No detectable resistance to tenofovir disoproxil fumarate in HBeAg+ and HBeAg- patients with chronic hepatitis B after 8 years of treatment

Efficacy and Safety of Tenofovir Plus Entecavir Combination Therapy Versus Tenofovir Monotherapy in Chronic Hepatitis B Virus Patients With Resistance or Partial Response to Entecavir: A Systematic Review and Meta-analysis

Background and objectives

Chronic hepatitis B virus remains a significant cause of liver disease in the developing world, leading to sequelae such as hepatocellular carcinoma. While entecavir (ETV) serves as a first-line treatment, its growing resistance rates underscore the need to explore viable alternatives. Tenofovir disoproxil fumarate (TDF) monotherapy and entecavir plus tenofovir (TDF + ETV) combination therapy are both employed as treatments, but one's efficacy over another is in question. This meta-analysis aims to investigate any primacy of either treatment.

Methods

We conducted a comprehensive literature search across PubMed/Medline, Embase, Cochrane Central, Web of Science, and China National Knowledge Infrastructure from inception till 7th October 2024. Studies comparing the safety and efficacy of TDF monotherapy versus TDF + ETV combination therapy in patients resistant to entecavir were considered. Data about the virologic response (VR), virologic breakthrough, HbeAg seroconversion, HbeAg/HbsAg seroclearance, and alanine aminotransferase normalization were extracted. Relative risks (RRs) and their corresponding 95% confidence intervals (CIs) were calculated, pooled, and analyzed in a random-effects model. P-value <0.05 was regarded as significant for all analyses.

Results

Nine studies, comprising 335 patients undergoing monotherapy and 352 patients undergoing combination therapy, satisfied the criteria. TDF + ETV combination therapy was found slightly advantageous to TDF monotherapy, stimulating a VR at 48 weeks (RR 1.081 95% CI: [1.001-1.167] P = 0.046, I2 = 0%), along with the HbeAg seroconversion rate (RR 1.711 95% CI: [1.005-2.913] P = 0.048, I2 = 0%). There were no significant adverse events in individual studies to warrant a meta-analysis.

Conclusions

TDF + ETV shows slightly better efficacy to TDF monotherapy over a 48-week treatment regimen, with minimal safety concerns. However, further high-quality studies like randomized controlled trials are needed to further solidify conclusions, with this meta-analysis only achieving borderline significances.

Registration

This review is registered on the PROSPERO database (ID: CRD42024581443).

Tenofovir-associated Fanconi syndrome in liver transplant recipients with hepatitis B: A retrospective case series

Tenofovir-associated Fanconi syndrome (TAFS) is a proximal renal tubule disorder rarely reported in patients after liver transplantation (LT) for hepatitis B (HBV). In a retrospective review of 79 HBV-LT recipients, 8/66 (12.1%) on tenofovir post-LT developed TAFS. Primary laboratory findings were hypophosphatemia (100%) and proteinuria (87.5%). No patients required renal replacement therapy or died from TAFS. The majority (85.7%) of surviving patients achieved tubular recovery after stopping tenofovir (mean: 13 weeks). In conclusion, TAFS is likely underdiagnosed in LT recipients. Regular screening for hypophosphatemia, proteinuria, and glucosuria is recommended for HBV-LT recipients on tenofovir, as most responded well to discontinuation.

Virological Response to Lamivudine and Tenofovir Treatment in a Mono-infected Chronic Hepatitis B Patient with Potential Tenofovir Resistance: A Case Report

Few cases of tenofovir resistance have been reported, and the appropriate treatment for such cases remains unclear. We aimed to share a case of a chronic hepatitis B mono-infected patient with potential tenofovir resistance who required combined lamivudine and tenofovir therapy to achieve adequate viral suppression. The patient's viral load (plasma) was monitored using the cobas® hepatitis B virus Test on the cobas® 6800 system. Hepatitis B antiviral drug resistance (AVDR) mutations were assessed by amplicon-based sequencing. Plasma was extracted using the MagNa Pure 24 system, and polymerase chain reaction targeting the polymerase gene (860bp) was performed. Sequencing was conducted on GridION R10.4.1 flow cells, and the resulting FASTQ files were analyzed using DeepChek®-HBV Software. We describe a female patient in her 60s with chronic hepatitis B who was e-antigen positive. She met treatment criteria in May 2020, when her alanine transaminase levels were 1.5 times above the upper limit of normal. She was initially started on entecavir but had to switch to tenofovir alafenamide in June 2020 due to a rash. Despite three years of tenofovir therapy, her viral load remained unsuppressed. AVDR testing identified two suspected tenofovir resistance mutations (V191I and A317S). Since no mutations associated with lamivudine resistance were detected, the patient was treated with a combination of lamivudine and tenofovir, achieving viral suppression after four months. Although rare, tenofovir resistance should be considered in patients with persistent viremia despite long-term therapy. AVDR sequencing facilitated the detection of potential tenofovir resistance and guided treatment decisions, leading to successful viral suppression in this case.

Efficacy and safety of tenofovir and entecavir in patients with chronic hepatitis B-related cirrhosis: a systematic review and meta-analysis

Objectives

To systematically evaluate the efficacy and safety of tenofovir and entecavir in chronic hepatitis B-related cirrhosis.

Methods

A comprehensive search was conducted in databases including PubMed, Web of Science, Embase and Cochrane Library from the inception until June 2024. Studies on the use of tenofovir and entecavir for chronic hepatitis B-related cirrhosis were collected.

Results

A total of 14 studies involving 14,208 patients were included. The meta-analysis revealed that tenofovir significantly reduced the cumulative incidence of hepatocellular carcinoma and cumulative mortality compared to entecavir in East Asian popupation, while in non East Asian populations, the two groups are roughly equivalent. After 48 weeks, the hepatitis B virus-deoxyribonucleic acid clearance rate in the tenofovir group were comparable to the entecavir group. Both tenofovir and entecavir showed similar effect in reducing the incidence of hepatic encephalopathy. Compared with the entecavir group, patients in the tenofovir group, including tenofovir disoproxil fumarate and tenofovir alafenamide fumarate showed a significant increase in estimated glomerular filtration rate after 48 weeks of treatment.

Conclusion

Compared to entecavir, tenofovir significantly reduced the cumulative incidence of hepatocellular carcinoma and cumulative mortality in chronic hepatitis B-related cirrhosis in East Asian population. However, both drugs were comparable in terms of hepatitis B virus-deoxyribonucleic acid clearance and hepatic encephalopathy. Tenofovir did not significantly cause renal dysfunction, but instead improved estimated glomerular filtration rate levels compared with entecavir. Randomized controlled trials with larger sample size are still needed for validation.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42024588432.

Overview of chronic hepatitis B management

ABSTRACT

Chronic hepatitis B remains a substantial global health challenge, impacting approximately 254 million people worldwide. A cure for this condition is yet to be discovered. Early identification and effective treatments coupled with vigilant monitoring can help alleviate associated morbidity and mortality due to potential complications such as liver cirrhosis and hepatocellular carcinoma.

Current trends and advances in antiviral therapy for chronic hepatitis B

ABSTRACT

Chronic hepatitis B virus (HBV) infection is a global public health concern. Existing antiviral drugs, including nucleos(t)ide analogs and interferon-α, can suppress HBV replication and improve the prognosis. However, the persistence of covalently closed circular DNA (cccDNA), the integration of HBV-DNA into the host genome, and compromised immune responses impede the successful treatment of hepatitis B. While achieving a functional cure of HBV remains elusive with the current treatment methods, this is the goal of new therapeutic approaches. Therefore, developing novel antiviral drugs is necessary for achieving a functional or complete cure for chronic hepatitis B. In recent years, substantial progress has been made in drug discovery and development for HBV infection. Direct-acting antiviral agents such as entry inhibitors, capsid assembly modulators, subviral particle release inhibitors, cccDNA silencers, and RNA interference molecules have entered clinical trials. In addition, several immunomodulatory agents, including toll-like receptor agonists, therapeutic vaccines, checkpoint inhibitors, and monoclonal antibodies, are also making their way toward clinical use. In this review, we summarize the recent progress and limitations of chronic hepatitis B treatment and discuss perspectives on approaches to achieving functional cure. Although it will take some time for these new antiviral drugs to be widely used in clinical practice, combination therapy may become a preferable treatment option in the future.

Real-world safety and effectiveness of tenofovir alafenamide for 144 weeks in Japanese patients with chronic hepatitis B

Tenofovir alafenamide (TAF), a prodrug of tenofovir, delivers high levels of active drug to hepatocytes and is given in a lower dose than tenofovir disoproxil fumarate (TDF). TAF reduces viral replication in patients with chronic hepatitis B (CHB) similar to TDF and has shown a lower risk of the renal and bone toxicities associated with TDF use. This post-marketing surveillance study examined the safety and effectiveness of TAF in treatment-naïve and -experienced CHB patients who received TAF for 144 weeks at real-world clinical sites in Japan. Safety assessments included the incidence of adverse drug reactions (ADRs), renal and bone events, and changes in selected laboratory parameters. Effectiveness was based on the proportion of patients with HBV DNA levels below the lower limit of quantitation or <29 IU/mL. This analysis included 580 patients; 18.4% of whom were treatment-naïve. The cumulative incidence of ADRs was 0.21 per 100 person-months, and the incidence of serious ADRs was 0.01 (95% CI, 0.00-0.04) per 100 person-months. There were no ADRs of declines in estimated glomerular filtration rates, renal failure or proximal tubulopathy. The most common ADR was hypophosphataemia in seven (1.2%) patients. Two (0.4%) patients each had decreased blood phosphorus, bone mineral density decreased, dizziness and alopecia. Overall, the proportion of virologically suppressed patients increased from 68.8% at baseline to 97.5% at Week 144. These results confirm the real-world safety and effectiveness of TAF in Japanese patients with CHB and are consistent with the findings of other evaluations of the safety and efficacy of TAF in CHB.

Association of tenofovir diphosphate and lamivudine triphosphate concentrations with HIV and hepatitis B virus viral suppression

OBJECTIVE

Concentrations of tenofovir diphosphate (TFV-DP) and lamivudine triphosphate (3TC-TP) in cells are correlates of medication adherence and antiviral activity. However, studies have yet to characterize the simultaneous relationship between TFV-DP and 3TC-TP concentrations with HIV and hepatitis B virus (HBV) suppression.

METHODS

Individuals with HIV/HBV coinfection on tenofovir disoproxil fumarate (TDF)-containing antiretroviral therapy (ART) were enrolled. Peripheral blood mononuclear cells (PBMCs) and dried blood spots (DBS) samples were collected and steady-state TFV-DP and 3TC-TP concentrations quantified using validated methods. The relationship between patient factors, TFV-DP, and 3TC-TP concentrations in PBMCs and DBS with HBV and HIV viral suppression were examined.

RESULTS

Of 138 participants on TDF-containing ART for a median duration (range) of 6 (0.75-15) years, the median age was 43 years and 64% were women. Overall, 128 (92.8%) and 129 (93.5%) had suppressed HIV and HBV viral loads, respectively. Of the 128 participants with suppressed HIV, 122 (95.3%) had suppressed HBV. Self-reported ART adherence, recent change to dolutegravir-based ART, TFV-DP, and 3TC-TP concentrations in PBMCs and DBS were associated with HIV RNA suppression, while HBe antigen positivity, HIV suppression, and TFV-DP concentrations in DBS were associated with HBV DNA suppression (including six persons with HBV nonsuppression and HIV suppression).

CONCLUSION

Long-term TDF/3TC-conatining ART was highly efficacious in individuals with HIV/HBV coinfection. Higher TFV-DP concentrations were predictive of suppression for both viruses. Persistent HBV viremia on TDF/3TC-containg ART requires additional research, but may represent poor adherence and the need for adherence interventions or novel antivirals.

Guidelines for the Prevention and Treatment of Chronic Hepatitis B (version 2022)

To facilitate the achieving of the goal of "eliminating viral hepatitis as a major public health threat by 2030" set by the World Health Organization, the Chinese Society of Hepatology together with the Chinese Society of Infectious Diseases (both are branches of the Chinese Medical Association) organized a panel of experts and updated the guidelines for prevention and treatment of chronic hepatitis B in China (version 2022). With the support of available evidence, this revision of the guidelines focuses on active prevention, large scale testing, and expansion of therapeutic indication of chronic hepatitis B with the aim of reducing the hepatitis B related disease burden.

A new approach to prevent, diagnose, and treat hepatitis B in Africa

There are 82 million people living with hepatitis B (PLWHB) in the World Health Organization Africa region, where it is the main cause of liver disease. Effective vaccines have been available for over 40 years, yet there are 990,000 new infections annually, due to limited implementation of hepatitis B birth dose vaccination and antenatal tenofovir prophylaxis for highly viraemic women, which could eliminate mother-to-child transmission. Despite effective and cheap antiviral treatment which can suppress hepatitis B virus replication and reduce the risk of hepatocellular carcinoma (HCC), < 2% of PLWHB are diagnosed, and only 0.1% are treated. As a result, PLWHB are frequently diagnosed only when they have already developed decompensated cirrhosis and late-stage HCC, and consequently 80,000 hepatitis B-associated deaths occur each year. Major barriers include complex treatment guidelines which were derived from high-income settings, lack of affordable diagnostics, lack or insufficient domestic funding for hepatitis care, and limited healthcare infrastructure. Current treatment criteria may overlook patients at risk of cirrhosis and HCC. Therefore, expanded and simplified treatment criteria are needed. We advocate for decentralized community treatment programmes, adapted for low-resource and rural settings with limited laboratory infrastructure. We propose a strategy of treat-all except patients fulfilling criteria that suggest low risk of disease progression. Expanded treatment represents a financial challenge requiring concerted action from policy makers, industry, and international donor agencies. It is crucial to accelerate hepatitis B elimination plans, integrate hepatitis B care into existing healthcare programmes, and prioritize longitudinal and implementation research to improve care for PLWHB.

Are the New Nucleos(t)ide Analogs Better than the Old Nucleos(t)ide Analogs?

In treatment-naïve patients with chronic hepatitis B virus (HBV) infection, entecavir (ETV), tenofovir disoproxil fumarate (TDF), and tenofovir alafenamide have a minimal or no risk of drug-resistance. These 3 nucleos(t)ide analog agents are highly potent inducing high rate of virologic response (reducing serum HBV DNA to levels undetectable by polymerase chain reaction assays) in most treatment-naïve patients. Our randomized trials have demonstrated that monotherapy with TDF can provide a successful virological response in most of the heavily pretreated patients with multidrug resistance to ETV or adefovir.

Safety considerations for withdrawal of nucleos(t)ide analogues in patients with chronic hepatitis B: First, do no harm

Nucleos(t)ide analogues (NA) are widely used to treat hepatitis B virus (HBV) infection, but they cannot eradicate the virus and treatment duration can be lifelong if the endpoint is set at seroclearance of the hepatitis B surface antigen (HBsAg). As an alternative strategy, finite NA therapy without the prerequisite of HBsAg seroclearance has been proposed to allow treatment cessation in patients with sustained undetectable HBV viremia for two to three years. However, reactivation of viral replication almost always follows NA withdrawal. Whereas HBV reactivation might facilitate HBsAg seroclearance in some, it could lead to serious acute flare-ups in a certain proportion of patients. Occurrence and consequences of NA withdrawal flares are complicated with various factors involving the virus, host, and treatment. Accurate risk prediction for severe flares following NA cessation is essential to ensure patient safety. The risks of life-threatening flares in patients who discontinued NA according to the stopping rules of current guidelines or local reimbursement policies have recently been quantitatively estimated in large-scale studies, which also provided empirical evidence to help identify vulnerable patients at risk of devastating outcomes. Moreover, risk predictors were further explored and validated to hopefully aid in patient selection and management. In this narrative review with a focus on patient safety, we summarize and discuss current literature on the incidence of severe flares following NA cessation, risk stratification for candidate selection, rules of posttreatment monitoring, and indications for treatment resumption. We also share our thoughts on the limitations of existing knowledge and suggestions for future research.

Characterization of Hepatitis B Virus in Tenofovir-Treated and Untreated Chronically Infected Mothers and Their Immunoprophylaxis Failure Infants

BACKGROUND

Maternal tenofovir disoproxil fumarate (TDF) therapy during late pregnancy can reduce mother-to-infant transmission of hepatitis B virus (HBV). We investigated HBV mutations associated with maternal TDF therapy and their role in infant immunonophylaxis failure (IPF).

METHODS

Serum samples from untreated (n = 89) and TDF-treated (n = 68), highly viremic, chronically infected mothers and their infants were analyzed for HBV DNA by nested polymerase chain reaction (PCR) and direct sequencing.

RESULTS

At delivery, compared with untreated mothers, TDF-treated mothers had a lower HBV DNA titer and a higher frequency of basal core promoter (BCP) gene mutations, but they had similar frequencies in pre-S/S and pre-core/core mutations. The 14 mothers harboring surface "a" determinant mutants did not transmit the mutants to their immunized infants. Such mutants were found in 3 of 13 IPF infants; the 13 mothers had wild-type hepatitis B surface antigen (HBsAg). In univariable analysis, maternal HBV DNA titer (odds ratio [OR]: 1.54; 95% confidence intervals [CI]: 1.02-2.33; P = .039), genotype C (OR: 4.18; 95% CI: 1.28-13.62; P = .018) and pre-S1 wild-type sequence (OR: 6.33; 95% CI: 1.85-21.68; P = .003) at delivery were associated with infant IPF. Multivariable analyses showed that maternal genotype C (OR: 3.71; 95% CI: 1.11-12.36; P = .033) and pre-S1 wild-type (OR: 6.34; 95% CI: 1.79-22.44; P = .004) were associated with infant IPF independently of maternal viremia.

CONCLUSIONS

Along with high maternal HBV DNA titer at delivery, maternal genotype C and pre-S1 wild-type sequence were potential risk factors for infant IPF, although BCP mutations were not. The offspring of pregnant women harboring "a" determinant mutants as major strains seemed to be protected by immunoprophylaxis.

CLINICAL TRIALS REGISTRATION

NCT01312012.

Effective Analysis of Antiviral Treatment in Patients with HBeAg-Seropositive Chronic Hepatitis B with ALT < 2 Upper Limits of Normal: A Multi-center Retrospective Cohort Study

INTRODUCTION

Although the indications for antiviral therapy for patients with chronic hepatitis B have been gradually expanded in different guidelines, antiviral treatment efficacy remains unclear among HBeAg-seropositive patients with alanine aminotransferase (ALT) < 2 upper limits of normal (ULN). This study aimed to evaluate the efficacy of antiviral therapy for these patients.

METHODS

In total, 102 treatment-naive patients who were HBeAg seropositive with ALT < 2 ULN and had received nucleotide analogs were included, and their clinical data were retrospectively analyzed.

RESULTS

After 96-week treatment, 84.3% (n = 86), 26.5% (n = 27) and 20.6% (n = 21) patients achieved virological response, HBeAg seroclearance and HBeAg seroconversion, respectively. Logistic regression analysis revealed that baseline AST (odds ratio [OR] = 1.069, 95% confidence interval [CI] 1.014-1.127, p = 0.014), serum HBV DNA (OR = 0.540, 95% CI 0.309-0.946, p = 0.031) and quantitative HBsAg levels (OR = 0.147, 95% CI 0.036-0.597, p = 0.007) were independent factors for virological response. At baseline, HBsAg < 4.63 log₁₀ IU/ml was identified as a strong predictor for the 96-week virological response, with a concordance rate of 0.902. Moreover, the levels of liver stiffness values (8.30 ± 3.86 vs. 6.17 ± 1.91, p < 0.001) at week 96 had significantly declined compared to baseline.

CONCLUSION

Nucleotide analog treatment effectively suppressed HBV DNA in patients with HBeAg-seropositive chronic hepatitis B with ALT < 2 × ULN and greatly improved liver fibrosis. The study also found that HBsAg < 4.63 log₁₀ IU/ml was a strong predictor of the virological response.

Effectiveness of entecavir vs tenofovir disoproxil fumarate for functional cure of chronic hepatitis B in an international cohort

INTRODUCTION

Both entecavir (ETV) and tenofovir disoproxil fumarate (TDF) are first-line therapies for chronic hepatitis B (CHB), but their comparative effectiveness with regards to hepatitis B surface antigen (HBsAg) seroclearance remains unclear.

METHODS

This international multicenter cohort study enrolled 7697 treatment-naïve CHB patients (median age 50 years; male 66.75%) initiated on either ETV (n = 5430) or TDF (n = 2267) without baseline malignancy or immunosuppression from 23 centers across 10 countries or regions. Patients were observed for HBsAg seroclearance until death, loss to follow-up, or treatment discontinuation or switching. The incidences of HBsAg seroclearance were adjusted for competing mortality and compared between ETV and TDF cohorts with inverse probability of treatment weighting (IPTW) and also by multivariable regression analysis.

RESULTS

The study population was followed up for a median duration of 56.1 months with 36,929 11 person-years of observation. HBsAg seroclearance occurred in 70 ETV-treated and 21 TDF-treated patients, yielding 8-year cumulative incidence of 1.69% (95% confidence interval [CI] 1.32-2.17) for ETV and 1.34% (95% CI 0.85-2.10%), for TDF (p = 0.58). In the IPTW analysis with the two study cohorts more balanced in background covariates, the age-adjusted hazard ratio (HR) of TDF versus ETV for HBsAg seroclearance was 0.91 (95% CI 0.50-1.64; p = 0.75). Furthermore, there was no significant difference between the two medications in the multivariable competing risk regression model (adjusted sub-distributional HR 0.92 for TDF vs. ETV; 95% CI 0.56-1.53; p = 0.76).

CONCLUSIONS

ETV and TDF did not differ significantly in the incidence of HBsAg seroclearance, which rarely occurred with either regimen.

The Efficacy of Antiviral Treatment for Chronic Hepatitis B Patients with Normal ALT Levels: A Systematic Review and Meta-analysis

Context: When nucleos(t)ide analogues (NAs) were applied clinically to manage chronic hepatitis B virus infection, the prognosis of chronic hepatitis B (CHB) patients greatly improved. However, certain CHB patients with normal alanine aminotransferase (ALT) levels were not used to be considered as the population with the need for antiviral treatment. Objectives: This systematic review and meta-analysis collected and analyzed data from clinical trials to assess and compare the efficacy of antiviral treatment among patients with elevated and normal ALT levels. Methods: A systematic search was performed to gather studies published from 1990.01 to 2022.08 in PubMed and Web of Science databases. The quality of the literature was assessed, and 16 studies were included for further analysis. Basic information on included studies and study populations was collected. A meta-analysis was carried out to evaluate three major outcomes of viral response, hepatitis B envelope antigen (HBeAg) loss, and HBeAg seroconversion after NAs treatment based on data extracted from these studies. Odds ratios (ORs) with 95% confidence intervals (CIs) for all outcomes were calculated using fixed-effects models. Results: In the 16 relevant studies, 5,345 patients met the inclusion criteria, including 3,687 patients receiving NAs treatment. All patients were grouped into one with elevated ALT and another with normal ALT based on whether their pretreatment ALT levels > 1*upper limit of normal (ULN). For patients receiving lamivudine, the viral response showed no significant difference between the groups with elevated and normal ALT levels (pooled log OR: 0.51 [-0.23 - 1.26], P = 0.79); the pooled log OR for HBeAg loss was 1.19 (0.63 - 1.76, P = 0.03) and pooled log OR for HBeAg seroconversion was 2.19 (0.91 - 3.47, P = 0.40). For patients receiving first-line therapy with tenofovir disoproxil fumarate (TDF) and entecavir (ETV), the viral response showed no significant difference between the two groups: Pooled log OR (0.38 [-0.22 - 0.97], P = 0.10). The pooled log OR for HBeAg loss and HBeAg seroconversion was (-0.07 [-0.81 - 0.67], P = 0.68) and (0.40 [-0.84 - 1.63], P = 0.88), respectively. Conclusions: The efficacies of first-line therapy with TDF and ETV treatments were similar in groups with elevated and normal ALT levels for the outcomes of viral response and HBeAg loss. These findings may support further treatment of CHB patients with normal ALT levels.

Virological responses to tenofovir-alafenamide-containing antiretroviral therapy in people living with HIV co-infected with lamivudine-resistant or lamivudine-susceptible hepatitis B virus

BACKGROUND

Data on the effectiveness of tenofovir alafenamide (TAF) against lamivudine-resistant (LAM-R) hepatitis B virus (HBV) among patients co-infected with human immunodeficiency virus (HIV) and HBV are limited.

METHODS

Between April and December 2018, HIV-positive patients co-infected with LAM-R or lamivudine-susceptible (LAM-S) HBV who switched from tenofovir-disoproxil-fumarate-containing antiretroviral therapy (ART) to TAF-containing ART were followed for 96 weeks. Plasma HBV and HIV loads, HBV serological markers, and liver function before and after the switch were analysed.

RESULTS

In total, 182 patients co-infected with HIV and HBV were included in this study: 45 with LAM-R HBV and 137 with LAM-S HBV. At baseline, 28.9% and 7.4% of patients in the LAM-R and LAM-S groups, respectively, tested positive for hepatitis B virus envelope antigen (HBeAg) (P<0.001), and the respective percentages of patients who had achieved plasma HBV DNA <20 IU/mL were 95.5% and 97.1%. At weeks 48 and 96, 100% and 94.9% of patients in the LAM-R group, respectively, and 97.1% and 95.6% of patients in the LAM-S group, respectively, maintained plasma HBV DNA <20 IU/mL. Lamivudine resistance of HBV and baseline hepatitis B virus surface antigen (HBsAg) level were associated with HBsAg decrement at week 96 at a degree of 0.25 log₁₀ IU/mL [95% confidence interval (CI) 0.059-0.246] and 0.22 log₁₀ IU/mL (per 1-log₁₀IU/mL increase, 95% CI 0.018-0.101), respectively. At week 96, 2.2% (4/182) of patients had HBsAg loss; no patients in the LAM-R group and 25.0% (2/8) of patients in the LAM-S group had HBeAg seroconversion.

CONCLUSIONS

Switching to TAF-containing regimens maintained high rates of HBV viral suppression in patients co-infected with either LAM-R or LAM-S HBV. The decrease in HBsAg was minimal, and HBsAg seroconversion occurred infrequently.

Non-Inferior Efficacy of Tenofovir Disoproxil to Tenofovir Disoproxil Fumarate in Virologically Suppressed Chronic Hepatitis B Patients

Purpose

Tenofovir disoproxil (TD), modified from tenofovir disoproxil fumarate (TDF), was developed as a salt-free formulation, removing fumarate to improve the ease of oral intake by reducing the tablet's size. We evaluated the maintenance of antiviral effects and overall safety profile of TD 245 mg after switching from TDF 300 mg in patients with chronic hepatitis B (CHB).

Patients and Methods

CHB patients with HBV-DNA <69 IU/mL after ≥24 weeks of TDF therapy were enrolled. The primary efficacy endpoint was the HBV-DNA suppression rate (HBV-DNA <69 IU/mL) at week 48; We evaluated the non-inferiority (10% margin) of TD to TDF in terms of efficacy. Safety was assessed based on adverse events (AEs), laboratory tests, bone mineral density, and renal function abnormalities.

Results

Overall, 189 subjects were randomized in a 2:1 ratio, and 117 and 66 subjects in the TD and TDF groups, respectively, completed the study. In the per-protocol set, the HBV-DNA suppression rate at week 48 was 99.1% and 100% in the TD and TDF groups, respectively. The lower limit of the 97.5% one-sided confidence interval for the intergroup difference in HBV-DNA suppression rate was -2.8%, which was greater than the prespecified margin of non-inferiority. The changes in creatinine clearance from baseline to week 48 was significantly less in the TD group and in the TDF group; -0.8 ± 9.8 versus -2.4 ± 12.8 mL/min, respectively (P=0.017).

Conclusion

TD was non-inferior to TDF for maintaining viral suppression in CHB patients, showing the less decline of renal function.

Risks and benefits of oral HIV pre-exposure prophylaxis for people with chronic hepatitis B

Individuals with chronic hepatitis B virus (HBV) infection who are at substantial risk of HIV acquisition benefit from pre-exposure prophylaxis (PrEP) with tenofovir-based antiviral therapy. Considering that tenofovir potently inhibits HBV, providing PrEP to individuals with HBV effectively results in treatment of their HBV infection. However, some clinicians might be hesitant to initiate PrEP in people with chronic HBV due to unknown risks of HBV reactivation, hepatitis, and acute liver failure during periods of antiviral cessation. Unfortunately, these knowledge gaps affect scale up of PrEP among people with chronic HBV. Emerging data regarding the risks and benefits of antiviral cessation in people with chronic HBV suggest that PrEP can be safely initiated despite the risks of non-adherence or discontinuation. People with chronic HBV who stop PrEP should be closely monitored for HBV reactivation and hepatitis flares after antiviral cessation.

Tenofovir disoproxil fumarate therapy to prevent hepatitis B virus vertical transmission-A review of maternal and infant outcomes

Hepatitis B virus (HBV) is a global health problem. Vertical transmission of HBV from HBV surface antigen (HBsAg)-positive mothers to their infants is the most common cause of HBV infection worldwide. The use of passive-active immunoprophylaxis is >90% effective in reducing the risk of vertical transmission, but immunoprophylaxis failure can occur in infants born to mothers with high viraemia. Thus, it is recommended that pregnant women with HBV-DNA level >200 000 IU/ml receive nucleos(t)ide analogue (NA) treatment [i.e. tenofovir disoproxil fumarate (TDF), lamivudine or telbivudine] during third trimester to prevent infant immunoprophylaxis failure. TDF is recommended as the first-line therapy based on available data on efficacy, safety and resistance profile. However, maternal immunological reconstitution following parturition can increase immune-mediated flares to viral antigens that is potentially exacerbated following TDF withdrawal. In this article, we review available data on the efficacy and safety of TDF administration to prevent HBV mother-to-child transmission. We also discuss changes in maternal viral markers [i.e. HBV-DNA, HBV e antigen and HBsAg] and alanine aminotransferase during follow-up post-partum in mothers received NA to prevent HBV vertical transmission.

Tenofovir disoproxil fumarate for multiple nucleos(t)ide analogues treatment failure hepatitis B: Is monotherapy enough?

BACKGROUND AND AIM

Tenofovir disoproxil fumarate (TDF) is a first-line treatment for chronic hepatitis B virus (HBV) infection for its high potency and a low rate of drug resistance. This study investigated the efficacy and safety of TDF in Chinese patients with chronic hepatitis B (CHB) infection after treatment failure with multiple nucleos(t)ide analogues (NAs).

METHODS

Patients included were aged 18-65 years, with treatment failure with multiple NAs (serum HBV DNA > 200 IU/mL after more than two different NA treatments). The primary endpoint was proportion of patients with serum HBV DNA < 20 IU/mL at Week 144 of TDF monotherapy. Secondary endpoints and safety were also assessed.

RESULTS

Overall, 213 patients were enrolled. At Week 144, mean HBV DNA decreased significantly from baseline (4.4 vs 1.4 log₁₀ IU/mL), with 77.0% patients (95% confidence interval: 71.1, 82.9) achieving serum HBV DNA < 20 IU/mL. Three (1.4%) patients experienced virological breakthrough during TDF monotherapy, without hepatitis flare. At Week 144, 15.3% and 4.7% patients (hepatitis B e antigen [HBeAg]-positive at baseline) experienced HBeAg loss and HBeAg seroconversion, respectively; 68.3% patients achieved normalized alanine aminotransferase levels. Overall, 58.7% patients experienced more than one adverse event (AE). Most common AEs were upper respiratory tract infection and blood creatine phosphokinase increase; 8.5% patients experienced study drug-related AEs; 9.4% patients experienced serious AEs (none were TDF-related). Among renal safety parameters, overall trend of mean serum phosphorous level remained stable, while mean estimated glomerular filtration rate increased slightly.

CONCLUSIONS

Tenofovir disoproxil fumarate monotherapy is efficacious in CHB patients with multiple NAs treatment failure with no new safety findings.

Targeted long-read sequencing reveals clonally expanded HBV-associated chromosomal translocations in patients with chronic hepatitis B

Background & Aims

Methods

Results

Conclusions

Lay summary

•

Fresh frozen liver biopsies from patients with CHB were subjected to targeted long-read RNA and DNA sequencing.

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Inter-chromosomal translocations associated with HBV integration events detected in one-third of patients.

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Chromosomal translocations were unique to each biopsy sample, suggesting that each originated randomly.

•

A larger fraction of the HBV transcriptome originates from cccDNA in patients who are HBeAg-positive.

Tenofovir vs. entecavir on recurrence of hepatitis B virus-related hepatocellular carcinoma beyond Milan criteria after hepatectomy

BACKGROUND

Hepatectomy for hepatocellular carcinoma (HCC) beyond the Milan criteria is shown to be beneficial. However, a high rate of post-operative HCC recurrence hinders the long-term survival of the patients. This study aimed to investigate and compare the impacts of tenofovir (TDF) and entecavir (ETV) on the recurrence of hepatitis B viral (HBV)-related HCC beyond the Milan criteria.

METHODS

Data pertaining to 1532 patients who underwent hepatectomy and received antiviral therapy between January 2014 and January 2019 were collected from five centers. Recurrence-free survival (RFS) analysis was performed using the Kaplan-Meier method. Cox proportional hazards regression analysis was performed to determine prognostic factors for HCC recurrence.

RESULTS

The analysis incorporates 595 HBV-related HCC patients. The overall 5-year RFS was 21.3%. Among them, 533 and 62 patients received ETV and TDF treatment, respectively. The 1-, 3-, and 5-year RFS rates were 46.3%, 27.4%, and 19.6%, respectively, in the ETV group compared with 65.1%, 41.8%, and 37.2%, respectively, in the TDF group (P < 0.001). Multivariate analysis showed that TDF treatment (hazard ratio [HR]: 0.604, P = 0.005), cirrhosis (HR: 1.557, P = 0.004), tumor size (HR: 1.037, P = 0.008), microvascular invasion (MVI) (HR: 1.403, P = 0.002), portal vein tumor thrombus (PVTT) (HR: 1.358, P = 0.012), capsular invasion (HR: 1.228, P = 0.040), and creatinine levels (CREA) (HR: 0.993, P = 0.031) were statistically significant prognostic factors associated with RFS.

CONCLUSIONS

Patients with HCC beyond the Milan criteria exhibited a high rate of HCC recurrence after hepatectomy. Compared to the ETV therapy, TDF administration significantly lowered the risk of HCC recurrence.

Present and future management of viral hepatitis

Viral hepatitis can result in important morbidity and mortality, with its impact on health conditioned by the specific type of hepatitis, the geographical region of presentation and the development and access to new drugs, among other factors. Most acute presentation forms are self-limiting and may even go unnoticed, with just a small percentage of cases leading to acute liver failure that may necessitate transplantation or even cause the death of the patient. However, when they become chronic, as in the case of hepatitis B virus and C virus, unless they are diagnosed and treated adequately they may have severe consequences, like cirrhosis or hepatocarcinoma. Understanding of the mechanisms of transmission, the pathogenesis, the presence of vaccinations and the development over recent years of new highly-efficient, potent drugs have meant that we are now faced with a new scenario in the management of viral hepatitis, particularly hepatitis B virus and hepatitis C virus. The spectacular advances in hepatitis C virus treatment have led the World Health Organization to propose the objective of its eradication by 2030. The key aspect to achieving this goal is to ensure that these treatments reach all the more vulnerable population groups, in whom the different types of viral hepatitis have a high prevalence and constitute a niche that may perpetuate infection and hinder its eradication. Accordingly, micro-elimination programs assume special relevance at the present time.

Effectiveness of tenofovir alafenamide for chronic hepatitis B patients with a poor response to the previously used nucleos(t)ide analogs

BACKGROUND

Few studies have demonstrated the potency of tenofovir alafenamide (TAF) in patients with poor response to other nucleos(t)ide analogs (NAs).

METHODS

We conducted a retrospective study comprising consecutive 40 patients exhibiting a poor response to other NAs, who subsequently received TAF-containing regimens. The primary outcome was the prevalence of virological response (VR) at each time and maintained virological response (MVR) under TAF-containing regimens until week 96.

RESULTS

In the entire cohort, the prevalence of MVR was 71.1% (27/38). Further, poor tenofovir disoproxil fumarate (TDF) response was significantly associated with a lower prevalence of MVR (p = 0.014). In TDF-naïve patients, the prevalence of MVR was 92.3% (12/13) and 62.5% (5/8) in patients with lamivudine resistance (LAM-r) and entecavir resistance (ETV-r), respectively. Further, viral load and HBeAg status at baseline were associated with a lower prevalence of MVR (p = 0.013). Among the seven patients with prior TDF exposure, 2 patients achieved MVR. Among them, one patient with development of viral breakthrough during TDF/LAM achieved MVR after switching to TAF/ETV. In contrast, one of the five patients with non-MVR had three substitutions (rtS106C, rtD134N/S, and rtL269I) of quadruple mutations in addition to ETV-r. Other patients with rtA181T + rtN236T also could not achieve MVR.

CONCLUSION

TAF exhibited high antiviral potency in patients with LAM-r and ETV-r. However, TAF potency was associated with previous TDF response, viral load, and HBeAg status at baseline. Additionally, a quadruple mutation may impact tenofovir resistance; however, further studies are needed to verify this.

Guidelines for Prevention and Treatment of Chronic Hepatitis B

To achieve the goal of the World Health Organization to eliminate viral hepatitis as a major public health threat by 2030, the Chinese Society of Infectious Diseases and the Chinese Society of Hepatology convened an expert panel in 2019 to update the guidelines for the prevention and treatment of chronic hepatitis B (CHB). The current guidelines cover recent advances in basic, clinical, and preventive studies of CHB infection and consider the actual situation in China. These guidelines are intended to provide support for the prevention, diagnosis, and treatment of CHB.

Persistent HBV replication and serological response during up to 15 years of tenofovir-based antiretroviral therapy in HIV/HBV-coinfected patients: a multicentre prospective cohort study

OBJECTIVES

To determine the extent of hepatitis B virus (HBV) suppression and its association with seroclearance of hepatitis 'e' antigen (HBeAg) and hepatitis B surface antigen (HBsAg) in HIV/HBV-coinfected patients undergoing long-term tenofovir-based antiretroviral therapy (ART).

METHODS

We prospectively followed 165 HIV/HBV-coinfected patients undergoing tenofovir-based ART. Serum HBV-DNA viral loads and HBeAg and HBsAg status were obtained at tenofovir initiation and every 6-12 months. We calculated the proportion achieving virological response (VR, <60 IU/mL) during follow-up. We also calculated rates of HBeAg- and HBsAg-seroclearance, which were compared between those who achieved versus never achieved VR during follow-up using an Exact binomial test.

RESULTS

During a median 8.1 years (IQR = 4.0-13.2) of tenofovir treatment, 152 (92.1%) patients were able to achieve VR and 13 (7.9%) never achieved VR (median HBV-DNA at the end of follow-up = 608 IU/mL, range = 67-52 400 000). The prevalence of individuals with detectable HBV-DNA (≥60 IU/mL) decreased during tenofovir treatment: 15.1% (n = 14/93) at 5 years, 3.2% (n = 2/62) at 10 years and, 3.2% (n = 1/31) at 15 years. 44/96 HBeAg-positive patients (6.15/100 person-years) had HBeAg-seroclearance and 13/165 patients overall (0.87/100 person-years) had HBsAg-seroclearance. No difference in HBeAg-seroclearance was observed between those who achieved versus never achieved VR (7.4 versus 3.7/100 person-years, P = 0.33), while HBsAg-seroclearance was only observed in those with VR (1.0 versus 0/100 person-years, P = 0.49; respectively). Individuals with VR also had a higher frequency of undetectable HIV-RNA during treatment (P < 0.001).

CONCLUSIONS

During long-term tenofovir-based ART for HIV/HBV coinfection, persistent HBV viraemia is apparent, but becomes less frequent over time. HBsAg-seroclearance only occurred in those with full HBV and relatively high HIV suppression.

Differential Effectiveness of Tenofovir and Entecavir for Prophylaxis of Hepatocellular Carcinoma in Chronic Hepatitis B Patients Depending on Coexisting Cirrhosis and Prior Exposure to Antiviral Therapy: A Systematic Review and Meta-analysis

GOALS

This meta-analysis evaluated the comparative effectiveness of tenofovir disoproxil fumarate (TDF) versus entecavir (ETV) in reducing the risk of hepatocellular carcinoma (HCC).

BACKGROUND

It is unclear whether TDF or ETV is more effective in reducing the risk of HCC in chronic hepatitis B (CHB) patients with or without underlying cirrhosis.

METHODS

We searched the MEDLINE database through April 13, 2020, for studies involving CHB treated with TDF and/or ETV. Primary and secondary outcomes were the incidence of HCC and overall survival, respectively, calculated as risk ratios (RRs). Adjusted results were further evaluated by pooling propensity score matched cohorts.

RESULTS

Of the 229 records identified, 17 studies were included in the quantitative analysis. TDF treatment was associated with a significantly lower risk of HCC development [RR, 0.63; 95% confidence interval (CI), 0.43-0.93; P=0.024] and mortality (RR, 0.69; 95% CI, 0.57-0.84; P=0.003) than ETV treatment. Moreover, TDF significantly lowered HCC risk in patients with cirrhosis (RR, 0.69; 95% CI, 0.56-0.84) and antiviral treatment-naive patients (RR, 0.59; 95% CI, 0.35-0.98) compared with ETV. Among treatment-naive patients, TDF significantly prolonged survival compared with ETV (RR, 0.69; 95% CI, 0.52-0.91).

CONCLUSIONS

TDF likely confers a lower risk of HCC development and longer survival in patients with CHB, especially among treatment-naive patients and those with underlying cirrhosis, than ETV.

Clinical efficacy of antiviral therapy in patients with hepatitis B-related cirrhosis after transjugular intrahepatic portosystemic shunt

BACKGROUND

As a country with a high burden of hepatitis B, China has about 86 million cases of hepatitis B virus infection, ranking the first in the world. Currently, there are about 390000 deaths due to hepatitis B-related complications such as liver cirrhosis and liver cancer every year. Consequently, how to control portal hypertension, improve liver functional reserve, and reduce the incidence of hepatic failure and liver cancer in such patients is the focus of current clinical attention. Previous clinical study in our center suggested that at 24 mo after transjugular intrahepatic portosystemic shunt (TIPS), the liver functional reserve of patients with hepatitis B cirrhosis was better than that of patients with alcohol-induced and immune cirrhosis, which may be related to the effective etiological treatment.

AIM

To investigate the clinical efficacy of three first-line antiviral drugs recommended by the guidelines of prevention and treatment for chronic hepatitis B in China (2019) in the treatment of patients with hepatitis B-related cirrhosis who had received a TIPS.

METHODS

The clinical data of 137 patients with hepatitis B-related cirrhosis with portal hypertension after receiving TIPS at our centre between March 2016 and December 2020 were analysed retrospectively. According to different anti-viral drugs, the patients were divided into entecavir (ETV) (n = 70), tenofovir alafenamide fumarate (TAF) (n = 32), and tenofovir disoproxil fumarate (TDF) (n = 35) groups. The cumulative incidence of hepatic encephalopathy and hepatocellular carcinoma, survival, and changes in hepatic reserve function and glomerular filtration rate in patients treated with different antiviral drugs within 24 mo after surgery were investigated.

RESULTS

At 24 mo after surgery, the Child-Pugh score in the TAF group (6.97 ± 0.86) was lower than that in the TDF (7.49 ± 0.82; t = -2.52, P = 0.014) and ETV groups (7.64 ± 1.17; t = -2.92, P = 0.004). The model for end-stage liver disease score in the TAF group at 24 mo after surgery was 9.72 ± 1.5, which was lower than that in the TDF (10.74 ± 2.33; t = -2.09, P = 0.040) and ETV groups (10.97 ± 2.17; t = -2.93, P = 0.004). At 24 mo after surgery, the estimated glomerular filtration rate (eGFR) in the TAF group (104.41 ± 12.54) was higher than that in the TDF (93.54 ± 8.97) and ETV groups (89.96 ± 9.86) (F = 21.57, P < 0.001).

CONCLUSION

At 24 mo after surgery, compared with TDF and ETV, TAF has significant advantages in the improvement of liver functional reserve and eGFR.

Hepatitis B virus genome diversity in adolescents: Tenofovir disoproxil fumarate treatment effect and HBeAg serocon version

More systematic analysis of hepatitis B virus (HBV) genome diversity, linked with tenofovir disoproxil fumarate (TDF) treatment and HBeAg seroconversion, are needed. GS-US-174-0115 was a double-blind, placebo-controlled, Phase 3, 192-week clinical trial that evaluated TDF in adolescents with chronic hepatitis B (CHB). HBV full-genome deep sequencing was performed using Illumina MiSeq at baseline (BL; n = 85), Week 8 (W8; n = 80), Week 72 (W72; PBO only, n = 42), and treatment-free follow-up (TDF only, n = 25). The viral diversity was calculated using Shannon entropy and population nucleotide diversity with a 2% variant cutoff. Our data showed (i) a higher viral diversity in the X region at baseline than the core/polymerase/surface regions, (ii) higher core/surface viral diversity at baseline for patients with seroconversion, (iii) an expected reduction in viral diversity after 8 weeks of TDF treatment, and (iv) a drop in viral diversity at W72 for patients receiving placebo with a seroconversion (n = 7). The higher viral diversity in X was associated with higher baseline alanine aminotransferase (ALT) levels (p < .001). Patients with greater reduction of diversity at W8 of TDF treatment had higher baseline ALT levels. For placebo patients who seroconverted, the drop in viral diversity at W72 (p = .04) coincided with reduction of serum HBV DNA (average change from baseline = -4.10 log10 copies/ml) and unique combinations of variants were enriched in a patient's viral population post seroconversion. The basal core promoter (BCP) variants, A1762T and G1764A, and the pC variant, G1896A, were most often enriched at or after seroconversion.

Entecavir vs Tenofovir in Hepatocellular Carcinoma Prevention in Chronic Hepatitis B Infection: A Systematic Review and Meta-Analysis

Entecavir (ETV) and tenofovir disoproxil fumarate (TDF) are recommended as first-line therapies for chronic hepatitis B (CHB) infection. Although both drugs reduce hepatocellular carcinoma (HCC) risk, their comparative effectiveness remains controversial. We aimed to determine whether TDF is superior to ETV in preventing HCC.

Clinical and occupational health management of healthcare workers living with chronic hepatitis B: UK policy and international comparisons

Hepatitis B virus (HBV) is a highly infectious bloodborne virus, which remains endemic in large geographic areas and represents a major global healthcare challenge. HBV transmission from healthcare workers, who perform exposure prone procedures (EPP), to patients is a recognized transmission risk, which varies widely globally. Although the risk is small in developed countries, it increases significantly in high-prevalent, low-resource countries, representing a major challenge to these healthcare systems and underlining the necessity for robust guidance to be in place. The HBV landscape has evolved as a result of global vaccination programs, implementation of standard precautions and the advent of new generation antiviral agents (3rd generation nucleos(t)ide analogues). In light of the progress in the field, the UK Advisory Panel for Healthcare Workers Infected with Bloodborne Viruses (UKAP) recently issued updated guidance, which essentially removes past barriers, restricting healthcare workers from performing EPPs solely on the basis of HBV DNA level, regardless of hepatitis B 'e' antigen and/or treatment status. Although the current recommendations remain conservative compared to those of other developed healthcare systems, UK practice is now in line with other high-income countries, while ensuring patient safety remains paramount, without unduly restricting HCWs from clinical practice. The current article presents the latest UKAP guidance, considers its implications for HCWs and compares it with the guidance from major international scientific societies and governing bodies.

The Application of Dynamic Uncertain Causality Graph Based Diagnosis and Treatment Unification Model in the Intelligent Diagnosis and Treatment of Hepatitis B

Although hepatitis B is widespread, it is hard to cure. This paper presents a new and more accurate model for the diagnosis and treatment of hepatitis B. Based on previous research, the diagnosis and treatment modes were combined into one. By adding more influencing factors and risk factors, the overall diagnosis and treatment model will be further expanded, and a richer and more detailed overall diagnosis and treatment model will be constructed. Reverse logic gates are used in the model to improve the accuracy of the treatment planning. The new unified model is more accurate in subdividing diagnosis results, and it is more flexible and accurate in providing dynamic treatment plans. The prediction process and the static diagnosis process of the model are symmetric, and the related sub-graph is symmetric in structure. In addition, an algorithm for predicting the response probability of treatment scheme is developed, so as to predict the subsequent treatment effects of the current treatment scheme, such as the probability of drug resistance. The results show that this method is more accurate than other available systems, and it has encouraging diagnostic accuracy and effectiveness, which provides a promising help for doctors in diagnosing hepatitis B.

3-year Treatment of Tenofovir Alafenamide vs. Tenofovir Disoproxil Fumarate for Chronic HBV Infection in China

BACKGROUND AND AIMS

Tenofovir alafenamide (TAF) has similar efficacy to tenofovir disoproxil fumarate (TDF) but with improved renal and bone safety in chronic hepatitis B patients studied outside of China. We report 3-year results from two phase 3 studies with TAF in China (Clinicaltrials.gov: NCT02836249 and NCT02836236).

METHODS

Chinese hepatitis B e antigen (HBeAg)-positive and -negative chronic hepatitis B patients with viremia and elevated alanine aminotransferase were randomized 2:1 to TAF or TDF treatment groups and treated in a double-blind fashion for 144 weeks (3 years). Efficacy responses were assessed by individual study while safety was assessed by a pooled analysis.

RESULTS

Of the 334 patients (180 HBeAg-positive and 154 HBeAg-negative) randomized and treated, baseline characteristics were similar between groups. The overall mean age was 38 years and 73% were male. The mean HBV DNA was 6.4 log₁₀ IU/mL. The median alanine aminotransferase was 88 U/L, and 37% had a history of antiviral use. At week 144, the proportion with HBV DNA <29 IU/mL was similar among the two groups, with TAF at 83% vs. TDF at 79%, and TAF at 93% vs. TDF at 92% for the HBeAg-positive and -negative patients, respectively. In each study, higher proportions of TAF than TDF patients showed normalized alanine aminotransferase (via the American Association for the Study of Liver Diseases and the China criteria) and showed loss of HBsAg; meanwhile, the HBeAg seroconversion rates were similar. Treatment was well-tolerated among the TAF patients, who showed a smaller median decline in creatinine clearance (-0.4 vs. -3.2 mL/min; p=0.014) and less percentage change in bone mineral density vs. TDF at hip (-0.95% vs. -1.93%) and spine (+0.35% vs. -1.40%).

CONCLUSIONS

In chronic hepatitis B patients from China, TAF treatment provided efficacy similar to TDF but with better renal and bone safety at 3 years.

Recent Advances in Hepatitis B Treatment

Hepatitis B virus infection affects over 250 million chronic carriers, causing more than 800,000 deaths annually, although a safe and effective vaccine is available. Currently used antiviral agents, pegylated interferon and nucleos(t)ide analogues, have major drawbacks and fail to completely eradicate the virus from infected cells. Thus, achieving a "functional cure" of the infection remains a real challenge. Recent findings concerning the viral replication cycle have led to development of novel therapeutic approaches including viral entry inhibitors, epigenetic control of cccDNA, immune modulators, RNA interference techniques, ribonuclease H inhibitors, and capsid assembly modulators. Promising preclinical results have been obtained, and the leading molecules under development have entered clinical evaluation. This review summarizes the key steps of the HBV life cycle, examines the currently approved anti-HBV drugs, and analyzes novel HBV treatment regimens.

SASLT practice guidelines for the management of Hepatitis B virus - An update

Infection with hepatitis B virus (HBV) remains an important public health problem with a high burden worldwide. The Saudi Association for the Study of Liver diseases and Transplantation formed a working group to develop HBV practice guidelines in Saudi Arabia. The methodology used to develop these guidelines was based on reviewing the available evidence, local data, and major international practice guidelines on the management of HBV. The aim of these guidelines is to assist healthcare providers in the management of HBV in Saudi Arabia. These updated guidelines summarize the latest local studies performed on HBV epidemiology, major changes in the prevalence of this virus, and advances in disease management.

Entecavir resistance in a patient with treatment-naïve HBV: A case report

Among nucleos(t)ide analogue therapies for hepatitis B virus (HBV) treatment, entecavir (ETV) and tenofovir disoproxil fumarate (TDF)/tenofovir alafenamide are associated with the lowest rate of drug resistance. ETV is a drug requiring at least three substitutions in the reverse transcriptase (RT) domain to develop resistance, which is a rare occasion in treatment-naïve patients. However, pre-existing or acquired single mutations in the RT domain could lead to a virological breakthrough, after viral suppression. The present case report describes a 58-year-old female patient with hepatitis B virus (HBV) and high viral load who started HBV treatment with ETV. After 85 weeks of treatment, HBV-DNA declined to 0 IU/ml and remained undetectable for 3 years. However, after that period of time, the HBV-DNA rebounded, followed by the rise of liver enzymes (aspartate aminotransferase and alanine transaminase). Only the substitution M204I was detected in the HBV polymerase region. The patient was then switched to TDF treatment, achieving normalization of the liver enzymes and a decline in HBV-DNA levels. The present case report suggests that nucleoside-naïve patients should be cautiously monitored for resistance, even more than biochemically (transaminases, bilirubin) and virologically (HBV-DNA), even if complete HBV suppression is achieved.

Management of Hepatitis-B Virus Infection in Immunocompromised Children: A Single Center Experience

OBJECTIVES

The aims of the study was to expand the pediatric experience on hepatitis-B virus (HBV) reactivation, a known complication in patients with hematologic malignancies or on immunosuppression.

METHODS

Retrospective appraisal of HBV therapy/prophylaxis in immunocompromised children, studied from April 2006 to March 2020.

RESULTS

Eighteen HBV-positive patients, 5 girls, median age 11.1 (4.1--17.9) years were included. Seventeen of 18 were immunosuppressed at HBV-infection diagnosis. Seventeen were at high risk of reactivation, 1 at moderate risk. Five of 18 had acute hepatitis B as first infection or reactivation, 6 had HBeAg-positive infection, 1 an HBeAg-negative infection and 6 HBsAg-negative infection. Median follow-up was 2.7 (0.7--12.5) years. No HBV-related mortality was observed. Prophylaxis had to be repeated in 1. Lamivudine was used in 6/12 viremic patients and HBV-DNA negativization obtained in 2/6 (33%). Tenofovir-DF was used in 2/12 and entecavir in 4/12: 100% attained HBV-DNA negativization. Therapy had to be switched from tenofovir-DF to entecavir in 1 patient because of renal impairment. Virological breakthroughs were observed in 1 lamivudine-treated patient, leading to a hepatitis flare; 1 patient on entecavir had a hepatitis flare at immunoreconstitution. Mortality was 33% in the HBsAg-positive group. Seven prophylactic treatments were administered to 6 patients with HBsAg-negative infection: tenofovir-DF in 2 HBV-DNA-positive, lamivudine in 5 HBV-DNA-negative, without reverse HBsAg seroconversion, morbidity or mortality.

CONCLUSIONS

There is a residual risk of acute hepatitis B in immunocompromised children, mortality rate was substantial, potentially related to the delays in commencing chemotherapy caused by liver dysfunction. Tenofovir-DF or entecavir are the drugs of choice for HBV treatment in immunocompromised children.

Efficacy and Safety of Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Alafenamide as Maintenance Treatment in HIV/HBV-Coinfected Patients

BACKGROUND

The efficacy and safety of switching from tenofovir disoproxil fumarate-based antiretroviral therapy to coformulated elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide (E/C/F/TAF) has not been widely investigated in HIV/hepatitis B virus (HBV)-coinfected Asian population.

METHODS

Between February and October 2018, HIV/HBV-coinfected patients who had achieved HIV viral suppression with tenofovir disoproxil fumarate-containing regimens were switched to E/C/F/TAF. Assessments of plasma HBV and HIV viral load, HBV serology, renal function, lipid profiles, and bone mineral density (BMD) were performed at weeks 24 and 48 after switch.

RESULTS

A total of 274 HIV/HBV-coinfected participants were enrolled, with 12.8% testing HBeAg-positive and 94.2% having plasma HBV DNA <20 IU/mL at baseline. At weeks 24 and 48, 92.7% and 89.8% achieved plasma HBV DNA <20 IU/mL; 4.7% and 5.1% had HBV DNA ≥20 IU/mL; and 2.6% and 5.1% had no data, respectively. At weeks 24 and 48, 95.6% and 94.2% of participants maintained HIV RNA <50 copies/mL, respectively. Compared with baseline, the median urine β2-microglobulin-to-creatinine ratio at week 48 decreased significantly from 165 to 90 μg/g (P < 0.001). The mean BMD of the spine and hip improved at week 48 (+1.77% and +1.33%, respectively). Significantly higher lipid profiles were observed after switch to E/C/F/TAF. Thirteen (4.7%) patients withdrew from the study before week 48, with 7 (2.6%) patients because of adverse effects.

CONCLUSIONS

Switch to E/C/F/TAF maintained HBV and HIV viral suppression and resulted in the improvement of proteinuria and BMD of the spine and hip but increased lipid levels in HIV/HBV-coinfected patients at week 48.

The Occurrence of rtA194T Mutant After Long-Term Lamivudine Monotherapy Remains Sensitive to Tenofovir Disoproxil Fumarate: A Case Report

Tenofovir disoproxil fumarate (TDF) is recommended as first-line agents in chronic hepatitis B (CHB) patients for its high antiviral effects and high barrier to resistance. It is controversial whether the rtA194T mutation truly confers resistance against TDF. We present here a 62-year-old CHB patient who occurred rtL180M, rtM204V and rtA194T mutants after lamivudine (LAM) monotherapy for 9 years. TDF was introduced in replacement of LAM and led to Hepatitis B Virus (HBV) DNA undetectable in 1 month, maintained in the follow up of 52 weeks. These observations suggest that rtA194T mutation emerges under LAM monotherapy and remains sensitive to TDF.

Long-term efficacy and safety of nucleos(t)ides analogues in patients with chronic hepatitis B

Nucleos(t)ide analogues with high barrier to resistance are regarded as the principal therapeutic option for chronic hepatitis B (CHB). Treatment with entecavir (ETV), tenofovir disoproxil (TDF) and the later released tenofovir alafenamide (TAF) is highly effective at controlling hepatitis B virus (HBV) infection and, in the vast majority of patients, is well tolerated. No significant differences in viral suppression have been described among the different regimens, although an earlier achievement in biochemical response has been suggested first under TDF and recently under TAF. High barrier to resistance NAs rarely achieve hepatitis B surface antigen sero-clearance, and therefore should be maintained life-long in most cases. This has increased concerns about treatment-related toxicity, especially in patients under TDF with additional risk factors for kidney and bone impairment. TAF has shown a better bone and kidney safety profile than TDF, although it is not yet available worldwide due to its higher cost. Emergence of adverse events should be monitored since treatment-switch to ETV/TAF seems to be effective and safe in HBV mono-infected subjects. Finally, although an effective antiviral treatment leads to a clear improvement in clinical outcome of CHB patients; the risk of developing hepatocellular carcinoma (HCC) is not completely avoided with viral suppression. Whether tenofovir-based regimens provide any additional benefit over ETV in HCC prevention remains unclear and requires further investigation.

Distinctive HBV Replication Capacity and Susceptibility to Tenofovir Induced by a Polymerase Point Mutation in Hepatoma Cell Lines and Primary Human Hepatocytes

Tenofovir disoproxil fumarate (TDF) has been regarded as the most potent drug for treating patients with chronic hepatitis B (CHB). However recently, viral mutations associated with tenofovir have been reported. Here, we found a CHB patient with suboptimal response after more than 4 years of TDF treatment. Clonal analysis of hepatitis B virus (HBV) isolated from sequential sera of this patient identified the seven previously reported TDF-resistant mutations (CYELMVI). Interestingly, a threonine to alanine mutation at the 301 amino acid position of the reverse-transcriptase (RT) domain, (rtT301A), was commonly accompanied with CYELMVI at a high rate (72.7%). Since the rtT301A mutation has not been reported yet, we investigated the role of this naturally occurring mutation on the viral replication and susceptibility to tenofovir in various liver cells (hepatoma cells as well as primary human hepatocytes). A cell-based phenotypic assay revealed that the rtT301A mutation dramatically impaired the replication ability with meaningful reduction in sensitivity to tenofovir in hepatoma cell lines. However, attenuated viral replication by the rtT301A mutation was significantly restored in primary human hepatocytes (PHHs). Our findings suggest that the replication capability and drug sensitivity of HBV is different between hepatoma cell lines and PHHs. Therefore, our study emphasizes that validation studies should be performed not only in the liver cancer cell lines but also in the PHHs to understand the exact viral fitness under antiviral pressure in patients.

Effects of Tenofovir vs Entecavir on Risk of Hepatocellular Carcinoma in Patients With Chronic HBV Infection: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Tenofovir disoproxil fumarate (TDF) and entecavir are recommended as first-line treatments for chronic hepatitis B virus (HBV) infection. However, there is debate over the comparative effectiveness of these drugs in preventing hepatocellular carcinoma (HCC). We performed a systematic review and meta-analysis of the effectiveness of TDF vs entecavir in reducing the incidence of HCC among patients with chronic HBV infection.

METHODS

We performed a systematic review of the MEDLINE, EMBASE, Web of Science, and Cochrane Library from 2010 through 2019 for full-text articles and conference abstracts on studies of effects of TDF vs entecavir in patients with HBV infection. Extracted data were analyzed with the random-effects model. Potential sources of heterogeneity were investigated using sensitivity, meta-regression, and subgroup analyses.

RESULTS

Our final analysis comprised 15 studies (61,787 patients; 16,101 patients given TDF and 45,686 given entecavir). TDF treatment was associated with a significantly lower risk of HCC than entecavir (hazard ratio, 0.80; 95% CI, 0.69-0.93; P = .003; I2 = 13%). The lower risk of HCC in patients given TDF compared with entecavir persisted in sensitivity and subcohort analyses performed with propensity score-matched cohorts and cirrhosis subcohorts. Inclusion of patients with decompensated cirrhosis and the sample size were the factors with the largest effects on between-study heterogeneity in meta-regression analyses. Subsequent subgroup analyses showed no statistical differences in the incidence of death or transplantation (hazard ratio, 0.93; 95% CI, 0.73-1.17; P = .519; I2 = 6%) between patients given TDF vs entecavir.

CONCLUSIONS

In a meta-analysis of studies of patients with chronic HBV infection, we found that TDF treatment was associated with a significantly lower (20%) risk of HCC than entecavir treatment. Randomized trials are needed to support this finding.

Pharmacotherapy options for managing hepatitis B in children

INTRODUCTION

To eliminate viral hepatitis by 2030, the World Health Organization (WHO) launched the first global health sector strategy on viral hepatitis, with particular focus given to hepatitis B and C in 2016. To achieve the reduction of mortality in children, it is indispensable to know which children should be treated and how to treat them.

AREA COVERED

In this article, the authors review the antiviral treatment of children with chronic hepatitis B virus (HBV) infection including antivirals available for children with chronic HBV infection.

EXPERT OPINION

The approvals of nucleos(t)ide analogues (NAs) and pegylated interferon (PEG-IFN) for children have lowered a hurdle to the initiation of antiviral treatment in children. The international guidelines use nearly the same criteria of antiviral treatment for children with chronic HBV infection, but the WHO guidelines provide a cautious stance on the antiviral treatment of children. Not only PEG-IFN but also NAs with a high genetic barrier to drug resistance should be the first-line treatment for children. In settings with limited medical resources, NAs can be the first-line treatment for children. Although the concept of an 'immune-tolerant phase' is challenged, evidence is not sufficient to recommend the treatment of HBeAg-positive immune-tolerant children.

Characterization of Hepatitis B virus polymerase mutations A194T and CYEI and tenofovir disoproxil fumarate or tenofovir alafenamide resistance

Both the A194T and a quadruple mutation CYEI (S106C, H126Y, D134E and L269I) in hepatitis B virus (HBV) polymerase reverse transcriptase domain (pol/RT) are suggested to be associated with treatment failure with tenofovir disoproxil fumarate (TDF). To further evaluate this assertion, the prevalence of these mutations at baseline as well as their development and/or loss during TDF and tenofovir alafenamide (TAF) treatment was analysed in 3886 patients enrolled in Gilead HBV clinical studies. In total, six out of 3886 (0.2%) patients carried the rtA194T mutation, while only 1 patient carried a triple CYE and 2 patients carried a quadruple CYEI mutation at baseline. All the patients harbouring rtA194T or CYE/CYEI at baseline achieved viral suppression by week 96 after TDF or TAF treatment. No patients developed an rtA194T mutation or > 1 substitution of CYEI, and the number of patients losing any substitutions of CYEI (n = 17) was similar to the number who developed a single substitution of CYEI (n = 32) during treatment. Phenotypic evaluation of the site-directed mutant (SDM) panel containing these mutations with or without other resistance mutations did not demonstrate a significant shift in TFV and TAF potency in vitro. No evidence of rtA194T and CYEI conferring resistance to TDF or TAF was observed based on the treatment responses to TDF or TAF in patients with mutations at baseline, the lack of selection of mutations after starting TDF or TAF treatment and no change in susceptibility to TFV or TAF in vitro.

Efficacy and cost-effectiveness of antiviral regimens for entecavir-resistant hepatitis B: A systematic review and network meta-analysis

BACKGROUND

Chronic hepatitis B (CHB) patients who had exposed to lamivudine (LAM) and telbivudine (LdT) had high risk of developing entecavir (ETV)-resistance after long-term treatment. We aimed to conduct a systematic review and a network meta-analysis on the efficacy and cost-effectiveness on antiviral regimens in CHB patients with ETV-resistance.

DATA SOURCES

We searched PubMed, EMBASE and Web of Science for studies on nucleos(t)ide analogues (NAs) treatment [including tenofovir disoproxil fumarate (TDF)-based rescue therapies, adefovir (ADV)-based rescue therapies and double-dose ETV therapy] in CHB patients with ETV-resistance. The network meta-analysis was conducted for 1-year complete virological response (CVR) and biological response (BR) rates using GeMTC and ADDIS. A cost-effective analysis was conducted to select an economic and effective treatment regimen based on the 1-year CVR rate.

RESULTS

A total of 6 studies were finally included in this analysis. The antiviral efficacy was estimated. On network meta-analysis, the 1-year CVR rate in ETV-TDF [odds ratio (OR)  = 22.30; 95 % confidence interval (CI): 2.78-241.93], LAM-TDF (OR  = 70.67; 95 % CI: 5.16-1307.45) and TDF (OR  = 16.90; 95 % CI: 2.28-186.30) groups were significantly higher than that in the ETV double-dose group; the 1-year CVR rate in the LAM-TDF group (OR  = 14.82; 95 % CI: 1.03-220.31) was significantly higher than that in the LAM/LdT-ADV group. The 1-year BR rate of ETV-TDF (OR = 28.68; 95 % CI: 1.70-1505.08) and TDF (OR = 21.79; 95 % CI: 1.43-1070.09) therapies were significantly higher than that of ETV double-dose therapy. TDF-based therapies had the highest possibility to achieve the CVR and BR at 1 year, in which LAM-TDF combined therapy was the most effective regimen. The ratio of cost/effectiveness for 1-year treatment was 8 526, 17 649, 20 651 Yuan in the TDF group, TDF-ETV group, and ETV-ADV group, respectively.

CONCLUSIONS

TDF-based combined therapies such as ETV-TDF and LAM-TDF therapies were the first-line treatment if financial condition is allowed.

Developing a sensitive HBV genotyping assay for HBV DNA suppressed patients using both DNA and RNA sequencing

Hepatitis B virus (HBV) genotypes impact treatment outcomes and disease progression. The current genotyping methods have limitations in patients with low HBV viral load. In this study, a more sensitive assay has been developed for determining the HBV genotype in HBV DNA suppressed patients. Fifty-five serum samples from 55 chronic hepatitis B patients (HBeAg-, n = 20; HBeAg+, n = 35) across genotypes A to H with long-term nucleos(t)ide analogs (NAs) treatment were collected. All samples had HBV DNA less than 29 IU/mL. Total nucleic acid (viral DNA and RNA) was extracted and a 341 bp amplicon located at HBV S gene overlapping with reverse transcriptase domain of polymerase (pol/RT) was amplified via real time (RT)-nested polymerase chain reaction (PCR) followed by population sequencing. HBV genotype was determined by phylogenetic analysis. The assay successfully amplified HBV S/RT gene from 53 of 55 (96.4%) patient serum samples. Phylogenetic analysis demonstrated that the genotypes of all the 53 PCR positive samples matched the historical genotypes as determined by INNO-LiPA or RT sequence from the corresponding baseline samples. This assay was able to accurately determine HBV genotype irrespective of baseline genotype, HBeAg status, or duration of viral suppression. The ability to determine genotype in virally suppressed patients may facilitate the evaluation of novel treatment agents for HBV in this patient population.

The evolution and clinical impact of hepatitis B virus genome diversity

The global burden of hepatitis B virus (HBV) is enormous, with 257 million persons chronically infected, resulting in more than 880,000 deaths per year worldwide. HBV exists as nine different genotypes, which differ in disease progression, natural history and response to therapy. HBV is an ancient virus, with the latest reports greatly expanding the host range of the Hepadnaviridae (to include fish and reptiles) and casting new light on the origins and evolution of this viral family. Although there is an effective preventive vaccine, there is no cure for chronic hepatitis B, largely owing to the persistence of a viral minichromosome that is not targeted by current therapies. HBV persistence is also facilitated through aberrant host immune responses, possibly due to the diverse intra-host viral populations that can respond to host-mounted and therapeutic selection pressures. This Review summarizes current knowledge on the influence of HBV diversity on disease progression and treatment response and the potential effect on new HBV therapies in the pipeline. The mechanisms by which HBV diversity can occur both within the individual host and at a population level are also discussed.