Viral suppression and cirrhosis regression with tenofovir disoproxil fumarate in Asians with chronic hepatitis B

Developments in pharmacotherapeutic agents for hepatitis B - how close are we to a functional cure?

INTRODUCTION

Hepatitis B virus (HBV) remains a public health concern given its global prevalence and potential complications including hepatocellular carcinoma (HCC). Current therapies, including nucleos(t)ide analogs (NA) and interferons (IFN), are effective in chronic treatment of HBV but rarely provide a functional cure due to inadequate host response and the presence of viral DNA. Therefore, novel therapies that enhance the innate immune response while suppressing DNA transcription may provide definitive treatment of HBV.

AREAS COVERED

In this review, the authors provide a brief overview of commonly used agents and their efficacy in treatment of HBV. Newer therapies with direct antiviral agents such as bepirovirsen (antisense oligonucleotide (ASO)) and entry inhibitors such as bulevirtide have shown efficacy in reducing viral load but demonstrate further reductions in conjunction with immune modulators such as therapeutic vaccines.

EXPERT OPINION

Combination therapy is far superior to monotherapy alone, necessitating the need for both immunomodulators and direct antiviral agents in chronic treatment of HBV. Therapies that target covalently closed circular (cccDNA) with immunomodulators like therapeutic vaccines have shown promising results and may ultimately achieve functional cure. However, therapies need to be evaluated in the context of the patient, considering both financial and socioeconomic factors.

Unchanging prevalence of late presentation to care among patients with chronic hepatitis B

BACKGROUND AND STUDY AIMS

A recent consensus defines a delay in hepatitis B (HBV) diagnosis as presentation with late (hepatocellular carcinoma or decompensated cirrhosis) or advanced (fibrosis ≥ 3) stage disease. We aimed to determine the prevalence of late and advanced stage presentation among chronic HBV (CHB) patients and to determine factors associated with late and advanced stage presentation.

METHODS

Consecutive CHB patients seen from 1 January 2007 to 31 December 2018 were included and analyzed on January 2019. Time periods were divided into 2 periods (2007-2012 vs. 2013-2018). Patients were also divided into "Presentation with late stage" and "Presentation with advanced stage," and compared with "timely HBV diagnosis."

RESULTS

Out of the 782 patients, 138 (17.6%) presented with late stage while 67 (8.6%) presented with advanced stage, with no difference between the 2 time periods. Compared to patients with "timely HBV diagnosis," presentation with either late or advanced stage was more likely to be male, older, and diabetic patients, resorting to alcohol misuse and having abnormal liver chemistries (low albumin, high aspartate aminotransferase [AST], alanine aminotransferase [ALT], and international normalized ratio [INR]). Presentation with late stage liver disease was also associated with hepatitis B e antigen (HBeAg)-negative status and no family history of HBV. On multivariate analysis, male gender, older age, and alcohol misuse were associated with presentation with either late or advanced stage liver disease.

CONCLUSIONS

A quarter of CHB patients already have significant liver injury at the time of initial HBV diagnosis. The fact that presentation with late or advanced disease has not changed in 12 years emphasizes the importance of universal screening in endemic countries.

Features of fibrosis regression abound in “non-cirrhotic” patients with resected hepatocellular carcinoma

Cirrhosis is a major risk factor for developing hepatocellular carcinoma (HCC). However, many surgically resected HCCs are presumably non-cirrhotic. The dynamic nature of chronic liver disease leads to periods of hepatic repair and fibrosis regression. We hypothesize that most resected HCCs, including those from non-cirrhotic patients, exhibit features of fibrosis regression in their background liver, suggesting previously more advanced liver disease. We reviewed the histology of 37 HCC resections performed between 2005–2020, including 30 from non-cirrhotic patients. The non-neoplastic liver was evaluated for features of liver disease and of the hepatic repair complex (HRC). CD34 immunohistochemistry was performed as a marker of sinusoidal capillarization. CD34 staining was evaluated manually and also by a digital image classifier algorithm. Overall, 28 cases (76%) had a high number of fibrosis regression and hepatic repair features (≥4 out of 8 features). Amongst the 30 non-cirrhotic patients, 21 (70%) showed a high number of repair features. Relative CD34 expression was increased in cases with a high number (≥4) of HRC features versus a low number (≤3) of features (p = 0.019). High HRC cases were more likely to exhibit nodular circumferential CD34 staining (p = 0.019). Our findings suggest that most resected HCC from non-cirrhotic patients display features of fibrosis regression in their background liver. Thus many, if not most, HCC patients who are “non-cirrhotic” may in fact have regressed cirrhosis. This finding reinforces that patients with regressed cirrhosis continue to be at high risk for HCC.

Tenofovir disoproxil fumarate in Chinese chronic hepatitis B patients: Results of a multicenter, double-blind, double-dummy, clinical trial at 96 weeks

BACKGROUND

Tenofovir disoproxil fumarate (TDF) is a prodrug of a nucleotide analogue. As an antiviral drug, TDF has been proposed in the first-line treatment of chronic hepatitis B (CHB). Qingzhong, a brand name of TDF, commercialized by Jiangsu Chia-tai Tianqing Pharmaceutical Co Ltd., and Viread, another brand name of TDF, commercialized by GlaxoSmithKline, have both been approved by the State Food and Drug Administration, China.

AIM

To investigate the efficacy and safety of the two TDF agents in the treatment of Chinese CHB patients.

METHODS

This trial was registered at ClinicalTrials.gov with the identifier number of NCT02287857. A total of 330 Chinese CHB patients, among which 232 were hepatitis B e antigen (HBeAg)-positive, were included in this 5-year-long, multicenter, double-blinded, double-dummy, randomized-controlled, non-inferiority phase III trial. The participants were initially randomized into two groups: Group A (n = 161), in which the participants received 300 mg Qingzhong once a day for 48 wk; and Group B, in which the participants received 300 mg Viread once a day for 48 wk. Starting from week 49, all the participants in Groups A and B received 300 mg Qingzhong once a day until the 96^th week. In this study, the primary endpoint was the decrease in plasma level of hepatitis B virus (HBV) DNA at the 96^th week, while the secondary endpoints were suppression of HBV replication, alanine aminotransferase (ALT) normalization, HBeAg loss, and HBeAg seroconversion rates.

RESULTS

For the participants with HBeAg-positive CHB, the decrease in mean HBV DNA level relative to the baseline value was comparable between Groups A and B (5.77 vs 5.73 log₁₀ IU/mL, P > 0.05) at the 96^th week. In addition, similar percentages of HBeAg-positive participants in the two groups exhibited undetectable levels of HBV DNA, HBeAg loss, and HBeAg seroconversion (71.05% vs 77.97%, 31.00% vs 27.27%, and 20.22% vs 15.79%, respectively, in Group A vs Group B; P > 0.05). For the participants with HBeAg-negative CHB, the decrease in mean HBV DNA level relative to the baseline value was also comparable between Groups A and B (4.46 vs 4.70 log₁₀ IU/mL, P > 0.05) at the 96^th week. In addition, similar percentages of HBeAg-negative participants in the two groups exhibited undetectable levels of HBV DNA (87.23% vs 94.12% in Group A vs Group B, respectively; P > 0.05). Finally, similar percentages of CHB patients (HBeAg-positive or HBeAg-negative) in the two groups exhibited normalization of ALT (80.14% vs 84.57% in Group A vs Group B, respectively; P > 0.05), and similar incidences of adverse events were observed (106 vs 104 in Group A vs Group B, respectively; P > 0.05).

CONCLUSION

Both Qingzhong and Viread are effective and safe in the treatment of Chinese CHB patients according to the results of our clinical trial.

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.

Consensus Guidelines: Best Practices for Detection, Assessment and Management of Suspected Acute Drug-Induced Liver Injury During Clinical Trials in Adults with Chronic Viral Hepatitis and Adults with Cirrhosis Secondary to Hepatitis B, C and Nonalcoholic Steatohepatitis

With the widespread development of new drugs to treat chronic liver diseases (CLDs), including viral hepatitis and nonalcoholic steatohepatitis (NASH), more patients are entering trials with abnormal baseline liver tests and with advanced liver injury, including cirrhosis. The current regulatory guidelines addressing the monitoring, diagnosis, and management of suspected drug-induced liver injury (DILI) during clinical trials primarily address individuals entering with normal baseline liver tests. Using the same laboratory criteria cited as signals of potential DILI in studies involving patients with no underlying liver disease and normal baseline liver tests may result in premature and unnecessary cessation of a study drug in a clinical trial population whose abnormal and fluctuating liver tests are actually due to their underlying CLD. This position paper focuses on defining best practices for the detection, monitoring, diagnosis, and management of suspected acute DILI during clinical trials in patients with CLD, including hepatitis C virus (HCV) and hepatitis B virus (HBV), both with and without cirrhosis and NASH with cirrhosis. This is one of several position papers developed by the IQ DILI Initiative, comprising members from 16 pharmaceutical companies in collaboration with DILI experts from academia and regulatory agencies. It is based on an extensive literature review and discussions between industry members and experts from outside industry to achieve consensus regarding the recommendations. Key conclusions and recommendations include (1) the importance of establishing laboratory criteria that signal potential DILI events and that fit the disease indication being studied in the clinical trial based on knowledge of the natural history of test fluctuations in that disease; (2) establishing a pretreatment value that is based on more than one screening determination, and revising that baseline during the trial if a new nadir is achieved during treatment; (3) basing rules for increased monitoring and for stopping drug for potential DILI on multiples of baseline liver test values and/or a threshold value rather than multiples of the upper limit of normal (ULN) for that test; (4) making use of more sensitive tests of liver function, including direct bilirubin (DB) or combined parameters such as aspartate transaminase:alanine transaminase (AST:ALT) ratio or model for end-stage liver disease (MELD) to signal potential DILI, especially in studies of patients with cirrhosis; and (5) being aware of potential confounders related to complications of the disease being studied that may masquerade as DILI events.

Effects of nucleo(s)tide analogs therapy on chronic hepatitis B as evaluated by hepatosplenic radionuclide angiography

OBJECTIVES

Hepatosplenic radionuclide angiography is a relatively noninvasive method for evaluating hepatic portal perfusion. We used hepatosplenic radionuclide angiography to assess the effects of nucleo(s)tide analogs therapy on patients with chronic hepatitis B (CHB).

PATIENTS AND METHODS

A retrospective analysis was performed on patients who underwent hepatosplenic radionuclide angiography from January 2012 to May 2017 at the First Affiliated Hospital, College of Medicine, Zhejiang University. The correlations between the results of routine laboratory tests and hepatic perfusion index (HPI) were evaluated. The Wilcoxon signed-rank test and one-way ANOVA of repeated measures were used to compare the HPIs of patients who received nucleo(s)tide analogs therapy.

RESULTS

There is a positive correlation between HPI and cholinesterase and serum albumin (ALB) and a negative correlation between HPI and aspartate aminotransferase-to-platelet ratio index and bilirubin (TBiL). An improvement in HPI was observed in patients with an initial HPI <61% after nucleo(s)tide analogs therapy.

CONCLUSIONS

Hepatosplenic radionuclide angiography can reflect the functional reserve of the liver and monitor liver fibrosis indirectly. It can also comprehensively assess the effects of antiviral therapy on patients with CHB, and antiviral therapy is critical for the treatment of hepatitis.

Expanding Antiviral Prophylaxis During Pregnancy to Prevent Perinatal Hepatitis B Virus Infection: A Cost-effectiveness Study

Background

Mother-to-child transmission (MTCT) cannot be completely prevented by the administration of active-passive immunoprophylaxis in pregnant women with hepatitis B virus (HBV) DNA levels <10⁶ copies/mL. This study will assess the economic outcomes of expanding antiviral prophylaxis in pregnant women with HBV DNA levels <10⁶ copies/mL.

Methods

A decision model was adopted to measure the economic outcomes of expanded antiviral prophylaxis at different cutoff values of HBV DNA in HBsAg(+) pregnant women in the context of the United States and China. The model inputs, including clinical, cost, and utility data, were extracted from published studies. Sensitivity analyses were carried out to examine the uncertainty of the model outputs. Quality-adjusted life-years (QALYs) and direct medical costs were expressed over a lifetime horizon.

Results

Compared with standard antiviral prophylaxis at HBV DNA ≥10⁶ copies/mL, expanded antiviral prophylaxis improved the health outcomes, and the incremental cost of expanded antiviral prophylaxis varied from $2063 in pregnant women with HBV DNA ≥10⁵ copies/mL to $14925 in all HBsAg(+) pregnant women per QALY gained in the United States, and from $1624 to $12348 in China. The model outcome was considerably influenced by the discount rate, key clinical parameters related to the incidence of MTCT, and efficacy of the prophylaxis strategy.

Conclusions

This study indicates that antiviral prophylaxis using tenofovir among pregnant women with HBV DNA <10⁶ copies/mL may be a cost-effective option, and the cutoff value of the HBV DNA load for antiviral prophylaxis needs to be tailored.

HBV Infection in HIV-Driven Immune Suppression

Worldwide, approximately 10% of all human immunodeficiency virus (HIV)-infected people are also chronically coinfected with hepatitis B virus (HBV). HBV infection has a poor prognosis in HIV-positive people and has been documented by an increased risk of developing chronic HBV infection (CHB), progression to liver fibrosis and end-stage liver disease (ESLD) and evolution of hepatocellular carcinoma (HCC). Furthermore, in HIV patients, HBV-resolved infection is often associated with the appearance of HBV-DNA, which configures occult HBV infection (OBI) as a condition to be explored in coinfected patients. In this narrative review we summarize the main aspects of HBV infection in HIV-positive patients, emphasizing the importance of carefully considering the coinfected patient in the context of therapeutic strategies of antiretroviral therapy.

"Let my liver rather heat with wine" - a review of hepatic fibrosis pathophysiology and emerging therapeutics

Cirrhosis is characterized by extensive hepatic fibrosis, and it is the 14th leading cause of death worldwide. Numerous contributing conditions have been implicated in its development, including infectious etiologies, medication overdose or adverse effects, ingestible toxins, autoimmunity, hemochromatosis, Wilson’s disease and primary biliary cholangitis to list a few. It is associated with portal hypertension and its stigmata (varices, ascites, hepatic encephalopathy, combined coagulopathy and thrombophilia), and it is a major risk factor for hepatocellular carcinoma. Currently, orthotopic liver transplantation has been the only curative modality to treat cirrhosis, and the scarcity of donors results in many people waiting years for a transplant. Identification of novel targets for pharmacologic therapy through elucidation of key mechanistic components to induce fibrosis reversal is the subject of intense research. Development of robust models of hepatic fibrosis to faithfully characterize the interplay between activated hepatic stellate cells (the principal fibrogenic contributor to fibrosis initiation and perpetuation), hepatocytes and extracellular matrix components has the potential to identify critical components and mechanisms that can be exploited for targeted treatment. In this review, we will highlight key cellular pathways involved in the pathophysiology of fibrosis from extracellular ligands, effectors and receptors, to nuclear receptors, epigenetic mechanisms, energy homeostasis and cytokines. Further, molecular pathways of hepatic stellate cell deactivation are discussed, including apoptosis, senescence and reversal or transdifferentiation to an inactivated state resembling quiescence. Lastly, clinical evidence of fibrosis reversal induced by biologics and small molecules is summarized, current compounds under clinical trials are described and efforts for treatment of hepatic fibrosis with mesenchymal stem cells are highlighted. An enhanced understanding of the rich tapestry of cellular processes identified in the initiation, perpetuation and resolution of hepatic fibrosis, driven principally through phenotypic switching of hepatic stellate cells, should lead to a breakthrough in potential therapeutic modalities.

A randomized, double-blind, double-dummy, controlled, multicenter study of Qingzhong (tenofovir disoproxil fumarate) versus Viread for the treatment of chronic hepatitis B: First-stage results at week 48

BACKGROUND

Tenofovir disoproxil fumarate (TDF) has been widely recommended as a first-line antiviral agent to treat chronic hepatitis B (CHB). Qingzhong and Viread, formulations of TDF commercialized by Jiangsu Chia-tai Tianqing Pharmaceutical Co Ltd and GlaxoSmithKline, respectively, have both been approved by the State Food and Drug Administration, China. This study analyzed the efficacy and safety of these 2 TDF agents in Chinese patients with CHB.

METHODS

In this multicenter, randomized, double-blind, double-dummy, noninferiority phase 3 clinical trial (ClinicalTrials.gov identifier: NCT02287857), 330 Chinese patients with CHB [hepatitis B envelope antigen-positive (HBeAg) (+): 232] were randomly assigned to receive Qingzhong (group A: 161 patients) or Viread (group B: 169 patients) 300 mg once daily for 48 weeks. Subsequently, all patients were administered Qingzhong 300 mg once daily from week 49 to week 240. The primary end point was the degree of decline of plasma hepatitis B virus (HBV) DNA levels at week 48 and the secondary endpoints were viral suppression, normalization of alanine aminotransferase (ALT) levels, hepatitis B surface antigen (HBsAg)/HBeAg loss or seroconversion, and virological breakthrough.

RESULTS

Among patients with CHB who were HBeAg (+), the mean HBV DNA titer decreased similarly between the groups at week 48. The percentages of patients who achieved undetectable HBV DNA were similar between the groups (85.11% and 82.35% in groups A and B, respectively) and similar losses of HBeAg and HBeAg seroconversion rates were achieved. Moreover, for patients with CHB who were HBeAg (-), reductions in HBV DNA were similar. Among all patients with CHB, the rates of normalization of ALT and the loss of HBsAg were similar. The overall incidence of adverse events was comparable between the groups.

CONCLUSION

In conclusion, the 48-week administration of Qingzhong showed noninferior efficacy and safety profiles compared to Viread in Chinese patients with CHB.

Longitudinal effects of Nucleos(t)ide analogue therapy in chronic hepatitis B patients and the utility of non-invasive fibrosis markers during treatment: A single-center experience for up to 17 years

BACKGROUND

Fibrosis regression has been associated with nucleoside analogue (NA) treatment in chronic hepatitis B (CHB) patients. Although non-invasive fibrosis markers have been evaluated in CHB, their utility for monitoring on-treatment histologic regression has not been evaluated.

AIMS

To characterize improvements in disease severity and the utility of non-invasive biomarkers in CHB NA treated patients.

METHODS

Histology, labs, AST-to-platelet ratio index, and Fibrosis-4 (Fib-4) from treatment-naïve CHB patients were evaluated at baseline and longitudinally. Relative change from baseline to various time points during treatment were evaluated. Correlative analysis of APRI and Fib-4 with histology was performed longitudinally.

RESULTS

80 CHB patients (84% male, median age 45 (IQR 32, 54)) with histology up to 17 years (median 6(IQR 3.9, 8.0)) years were studied. Median baseline Ishak fibrosis was 3 (IQR 2, 4), histologic activity index (HAI) inflammation was 9 (IQR 7, 11), and AUROC of fibrosis markers for detecting cirrhosis (Ishak ≥ 5) was >0.64. HAI improved at a rate of 54% during year 1 and 37% in year 2, both greater than in the remaining follow-up periods. Within the first year, fibrosis improved by 35%, greater than all other time periods. Non-invasive biomarkers began to correlate with histology beyond 4 years (APRI: 4-6 years: r = 0.33, p = 0.03; ≥6 years: r = 0.41, p = 0.009; Fib-4: ≥6 years: r = 0.35, p = 0.03).

CONCLUSION

Early dynamic changes in histology occur in CHB patients on NA followed by linear improvements. Non-invasive fibrosis biomarkers do not capture these dynamic changes and may demonstrate clinical utility beyond 4 years of treatment.

Antiviral Efficacy of Tenofovir Monotherapy in Children with Nucleos(t)ide-naive Chronic Hepatitis B

BACKGROUND

The purpose was to compare the efficacy between tenofovir disoproxil fumarate (TDF) and lamivudine (LMV) in children with nucleos(t)ide-naive chronic hepatitis B (CHB) infection. Patients with CHB were treated with TDF in the immune-reactive phase and compared with a historical control group of patients treated with LMV before the TDF era.

METHODS

Hepatitis B virus (HBV) DNA titer decrements (> 3 log₁₀ IU/mL) were monitored after treatment initiation. The treatment duration for HBV DNA clearance (< 357 IU/mL) and complete response (HBeAg loss and HBV DNA clearance) were analyzed. The follow-up period was 96 weeks.

RESULTS

Sixteen patients were treated with TDF and compared with a historical control group of 24 patients treated with LMV. HBV DNA decrement (> 3 log₁₀ IU/mL) was achieved in 100% (16/16) of the TDF group but in only 62.5% (15/24) of the LMV group (P = 0.005) at 48 weeks. The HBV DNA clearance (< 357 IU/mL) in the TDF and LMV groups was, respectively, as follows: 62.5% (10/16) and 25.0% (6/24) at 12 weeks (P = 0.018), 81.3% (13/16) and 37.5% (9/24) at 24 weeks (P = 0.006), 93.8% (15/16) and 50.0% (12/24) at 48 weeks (P = 0.004), and 100% (16/16) and 54.2% (13/24) at 96 weeks (P = 0.001). Complete response occurred in 41.7% (5/12) of HBeAg-positive patients in the TDF group and 28.6% (6/21) of the LMV group at 96 weeks (P = 0.443).

CONCLUSION

TDF monotherapy for 96 weeks produced a significantly more effective virologic response than LMV monotherapy in children with nucleos(t)ide-naive CHB.

Treatment of chronic hepatitis B with tenofovir

Tenofovir (TDF) is a potent hepatitis B virus (HBV) inhibitor with a high barrier to drug resistance, and it has been recommended as one of the first-line drugs to treat chronic hepatitis B (CHB). This paper reviews the recent advances in the treatment of CHB with TDF, especially in terms of its efficacy as first-line and second-line antiviral therapies as well as its role in the prevention of mother-to-child HBV transmission.

Three-year efficacy and safety of tenofovir in nucleos(t)ide analog-naïve and nucleos(t)ide analog-experienced chronic hepatitis B patients

BACKGROUND AND AIMS

This study compared the efficacy and safety of tenofovir disoproxil fumarate (TDF) up to 3 years of innucleos(t)ide analog (NA)-naïve and NA-experienced chronic hepatitis B (CHB) patients.

METHODS

Tenofovir disoproxil fumarate-treated NA-naïve and NA-experienced CHB patients were retrospectively analyzed.

RESULTS

After 3 years of TDF therapy, 97.7%, 71%, and 45.5% NA-naïve patients achieved a virological response, alanine aminotransferase normalization, and hepatitis B e antigen seroconversion, respectively. Compared with NA-naïve patients, NA-experienced patients without drug resistance and infected with lamivudine/telbivudine-resistant mutants showed similar results. In contrast, patients previously infected with adefovir-resistant mutants and with a suboptimal entecavir response showed significantly lower rates of virological response and hepatitis B e antigen loss/seroconverion than NA-naïve patients. Mean estimated glomerular filtration rate markedly reduced within 12 months of TDF therapy; however, it did not decrease significantly during 12-36 months of treatment. Diabetes mellitus was an independent predictor of a ≥ 0.5 mg/dL increase above baseline in serum creatinine level, and age, hypertension, diabetes mellitus, and baseline creatinine level were independent factors for > 20% decline in estimated glomerular filtration rate from baseline. Liver stiffness measurements improved significantly, but bone mineral density did not change significantly during treatment. Hepatocellular carcinoma incidence was low at 36 months. Age of > 60 years, cirrhosis, a low baseline platelet count and a high α-fetoprotein level at 12 months were significant predictors of hepatocellular carcinoma development.

CONCLUSIONS

Tenofovir disoproxil fumarate is effective and safe for NA-naïve and NA-experienced CHB patients and should be used cautiously in patients with comorbidities because of a renal dysfunction risk.

Experimental models of hepatitis B and C - new insights and progress

Viral hepatitis is a major cause of morbidity and mortality, affecting hundreds of millions of people worldwide. Hepatitis-causing viruses initiate disease by establishing both acute and chronic infections, and several of these viruses are specifically associated with the development of hepatocellular carcinoma. Consequently, intense research efforts have been focusing on increasing our understanding of hepatitis virus biology and on improving antiviral therapy and vaccination strategies. Although valuable information on viral hepatitis emerged from careful epidemiological studies on sporadic outbreaks in humans, experimental models using cell culture, rodent and non-human primates were essential in advancing the field. Through the use of these experimental models, improvement in both the treatment and prevention of viral hepatitis has progressed rapidly; however, agents of viral hepatitis are still among the most common pathogens infecting humans. In this Review, we describe the important part that these experimental models have played in the study of viral hepatitis and led to monumental advances in our understanding and treatment of these pathogens. Ongoing developments in experimental models are also described.

Cost-effectiveness of active-passive prophylaxis and antiviral prophylaxis during pregnancy to prevent perinatal hepatitis B virus infection

In an era of antiviral treatment, reexamination of the cost-effectiveness of strategies to prevent perinatal hepatitis B virus (HBV) transmission in the United States is needed. We used a decision tree and Markov model to estimate the cost-effectiveness of the current U.S. strategy and two alternatives: (1) Universal hepatitis B vaccination (HepB) strategy: No pregnant women are screened for hepatitis B surface antigen (HBsAg). All infants receive HepB before hospital discharge; no infants receive hepatitis B immunoglobulin (HBIG). (2) Current strategy: All pregnant women are screened for HBsAg. Infants of HBsAg-positive women receive HepB and HBIG ≤12 hours of birth. All other infants receive HepB before hospital discharge. (3) Antiviral prophylaxis strategy: All pregnant women are screened for HBsAg. HBsAg-positive women have HBV-DNA load measured. Antiviral prophylaxis is offered for 4 months starting in the third trimester to women with DNA load ≥10(6) copies/mL. HepB and HBIG are administered at birth to infants of HBsAg-positive women, and HepB is administered before hospital discharge to infants of HBsAg-negative women. Effects were measured in quality-adjusted life years (QALYs) and incremental cost-effectiveness ratios (ICER). Compared to the universal HepB strategy, the current strategy prevented 1,006 chronic HBV infections and saved 13,600 QALYs (ICER: $6,957/QALY saved). Antiviral prophylaxis dominated the current strategy, preventing an additional 489 chronic infections, and saving 800 QALYs and $2.8 million. The results remained robust over a wide range of assumptions.

CONCLUSION

The current U.S. strategy for preventing perinatal HBV remains cost-effective compared to the universal HepB strategy. An antiviral prophylaxis strategy was cost saving compared to the current strategy and should be considered to continue to decrease the burden of perinatal hepatitis B in the United States.

Regression of esophageal varices during entecavir treatment in patients with hepatitis-B-virus-related liver cirrhosis

Recent studies suggest that liver cirrhosis is reversible after administering oral nucleos(t)ide analogue therapy to patients with hepatitis B virus (HBV) infection. However, few studies have addressed whether esophageal varices can regress after such therapy. We report a case of complete regression of esophageal varices during entecavir therapy in patients with HBV-related liver cirrhosis, suggesting that complications of liver cirrhosis such as esophageal varices can regress after the long-term suppression of HBV replication.

Recent Advances in the Management of Chronic Hepatitis B Including Suppression of Hepatocellular Carcinoma by Entecavir and Interferon

At present, for adults with chronic hepatitis B virus (HBV) infection, two new analogues, entecavir (ETV) and tenofovir, are recommended as the first-line therapy by the EASL (European Association for the Study of the Liver), AASLD (American Association for the Study of Liver Diseases), and APASL (Asian Pacific Association for the Study of the Liver) guidelines. The use of pegylated interferon-α (PEG IFN-α) is recommended as the first-line therapy instead of standard IFN-α according to the above 3 guidelines. In this paper, the aim was to assess: (1) the long-term efficacy and safety as well as the resistance to ETV and tenofovir disoproxil fumarate (TDF); (2) the efficacy of PEG IFN-α; (3) the role of combination therapy with IFN plus two analogues, such as lamivudine and ETV; (4) the efficacy and safety of two analogues with cirrhosis, and (5) suppression of hepatocellular carcinoma (HCC) by ETV and IFN treatment. The results are as follows: (1) both ETV and TDF showed long-term efficacy and safety; (2) PEG IFN-α resulted in a greater decline in HBV DNA levels and a higher rate of HBeAg seroconversion; (3) combination therapy with IFN plus two analogues did not elevate the rate of sustained responses; (4) both ETV and TDF showed efficacy and safety with cirrhosis (ETV especially displayed efficacy and safety with decompensated cirrhosis), and (5) suppression of HCC was observed by ETV and IFN.

Long-term safety of oral nucleos(t)ide analogs for patients with chronic hepatitis B: A cohort study of 53,500 subjects

Widespread and long-term use of oral nucleos(t)ide analogs (NAs) to treat chronic hepatitis B (CHB) brings about safety data in a real-life setting. We aimed to determine the risks of renal and bone side effects in patients receiving or who have received NAs as CHB treatment. A territory-wide cohort study using the database from Hospital Authority, the major provider of medical services in Hong Kong, was conducted. We identified CHB patients by International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes, diagnosed between 2000 and 2012. The primary events were renal (incident renal failure and renal replacement therapy [RRT]) and bone events (incident hip, vertebral, and all fractures). A 3-year landmark analysis was used to evaluate the relative risk of primary outcome in patients with or without NA treatment. A total of 53,500 CHB patients (46,454 untreated and 7,046 treated), who were event free for 3 years, were included in the analysis. At a median follow-up of 4.9 years, chronic renal failure, RRT, all fractures, hip fractures, and vertebral fractures occurred in 0.6%, 0.2%, 0.7%, 0.1%, and 0.1% of untreated subjects and 1.4%, 0.7%, 1.3%, 0.2%, and 0.2% of treated subjects. After propensity score weighting, NA therapy did not increase the risk of any of the events (hazard ratios [HRs] ranged from 0.79 to 1.31; P = 0.225-0.887). Exposure to nucleotide analogues, compared with nucleoside analogs, increased the risk of hip fracture (HR = 5.69; 95% confidence interval: 1.98-16.39; P = 0.001), but not other events (HR = 0.58-1.44; P = 0.202-0.823).

CONCLUSIONS

NA treatment does not increase the risk of renal and bone events in general. Nucleotide analogs may increase the risk of hip fracture, but the overall event rate is low.

Antiviral Therapy in Hepatitis B Virus-Associated Liver Cirrhosis

BACKGROUND

Chronic hepatitis B virus (HBV) infection is a major risk factor for the development of liver cirrhosis and hepatocellular carcinoma (HCC). Key Messages: In patients with advanced liver fibrosis or liver cirrhosis, antiviral therapy is mandatory to slow down, halt or reverse disease progression and possibly reduce the risk of HCC development. As in patients without advanced fibrosis, PEG-interferon and nucleoside/nucleotide analogues (NUCs) are available for antiviral therapy. NUC therapy should be performed indefinitely as the rates of HBs-Ag loss are low. Entecavir or tenofovir should be preferred due to their strong antiviral potency and their high barrier to resistance. PEG-interferon therapy can be administered to patients with compensated liver disease but should not be offered to patients with signs of hepatic decompensation.

CONCLUSIONS

Antiviral therapy in chronic HBV infection can reduce liver fibrosis and even revert overt cirrhosis. Whether it also reduces the risk of HCC development in cirrhotic patients remains elusive and might vary in different countries and ethnicities.