Ten-year efficacy and safety of tenofovir disoproxil fumarate treatment for chronic hepatitis B virus infection

Safety and Effectiveness of Tenofovir Alafenamide in Usual Clinical Practice Confirms Results of Clinical Trials: TARGET-HBV

BACKGROUND

Nucleos(t)ide analogues, with a proven record of safety and efficacy, have been the therapy of choice for over a decade for the treatment of chronic hepatitis B. The approval of tenofovir alafenamide (TAF) in 2016 provided an additional treatment option.

AIMS

The aim of this study was to evaluate the characteristics and clinical outcomes of patients treated with TAF in usual clinical practice.

METHODS

Retrospective data from electronic health records was obtained from those enrolled in TARGET-HBV, a longitudinal observational cohort study of patients with chronic hepatitis B managed according to local practice standards at community and academic medical centers throughout the U.S.

RESULTS

Of 500 patients enrolled, most were male (66%) and of Asian race (66%) with median age of 55 years. Cirrhosis was evident in 15%. Most patients (82%) had switched to TAF after treatment with other antivirals. The perceived safety profile of TAF was cited as the primary reason for changing therapy (32%). TAF was well tolerated and only 4 patients discontinued therapy due to adverse event during a median duration of TAF dosing of 74 weeks. Among those with paired laboratory data 12-18 months after switching to TAF, biochemical response and HBV DNA suppression was maintained. Most patients had normal renal function which was essentially unchanged throughout follow-up.

CONCLUSIONS

TAF is frequently utilized in routine clinical practice due to the perception of its improved safety profile. The current study supports the growing body of evidence regarding the safety and effectiveness of TAF. Trial Registration ClinicalTrials.gov identifier: NCT03692897, https://clinicaltrials.gov/ct2/show/NCT03692897 .

How to achieve functional cure of HBV: Stopping NUCs, adding interferon or new drug development?

Functional cure of hepatitis B is defined as sustained undetectable circulating HBsAg and HBV DNA after a finite course of treatment. Barriers to HBV cure include the reservoirs for HBV replication and antigen production (covalently closed circular DNA [cccDNA] and integrated HBV DNA), the high viral burden (HBV DNA and HBsAg) and the impaired host innate and adaptive immune responses against HBV. Current HBV therapeutics, 1 year of pegylated-interferon-α (PEG-IFNα) and long-term nucleos(t)ide analogues (NUCs), rarely achieve HBV cure. Stopping NUC therapy may lead to functional cure in some Caucasian patients but rarely in Asian patients. Switching from a NUC to IFN after HBV DNA suppression increases the chance of HBsAg clearance mainly in those with low HBsAg levels. Novel antiviral strategies that inhibit viral entry, translation and secretion of HBsAg, modulate capsid assembly, or target cccDNA transcription/degradation have shown promise in clinical trials. Novel immunomodulatory approaches including checkpoint inhibitors, metabolic modulation of T cells, therapeutic vaccines, adoptive transfer of genetically engineered T cells, and stimulation of innate and B-cell immune responses are being explored. These novel approaches may be further combined with NUCs or PEG-IFNα in personalised strategies, according to virologic and disease characteristics, to maximise the chance of HBV cure. The development of curative HBV therapies should be coupled with the development of standardised and validated virologic and immunologic assays to confirm target engagement and to assess response. In addition to efficacy, curative therapies must be safe and affordable to meet the goal of global elimination of hepatitis B.

Management and Treatment of Patients with Chronic Hepatitis B: Towards Personalized Medicine

The currently available antiviral treatments (Peg-Interferon-α and Nucleos(t)ide Analogues, NA) for chronic hepatitis B (CHB) achieve a functional cure (serum HBsAg and HDV-DNA clearance) of HBV infection in a limited number of patients. Nevertheless, the continuous pharmacological suppression of viral replication by NA halts liver disease progression lowering the risk of HCC development and improving the survival. In the near future, to fully exploit the potential of old and new drugs for HBV treatment a personalized approach to the patients will be required according to an accurate definition of their virologic, immunologic and clinical profile.

HBsAg Loss as a Treatment Endpoint for Chronic HBV Infection: HBV Cure

Despite the availability of effective vaccines and antiviral therapy over the past two to three decades, chronic hepatitis B virus (HBV) infection remains a major global health threat as a leading cause of cirrhosis and liver cancer. Functional HBV cure defined as hepatitis B surface antigen (HBsAg) loss and undetectable serum HBV DNA is associated with improved clinical outcomes in patients with chronic HBV infection. However, spontaneous loss of HBsAg is rare and occurs in only 1% of all HBsAg-positive individuals annually. Furthermore, the rate of functional cure with currently available antiviral therapy is even lower, <1% patients on treatment per year. Nonetheless, HBsAg loss has become the new target or therapeutic endpoint for antiviral treatment. Recently, there has been much excitement surrounding the development of novel antiviral agents such as small interfering RNA (siRNA), core assembly modulators (CAMs), nucleic acid polymers (NAPs) among others, which may be used in combination with nucleos(t)ide analogs and possibly immunomodulatory therapies to achieve functional cure in a significant proportion of patients with chronic hepatitis B. Novel assays with improved sensitivity for detection of very low levels of HBsAg and to determine the source of HBsAg production will also be required to measure efficacy of newer antiviral treatments for HBV cure. In this narrative review, we will define HBV cure, discuss various sources of HBsAg production, evaluate rates of HBsAg loss with current and future antiviral agents, review clinical factors associated with spontaneous HBsAg loss, and explore clinical implications of functional cure.

Natural antibody IgG levels are associated with HBeAg-positivity and seroconversion in chronic hepatitis B patients treated with entecavir

B1 cell-derived natural antibodies are non-specific polyreactive antibodies and can activate the complement pathway leading to lysis of enveloped virus particles before activation of the adaptive immune response. We investigated the relationship between natural antibody levels and treatment outcomes of 126 treatment-naïve chronic hepatitis B (CHB) patients, who underwent entecavir (ETV) treatment. Serum IgG1-3 and complement C3 levels were significantly higher in HBeAg-positive patients. In pre-treatment, IgG1 (odd ratios [OR] 2.3, p < 0.0001), IgG2 (OR 9.8, p < 0.0001), IgG3 (OR 7.4, p < 0.0001), and C3 (OR 7.2, p < 0.0001) were associated with HBeAg-positive patients. At baseline, IgG2 (OR 10.2, p = 0.025), IgG4, (OR 3.4, p = 0.026), and complement C1q (OR 5.0, p = 0.0068) were associated with seroconverters. Post-treatment levels of IgG1-4 and C3/C1q were also associated with HBeAg-positive patients and seroconverters. High levels of IgG2-4 and C1q were observed in seroconverters but not in virological responders. Thus, high pretreatment and post-treatment levels of natural antibody IgG1-4, complement C3, and/or C1q were significantly associated with HBeAg-positivity and HBeAg seroconverters in CHB patients with ETV treatment. These results suggest that the presence of preexisting host immunity against chronic hepatitis B is closely related to outcome of ETV treatment.

Finite nucleos(t)ide analogue therapy in hepatitis B e antigen-negative chronic hepatitis B: From an "option" to an "active recommendation"

Nucleos(t)ide analogue (Nuc) including entecavir, tenofovir disoproxil fumarate, and tenofovir alafenamide may suppress hepatitis B virus (HBV) DNA profoundly but have no direct action on covalently closed circular DNA, which is a very stable template for HBV production. Therefore, decades of long-term Nuc therapy are required to maintain HBV suppression and to achieve hepatitis B surface antigen (HBsAg) loss in hepatitis B e antigen (HBeAg)-negative patients. However, there are concerns including financial burden, adherence, and willingness for indefinite long-term Nuc therapy. Patients lost to follow-up and hence not monitored may risk severe relapse that may deteriorate to hepatic decompensation or even hepatic failure. Cessation of Nuc therapy in HBeAg-negative patients was initially considered in early 2000s. Earlier findings in Asian patients that finite Nuc therapy over 2-3 years is feasible and safe have founded Asian-Pacific Association for the Study of Liver stopping rule since 2008. Subsequent studies have confirmed the feasibility and safety of the strategy of finite Nuc therapy, which has finally been accepted as "an option" by American and European liver associations since 2016. More recent large studies since 2018 have further confirmed the pivotal finding of greatly increased HBsAg loss rate (~5-year 39%) after stopping Nuc therapy. With the high HBsAg loss rate as the main justification, the paradigm shift from indefinite long-term therapy to finite Nuc therapy in HBeAg-negative patients has been changing from an "option" to an "active recommendation" aiming to achieve HBsAg loss. More studies are needed to fine-tuning the strategy, including research for the optimal duration of consolidation therapy, timing to stop, and to start retreatment.

Evaluation of Tenofovir Disoproxil Fumarate Treatment in Patients with Chronic Hepatitis B

Objective

The main purpose of chronic hepatitis B (CHB) treatment is to improve the patients' life quality and prevent the disease from progressing to cirrhosis or hepatocellular carcinoma. Continuous suppression of hepatitis B virus (HBV) DNA with nucleoside or nucleotide analogues is the most critical way to achieve this goal. This study aimed to evaluate the CHB patients retrospectively followed up with tenofovir disoproxil fumarate (TDF) treatment.

Materials and Methods

The study was planned as retrospective research by Afyonkarahisar Health Sciences University, Faculty of Medicine, Department of Infectious Diseases and Clinical Microbiology between January 2001 and December 2020. We evaluated all treatment-naive and treatment-experienced patients who received TDF (245 mg/day) treatment with the diagnosis of CHB. The data were obtained by reviewing the file information registered in the hospital automation system. HBsAg, Anti-HBs, HBeAg, Anti-HBe, HBV DNA, aspartate aminotransferase (AST), alanine aminotransferase (ALT) values of the patients were evaluated at 1st, 3rd, 6th, 12th months, and 6-month follow-ups throughout the treatment. Virological (HBV-DNA of < 50 IU/ml), biochemical (decrease below 40 IU/Ml in patients with pre-treatment value of ALT >40 IU/ml) and serological (Anti-HBe seroconversion in HBeAg positives and HBsAg negative and anti-HBs seroconversion in all patients) responses were examined. Adverse effects were also assessed during the treatment.

Results

Data from 131 patients who received TDF treatment were evaluated. Virological responses were determined as 78.6%, 81.3%, 94.2%, and 100% in the patients at 24th week, 48th week, 4th year, and 8th year, respectively. While there was no Anti-HBs seroconversion in any patients in four years of the treatment, it was observed at a rate of 10.5% in the eighth year. We did not determine any significant adverse effects requiring discontinuation of the treatment in the long-term follow-up of 131 patients under TDF treatment.

Conclusion

As a result of our study, TDF was an effective and well-tolerated choice for CHB treatment.

Safety of current antiviral drugs for chronic hepatitis B

INTRODUCTION

Oral nucleos(t)ide analogues (NUCs) are recommended as first-line therapy for chronic hepatitis B due to higher HBV-DNA suppression rates and safety profile. Long-term treatment with NUCs is often necessary to achieve durable viral suppression.

AREAS COVERED

This review provides an overview of the long-term safety data that have become available since entecavir (ETV) and tenofovir disoproxil fumarate (TDF) were first approved, and recent data on tenofovir alafenamide (TAF) in patients with CHB.

EXPERT OPINION

NUCs generally show remarkable safety in patients taking them for long periods. Nevertheless, renal and bone toxicity may occur in a minority of patients on TDF therapy. These effects have been overcome by the recent release of TAF. Moreover, the currently available data do not allow firm conclusions on superiority of TDF on ETV about HCC risk reduction. Observational studies involving more homogeneous cohorts are therefore needed; furthermore long-term studies assessing impact of TAF on this important topic are warranted.

Cost-savings and potential cost-savings through the distribution of generic antiretroviral drugs within the statutory health insurance market of Germany between January 2017 and June 2019

Abstract

Background

Recent patent losses for antiretroviral drugs (ARV) have led to the debate of cost-saving through the replacement of patented drugs with generic drugs. The split of recommended single-tablet regimens (STR) into their single substance partners is one of the considerations mentioned in said debate. Particularly, generic tenofovir disoproxil/emtricitabine (TDF/FTC) is expected to hold untapped cost-saving potential, which may curb increasing overall expenditures for combined antiretroviral therapy (cART) within the statutory health insurance (SHI) of Germany.

Methods

Data of ARV reimbursed by the SHI were used to describe the trends of defined daily doses (DDD) as well as the revenue within the German ARV market. They were also used to determine the cost-savings of moving to generic drugs. The time period observed was between January 2017 and June 2019. The potential cost-savings were determined with following assumption in mind: the maximum possible use of generic ARV, including 1) the split of STR and replacing all substance partners with generic ones, and 2) replacing patented tenofovir alafenamide/emtricitabine (TAF/FTC) with generic TDF/FTC.

Results

Throughout the observation period, the DDD of generic ARV increased nearly five-fold while their revenue increased more than four-fold. Total cost-saving showed a sharp increase over the same period, with generic TDF/FTC accounting for a share of around 70%. The largest potential cost-saving could have been achieved through replacing patented TAF/FTC with generic TDF/FTC, peaking at nearly 10% of total revenue, but showing decreasing trends in general.

Conclusion

The progressive distribution of generic ARV ensured increasing cost-savings_, but consequently curbed the potential cost-savings. Unique price reductions of generic TDF/FTC have played a pivotal role for these effects. In any case, substituting with generic ARV should not fail to adhere to the treatment guidelines and continue to consider the medical requirements for the treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-021-07390-4.

Comparison of Tenofovir Alafenamide and Entecavir Therapy in Patients with Chronic Hepatitis B Initially Treated with Tenofovir Disoproxil: A Retrospective Observational Survey

Background: In chronic hepatitis B patients with or exposed to the risk of osteoporosis or renal dysfunction, switching from tenofovir disoproxil fumarate (TDF) to tenofovir alafenamide fumarate (TAF) or entecavir (ETV) may be the right choice. Objectives: This study aimed to present real-life data in terms of the efficacy and safety of a TAF/ETV treatment change while receiving TDF. Methods: This retrospective study was conducted on 344 adult patients from 10 centers. The data of patients who had changed to ETV (n = 107) and TAF (n = 237) while receiving TDF were analyzed. The data collected at 0 and 6 months of treatment were analyzed. The virological response was assessed based on undetected hepatitis B virus (HBV) DNA. Serum alanine aminotransferase (ALT) values were used to evaluate the biochemical response. For renal function, serum creatinine and phosphorus, as well as estimated glomerular filtration rate (eGFR), were recorded. Moreover, lumbar spine and hip T-scores along with the serum lipid profile were evaluated. Results: The mean age of patients was 41.14 ± 13.46 years, and 224 (65.1%) of the participants were male. The treatment arms were not significantly different in terms of demographic characteristics, comorbid diseases, infection duration, family history of HBV infection, blood platelet count, serum biomarkers, such as ALT, phosphorus, creatinine, total bilirubin, albumin, lipid profile, and HBV DNA levels at the beginning. No statistically significant difference was found between the proportion of undetectable HBV DNA of the two treatment groups after 6 months (P = 0.221). The ALT normalization in the ETV and TAF groups at the sixth month compared to the baseline levels was not significantly different (P = 0.853, P = 0.330, respectively). There was no statistically significant difference between the two treatment arms regarding changes in eGFR, creatinine, phosphorus, hip, and spine T-scores from baseline to 6 months (P = 0.296, P = 0.78, P = 0.141, P = 0.832, P = 0.947, respectively). In those who switched to TAF or ETV, low-density lipoproteins cholesterol were observed to be significantly higher after 6 months compared to baseline values (P = 0.002, P = 0.049, respectively). The TC increased significantly in the TAF group (P = 0.035). Conclusions: Our study showed that switching to ETV and TAF sustained the viral suppression and biochemical response achieved by TDF therapy. The treatment switch to TAF of ETV can control renal dysfunction and reduce bone mineral density caused by TDF.

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.

Tenofovir disoproxil fumarate directly ameliorates liver fibrosis by inducing hepatic stellate cell apoptosis via downregulation of PI3K/Akt/mTOR signaling pathway

BACKGROUND

Antifibrotic agent for the treatment of liver fibrosis has not been developed so far. Long term treatment of chronic hepatitis B patients with antiviral drugs tenofovir disoproxil fumarate (TDF) and entecavir (ETV) results in the regression of liver fibrosis, but the underlying mechanism has not been clarified. Therefore, we aimed to investigate the direct impact of TDF and ETV on liver fibrosis.

METHODS

Activated hepatic stellate cell (HSC) cell lines were used to evaluate the effects of TDF and ETV. After treatment with each antiviral agent, cell viability, morphology, apoptotic features, autophagy and antifibrosis signalling pathways were examined. Then, collagen deposition, fibrosis markers and activated HSCs were measured in liver tissues of the liver fibrosis model mice.

RESULTS

After TDF treatment, the viabilities of LX2 and HSC-T6 cells were decreased, and the cells exhibited apoptotic features, but ETV did not induce these effects. Cleavage of PARP and Caspase-3 and the inhibition of the antiapoptotic gene Bcl-xl indicated activated HSC apoptosis following TDF treatment. TDF simultaneously increased autophagy, which also regulated apoptosis through crosstalk. TDF inactivated the PI3K/Akt/mTOR signalling pathway, which was associated with the activation of both apoptosis and autophagy. In the liver fibrosis mouse model, the fibrotic area and activated HSC markers were decreased by TDF but not ETV treatment. Additionally, apoptotic cells were concentrated in the periportal fibrotic area after TDF treatment, which indicated the specific antifibrotic effect of TDF.

CONCLUSIONS

TDF directly ameliorates liver fibrosis by downregulating the PI3K/Akt/mTOR signalling pathway, which results in the apoptosis of activated HSCs. The antifibrotic effects of TDF indicate that it may be a therapeutic agent for the treatment of liver fibrosis.

Efficacy and Safety of Tenofovir Disoproxil Orotate in Chronic Hepatitis B Patients Previously Treated with Tenofovir Disoproxil Fumarate: Multicenter, Open-Label, Prospective Study

Background/Aim: We aimed to demonstrate the efficacy and safety of tenofovir disoproxilorotate (TDO) compared with that of tenofovir disoproxil fumarate (TDF) in patients with chronic hepatitis B. Methods: This multicenter, open-label, prospective clinical trial (KCT0004185) was conducted to evaluate the efficacy and safety of TDO on switching from TDF for 24 weeks in virologically suppressed chronic hepatitis B patients. The primary efficacy endpoint was the maintenance of virologic response. Safety was assessed by evaluating major adverse events, changes in renal function, and occurrence of hepatocellular carcinoma (HCC). Results: TDO treatment was not inferior in terms of virological response when compared with that on TDF treatment, with a noninferiority margin of −10% (risk difference, −3.17%; 95% confidence interval, −7.5–1.15%). The biological response of TDO was also comparable to that of TDF, with no significant difference in the proportion of patients with normalized alanine transaminase levels. After 24 weeks of treatment, hepatitis B core-related antigen (HBcrAg) significantly decreased to a mean titer of 3.91 log U/mL from 4.15 log U/mL at baseline (p = 0.01). There were no cases of grade 3 or higher adverse events and HCC. The mean estimated glomerular filtration rate increased from 91.09 mL/min to 93.34 mL/min (p = 0.056), and the mean serum level of phosphorus increased from 3.33 mg/dL to 3.44 mg/dL (p = 0.045), suggesting improvement in renal function with TDO treatment. Conclusion: In patients with chronic hepatitis B, the efficacy of TDO was noninferior to that of TDF, with a significant decrease in the HBcrAg titer and improved renal function.

Potential Molecular Targets of Tenofovir Disoproxil Fumarate for Alleviating Chronic Liver Diseases via a Non-Antiviral Effect in a Normal Mouse Model

Accumulating evidence suggests that tenofovir disoproxil fumarate (TDF) can attenuate liver fibrosis directly, the mechanism of which, however, has not been fully elucidated, and there is a paucity of data concerning whether TDF can also mitigate other chronic liver diseases (CLDs). We aimed to identify the molecular targets and potential mechanism of TDF itself in ameliorating CLDs. RNA-sequencing was performed on mouse liver tissues treated with TDF or normal saline. Then the differentially expressed genes (DEGs) were screened, and enrichment analyses of the function and signaling pathways of DEGs were performed with Database for Annotation, Visualization, and Integrated Discovery (DAVID) and Metascape. Next, protein-protein interaction (PPI) networks were constructed and module analyses were utilized to identify significant genes. Subsequently, the DisGeNET platform was used to identify the potential target genes of TDF in mitigating these diseases. Finally, prediction of the transcription factors (TFs) and microRNAs (miRNAs) of the target genes was done to conjecture the underlying mechanism by which TDF relieved CLDs. As a result, a total of 854 DEGs were identified, and the DEGs were involved mainly in "immunity," "inflammation," and "metabolism" processes. In addition, 50 significant genes were obtained via PPI construction and module analyses. Furthermore, by means of DisGeNET, 19 genes (Adra2a, Cxcl1, Itgam, Cxcl2, Ccr1, Ccl5, Cxcl5, Fabp5, Sell, Lilr4b, Ccr2, Tlr2, Lilrb4a, Tnf, Itgb2, Lgals3, Cxcr4, Sucnr1, and Mme) were identified to be associated with nine CLDs. Finally, 34 miRNAs (especially mmu-miR-155-5p) and 12 TFs (especially Nfkb1) were predicted to be upstream of the nine target genes (Cxcl1, Cxcl2, Ccl5, Ccr2, Sell, Tlr2, Tnf, Cxcr4, and Mme) of TDF in ameliorating CLDs. In conclusion, our study suggests that TDF have the potential to ameliorate CLDs independently of its antiviral activity by affecting the expression of genes involved in hepatic immune, inflammatory, and metabolic processes via mmu-miR-155-5p-NF-κB signaling. These findings provided prima facie evidence for using TDF in CHB patients with concurrent CLDs.

Seroreversion of hepatitis B surface antigen among subjects with resolved hepatitis B virus infection: A community-based cohort study

BACKGROUND AND AIM

Hepatitis B virus (HBV) surface antigen (HBsAg) seroreversion usually occurs during immunosuppressive therapy. The risk and factors of HBsAg seroreversion from resolved HBV infection in the general population remained unclear.

METHODS

This retrospective study enrolled subjects with resolved HBV infection and who had received at least two times of screening in a longitudinal community screening program. HBsAg, hepatitis B surface antibody (anti-HBs), and hepatitis C virus antibody (anti-HCV) were tested every time in all subjects. The primary endpoint was HBsAg seroreversion.

RESULTS

Of the 7630 subjects enrolled, 5158 (67.6%) subjects had positive anti-HBs at baseline. HBsAg seroreversion occurred in 84 subjects during 42 815-person-year follow-up with an annual incidence of 0.2% and a 10-year cumulative risk of 1.9%. Anti-HBV treatment-experienced subjects had a significantly higher risk of HBsAg seroreversion than anti-HBV treatment-naive subjects (83/310 [26.8%] vs 1/7320 [0.01%], P < 0.001). Lower rates of positive anti-HBs and anti-HCV were observed in anti-HBV treatment-experienced subjects who developed HBsAg seroreversion. Both positive anti-HBs (hazard ratio/95% confidence interval: 0.56/0.348-0.903, P = 0.017) and positive anti-HCV (hazard ratio/95% confidence interval: 0.08/0.030-0.234, P < 0.001) were independent factors of HBsAg seroreversion in anti-HBV treatment-experienced subjects. Less than 5% of the HBsAg seroreverters had clinical hepatitis flare at HBsAg seroreversion. The HBsAg titer was low, and only transient reappeared in most of the HBsAg seroreverters.

CONCLUSIONS

Subjects with resolved HBV infection were at a minimal risk of HBsAg seroreversion, unless with prior anti-HBV treatment experience. Fortunately, even with a reappearance of HBsAg, it was transient and clinically non-relevant.

Randomised clinical trial: 48 weeks of treatment with tenofovir amibufenamide versus tenofovir disoproxil fumarate for patients with chronic hepatitis B

BACKGROUND

Tenofovir amibufenamide (TMF) can provide more efficient delivery than tenofovir disoproxil fumarate (TDF).

AIM

To compare the efficacy and safety of TMF and TDF for 48 weeks in patients with chronic hepatitis B (CHB).

METHODS

We performed a randomised, double-blind, non-inferiority study at 49 sites in China. Patients with CHB were assigned (2:1) to receive either 25 mg TMF or 300 mg TDF with matching placebo. The primary efficacy endpoint was the proportion of patients with hepatitis B virus (HBV) DNA less than 20 IU/mL at week 48. We also assessed safety, particularly bone, renal and metabolic abnormalities.

RESULTS

We randomised 1002 eligible patients. The baseline characteristics were well balanced between groups. After a median 48 weeks of treatment, the non-inferiority criterion was met in all analysis sets. In the HBeAg-positive population, 50.2% of patients receiving TMF and 53.7% receiving TDF achieved HBV DNA less than 20 IU/mL. In the HBeAg-negative population, 88.9% and 87.8%, respectively, achieved HBV DNA less than 20 IU/mL in the TMF and TDF groups. Patients receiving TMF had significantly less decrease in bone mineral density at both hip (P < 0.001) and spine (P < 0.001), and a smaller increase in serum creatinine at week 48 (P < 0.05). Other safety results were similar between groups.

CONCLUSION

TMF was non-inferior to TDF in terms of anti-HBV efficacy and showed better bone and renal safety. (NCT03903796).

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.

Should Treatment Indications for Chronic Hepatitis B Be Expanded?

BACKGROUND & AIM

Antiviral therapy has greatly improved the outcomes of patients with chronic hepatitis B virus (HBV) infection and active liver disease or advanced fibrosis/cirrhosis. However, current treatment does not eradicate HBV and long-term treatment is needed in most patients to maintain clinical benefit. Thus, professional society guidelines do not recommend treatment of all patients with chronic HBV infection. This review article will examine evidence for and against expansion of treatment to patients in whom treatment is not recommended based on current guidelines.

RESULTS

Available data support expanding treatment to immune tolerant patients and patients in the grey zones who have evidence of active/advanced liver disease based on liver biopsy or non-invasive tests and those who remain in the immune tolerant phase after age 40. Evidence supporting treatment expansion to confirmed inactive carriers and other immune tolerant patients is lacking.

CONCLUSIONS

HBV treatment indications can be more liberal when new therapies that can achieve HBsAg loss safely in a high percentage of patients after a finite course of treatment are available.

Discontinuation of antiviral therapy in chronic hepatitis B patients

Nucleos(t)ide analogs (NUC) are the first-line therapy for patients with chronic hepatitis B (CHB) recommended by most current guidelines. NUC therapy decreases progression of liver disease, reduces the risk of liver-related complications, and improves the quality of life of patients with CHB. Although indefinite or long-term NUC therapy is usually recommended, this strategy raises several concerns, such as side-effects, adherence, costs, and patient willingness to stop therapy. Recent data showed the feasibility, efficacy, and safety of stopping antiviral therapy in carefully selected CHB patients, leading to its incorporation in international guidelines. Patients who discontinue NUC have a higher likelihood of hepatitis B surface antigen (HBsAg) loss compared to patients who continue on therapy. Recommendations pertaining endpoints allowing safety discontinuation of NUC therapy differ among international guidelines. For hepatitis B e antigen (HBeAg)-positive patients, durable HBeAg seroconversion is considered an acceptable treatment endpoint. For HBeAg-negative patients, some guidelines propose undetectability hepatitis B virus DNA for at least 2 or 3 years, while others consider HBsAg loss as the only acceptable endpoint. CHB patients who stop therapy should remain under strict clinical and laboratorial follow-up protocols to detect and manage relapses in a timely manner. No reliable predictor of relapse has been consistently identified to date, although quantitative HBsAg has been increasingly studied as a reliable biomarker to predict safe NUC discontinuation.

Finite Antiviral Therapy in Chronic Hepatitis B Patients with Cirrhosis

Antiviral therapy has greatly improved the survival and reduced the incidence of adverse liver events such as hepatic decompensation and hepatocellular carcinoma in chronic hepatitis B patients with cirrhosis (hepatitis B virus [HBV]-cirrhosis). However, hepatitis B surface antigen loss, regarded as the ultimate goal of therapy or functional cure, was rarely achieved during long-term indefinite nucleos(t)ide analogues (Nuc) treatment. Emerging issues such as medication adherence and loss-to-follow-up may lead to increased risk of hepatic decompensation, even catastrophic life-threatening events. Studies have shown that finite therapy is feasible and reasonably safe, even in patients with HBV-cirrhosis. This review critically assesses the scientific evidence of the pros and cons for finite Nuc therapy in HBV-cirrhosis and proposes how to stop Nuc therapy and monitor the off-therapy patients. It also proposes the perspective and unsolved issues to be investigated in the future.

APASL guidance on stopping nucleos(t)ide analogues in chronic hepatitis B patients

Chronic hepatitis B virus (HBV) infection is currently incurable. Long-term treatment with potent and safe nucleos(t)ide analogs (NAs) can reduce hepatocellular carcinoma (HCC) and cirrhosis-related complications through profound viral suppression. However, indefinite therapy raises several crucial issues with pros and cons. Because seroclearance of hepatitis B surface (HBsAg) as functional cure is not easily achievable, a finite therapy including sequential 48-week pegylated interferon therapy may provide an opportunity to facilitate HBsAg seroclearance by the rejuvenation of exhausted immune cells. However, the cost of stopping NA is the high incidence of virological relapse and surge of alanine aminotransferase (ALT) levels, which may increase the risk of adverse outcomes (e.g., decompensation, fibrosis progression, HCC, or liver-related mortality). So far, the APASL criteria to stop NA treatment is undetectable HBV DNA levels with normalization of ALT; however, this criterion for cessation of treatment is associated with various incidence rates of virological/clinical relapse and more than 40% of NA-stoppers eventually receive retreatment. A very intensive follow-up strategy and identification of low-risk patients for virological/clinical relapse by different biomarkers are the keys to stop the NA treatment safely. Recent studies suggested that decreasing HBsAg level at the end-of-treatment to < 100-200 IU/mL seems to be a useful marker for deciding when to discontinue NAs therapy. In addition, several viral and host factors have been reviewed for their potential roles in predicting clinical relapse. Finally, the APASL guidance has proposed rules to stop NA and the subsequent follow-up strategy to achieve a better prognosis after stopping NA. In general, for both HBeAg-positive and HBeAg-negative patients who have stopped treatment, these measurements should be done every 1-3 months at the minimum until 12 months.

Functional Cure of Hepatitis B Virus Infection in Individuals With HIV-Coinfection: A Literature Review

In individuals infected with hepatitis B virus (HBV), the loss of hepatitis B surface antigen (HBsAg) is the ultimate therapeutic goal, which defines "functional cure." For individuals living with human immunodeficiency virus (HIV), functional cure occurs roughly 2 per 100 person-years during potent anti-HBV containing antiretroviral therapy. Although this rate may be higher than expected in treated HBV mono-infected individuals, rates of functional cure widely vary between studies (0.6-10.5 per 100 person-years). Similar to HBV mono-infection, the phase of HBV infection, HBV (sub-)genotypes and hepatitis B "e" Ag-negative variants are associated with functional cure in treated HIV-HBV co-infection. In specifically HIV-HBV co-infected individuals, strong increases in CD4+ T cell counts after treatment initiation have also been linked to functional cure, yet this finding is inconsistent across studies. Several markers directly or indirectly reflecting HBV activity are being developed to predict functional cure, such as quantification of HBsAg, hepatitis B core-related antigen, HBsAg protein composition, anti-hepatitis B core antibodies and interferon-gamma-inducible protein 10. Few have been assessed during treatment in HIV-HBV co-infected individuals and none have been validated to predict functional cure. Novel therapeutics for HBV cure are essential for individuals with HIV-HBV co-infection and need to be separately evaluated in this population.

Advances in treatment and prevention of hepatitis B

Chronic hepatitis B (CHB) continues to contribute to worldwide morbidity and mortality significantly. Scientists, clinicians, pharmaceutical companies, and health organizations have dedicated substantial Intellectual and monetary resources to finding a cure, increasing immunization rates, and reducing the global burden of CHB. National and international health-related organizations including the center for disease control, the national institute of health, the American Association for the study of liver disease (AASLD), The European association for the study of the Liver (EASL), The Asia Pacific association for the study of the Liver (APASL) and the world health organization release periodic recommendations for disease prevention and treatment. Our review of the most recent guidelines by EASL, AASLD, APASL, and Taiwan Association for the Study of the Liver revealed that an overwhelming majority of cited studies were published before 2018. We reviewed Hepatitis B-related literature published 2018 onwards to identify recent developments and current barriers that will likely direct future efforts towards eradicating hepatitis B. The breakthrough in our understanding of the hepatitis B virus life cycle and resulting drug development is encouraging with significant room for further progress. Data from high-risk populations, most vulnerable to the devastating effects of hepatitis B infection and reactivation remain sparse. Utilization of systems approach, optimization of experimental models, identification and validation of next-generation biomarkers, and precise modulation of the human immune response will be critical for future innovation. Within the foreseeable future, new treatments will likely complement conventional therapies rather than replace them. Most Importantly, pragmatic management of CHB related population health challenges must be prioritized to produce real-world results.

Hepatitis B virus (HBV) viral load, liver and renal function in adults treated with tenofovir disoproxil fumarate (TDF) vs. untreated: a retrospective longitudinal UK cohort study

BACKGROUND

Current clinical guidelines recommend treating chronic hepatitis B virus (HBV) infection in a minority of cases, but there are relatively scarce data on evolution or progression of liver inflammation and fibrosis in cases of chronic HBV (CHB) that do not meet treatment criteria. We aimed to assess the impact of TDF on liver disease, and the risk of renal impairment in treated CHB patients in comparison to untreated patients.

METHODS

We studied a longitudinal ethnically diverse CHB cohort in the UK attending out-patient clinics between 2005 and 2018. We examined TDF treatment (vs. untreated) as the main exposure, with HBV DNA viral load (VL), ALT, elastography scores and eGFR as the main outcomes, using paired tests and mixed effects model for longitudinal measurements. Additionally, decline of eGFR during follow-up was quantified within individuals by thresholds based on clinical guidelines. Baseline was defined as treatment initiation for TDF group and the beginning of clinical follow-up for untreated group respectively.

RESULTS

We included 206 adults (60 on TDF, 146 untreated), with a median ± IQR follow-up duration of 3.3 ± 2.8 years. The TDF group was significantly older (median age 39 vs. 35 years, p = 0.004) and more likely to be male (63% vs. 47%, p = 0.04) compared to the untreated group. Baseline difference between TDF and untreated groups reflected treatment eligibility criteria. As expected, VL and ALT declined significantly over time in TDF-treated patients. Elastography scores normalised during treatment in the TDF group reflecting regression of inflammation and/or fibrosis. However, 6/81 (7.4%) of untreated patients had a progression of fibrosis stage from F0-F1 to F2 or F3. There was no evidence of difference in rates or incidence of renal impairment during follow-up in the TDF vs. untreated group.

CONCLUSIONS

Risk of liver inflammation and fibrosis may be raised in untreated patients compared to those receiving TDF, and TDF may benefit a larger percentage of the CHB population.

Nucleos(t)ide analogue therapy: The role of tenofovir alafenamide

Chronic hepatitis B virus (HBV) infection remains an important global health problem, and may be difficult to manage in clinical practice. Nucleos(t)ide analogues (NAs) with a high barrier to resistance (entecavir [ETV], tenofovir disoproxil fumarate [TDF] and tenofovir alafenamide [TAF]) are the most frequently used HBV treatments because of their long-term effectiveness and tolerability. ETV may be less effective in patients with lamivudine-resistant strains, and TDF is associated with impaired renal function and reductions in bone mineral density. TAF, a new tenofovir prodrug, has been developed to overcome the less favourable safety profile of TDF. TAF is more stable in plasma, and higher tenofovir levels are achieved within cells at lower doses than with TDF. Several registration and real-life studies, performed up to week 144 of treatment, have shown that TAF is at least as effective as TDF, with higher rates of ALT normalization and significantly fewer kidney disturbances and changes in bone mineral density. No emergence of drug resistance has been found with TAF use. The main limitation to prescribing TAF is its price. The European Association for the Study of the Liver has suggested selecting TAF or ETV instead of TDF in patients >65 years old and in those with a risk of osteoporosis or renal abnormalities, and to prescribe TAF rather than ETV in patients previously exposed to NAs.

Viral and immune factors associated with successful treatment withdrawal in HBeAg-negative chronic hepatitis B patients

BACKGROUND & AIMS

Factors associated with a successful outcome upon nucleos(t)ide analogue (NA) treatment withdrawal in HBeAg-negative chronic hepatitis B (CHB) patients have yet to be clarified. The objective of this study was to analyse the HBV-specific T cell response, in parallel with peripheral and intrahepatic viral parameters, in patients undergoing NA discontinuation.

METHODS

Twenty-seven patients without cirrhosis with HBeAg-negative CHB with complete viral suppression (>3 years) were studied prospectively. Intrahepatic HBV-DNA (iHBV-DNA), intrahepatic HBV-RNA (iHBV-RNA), and covalently closed circular DNA (cccDNA) were quantified at baseline. Additionally, serum markers (HBV-DNA, HBsAg, HBV core-related antigen [HBcrAg] and HBV-RNA) and HBV-specific T cell responses were analysed at baseline and longitudinally throughout follow-up.

RESULTS

After a median follow-up of 34 months, 22/27 patients (82%) remained off-therapy, of whom 8 patients (30% of the total cohort) lost HBsAg. Baseline HBsAg significantly correlated with iHBV-DNA and iHBV-RNA, and these parameters were lower in patients who lost HBsAg. All patients had similar levels of detectable cccDNA regardless of their clinical outcome. Patients achieving functional cure had baseline HBsAg levels ≤1,000 IU/ml. Similarly, an increased frequency of functional HBV-specific CD8+ T cells at baseline was associated with sustained viral control off treatment. These HBV-specific T cell responses persisted, but did not increase, after treatment withdrawal. A similar, but not statistically significant trend, was observed for HBV-specific CD4+ T cell responses.

CONCLUSIONS

Decreased cccDNA transcription and low HBsAg levels are associated with HBsAg loss upon NA discontinuation in patients with HBeAg-negative CHB. The presence of functional HBV-specific T cells at baseline are associated with a successful outcome after treatment withdrawal.

LAY SUMMARY

Nucleos(t)ide analogue therapy can be discontinued in a high proportion of chronic hepatitis B patients without cirrhosis. The strength of HBV-specific immune T cell responses may contribute to successful viral control after antiviral treatment interruption. Our comprehensive study provides in-depth data on virological and immunological factors than can help guide individualised therapy in patients with chronic hepatitis B.

Continuing besifovir dipivoxil maleate versus switching from tenofovir disoproxil fumarate for treatment of chronic hepatitis B: Results of 192-week phase 3 trial

BACKGROUND/AIMS

Besifovir dipivoxil maleate (BSV), an acyclic nucleotide phosphonate, shows potent antiviral activity against hepatitis B virus. Our previous 48-week trial revealed that BSV has comparable antiviral efficacy to tenofovir disoproxil fumarate (TDF) and better safety profiles in terms of improved renal and bone safety. This extension study evaluated the prolonged efficacy and safety of BSV in treatment-naive chronic hepatitis B patients.

METHODS

Patients continued to participate in an open-label BSV study after an initial 48-week double-blind comparison of BSV and TDF treatment. The antiviral efficacy and drug safety was evaluated up to 192 weeks in two groups: patients continuing BSV treatment (BSV-BSV) and patients switching from TDF to BSV after 48 weeks (TDF-BSV).

RESULTS

Among 197 patients receiving randomized treatments, 170 (86%) entered the open-label phase and 152 (77%) entered the 192-week extension study. Virological response rates over 192 weeks were 92.50% and 93.06% in the BSV-BSV and TDF-BSV groups, respectively (P=0.90). Hepatitis B envelop antigen seroconversion and alanine aminotransferase normalization rates were similar between the groups (P=0.75 and P=0.36, respectively). There were no drug-resistant mutations to BSV. Bone mineral density and renal function were well preserved in the BSV-BSV group, whereas these initially worsened then recovered after switching therapy in the TDF-BSV group.

CONCLUSION

BSV maintained potent antiviral efficacy after 192 weeks and showed no evidence of drug resistance. BSV was safe, well tolerated, and effective in patients who switched from TDF to BSV. Trial Registration Number: NCT01937806 (date: 10 Sep 2013).

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.

Composition of HBsAg is predictive of HBsAg loss during treatment in patients with HBeAg-positive chronic hepatitis B

BACKGROUND & AIMS

During treatment of chronic HBV infections, loss or seroconversion of the HBV surface antigen (HBsAg) is considered a functional cure. HBsAg consists of the large (LHBs), middle (MHBs), and small surface protein (SHBs) and their relative proportions correlate strongly with disease stage. Our aim was to assess the association between HBsAg composition and functional cure during treatment.

METHODS

A total of 83 patients were retrospectively analyzed. HBsAg loss was achieved by 17/64 patients during nucleos(t)ide analogue (NA) treatment and 3/19 patients following treatment with pegylated interferon-alfa2a (PEG-IFN) for 48 weeks. Sixty-three patients without HBsAg loss were matched as controls. LHBs, MHBs and SHBs were quantified in sera collected before and during treatment.

RESULTS

Before treatment, median MHBs levels were significantly lower in patients with subsequent HBsAg loss than in those without (p = 0.005). During treatment, MHBs and LHBs proportions showed a fast decline in patients with HBsAg loss, but not in patients with HBV e antigen seroconversion only or patients without serologic response. MHBs became undetectable by month 6 of NA treatment in all patients with HBsAg loss, which occurred on average 12.8 ± 8.7 (0-52) months before loss of total HBsAg. Receiver-operating characteristic analyses revealed that the proportion of MHBs was the best early predictor of HBsAg loss before NA treatment (AUC = 0.726, p = 0.019). In patients achieving HBsAg loss with PEG-IFN, the proportions of MHBs and LHBs showed similar kinetics.

CONCLUSION

Quantification of HBsAg proteins shows promise as a novel tool to predict early treatment response. These assessments may help optimize individual antiviral treatment, increasing the rates of functional cure in chronically HBV-infected patients.

LAY SUMMARY

The hepatitis B surface antigen (HBsAg) is a key serum marker for viral replication. Loss of HBsAg is considered stable remission, which can be achieved with antiviral treatments. We have investigated whether the ratios of the different components of HBsAg, namely the large (LHBs) and medium (MHBs) HBsAg during different treatments are associated with the occurrence of HBsAg loss. We found that LHBs and MHBs decrease earlier than total HBsAg before HBsAg loss and we propose LHBs and MHBs as promising novel biomarker candidates for predicting cure of HBV infection.

Comparison of viral control between two tenofovir dose reduction regimens (300 mg every 48 hours versus 300 mg every 72 hours) in chronic hepatitis B patients with moderate renal impairment from tenofovir-induced renal dysfunction

Long-term use of tenofovir disoproxil fumarate (TDF) can induce renal dysfunction that requires TDF dose reduction. Previous studies showed that systemic drug use exerts a threefold higher risk of moderate renal impairment. This study aimed to compare viral control between two tenofovir dose reduction regimens in chronic hepatitis B (CHB) patients with moderate renal impairment from TDF-induced renal dysfunction. This noninferiority, randomized controlled study was conducted at the Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand. Virologically suppressed CHB patients treated with TDF who had moderate renal impairment were randomly allocated to receive TDF 300 mg either every 48 or 72 hours. Forty-six patients (67.4% male) with a mean age of 62.8 ± 7.8 years were enrolled. Among all patients, 34.8% were HBeAg-positive, and 23.9% had cirrhosis. All included patients completed 12 months of follow-up. No patients had virological breakthrough. After dose reduction, estimated glomerular filtration rate (eGFR) was improved in both groups, but a higher proportion of patients had an eGFR > 60 mL/min/1.73 m² in the TDF every 72 hours group. Other renal parameters, including serum phosphate, tubular maximal reabsorption for phosphate per GFR, urine protein-to-creatinine ratio, urine sugar and urine neutrophil gelatinase-associated lipocalin, were not significantly different between groups. Among TDF-treated CHB patients with TDF-induced moderate renal impairment, more aggressive dose reduction in TDF from every 48 hours to every 72 hours did not affect virological breakthrough. A higher proportion of patients in the TDF every 72 hours group had improvement in renal function.

Long-term clinical outcome of HBeAg-negative chronic hepatitis B patients who discontinued nucleos(t)ide analogues

BACKGROUND & AIMS

Discontinuation of nucleos(t)ide analogues (NA) remains a debatable issue in HBeAg-negative chronic hepatitis B (CHB). This study aimed to address the outcome of HBeAg-negative CHB patients who discontinued NA therapy.

METHODS

This prospective study included 57 non-cirrhotic HBeAg-negative Caucasian CHB patients who discontinued NA therapy after median virological remission of 6 years. All patients had regular blood tests. Virological relapse was defined as HBV DNA > 2000 IU/mL or >20 000 IU/mL and biochemical relapse as ALT > ULN (40 IU/mL) or >2xULN. All patients with retreatment predefined criteria restarted entecavir or tenofovir.

RESULTS

Of the 57 patients, 29 remained without retreatment after median follow-up of 65 months (range: 36-87) following treatment discontinuation. At 3, 6, 12, 24, 36 and 48 months, cumulative rates of retreatment were 16%, 20%, 32%, 35%, 46% and 50%, while the proportion of patients with HBV DNA < 2000 IU/mL and ALT < ULN were 73%, 60%, 52%, 52%, 47% and 37% respectively. All patients had virological and biochemical response after retreatment. No patient developed liver failure, hepatocellular carcinoma or death. Cumulative rates of HBsAg loss were 2%, 4%, 7%, 10% and 20% at 3, 6, 12, 24 and 36 months. HBsAg levels < 100 IU/mL at the end of NA treatment could predict HBsAg loss (P = .001).

CONCLUSIONS

Our study supports that NA therapy can be safely stopped in non-cirrhotic patients with HBeAg-negative CHB. Over a median follow-up of more than 5 years, half of the patients remained without retreatment with a substantial proportion of them achieving functional cure.

New Insights on Long-Term Hepatitis B Virus Responses in HIV-Hepatitis B virus Co-infected Patients: Implications for Antiretroviral Management in Hepatitis B virus-Endemic Settings

BACKGROUND

WHO treatment guidelines recommend tenofovir plus lamivudine or emtricitabine as the nucleoside reverse transcriptase inhibitor backbone in first-line regimens for HIV-infected adults. Lamivudine alone is not recommended, because of the risk of hepatitis B virus (HBV) resistance. We studied HBV responses in a large cohort of co-infected patients in a resource-limited setting.

SETTING

Clinical centers in Uganda and Zimbabwe.

METHODS

DART was a randomized trial of monitoring practices in HIV-infected adults starting antiretroviral therapy. Baseline samples were tested retrospectively for HBV serological markers and HBV DNA. Longitudinal HBV DNA testing at 48 weeks and the last available sample before HBV-relevant modification of antiretroviral therapy was performed on patients with detectable HBV DNA at baseline.

RESULTS

Two hundred twenty-four hepatitis B surface antigen-positive patients were followed for up to 4.8 years. Of the drugs with anti-HBV activity, 166 were prescribed lamivudine-tenofovir and 58 lamivudine alone. Ninety-eight percent (96/98) patients with baseline HBV DNA <6 log10 IU/mL achieved viral suppression at 48 weeks (HBV DNA <48 IU/mL), regardless of regimen, compared with 50%(26/52) for HBV DNA >6 log10 IU/mL. Of the 83 patients suppressed at 48 weeks and with follow-up data, only 7(8%) experienced viral rebound (range 200-3460 IU/mL). Of the 20 patients not suppressed at 48 weeks and with follow-up data, HBV DNA levels generally declined with lamivudine-tenofovir, but increased with lamivudine alone. Alanine transaminase flares were not observed in any patient who experienced viral rebound.

CONCLUSIONS

The suppressive effect of lamivudine alone was highly durable (up to 5 years) in HIV-HBV co-infected patients with baseline HBV DNA <6 log10 IU/mL. It may be feasible to develop stratified approaches using lamivudine as the only drug with anti-HBV activity.

aMAP risk score predicts hepatocellular carcinoma development in patients with chronic hepatitis

BACKGROUND & AIMS

Hepatocellular carcinoma (HCC) is the leading cause of death in patients with chronic hepatitis. In this international collaboration, we sought to develop a global universal HCC risk score to predict the HCC development for patients with chronic hepatitis.

METHODS

A total of 17,374 patients, comprising 10,578 treated Asian patients with chronic hepatitis B (CHB), 2,510 treated Caucasian patients with CHB, 3,566 treated patients with hepatitis C virus (including 2,489 patients with cirrhosis achieving a sustained virological response) and 720 patients with non-viral hepatitis (NVH) from 11 international prospective observational cohorts or randomised controlled trials, were divided into a training cohort (3,688 Asian patients with CHB) and 9 validation cohorts with different aetiologies and ethnicities (n = 13,686).

RESULTS

We developed an HCC risk score, called the aMAP score (ranging from 0 to 100), that involves only age, male, albumin-bilirubin and platelets. This metric performed excellently in assessing HCC risk not only in patients with hepatitis of different aetiologies, but also in those with different ethnicities (C-index: 0.82-0.87). Cut-off values of 50 and 60 were best for discriminating HCC risk. The 3- or 5-year cumulative incidences of HCC were 0-0.8%, 1.5-4.8%, and 8.1-19.9% in the low- (n = 7,413, 43.6%), medium- (n = 6,529, 38.4%), and high-risk (n = 3,044, 17.9%) groups, respectively. The cut-off value of 50 was associated with a sensitivity of 85.7-100% and a negative predictive value of 99.3-100%. The cut-off value of 60 resulted in a specificity of 56.6-95.8% and a positive predictive value of 6.6-15.7%.

CONCLUSIONS

This objective, simple, reliable risk score based on 5 common parameters accurately predicted HCC development, regardless of aetiology and ethnicity, which could help to establish a risk score-guided HCC surveillance strategy worldwide.

LAY SUMMARY

In this international collaboration, we developed and externally validated a simple, objective and accurate prognostic tool (called the aMAP score), that involves only age, male, albumin-bilirubin and platelets. The aMAP score (ranged from 0 to 100) satisfactorily predicted the risk of hepatocellular carcinoma (HCC) development among over 17,000 patients with viral and non-viral hepatitis from 11 global prospective studies. Our findings show that the aMAP score had excellent discrimination and calibration in assessing the 5-year HCC risk among all the cohorts irrespective of aetiology and ethnicity.

Tooth loss associated with the use of tenofovir disoproxil fumarate

WHAT IS KNOWN AND OBJECTIVE

The frequent tenofovir disoproxil fumarate (TDF)-related adverse drug reactions (ADRs) are nephrotoxicity and bone toxicity; however, tooth-related ADRs of TDF have not been reported. We describe the case of a 41-year-old Han Chinese man with chronic hepatitis B with TDF-associated tooth loss.

CASE SUMMARY

He presented with halitosis, gingival swelling and tooth loss after TDF use. After excluding the possibility of other drug-related ADRs, TDF was considered a possible cause and switched with tenofovir alafenamide fumarate (TAF). After 6 months, the oral symptoms disappeared, with no additional tooth loss.

WHAT IS NEW AND CONCLUSION

This is the first report of such ADRs. The ADR score was 7, indicating tooth loss as a potential TDF-related ADR.

Virology analysis of chronic hepatitis B virus-infected patients treated for 28 days with JNJ-56136379 monotherapy

Four weeks of once-daily oral JNJ-56136379 (JNJ-6379; 25, 75, 150 or 250 mg), a class-N capsid assembly modulator (CAM-N), was well tolerated with potent antiviral activity in treatment-naïve, chronic hepatitis B e antigen-positive and hepatitis B e antigen-negative patients (NCT02662712). Hepatitis B virus (HBV) genome sequence analysis, using HBV DNA next-generation sequence technology, was performed, and impact of substitutions on efficacy was assessed. Analyses focused on HBV core protein amino acid positions associated with JNJ-6379 and/or other CAMs in vitro resistance, and those within the CAM-binding pocket. 31/57 patients had ≥ 1 polymorphism at any of the core amino acid positions of interest, most frequently at positions 38 (32%), 105 (23%) and 109 (14%). None of these polymorphisms are known to reduce JNJ-6379 in vitro activity (fold change [FC] in 50% effective concentration <3.0). Two JNJ-6379-treated patients carried a Y118F baseline core polymorphism known to reduce JNJ-6379 activity in vitro (FC = 6.6) and had HBV DNA declines of 2.77 (75 mg) and 2.19 log₁₀ IU/mL (150 mg) at the end of treatment. One 75 mg JNJ-6379-treated patient had an emerging T109S substitution (FC = 1.8; HBV DNA decline 3.18 log₁₀ IU/mL). A 25 mg JNJ-6379-treated patient had on-treatment enrichment of Y118F variant (HBV DNA decline 2.13 log₁₀ IU/mL). In conclusion, baseline polymorphisms and enrichment of substitutions reducing JNJ-6379 in vitro activity were rare, with no consistent impact on virological response during a 4-week phase 1b study. Emergence of resistance to longer treatments of JNJ-6379 will be evaluated in phase 2 studies.

Application of EASL 2017 criteria for switching hepatitis B patients from tenofovir disoproxil to entecavir or tenofovir alafenamide

BACKGROUND

To overcome safety limitations of tenofovir-disoproxil, EASL guidelines proposed switching chronic hepatitis B patients older than 60 years or with bone or renal disease to tenofovir-alafenamide or entecavir.

AIMS

To estimate the number of patients who would benefit from a treatment switch in a real-life setting.

METHODS

Consecutive hepatitis B patients receiving tenofovir-disoproxil before 31 December 2017 were enrolled in a cross-sectional study in two European hospitals. Clinical and virological data were recorded; renal function was assessed by estimated glomerular filtrate rate, serum phosphate and creatinine, proteinuria, and albuminuria; bone involvement by spine and femur DEXA scan.

RESULTS

In total, 565 patients included: 62 (18-91) years, 75% males, 92% Caucasian, 92% HBeAg-negative, 40% cirrhotic. Fifty-five percent of patients fulfilled age criterion (>60 years). Older patients had higher rates of cirrhosis (51% vs 26%, p<0.001), cardiovascular disease, and renal impairment. Thirty-six percent of patients met renal criteria, more commonly NA-experienced individuals (35% vs 21%, p=0.001); 17% had bone disease. Overall, 66% of patients had at least one criterion (71% if NA-experienced), 8% all three criteria, 28% age and renal criteria.

CONCLUSIONS

Approximately two-thirds of patients receiving long-term tenofovir-disoproxil are candidates for an entecavir or tenofovir-alafenamide switch according to EASL recommendations.

Impact of Hepatitis B Virus Genetic Variation, Integration, and Lymphotropism in Antiviral Treatment and Oncogenesis

Chronic Hepatitis B Virus (HBV) infection poses a significant global health burden. Although, effective treatment and vaccinations against HBV are available, challenges still exist, particularly in the development of curative therapies. The dynamic nature and unique features of HBV such as viral variants, integration of HBV DNA into host chromosomes, and extrahepatic reservoirs are considerations towards understanding the virus biology and developing improved anti-HBV treatments. In this review, we highlight the importance of these viral characteristics in the context of treatment and oncogenesis. Viral genotype and genetic variants can serve as important predictive factors for therapeutic response and outcomes in addition to oncogenic risk. HBV integration, particularly in coding genes, is implicated in the development of hepatocellular carcinoma. Furthermore, we will discuss emerging research that has identified various HBV nucleic acids and infection markers within extrahepatic sites (lymphoid cells). Intriguingly, the presence of hepatocellular carcinoma (HCC)-associated HBV variants and viral integration within the lymphoid cells may contribute towards the development of extrahepatic malignancies. Improved understanding of these HBV characteristics will enhance the development of a cure for chronic HBV infection.

Consensus document of the Spanish Association for Study of the Liver on the treatment of hepatitis B virus infection (2020)

Hepatitis B virus (HBV) infection remains a global public health problem. HBV vaccination is the most effective tool to reduce the incidence of HBV disease. Despite there has not been new clinical developments for the treatment of chronic hepatitis B in the last few years, changing epidemiology and current insights on natural history, diagnostic tools and therapy indications make necessary an update of the former version of the consensus document of the Spanish Association for Study of the Liver on the treatment of hepatitis B infection published in 2012. The current document updates the management of chronic hepatitis B. The treatment of choice is the long-term administration of a nucleos(t)ide analogue with high barrier to resistance (entecavir, tenofovir or tenofovir alafenamide). Pegylated interferon may be an option in patients with non-advanced liver disease, but its applicability is limited due to the low efficacy and poor tolerability. All patients must be monitored for the risk of progression to advanced liver disease and development of hepatocellular carcinoma.

Evidence of tenofovir resistance in chronic hepatitis B virus (HBV) infection: An observational case series of South African adults

INTRODUCTION

Tenofovir disoproxil fumarate (TDF) is widely recommended for treatment of chronic hepatitis B virus (HBV) infection because it is safe, affordable and has a high genetic barrier to resistance. TDF resistance associated mutations (RAMs) have been reported, but data are limited, particularly for Africa. We set out to identify potential RAMs in individuals with detectable HBV viraemia on TDF treatment.

METHODS

We recruited adults with chronic HBV infection from Cape Town, South Africa, identifying individuals with a TDF resistance phenotype, defined as persistent HBV vireamia despite >12 months of TDF treatment. We sequenced HBV DNA using MiSeq Illumina with whole genome target enrichment, and sought potential TDF RAMs, based on a pre-defined list of polymorphisms.

RESULTS

Among 66 individuals with chronic HBV (genotypes A and D), three met our clinical definition for TDF resistance, of whom two were coinfected with HIV. In one participant, the consensus HBV sequence contained nine polymorphisms that have been described in association with TDF resistance. Significant treatment non-adherence in this individual was unlikely, as HIV RNA was suppressed. TDF RAMs were also present in HBV sequences from the other two participants, but other factors including treatment non-adherence may also have had a role in failure of HBV DNA suppression in these cases.

DISCUSSION

Our findings add to the evidence that RAMs in HBV reverse transcriptase may underpin a TDF resistant phenotype. This is the first time these RAMs have been reported from Africa in association with clinical evidence of TDF resistance.

Anti-HBV activity of the HBV capsid assembly modulator JNJ-56136379 across full-length genotype A–H clinical isolates and core site-directed mutants in vitro

Objectives

To characterize antiviral activity of the capsid assembly modulator (CAM-N) JNJ-56136379 against HBV genotypes and variants carrying amino acid substitutions in the core protein.

Methods

Anti-HBV activity of JNJ-56136379 was investigated against a diverse panel of 53 HBV clinical isolates (genotypes A–H). The impact of core amino acid substitutions using site-directed mutants (SDMs) was assessed in a transient replication assay.

Results

JNJ-56136379 median 50% effective concentration (EC50) values across all genotypes were 10–33 nM versus 17 nM (genotype D reference). JNJ-56136379 remained active against isolates carrying nucleos(t)ide analogue resistance mutations (median EC50 2–25 nM) or basal core promoter (BCP) ± precore (PC) mutations (median EC50 13–20 nM) or PC mutations (median EC50 11 nM), representing activity against isolates from HBeAg-positive and -negative hepatitis B patients. Core amino acid substitutions in the CAM-binding pocket, when tested as SDMs at positions 23, 25, 30, 33, 37, 106, 110, 118, 124, 127 and 128, reduced JNJ-56136379 anti-HBV activity; EC50 fold increases ranged from 3.0 (S106T) to 85 (T33N). All substitutions were rare in a public database of &gt;7600 HBV core sequences (frequencies 0.01%–0.3%). Nucleos(t)ide analogues retained full activity against these core SDMs.

Conclusions

JNJ-56136379, a potent HBV CAM-N, currently in Phase 2 clinical development, was generally fully active against an extensive panel of genotype A–H clinical isolates, regardless of the presence of nucleos(t)ide analogue resistance or BCP/PC mutations. JNJ-56136379 activity was reduced by some core amino acid substitutions in the CAM-binding pocket.

Switching from tenofovir disoproxil fumarate to tenofovir alafenamide in virologically suppressed patients with chronic hepatitis B: a randomised, double-blind, phase 3, multicentre non-inferiority study

BACKGROUND

Treatment with tenofovir disoproxil fumarate has been associated with renal toxicity or reductions in bone mineral density, or both, in some patients with chronic hepatitis B virus (HBV) infection. Tenofovir alafenamide is a tenofovir prodrug with high intrahepatic concentrations of active drug and reduced systemic tenofovir exposures compared with tenofovir disoproxil fumarate. In patients with chronic HBV, tenofovir alafenamide has shown efficacy non-inferior to that of tenofovir disoproxil fumarate with improved renal and bone safety. With this non-inferiority study, we aimed to evaluate the efficacy and safety of tenofovir alafenamide in patients with HBV infection switching from tenofovir disoproxil fumarate who are virally suppressed.

METHODS

Patients with chronic HBV infection who had been receiving tenofovir disoproxil fumarate for 48 weeks or more and who had HBV DNA less than the lower limit of quantification (LLOQ) for at least 12 weeks were recruited to this randomised, multicentre, double-blind, phase 3 non-inferiority study. Patients were randomly assigned in a 1:1 ratio to receive tenofovir alafenamide 25 mg once a day or to continue tenofovir disoproxil fumarate 300 mg once a day. The primary efficacy endpoint was loss of virological control, defined as the proportion of patients who received at least one dose of study drug who had HBV DNA of at least 20 IU/mL at week 48 by the modified US Food and Drug Administration (FDA) snapshot algorithm. Key safety endpoints were changes in hip and spine bone mineral density, estimated creatinine clearance by Cockcroft-Gault, and markers of bone turnover and renal tubular function. The study was powered for non-inferiority in efficacy of tenofovir alafenamide versus tenofovir disoproxil fumarate with a 4% margin. Investigators and patients were unaware of treatment allocation and on-treatment results. This trial is ongoing and is registered with ClinicalTrials.gov, number NCT02979613.

FINDINGS

Participants in this study were enrolled between Dec 29, 2016, and Oct 20, 2017. 541 patients were screened and 490 patients were randomly assigned to switch to tenofovir alafenamide or to stay on tenofovir disoproxil fumarate. Two patients assigned to receive tenofovir alafenamide did not receive treatment; thus the full analysis set for efficacy and safety analyses consisted of 243 patients in the tenofovir alafenamide group and 245 in the tenofovir disoproxil fumarate group. At week 48, one patient from each treatment group (both <1%) had HBV DNA of at least 20 IU/mL (difference in proportion 0·0%, 95% CI -1·9 to 2·0), thereby showing non-inferior efficacy of tenofovir alafenamide to tenofovir disoproxil fumarate. Patients who received tenofovir alafenamide had significantly increased bone mineral density at hip (mean change 0·66% [SD 2·08] vs -0·51% [SD 1·91]; difference in least square means 1·17% [95% CI 0·80 to 1·54; p<0·0001]) and at spine (mean change 1·74% [3·46] vs -0·11% [3·13]; difference in least square means 1·85% [1·24 to 2·46; p<0·0001]), creatinine clearance by Cockcroft-Gault relative to tenofovir disoproxil fumarate (median change 0·94 mL/min [IQR -4·47 to 6·24] vs -2·74 mL/min [-7·89 to 1·88]; p <0·0001), and improved markers of bone turnover and tubular function at week 48. The most common treatment-emergent adverse events were upper respiratory tract infection (18 [7%] of 243 patients in the tenofovir alafenamide group and 16 [7%] of 245 patients in the tenofovir disoproxil fumarate group) and nasopharyngitis (13 [5%] of 243 patients in the tenofovir alafenamide group and 12 [5%] of 245 patients in the tenofovir disoproxil fumarate group). The incidence of grade 3 and above adverse events and serious adverse events was low and similar between groups. No viral resistance was observed in patients who qualified for viral sequencing.

INTERPRETATION

These findings suggest that tenofovir alafenamide can be substituted for tenofovir disoproxil fumarate in patients with HBV infection for improved safety without a loss of efficacy.

FUNDING

Gilead Sciences.

Optimal management of chronic hepatitis B patients receiving nucleos(t)ide analogues

Management of chronic hepatitis B (CHB) is still considered a challenge in clinical practice. Patients must be carefully evaluated before starting therapy. This includes virology and laboratory assessments, an estimation of fibrosis by invasive and/or noninvasive methods, and an estimation of the risk of hepatocellular carcinoma (HCC). Nucleos(t)ide analogues (NAs) with a high barrier to resistance (tenofovir disoproxil fumarate [TDF], entecavir [ETV] and tenofovir alafenamide [TAF]) are the most frequently used treatments because of their good long-term efficacy and tolerability. None of these options has been shown to be more effective than the other, but certain factors should be considered when selecting the best therapy for specific populations. Most patients achieve a virological and biochemical response to these agents, with a low rate of emerging resistance during long-term treatment. However, the rate of hepatitis B surface antigen (HBsAg) loss is low and in most cases NAs therapy is lifelong. Safety concerns for long-term NA use have become a priority in the management of CHB, in particular, the risk of impaired kidney function and bone marrow density loss described with TDF regimens. The risk of HCC is not completely eliminated by NAs. Thus, patients at higher risk should be identified and provided with appropriate surveillance.

An expanded HIV care cascade: ART uptake, viral load suppression and comorbidity monitoring among adults living with HIV in Asia

BACKGROUND

Comprehensive treatment and clinical management are central to improving outcomes for people living with HIV (PLHIV). We explored trends in HIV clinical care, treatment outcomes, and chronic kidney disease (CKD) and diabetes monitoring.

METHODS

We included patients ≥18 years in care at ten clinical sites in eight Asian countries. Proportions of patients on antiretroviral therapy (ART), with annual viral load, and with viral load suppression (VLS; <1,000 copies/ml) were estimated by year for 2011-2016, stratified by country income level (lower-middle income [LMIC] and high-income countries [HIC]). Among those on ART in 2016 we evaluated factors associated with annual CKD and diabetes monitoring.

RESULTS

Among 31,346 patients (67% male), the proportions of patients on ART (median ART initiation year 2011, IQR 2007-2013), with annual viral load and VLS had substantially increased by 2016 (to 94%, 42% and 92%, respectively, in LMIC and 95%, 97% and 93%, respectively, in HIC) with the larger increases over time seen in LMIC. Among those on ART in 2016, monitoring proportions in LMIC were 53% for CKD and 26% for diabetes compared with 83% and 59%, respectively, in HIC. Overall, a decreased odds of monitoring was observed for male gender, heterosexual HIV exposure, no viral load and LMIC. Diabetes monitoring was also decreased in those with viral failure.

CONCLUSIONS

Our findings highlight suboptimal monitoring of viral load, CKD and diabetes in PLHIV in Asia. There is a need for affordable and scalable monitoring options to improve the joint care for HIV and non-communicable diseases.