Long-term Efficacy of Tenofovir Disoproxil Fumarate Monotherapy for Multidrug-Resistant Chronic HBV infection

Effectiveness and safety of tenofovir amibufenamide and tenofovir alafenamide in treating elderly patients diagnosed with decompensated hepatitis B cirrhosis: a retrospective cohort study

Background/aim

Tenofovir amibufenamide (TMF) has demonstrated significant antiviral activity and safety in individuals with chronic hepatitis B (CHB) in randomized clinical trials. The purpose of this study was to investigate the effectiveness and safety disparities between TMF and Tenofovir alafenamide (TAF) in treating elderly patients with decompensated hepatitis B cirrhosis in real-world settings.

Methods

A retrospective cohort analysis of elderly patients with decompensated hepatitis B cirrhosis who were treated with TMF or TAF in our hospital's outpatient department between January 2022 and December 2023 was the focus of this study. Following a 24-week treatment period, this study evaluated the disparities between the TMF and TAF groups in terms of primary efficacy endpoints (virologic response rate, VR rate), secondary efficacy endpoints (normalization rate of ALT, HBsAg and HBeAg clearance rate, HBsAg and HBeAg seroconversion rates), as well as safety endpoints related to renal function and blood lipids.

Results

The study included 171 patients (93 in the experimental group and 78 in the control group). Following a 24-week treatment period, HBV DNA, HBsAg, ALT, AST, and TBIL had significantly decreased compared to the baseline level, and the differences were statistically difference. Cr, eGFR, triglyceride, and TG had no significant changes compared with the baseline level, and the differences were no statistical difference. The virologic response rate in the experimental group was 70.97% (33/93), and that in the control group was 73.08% (57/78), with no statistical difference observed between the two groups (P = 0.760). ALT normalization rate was 83.33% in the experimental group and that was 100% in the control group, and there was not a statistically significant distinction between the two groups (P = 0.229). Compared with baseline data, Cr and eGFR of the experimental group increased (2.97 ± 14.66 μmol/L, P = 0.867; 0.29 ± 6.76 mL/min/1.72 m2, P = 0.680), TC and TG decreased (-0.5 ± 1.30 mmol/L, P = 0.589; -0.006 ± 0.23 mmol/L, P = 0.986), however, no statistical difference was observed. Compared with the control group, the change of safety dates was also no statistical difference.

Conclusion

TMF treatment in elderly patients with decompensated hepatitis B cirrhosis had a good antiviral effect, no adverse drug reaction on renal function and blood lipids, and high safety. TMF is not inferior to TAF in antiviral efficacy and safety.

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.

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.

Switching from Tenofovir-Based Combination Therapy to Tenofovir Monotherapy in Multidrug-Experienced Chronic Hepatitis B Patients: a 5-Year Experience at Two Centers

Patients with chronic hepatitis B (CHB) who were administered tenofovir disoproxil fumarate (TDF)-based combination therapy after receiving multiple drugs are frequently switched to TDF monotherapy in South Korea. We evaluated the efficacy and safety of switching to TDF monotherapy from TDF-based combination therapy over 5 years. This was a retrospective study of multidrug-experienced CHB patients who switched from TDF-based combination therapy to TDF monotherapy after achieving a virologic response (VR; <20 IU/mL) at Konkuk University Hospital and Sanggye Paik Hospital. The biochemical response was defined as a normalized serum ALT level during follow-up. Each patient was assessed from the date of switching to TDF monotherapy to the date of the last follow-up over 5 years. A total of 39 patients who received at least one antiviral therapy before TDF-based combination therapy were analyzed. The median duration of VR before switching to TDF monotherapy was 18 months and the median duration of TDF monotherapy was 55 months. In this study, except for one patient who had poor compliance, all patients maintained a VR. Three patients had a temporarily increased HBV DNA level and 91.2% of the patients showed a biochemical response. Switching multidrug-experienced patients to TDF monotherapy is generally safe and effective.

Treatment of Chronic Hepatitis B Virus with Oral Anti-Viral Therapy

Nucleoside analogues are the drugs most commonly used in the treatment of chronic hepatitis B. They act by inhibiting viral replication and have minimal impact on HBsAg loss. Nucleoside analogues are indicated in patients with chronic hepatitis, cirrhosis, decompensated cirrhosis, hepatocellular carcinoma, and in those with extrahepatic manifestations. Real-world experience has been ongoing for more than 10 years, and the efficacy and safety results obtained are similar to those reported in clinical trials. Prolonged use is needed to maintain suppression of viral replication, prevent the development of liver cirrhosis and decompensated cirrhosis, and to decrease the risk of hepatocellular carcinoma.

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.

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.

A systematic review of the quality of reporting of interventions in the surgical treatment of Crohn's anal fistula: an assessment using the TIDiER and Blencowe frameworks

BACKGROUND

Crohn's anal fistula is a challenging condition, and may require multiple surgical procedures. To replicate successful procedures, these must be adequately reported in the literature. The aim of this study was to review the quality of reporting of components of surgical interventions for Crohn's anal fistula.

METHODS

A systematic review was conducted. It was registered with PROSPERO (CRD:42019135157). The Medline and EMBASE databases were searched for studies reporting interventions intended to close fistula in patients with Crohn's disease, published between 1999 and August 2019. Abstracts and full texts were screened for inclusion by two reviewers. Dual extraction of data was performed to compare reporting to the TIDiER and Blencowe frameworks for reporting of interventions.

RESULTS

Initial searches identified 207 unique studies; 38 full texts were screened for inclusion and 33 were included. The most common study design was retrospective cohort (17/33), and the most frequently reported interventions were anal fistula plug (n = 8) and fibrin glue (n = 6). No studies showed coverage of all domains of TIDieR. Reporting was poor among domains related to who provided an intervention, where it was provided, and how it was tailored. Reporting of domains in the Blencowe framework was poor; the majority of studies did not report the component steps of procedures or efforts to standardise them.

CONCLUSIONS

This study demonstrates that reporting on technical aspects of interventions for Crohn's anal fistula is poor. Surgeons should aim to improve reporting to allow accurate reproduction of techniques both in clinical practice and in clinical trials.

Investigation of multidrug-resistance mutations of hepatitis B virus (HBV) in a large cohort of chronic HBV-infected patients with treatment of nucleoside/nucleotide analogs

Multidrug-resistance hepatitis B virus (MDR HBV), defined as those with mutations resistant to both nucleoside analogs lamivudine/telbivudine/entecavir (LAM/LdT/ETV) and nucleotide analog adefovir (ADV), has potential to cause treatment difficulty. To clarify clinical prevalence and virological features of MDR HBV, we investigated serum samples from 28,236 chronic HBV-infected patients with treatment of nucleoside/nucleotide analogs. All patients underwent resistance testing in the Fifth Medical Center of Chinese PLA General Hospital between 2007 and 2019. MDR mutations were screened by direct sequencing; MDR strains (with mutations co-located on the same viral genome) were verified by clonal sequencing (≥20 clones/sample) and subjected to phenotypic analysis if necessary. MDR mutations were detected in 0.81% (229/28,236) patients. MDR strains were verified in 83.0% (190/229) of MDR mutation-positive patients. As ETV-resistance mutation (ETVr) had additional mutation(s) on LAMr conferring more resistance, MDR mutations fell into LAMr + ADVr and ETVr + ADVr subsets. Sixteen mutation patterns of MDR strains were verified, including eight with LAMr + ADVr and eight with ETVr + ADVr. Refractory to sequential therapies of LAM/LdT/ETV and ADV were closely linked with MDR HBV development. Ten representative MDR strains (five LAMr + ADVr and five ETVr + ADVr) tested all had decrease in replication capacity compared to wild-type strains and decrease extent was positively related with the number of primary resistance on viral genome. Compared to ADV + ETV, TDF/TDF + ETV showed higher inhibitory rates on MDR HBV, especially for the five ETVr + ADVr strains (74.5%-97.6% vs. 60.2%-79.5%, all P < 0.05). This study significantly extends the knowledge on MDR HBV and has clinical implications for resistance management.

An expert review on the use of tenofovir alafenamide for the treatment of chronic hepatitis B virus infection in Asia

Asia has intermediate-to-high prevalence and high morbidity of hepatitis B virus (HBV) infection. The use of guideline-recommended nucleos(t)ide analogs with high barrier to resistance, such as entecavir (ETV), tenofovir disoproxil fumarate (TDF), and tenofovir alafenamide (TAF), is one of the key interventions for curbing HBV infection and associated morbidity in Asia. However, there are some challenges to the use of ETV and TDF; while ETV is associated with high resistance in lamivudine (LAM)-exposed (especially LAM-refractory) patients; bone and renal safety issues are a major concern with TDF. Hence, a panel of twenty-eight expert hepatologists from Asia convened, reviewed the literature, and developed the current expert opinion-based review article for the use of TAF in the resource-constrained settings in Asia. This article provides a comprehensive review of two large, phase 3, double-blind, randomized controlled trials of TAF versus TDF in HBeAg-negative (study 0108) and HBeAg-positive (study 0110) chronic HBV patients (> 70% Asians). These studies revealed as follows: (1) non-inferiority for the proportion of patients who had HBV DNA < 29 IU/mL; (2) significantly high rate of normalization of alanine aminotransferase levels; (3) no incidence of resistance; and (4) significantly better bone and renal safety, with TAF vs. TDF up to 144 weeks. Considering the benefits of TAF, the expert panel proposed recommendations for optimizing the use of TAF in Asia, along with guidance on specific patient groups at risk of renal or bone disease suitable for TAF therapy. The guidance provided in this article may help clinicians optimize the use of TAF in Asia.

Comparison of clinical practice guidelines for the management of chronic hepatitis B: When to start, when to change, and when to stop

Clinical practice guidelines are important for guiding the management of specific diseases by medical practitioners, trainees, and nurses. In some cases, the guidelines are utilized as a reference for health policymakers in controlling diseases with a large public impact. With this in mind, practice guidelines for the management of chronic hepatitis B (CHB) have been developed in the United States, Europe, and Asian-Pacific regions to suggest the best-fit recommendations for each social and medical circumstance. Recently, the Korean Association for the Study of the Liver published a revised version of its clinical practice guidelines for the management of CHB. The guidelines included updated information based on newly available antiviral agents, the most recent opinion on the initiation and cessation of treatment, and updates for the management of drug resistance, partial virological response, and side effects. Additionally, CHB management in specific situations was comprehensively revised. This review compares the similarities and differences among the various practice guidelines to identify unmet needs and improve future recommendations.

An observational study on long-term renal outcome in patients with chronic hepatitis B treated with tenofovir disoproxil fumarate

In patients with chronic hepatitis B (CHB), long-term effects of tenofovir disoproxil fumarate (TDF) on renal function have been controversial. This study aimed to analyse the real-world long-term effects of TDF on renal function in Korean patients with CHB. We analysed a cohort of 640 treatment-naïve patients with CHB who were treated with TDF between May 2012 and December 2015 at Severance Hospital, Seoul, Republic of Korea. The mean age was 48.3 years old, and 59.5% were male. The proportions of hypertension and diabetes mellitus (DM) were 11.6% and 14.2%, respectively, and that of liver cirrhosis was 20.8%. During the 5-year follow-up, using a linear mixed model, serum creatinine increased from 0.77 ± 0.01 mg/dL to 0.85 ± 0.02 mg/dL (P < .001), and eGFR decreased from 102.6 ± 0.6 mL/min/1.73 m2 to 93.4 ± 1.4 mL/min/1.73 m2 (P < .001). In subgroup analysis, eGFR was statistically more decreased in patients with age > 60 than ≦60 years old (P = .027), and in patients with diuretic use than without diuretic use (P = .008). In multivariate analysis, the independent risk factors for eGFR decrease > 20% were baseline eGFR < 60mL/min/1.73 m2 (P = .034) and the use of diuretics (P < .001). CHB patients on TDF experienced greater reduction in renal function with age > 60 and with diuretic use compared to those without these characteristics. Baseline eGFR < 60 mL/min/1.73 m2 and use of diuretics were independent risk factors of eGFR decline of more than 20% on TDF therapy.

Hepatitis B surface antigen reduction as a result of switching from long-term entecavir administration to tenofovir

Background and Aim

Loss of hepatitis B surface antigen (HBsAg) is an important goal in the treatment of chronic hepatitis B. We investigated whether switching from long‐term entecavir (ETV) administration to tenofovir (TFV) (tenofovir alafenamide [TAF] or tenofovir disoproxil fumarate [TDF]) could contribute to the reduction of HBsAg levels.

Methods

The degree of HBsAg reduction by 48 weeks in 30 patients following switching from ETV to TFV was compared with results from 147 patients who continued ETV as a control.

Results

TFV group switched to TFV after mean 6.79 years of ETV administration. HBV‐DNA levels remained below 1.0 log IU/mL in all cases in both groups during 48 weeks. Median HBsAg reduction at 48 weeks was 0.075 (−0.05 to 0.38) log/IU/mL in the TFV switch group, and 0.070 (−0.28 to 0.50) in the ETV continuation group, which was not statistically significant (p = 0.5). In a subgroup of hepatitis B e antigen negative patients whose HBsAg had not been reduced (HBsAg reduction ≤0 log IU/mL) in the 48 weeks prior to entry into the study, HBsAg reduction was significantly higher in the TFV switch group than in the ETV continuation group (0.15 [0.07–0.135] in TFV, 0.09 [−0.14 to 0.25] log IU/mL in ETV, p = 0.04).

Conclusion

Although HBsAg reduction is equivalent with ETV continuation and switching to TFV in all patients at 48 weeks, switching from ETV to TFV could provide an alternative therapeutic strategy toward HBsAg elimination in a specific subpopulation of patients.