ninety‐six patients were treated with TDF and 37 with TDF + ETV for at least 6 months. We compared the virologic response rate (HBV DNA level <20 IU/mL) between the two groups and identified the predictive factors of treatment outcome. There were no significant differences between the two groups in demographic characteristics. Up to 24 months [median: 18 (range 6‐24) months], 85.4% and 89.2% of the TDF group and TDF + ETV group, respectively, achieved a virologic response (P=.068). Only the HBV DNA level at baseline was significantly associated with a virologic response in the multivariate analysis. In a subanalysis of patients with HBV DNA levels ≥4 log (IU/mL) at baseline, a higher proportion of patients in the TDF + ETV group than the TDF group achieved a virologic response (92.9% vs 68.3%; P<.001), while 90% of patients with HBV DNA (IU/mL) levels <4 log in all both TDF and TDF + ETV groups achieved a virologic response. TDF mono‐rescue therapy is a reasonable option in patients with lamivudine resistance and entecavir resistance. However, the combination strategy should be considered in patients with high baseline HBV DNA levels.     

First-line treatment of chronic hepatitis B with entecavir or tenofovir in 'real-life' settings: from clinical trials to clinical practice

Entecavir (ETV) and tenofovir disoproxil fumarate (TDF) are potent nucleos(t)ide analogues (NUCs) recommended as first-line monotherapies for chronic hepatitis B. In Phase III trials, ETV and TDF demonstrated superior efficacy, and comparable safety compared with other NUCs. In long-term clinical studies, both drugs achieved virologic response rates of around 95%, with very low rates of resistance development and good safety profiles. Clinical trials are conducted under standardized conditions with strict enrolment criteria that limit the heterogeneity of study populations. 'Real-life' populations tend to be composed of a wider range of patients, often older and with different morbidities, comorbidities that may impact treatment efficacy and co-factors, such as smoking and alcohol intake, which can have a direct impact on disease progression. Real-life studies provide better representations of everyday clinical practice and are important to confirm the results reported in clinical studies and to identify rare or late-emerging adverse events. In five 'real-life' studies of ETV in more than 1000 patients, up to 4 years of treatment resulted in virologic responses in 76-96% of patients. Two real-life studies of TDF reported response rates of 71-92% after up to 21 months of treatment. Low incidences of drug resistance and favourable tolerabilities were reported for both drugs, thus confirming the results from registration trials.     

替诺福韦酯对阿德福韦酯应答不佳患者的挽救治疗研究进展

阿德福韦酯(adefovir dipivoxil,ADV)作为常用抗HBV治疗药物,与拉米夫定(lamivudine,LAM)、替比夫定和恩替卡韦无交叉耐药,且价格相对低廉,长期以来用于初治患者和LAM耐药患者的挽救治疗。然而由于ADV耐药基因屏障较低且临床用药剂量较低,临床长期应用累积了较多ADV应答不佳患者。替诺福韦酯(tenofovir disoproxil fumarate,TDF)作为ADV应答不佳患者的挽救治疗方案之一,对ADV初治应答不佳患者和LAM耐药的ADV应答不佳患者的临床疗效略有差异。然而多项体外研究显示TDF对ADV耐药病毒株抑制作用减弱。ADV应答不佳的患者换用TDF是否会引起或加重肾损害值得临床关注。本文就TDF对ADV应答不佳患者挽救治疗的国内外研究进展作综述,为提高耐药HBV感染防治的管理提供帮助。     

Optimal drug administration manner would rescue partial virological response in chronic hepatitis B patients with entecavir or tenofovir treatment

Not all treatment‐naïve patients receiving entecavir (ETV) or tenofovir disoproxil fumarate (TDF) therapy can achieve complete virological response, and many factors may be related with the outcome of partial virological response. This study aimed to determine whether the manner of drug administration affects the antiviral efficacy of ETV/TDF monotherapy. All eligible patients were divided into complete or partial response cohorts based on their virological response following 24‐week therapy. Factors related with partial response were evaluated. Patients with partial response were further grouped depending on whether they later adjusted the manner of drug administration, and the antiviral efficacy was compared between the two groups during prolonged treatment. A total of 518 patients were enrolled. Suboptimal drug administration (OR 77.511, P = .000), positive‐HBeAg (OR 3.191, P = .000) and ETV treatment (OR 2.537, P = .001) were identified as independent risk factors for partial response. Among patients with partial response, 213 were in the adjusted group and 76 were in the unadjusted group. The percentages of patients with undetectable serum HBV DNA (78.9% vs 31.6%, P < .001) and with normal alanine aminotransferase (ALT) (88.7% vs 68.4%, P < .001) were both higher in the adjusted group than that in unadjusted group following a further 6‐month therapy. In conclusion, the manner of drug administration is an important factor influencing the efficacy of ETV/TDF therapy, and optimal drug administration manner can help to increase antiviral efficacy and rescue patients with partial response.     

Validation of risk prediction scores for hepatocellular carcinoma in patients with chronic hepatitis B treated with entecavir or tenofovir

Several prediction scores for the early detection of hepatocellular carcinoma (HCC) are available. We validated the predictive accuracy of age, albumin, sex, liver cirrhosis (AASL), RESCUE‐B, PAGE‐B and modified PAGE‐B (mPAGE‐B) scores in chronic hepatitis B (CHB) patients treated with entecavir (ETV) or tenofovir disoproxil fumarate (TDF). Between 2007 and 2014, 3171 patients were recruited (1645, ETV; 1517, TDF). The predictive accuracy of each prediction score was assessed. The mean age of the study population (1977 men; 1194 women) was 48.8 years. Liver cirrhosis was present in 1040 (32.8%) patients. During follow‐up (median, 58.2 months), 280 (8.8%) patients developed HCC; these patients were significantly older; more likely to be male; had significantly higher proportions of liver cirrhosis, hypertension and diabetes; and had significantly higher values for the four risk scores than those who did not develop HCC (all P < .05). Older age (hazard ratio [HR] = 1.048), male sex (HR = 2.142), liver cirrhosis (HR = 3.144) and prolonged prothrombin time (HR = 2.589) were independently associated with an increased risk of HCC (all P < .05), whereas a higher platelet count (HR = 0.996) was independently associated with a decreased risk of HCC (P < .05). The predictive accuracy of AASL score was the highest for 3‐ and 5‐year HCC predictions (areas under the curve [AUCs] = 0.818 and 0.816, respectively), followed by RESCUE‐B, PAGE‐B and mPAGE‐B scores (AUC = 0.780‐0.815 and 0.769‐0.814, respectively). In conclusion, four HCC prediction scores were assessed in Korean CHB patients treated with ETV or TDF. The AASL score showed the highest predictive accuracy.     

Tenofovir‐based alternate therapies for chronic hepatitis B patients with partial virological response to entecavir

Entecavir (ETV) is a first‐line antiviral therapy for treating chronic hepatitis B (CHB); however, some patients have suboptimal response to ETV. Currently, there are limited data on how to approach these patients. Therefore, our aim was to compare the effectiveness of two alternate therapies – tenofovir (TDF) monotherapy and combination therapy of ETV+TDF – in CHB patients with ETV partial virological response. We conducted a retrospective study of 68 patients who had partial virological response to ETV, defined as having detectable HBV DNA following at least 12 months of ETV, and were switched to TDF monotherapy (n = 25) or ETV+TDF (n = 43). Patients were seen in seven US liver/community‐based clinics and started on ETV between 2005 and 2009. The majority of patients were male; the vast majority were Asian and had positive hepatitis B e antigen (HBeAg). Patients in both groups had similar pretreatment characteristics. Complete viral suppression (CVS) rates with TDF monotherapy and ETV+TDF were similar after 6 months (71% vs 83%, P = 0.23) and 12 months (86% vs 84%, P = 0.85), and there was no statistically significant difference in CVS rates even when only patients with higher HBV DNA levels at switch (>1000 IU/mL) were evaluated. Multivariate analysis indicated that ETV+TDF was not an independent predictor of CVS compared to TDF monotherapy (OR = 1.19, P = 0.63). In conclusion, TDF monotherapy and ETV+TDF are comparable in achieving CVS in CHB patients with partial virological response to ETV. Long‐term alternate therapy with one pill (TDF monotherapy) vs two pills (ETV+TDF) could lead to lower nonadherence rates and better treatment outcomes.     

Renal safety of tenofovir disoproxil fumarate and entecavir with hepatitis B immunoglobulin in liver transplant patients

Potent nucleos(t)ide analogues and hepatitis B immunoglobulin combinations are recommended after liver transplantation to prevent the recurrence of hepatitis B virus (HBV). Despite its proven efficacy, the renal safety of tenofovir disoproxil fumarate (TDF) has not been well established in liver transplant recipients. We aimed to assess the impacts of TDF and entecavir (ETV) on tubular and glomerular functions. We analysed 206 liver transplant patients treated with TDF (n = 102) or ETV (n = 104) plus hepatitis B immunoglobulin. Serum creatinine, phosphate and uric acid levels were measured. Proximal tubular dysfunction was defined as the presence of hypophosphatemia (<2 mg/dL) and hypouricemia (<2 mg/dL). Glomerular dysfunction was defined as an estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m² accompanied by a ≥25% eGFR decline from baseline. During a median follow‐up of 42.5 months, 48 patients developed proximal tubular dysfunction (30.4% and 16.3% in the TDF and ETV groups; P = .017). Serum levels of phosphate and uric acid were significantly lower in the TDF group post‐LT. TDF (OR, 2.34; 95% CI, 1.16‐4.69; P = .017) and low body mass index (OR, 2.11; 95% CI, 1.06‐4.21; P = .034) were independent risk factors for proximal tubular dysfunction. The prevalence of glomerular dysfunction was not significantly different between the two groups (TDF 51.0% and ETV 54.8%; P = .582). TDF significantly increased the risk of proximal tubular dysfunction. Although the effect of TDF on glomerular function was comparable to that of ETV, glomerular dysfunction was common after liver transplant.     

Long-term efficacy of entecavir in adefovir-refractory chronic hepatitis B patients with prior lamivudine resistance

This study aimed to evaluate the long-term efficacy of entecavir (ETV) in adefovir (ADV)-refractory chronic hepatitis B (CHB) patients with prior lamivudine (LMV) resistance. A total of 55 ADV-refractory CHB patients with prior LMV resistance, who received rescue therapy with ETV 1 mg daily for at least 12 months, were consecutively enrolled and analysed. Forty-four patients were men, and their median age was 47 (25-69). Ten patients had liver cirrhosis and 46 patients were positive for hepatitis B e antigen (HBeAg). Median hepatitis B virus DNA levels were 6.6 (4.3-8.0) log(10) copies/mL, and the median duration of ETV therapy was 24 (12-47) months. Cumulative virologic response rates at 6, 12, 24 and 36 months were 18%, 29%, 58% and 75%, respectively. HBeAg loss occurred in 10 (21.7%) of 46 HBeAg-positive patients. In multivariate analysis, only initial virologic response at 3 months remained as an independent predictor for virologic response (RR 3.143; 95% CI 1.387-7.120; P = 0.006). The patients with a virological response at 3 months had not only a significantly higher probability of achieving a virologic response (P < 0.001) but also lower probability of experiencing a virologic breakthrough (P = 0.043) than the patients without an early response. Viral breakthrough was observed in 29 patients during the follow-up period. Cumulative breakthrough rates at 6, 12, 24 and 36 months were 0%, 15%, 45% and 73%, respectively. ETV monotherapy may be considerably efficacious in cases with an initial virological response but its efficacy is attenuated by frequent emergence of ETV resistance in ADV-refractory CHB patients with prior LMV resistance.     

Comparison of 48‐week efficacy of tenofovir vs entecavir for patients with chronic hepatitis B: A network meta‐analysis

Both tenofovir disoproxil fumarate (TDF) and entecavir (ETV) are accepted as first‐line treatments for chronic hepatitis B (CHB). However, there are few randomized studies comparing their efficacy. The primary aim of this study was to compare the efficacy of TDF and ETV using a network meta‐analysis of randomized trials. The secondary aim was to additionally include propensity‐matched cohort studies in a conventional meta‐analysis. We systematically searched PubMed, EMBASE, Cochrane Library and Web of Science for published English‐language randomized and propensity‐matched studies between 1/1/2000 and 4/2/2020. Outcomes included undetectable HBV DNA, ALT normalization and HBeAg seroconversion at 48 weeks. We excluded patients who had co‐infection or significant prior treatment with antivirals. 13 517 participants from 16 studies (11 RCTs, n = 2675; five propensity‐matched cohort studies, n = 10 842) were included. Virological response at 48 weeks was higher in patients receiving TDF compared to ETV using both the network meta‐analytic approach (OR 1.69, P < .001) and the conventional meta‐analysis including propensity‐matched cohort studies (OR 1.40, P < .001). On subgroup analysis, this difference was only significant in HBeAg‐positive patients (OR 1.81, P = .037). There was limited evidence to suggest a higher rate of ALT normalization with ETV (OR 0.74, P = .07). There was no difference in rates of HBeAg seroconversion between the two antivirals. TDF is more likely than ETV to induce virological response at 48 weeks in treatment‐naïve CHB patients. Future studies should focus on elucidating associations between early and sustained virological response with adverse patient outcomes including development of HCC or cirrhosis.     

恩替卡韦治疗慢性乙型肝炎的疗效观察

目的评价恩替卡韦治疗慢性乙型肝炎(CHB)患者96周的疗效。方法收集2011年7月-2014年7月在江苏省泰兴市人民医院门诊和住院的62例CHB患者,给予恩替卡韦0.5 mg/d抗病毒治疗96周。所有病例分为两组,HBe Ag阳性组患者43例,HBe Ag阴性组患者19例。其中HBV DNA106拷贝/ml患者38例,HBV DNA106拷贝/ml患者24例。比较两组治疗24、48及96周的疗效。计数资料组间比较采用χ2检验。结果在治疗24、48、96周时,HBe Ag阳性组患者HBV DNA阴转率分别为34.88%、65.12%、74.42%,明显低于HBe Ag阴性组的78.95%、89.47%、100%,差异均有统计学意义(P值分别为0.003、0.047、0.038)。两组患者的ALT复常率差异均无统计学意义(P值分别为0.102、0.779、0.638)。在38例HBV DNA载量106拷贝/ml和24例HBV DNA载量106拷贝/ml的两组中,治疗24、48、96周时,两组患者HBV DNA阴转率差异均有统计学意义(34.21%vs70.83%、57.89%vs 95.83%、76.32%vs 95.83%,P值分别为0.005、0.001、0.002);两组患者ALT复常率差异均无统计学意义(P值分别为0.940、0.150、0.280)。结论恩替卡韦治疗CHB有很好的抗病毒活性,在抑制病毒复制的同时能改善肝功能。     

Failure of adefovir 20 mg to improve suboptimal response in lamivudine‐resistant hepatitis B patients treated with adefovir 10 mg and lamivudine

Summary. Nine patients with lamivudine‐resistant chronic hepatitis B infection who had been treated with adefovir 10 mg/day and had had a suboptimal response but did not have genotypic resistance to adefovir were treated with high‐dose adefovir (20 mg/day). The response to the increased dose of adefovir was compared with the response in 15 patients with a suboptimal response who did not receive an increase in the dose of adefovir. The increase in the dose of adefovir did not lead to a significant reduction in hepatitis B DNA when compared with patients maintained on the standard dose. These data suggest that increasing the dose of adefovir in patients with a suboptimal response does not lead to an improved response.     

Prevention of lamivudine‐resistant hepatitis B recurrence after liver transplantation with entecavir plus tenofovir combination therapy and perioperative hepatitis B immunoglobulin only

T. Karlas, J. Hartmann, A. Weimann, M. Maier, M. Bartels, S. Jonas, J. Mössner, T. Berg, H.L. Tillmann, J. Wiegand. Prevention of lamivudine‐resistant hepatitis B recurrence after liver transplantation with entecavir plus tenofovir combination therapy and perioperative hepatitis B immunoglobulin only.
Transpl Infect Dis 2011: 13: 299–302. All rights reserved Abstract: Combination therapy with antivirals plus hepatitis B immunoglobulin (HBIg) has become the standard treatment for prevention of post‐liver transplant hepatitis B virus (HBV) recurrence. However, HBIg therapy is inconvenient and expensive. Alternative therapeutic approaches with modern nucleos(t)ide analogues are limited so far. The present case report describes prevention of HBV recurrence with entecavir and tenofovir. A 48‐year‐old male patient with hepatitis B‐induced decompensated liver cirrhosis initially improved on lamivudine (LAM) until LAM resistance (rtL180M and rtM204V) emerged followed by renewed decompensation. Therefore, tenofovir was added to LAM leading to undetectable HBV DNA (<200 copies/mL). Six months later, low‐level viremia (479 copies/mL) was detected. Treatment was escalated to tenofovir plus entecavir. HBV DNA became negative again, and the patient underwent orthotopic liver transplantation. HBIg was administered during transplantation (10,000 IU) and on the second and third postoperative days (total dose 26,000 IU). Subsequently, the anti‐hepatitis B surface (HBs) titer rose to 1477 IU/L at day 4 post transplantation. Although HBIg should have been continued, the patient remained on combination therapy with tenofovir plus entecavir only. The anti‐HBs titer decreased and became negative 4 months later. However, under continued combination therapy with oral antivirals, HBV DNA and hepatitis B surface antigen remained negative during the entire follow‐up of 21 months after liver transplantation. Combination therapy with entecavir plus tenofovir may prevent post‐liver transplant hepatitis B recurrence even without HBIg maintenance therapy. This case illustrates that combination oral antiviral therapy might substitute for HBIg as indefinite prophylactic regimen due to profound antiviral efficacy and low risk of viral resistance. Efficacy and safety must be further investigated in randomized controlled trials.