Sustained HBeAg and HBsAg loss after long-term follow-up of HBeAg-positive patients treated with peginterferon alpha-2b

HBsAg seroclearance or seroconversion induced by peg-interferon alpha and lamivudine or adefovir combination therapy in chronic hepatitis B treatment: a meta-analysis and systematic review

BACKGROUND AND AIMS

Seroclearance or seroconversion of hepatitis B surface antigen (HBsAg) is generally considered as the clinical endpoint. The purpose of the present meta-analysis was to evaluate pegylated interferon alpha (PEG-IFNα) with or without lamivudine (LAM) or adefovir (ADV) combination treatment in HBsAg seroclearance or seroconversion with CHB.

METHODS

Randomized controlled trials of adults with CHB prior to May 30th 2015, with 48-52 weeks of PEG-IFNα and LAM or ADV combination therapy or monotherapy, were included. Review Manager Software 5.2.0 was used for meta-analysis.

RESULTS

No statistical difference was noticed in HBsAg seroclearance (9.9% vs 7.1%, OR = 1.47, 95% CI 0.75, 2.90; p = 0.26) or observed in HBsAg seroconversion (4.2% vs 3.7%, OR = 1.17, 95% CI 0.57, 2.37; p = 0.67) between PEG-IFNα + LAM and PEG-IFNα + placebo for 24-26 weeks follow-up after treatment on hepatitis B e antigen (HBeAg)-positive CHB. Statistical difference was not showed in HBsAg disappearance (10.5% vs 6.4%, OR = 1.68, 95% CI 0.75, 3.76; p = 0.21) but was demonstrated in HBsAg seroconversion (6.3% vs 0%, OR = 7.22, 95% CI 1.23, 42.40; p = 0.03) between PEG-IFNα + ADV and PEG-IFNα for 48-52 weeks treatment on HBeAg-positive CHB By systematical evaluation, there were no differences in HBsAg disappearance and seroconversion between PEG-IFNα + placebo and PEG-IFNα + LAM for 48-52 weeks treatment on HBeAg-positive CHB. There were no differences in HBsAg disappearance and seroconversion between PEG-IFNα + placebo and PEG-IFNα + LAM during 24 weeks to 3 years follow-up after treatment on HBeAg-negative CHB by systematical evaluation.

CONCLUSION

The combination between PEG-IFNα and LAM or ADV was not superior to monotherapy of PEG-IFNα in terms of HBsAg seroclearance or seroconversion.

Kinetics of Hepatitis B Surface Antigen Level in Chronic Hepatitis B Patients who Achieved Hepatitis B Surface Antigen Loss during Pegylated Interferon Alpha-2a Treatment

Background:

Hepatitis B surface antigen (HBsAg) loss/seroconversion is considered to be the ideal endpoint of antiviral therapy and the ultimate treatment goal in chronic hepatitis B (CHB). This study aimed to assess the patterns of HBsAg kinetics in CHB patients who achieved HBsAg loss during the treatment of pegylated interferon (PEG-IFN) α-2a.

Methods:

A total of 150 patients were enrolled, composing of 83 hepatitis B envelope antigen (HBeAg)-positive and 67 HBeAg-negative patients. Patients were treated with PEG-IFN α-2a180 μg/week until HBsAg loss/seroconversion was achieved, which occurred within 96 weeks. Serum hepatitis B virus deoxyribonucleic acid and serological indicators (HBsAg, anti-HBs, HBeAg, and anti-HBe) were determined before and every 3 months during PEG-IFN α-2a treatment. Biochemical markers and peripheral blood neutrophil and platelet counts were tested every 1–3 months.

Results:

Baseline HBsAg levels were 2.5 ± 1.3 log IU/ml, and decreased rapidly at 12 and 24 weeks by 48.3% and 88.3%, respectively. The mean time to HBsAg loss was 54.2 ± 30.4 weeks, though most patients needed extended treatment and 30.0% of HBsAg loss occurred during 72–96 weeks. Baseline HBsAg levels were significantly higher in HBeAg-positive patients (2.9 ± 1.1 log IU/ml) compared with HBeAg-negative patients (2.0 ± 1.3 log IU/ml; t = 4.733, P < 0.001), but the HBsAg kinetics were similar. Patients who achieved HBsAg loss within 48 weeks had significantly lower baseline HBsAg levels and had more rapid decline of HBsAg at 12 weeks compared to patients who needed extended treatment to achieve HBsAg loss.

Conclusions:

Patients with lower baseline HBsAg levels and more rapid decline during early treatment with PEG-IFN are more likely to achieve HBsAg loss during 96 weeks of treatment, and extended therapy longer than 48 weeks may be required to achieve HBsAg loss.

Genetic variation in the vitamin D pathway CYP2R1 gene predicts sustained HBeAg seroconversion in chronic hepatitis B patients treated with pegylated interferon: A multicenter study

Evidence of a role of vitamin D in the immune system is increasing. Low serum vitamin D is associated with increased hepatitis B virus replication. Genome-wide association study (GWAS) data has revealed a number of the single nucleotide polymorphisms (SNPs) within the vitamin D synthetic pathway that affect vitamin D functions. We aimed to determine the association between SNPs in the vitamin D gene cascade and response to pegylated interferon (PegIFN) therapy in hepatitis B e-antigen (HBeAg)-positive patients. One hundred and eleven patients treated for 48 weeks with PegIFN-alfa 2a at 13 hospitals were retrospectively evaluated. Thirteen SNPs derived from vitamin D cascade-related genes, including DHCR7 (rs12785878), CYP27B1 (rs10877012), CYP2R1 (rs2060793, rs12794714), GC (rs4588, rs7041, rs222020, rs2282679), and VDR (FokI, BsmI, Tru9I, ApaI, TaqI), were genotyped. Thirty-one patients (27.9%) seroconverted to HBeAg after 24 weeks of treatment. Multivariate analysis found pretreatment qHBsAg <10,000 IU/mL (OR = 7.73, 95% CI: 2.36-25.31, P = 0.001), CYP2R1 rs12794714 TT genotype (OR = 4.16, 95% CI: 1.07-16.25, P = 0.04), and baseline ALT >2 times the upper limit of normal (OR = 3.83, 95% CI: 1.31-11.22, P = 0.014) predicted sustained HBeAg seroconversion after completion of PegIFN treatment. HBV DNA during study period tended to be lower with the rs12794714 CYP2R1 TT than the non-TT genotype. The rs12794714 CYP2R1 polymorphism may be a useful pretreatment factor predictive of sustained HBeAg seroconversion after PegIFN therapy. This study provides evidence that not only vitamin D level but also genetic variation of CYP2R1 in the vitamin D cascade influences host immune response in chronic HBV infection.

Efficacy and safety of entecavir versus tenofovir treatment in chronic hepatitis B patients: A randomized controlled trial

AIM

Entecavir (ETV) and tenofovir disoproxil fumarate (TDF) are considered among the most potent antiviral agents for the treatment of chronic hepatitis B infection. We aimed to compare treatment efficacy and safety of ETV and TDF in nucleoside-naïve chronic hepatitis B patients.

METHODS

Inclusion criteria were compensated chronic hepatitis B patients who were either hepatitis B e antigen (HBeAg)-positive or HBeAg-negative. Exclusion criteria were co-infection with hepatitis C virus and/or HIV, concurrent malignancy, and decompensated cirrhosis. Virological, biochemical, and serological end-points at week 96 and 144 were compared. Of 400 patients, 200 patients received ETV and 200 received TDF.

RESULTS

There were no significant differences between the two groups in baseline characteristics including age (41.6 ± 11.5 vs. 41.2 ± 11.6, mean baseline hepatitis B virus DNA (5.91 ± 1.79 vs. 5.94 ± 1.68 log₁₀ IU/mL), mean baseline alanine aminotransferase (68.1 ± 64.1 vs. 76.8 ± 79.8 U/L), and cirrhosis (15.5% vs. 14.5%). At week 144 of treatment, 91 and 94% of the ETV and TDF groups, respectively, achieved undetectable hepatitis B virus DNA. In HBeAg-positive patients, HBeAg seroconversion could be achieved in 27.4% and 33.7% at week 144 for ETV and TDF groups, respectively. Quantitative hepatitis B surface antigen dropped significantly over 144 weeks of treatment period but only 1.0 to 1.5% experienced hepatitis B surface antigen loss. Safety profiles were consistent with previous reports of monotherapy.

CONCLUSION

Both ETV and TDF showed potent antiviral activity against hepatitis B. Either ETV or TDF can be recommended as a treatment of choice for patients with chronic hepatitis B. Both drugs were safe and well tolerated.

Telbivudine versus entecavir in patients with undetectable hepatitis B virus DNA: a randomized trial

BACKGROUND

Telbivudine has been suggested to induce hepatitis B surface antigen (HBsAg) decline to the similar degree as pegylated interferon. We aimed to investigate whether telbivudine could further decrease HBsAg titer in patients who maintain undetectable serum hepatitis B virus (HBV) DNA after initial entecavir treatment.

METHODS

In this open-label trial, patients who had serum HBsAg and HBV DNA levels ≥1,000 IU/mL and <60 IU/mL, respectively, following entecavir (0.5 mg/day) treatment for HBeAg-positive chronic hepatitis B were randomized to either switch treatment to telbivudine (600 mg/day, n = 47) or continue entecavir (n = 50) for 48 weeks.

RESULTS

The baseline characteristics were comparable between groups including HBsAg levels (median, 3.41 log₁₀ IU/mL). All patients had undetectable HBV DNA and normal alanine aminotransferase level. At week 48, the mean change in serum HBsAg levels was not significantly different between the telbivudine and entecavir groups (-0.03 log₁₀ IU/mL vs. -0.05 log₁₀ IU/mL; P = 0.57). No patient experienced HBsAg seroclearance or HBsAg decline >0.5 log₁₀ IU/mL. Eleven patients (23.4%) in the telbivudine group, but none in the entecavir group, experienced virologic breakthrough (P < 0.001). Seven patients (14.9%) exhibited genotypic resistance mutations (M204I +/- L180M) during the virologic breakthrough.

CONCLUSION

Sequential therapy with entecavir followed by telbivudine resulted in a high rate of virologic breakthrough and drug-resistance without any beneficial effect on HBsAg decline. These results do not support the use of low genetic barrier drugs as a switch treatment strategy in patients who achieve virologic response with high genetic barrier drugs.

TRIAL REGISTRATION

NCT01595685 (date of trial registration: May 8, 2012).

Tenofovir alafenamide demonstrates broad cross-genotype activity against wild-type HBV clinical isolates and maintains susceptibility to drug-resistant HBV isolates in vitro

Tenofovir alafenamide (TAF) is a novel prodrug of tenofovir (TFV). This study evaluated the antiviral activity of TAF against wild-type genotype A-H HBV clinical isolates as well as adefovir-resistant, lamivudine-resistant, and entecavir-resistant HBV isolates. Full length HBV genomes or the polymerase/reverse transcriptase (pol/RT) region from treatment-naïve patients infected with HBV genotypes A-H were amplified and cloned into an expression vector under the control of a CMV promoter. In addition, 11 drug resistant HBV constructs were created by site-directed mutagenesis of a full length genotype D construct. Activity of TAF was measured by transfection of each construct into HepG2 cells and assessment of HBV DNA levels following treatment across a range of TAF concentrations. TAF activity in vitro was similar against wild-type genotype A-H HBV clinical isolates. All lamivudine- and entecavir-resistant isolates and 4/5 adefovir-resistant isolates were found to be sensitive to inhibition by TAF in vitro as compared to the wild-type isolate. The adefovir-resistant isolate rtA181V + rtN236T exhibited low-level reduced susceptibility to TAF. TAF is similarly active in vitro against wild-type genotype A-H HBV clinical isolates. The TAF sensitivity results for all drug-resistant isolates are consistent with what has been observed with the parent drug TFV. The in vitro cell-based HBV phenotyping assay results support the use of TAF in treatment of HBV infected subjects with diverse HBV genotypes, in both treatment-naive and treatment-experienced HBV infected patients.

Prediction model for sustained hepatitis B e antigen seroconversion to peginterferon alfa-2a in chronic hepatitis B

BACKGROUND AND AIM

Clinically applicable models to predict hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) response to peginterferon (PEG-IFN) are scarce. This study aimed to develop simple scoring systems, based on multiple parameters, for predicting sustained HBeAg seroconversion to PEG-IFN.

METHODS

Eighty-five treatment-naïve patients with HBeAg-positive CHB underwent 52-week PEG-IFN treatment and 24-week follow-up. Logistic regression analysis assessed parameters at baseline and weeks 12, 24, and 52 to predict HBeAg seroconversion at week 24 off-treatment. The best three predictors at each time point were included in prediction models of PEG-IFN therapy efficacy.

RESULTS

The three most meaningful predictors were alanine aminotransferase (ALT) > 5 × ULN, HBeAg ≤ 500 S/CO, and antibody to hepatitis B core antigen (anti-HBc) > 10.7 S/CO at baseline; HBeAg ≤ 20 S/CO, anti-HBc > 11.7 S/CO, and HBeAg decline > 1 log₁₀ S/CO at week 12; ALT > 2 × ULN, HBeAg ≤ 15 S/CO, and anti-HBc > 10.4 S/CO at week 24; HBeAg ≤ 5 S/CO, anti-HBc > 11.1 S/CO, and hepatitis B virus DNA decline > 2 log₁₀ copies/mL at week 52. Parameters meeting optimal cutoff thresholds were scored 1 or otherwise scored 0. For total scores of 0 versus 3 at baseline and weeks 12, 24, and 52, response rates were 6.3%, 12.5%, 0%, and 0% versus 90.0%, 83.3%, 76.9%, and 86.4%, respectively.

CONCLUSIONS

We successfully established prediction models for PEG-IFN response in HBeAg-positive CHB.

Treatment of hepatitis B virus: an update

Chronic hepatitis B virus infection is a global health concern as it affects over 240 million people worldwide and an estimated 686,000 people die annually as a result of complications of the disease. With the development of newer antiviral drugs, viral suppression of HBV is achievable, however elimination of HBV from infected individuals (functional cure) remains an issue. Due to persistence of HBV DNA (cccDNA) in infected cells, chronically infected patients who discontinue therapy prior to HBsAg loss or seroconversion are likely to relapse. Several novel therapeutic strategies are being researched and studied in clinical trials. Here we review these novel strategies to achieve sustained cure or elimination of HBV. These strategies include the targeting of the host or viral factors required for viral persistence as well as therapeutic vaccines.

Antiviral effects of anti-HBs immunoglobulin and vaccine on HBs antigen seroclearance for chronic hepatitis B infection

BACKGROUND AND AIMS

Interferon and nucleotide/nucleoside analogues are the main treatments for chronic hepatitis B. These drugs effectively reduce serum hepatitis B virus (HBV) DNA titers but fail to sufficiently reduce hepatitis B surface antigen (HBsAg) levels. Following the recent identification of sodium taurocholate cotransporting polypeptide as a receptor for HBV entry, inhibition of HBV entry has become an attractive therapeutic target for chronic hepatitis B treatment. We therefore evaluated the antiviral effects of antibody to HBsAg (anti-HBs) immunoglobulin (HBIG), which can inhibit HBV entry, by in an vivo study and a clinical trial.

METHODS

In the in vivo study, HBV-infected mice were generated from human hepatocyte chimeric mice and treated with HBIG. A clinical trial evaluating HBIG therapy in patients was also performed.

RESULTS

In the mouse study, HBV DNA titers were reduced and serum HBsAg titers decreased to undetectable levels following high-dose HBIG injection. On the basis of this result, eight chronic hepatitis B patients, who had received long-term nucleotide analogue treatment, were treated with monthly HBIG injections as an additional treatment. After 1 year of treatment, an HBsAg level reduction of more than 1 log IU/mL was observed in four patients, and three patients became anti-HBs positive. No adverse events occurred during HBIG therapy.

CONCLUSION

These results suggest that monthly HBIG injection might benefit patients with chronic hepatitis B whose HBsAg titer becomes lower following long-term nucleotide/nucleoside analogue treatment.

Interferon Treatment for Hepatitis B

Chronic hepatitis B virus (HBV) infection has a significant public health impact. There are currently 7 approved therapies for chronic HBV, including standard and pegylated interferon (IFN)-α, and 5 nucleos(t)ide analogs (NUCs). IFN offers benefits over NUCs, including a finite duration of therapy and a higher rate of clearance of hepatitis Be antigen and surface antigen. These benefits need to be weighed against the potential adverse effects of IFN therapy. Some patients should not receive IFN because of advanced liver disease or comorbidities. This article reviews the mechanisms of action, efficacy, and clinical use of IFN therapy for HBV infection.

Treatment outcomes and validation of the stopping rule for response to peginterferon in chronic hepatitis B: A Thai nationwide cohort study

BACKGROUND AND AIMS

Peginterferon has demonstrated effectiveness in clinical trials in patients with chronic hepatitis B (CHB). However, its efficacy in real-life settings remains unclear. We investigated the efficacy of peginterferon for CHB and validated the performance of previously identified response predictors in clinical practice.

METHODS

We analyzed prospectively collected data from a Thai nationwide cohort of CHB patients treated with peginterferon alfa-2a (180 µg/week, 48 weeks).

RESULTS

Among a total of 233 patients, mostly with genotype B or C, sustained response was observed in 23% of 135 hepatitis B e antigen (HBeAg)-positive patients (HBeAg seroconversion with hepatitis B virus [HBV] DNA < 2000 IU/mL) and 42% of 98 HBeAg-negative patients (HBV DNA < 2000 IU/mL with aminotransferase normalization) at 24 weeks after treatment. Age, sex, presence of cirrhosis, genotype, and pretreatment levels of aminotransferase, HBV DNA, and hepatitis B surface antigen (HBsAg) were not identified as significant predictors of sustained response. In HBeAg-positive patients, HBsAg > 20 000 IU/mL at week 12 provided a good stopping rule, with a negative predictive value of 96%. In HBeAg-negative patients, the performance of 12-week stopping rules of no decline in HBsAg with a < 2log₁₀ decline in HBV DNA and a < 10% log₁₀ decline in HBsAg showed modest negative predictive values of 80% and 66%, respectively, for achieving sustained response.

CONCLUSION

Outcomes in CHB patients treated with peginterferon in a clinical setting are similar to those demonstrated in clinical trials. Application of the early stopping rule based on HBsAg quantification may allow individualization of therapy, particularly in HBeAg-positive patients.

Response-guided peginterferon therapy in patients with HBeAg-positive chronic hepatitis B: A randomized controlled study

BACKGROUND & AIMS

Response-guided therapy has been confirmed to be an effective strategy for the treatment of chronic hepatitis C in the pegylated interferon (PegIFN) era, but no randomized trial utilizing this strategy has been conducted in chronic hepatitis B.

METHODS

In this open-label, multicenter, randomized trial, HBeAg positive patients were treated with PegIFN (180μg/week) for 24weeks. Early responders (HBsAg <1500IU/ml and HBV DNA <10(5)copies/ml at week 24) received PegIFN for a further 24weeks (arm A), while non-early responders were randomized to PegIFN for another 24weeks (arm B), another 72weeks (arm C) or PegIFN for another 72weeks plus adefovir for 36weeks (arm D). The primary endpoint was the change of quantitative HBsAg from baseline to the end of follow-up (EOF).

RESULTS

For non-early responders, 96-week PegIFN monotherapy did not lead to a greater reduction of HBsAg from baseline to EOF, compared with 48-week PegIFN (-0.71 vs. -0.67log10IU/ml, P=0.407). The rate of HBeAg seroconversion with HBV DNA <2000IU/ml at EOF were similar for arms B, C and D (17.9%, 23.9% and 25.0% respectively). For patients with HBsAg <1500IU/ml or HBV DNA <10(5)copies/ml at week 24, 38.4% and 37.0% achieved HBeAg seroconversion with HBV DNA <2000IU/ml at EOF respectively.

CONCLUSIONS

Patients with HBsAg <1500IU/ml or HBV DNA <10(5)copies/ml at week 24 would benefit from continued PegIFN treatment. Extending the duration of PegIFN with or without adding adefovir did not show superiority over 48weeks PegIFN monotherapy.

LAY SUMMARY

Extending the duration of pegylated interferon (PegIFN) alfa-2a is not recommended in HBeAg positive patients as treatment extension beyond 48weeks did not show convincing benefit. Patients who achieved HBsAg <1500IU/ml or HBV DNA <10(5)copies/ml after 24-week PegIFNα-2a showed satisfactory outcome after the withdrawal of finite PegIFNα-2a treatment.

CLINICAL TRIAL NUMBER

NCT01086085.

Hepatitis B: encouraging the use of interferon

PURPOSE OF REVIEW

Hepatitis B is a major cause of hepatocellular carcinoma and liver cirrhosis. Interferon (IFN)-based therapies provide the highest likelihood of achieving off-treatment virological and serological control although their use is often avoided because of the side-effect profile. We review recent developments regarding the use of IFN in the treatment of chronic hepatitis B, including proposed strategies to enhance efficacy while limiting treatment exposure for patients who are unlikely to achieve acceptable treatment endpoints.

RECENT FINDINGS

The utility of host genetics (human leukocyte antigen associations and interleukin 28B) is yet to be defined. In hepatitis B e antigen (HBeAg)-positive disease, add-on IFN therapy to patients on entecavir may allow curtailment of nucleos(t)ide analogue treatment. In HBeAg-negative disease, an on-treatment stopping rule that measures decline of hepatitis B surface antigen and hepatitis B virus DNA at 12 and 24 weeks may identify up to two-thirds of poor responders. Prolonging IFN therapy to 96 weeks in patients with HBeAg-negative disease may improve virological and serological response rates. The combination of telbivudine and IFN therapy is contraindicated because of high rates of peripheral neuropathy.

SUMMARY

These findings need to be confirmed in larger trials before they can be instituted into routine clinical practice.

Chronic hepatitis B: immune pathogenesis and emerging immunotherapeutics

Hepatitis B virus (HBV) evades, subverts, activates and regulates host immune components, thereby impacting its natural history and disease pathogenesis. Recent advances in our understanding of immune interactions in chronic viral infection and tumor therapy are applicable to chronic hepatitis B (CHB). With recent successes of tumor immunotherapy, there is a renewed interest in exploring immunotherapeutics in achieving sustained and functional cure of chronic hepatitis B. In this review, we discuss aspects of host innate and adaptive immune regulatory and pathogenic responses relevant for HBV infection. We also highlight several immune modulatory approaches in clinical development to treat CHB.

Treatment strategies according to genotype for chronic hepatitis B in children

This review article was requested by editor-in-chief of this journal as 'pediatric CHB treatment' for the upcoming special issue. The main objective of chronic hepatitis B (CHB) treatment is diminishing the risk of complications related to chronic liver disease. In Asia, there are already some reports about hepatocellular carcinoma (HCC) in hepatitis B virus (HBV) infected children. The key points of treatment in children with CHB infections are selection of which patients to treat and conformation of the optimal therapy time that would reduce viral resistance. The choice of therapy is determined by the district (Western/Eastern), HBV genotype, medical accessibility, and economic state of the country. Newly developed nucleos(t)ide analogues (NAs) are potent in children with CHB. However, to improve therapeutic efficacy, physicians are recommended to follow treatment guidelines and determine the specific genotype in the CHB patient. In this article, the treatment of pediatric CHB is reviewed according to differences in genotype.

Long-term follow up of peginterferon-α-2a treatment of hepatitis B e-antigen (HBeAg) positive and HBeAg negative chronic hepatitis B patients in phase II and III studies

AIM

We analyzed the 5-year post-treatment response to peginterferon α-2a (PEG IFN-α-2a) in hepatitis B e-antigen (HBeAg) positive and negative chronic hepatitis B patients.

METHODS

One hundred and thirty-seven chronic hepatitis B (CHB) patients receiving 90 μg or 180 μg of PEG IFN-α-2a for 24 or 48 weeks in phase II or III studies were enrolled in the study, including 100 HBeAg positive patients and 37 HBeAg negative patients; 121 patients (88.4%) had genotype C.

RESULTS

Of the 137 patients, 94 received additional antiviral therapy because of viral reactivation and 43 did not receive any additional antiviral treatment during follow up. Five years upon PEG IFN-α-2a treatment, 32 patients (23.4%) who did not receive any additional antiviral agent after PEG IFN-α-2a therapy achieved a good response (normal serum alanine aminotransferase, low-level hepatitis B virus [HBV] DNA, and HBeAg negativity). Female sex and low HBV DNA levels by the end of treatment were independently associated with favorable 5-year post-treatment responses. Forty-eight-week administration of PEG IFN-α-2a showed a better response (26.4%) than 24-week administration (18.0%). Six patients (4.3%), four males and two females, cleared hepatitis B surface antigen (HBsAg) during the 5-year follow-up period.

CONCLUSION

The 48-week administration of PEG IFN-α-2a achieved better biochemical and virological responses than the 24-week administration, particularly in younger females. The 5-year post-treatment response rate was 23.4%; however, more than two-thirds of the patients received additional antiviral therapy because of viral reactivation after PEG IFN-α-2a treatment. HBsAg clearance was noted in six patients (4.3%). PEG IFN-α-2a is effective in young female patients.

Ethnic differences in incidence of hepatitis B surface antigen seroclearance in a real-life multicenter clinical cohort of 4737 patients with chronic hepatitis B infection

BACKGROUND

Hepatitis B surface antigen (HBsAg) positivity is associated with increased risk for cirrhosis and hepatocellular carcinoma (HCC). HBsAg seroclearance is thought to be rare in general, but cohort data from US patients are limited.

AIM

To determine the incidence of HBsAg seroclearance in a real-life US cohort.

METHODS

In total, 4737 patients with chronic hepatitis B from five primary care, gastroenterology and multispecialty centres, and a university medical centre were retrospectively enrolled between 2001 and 2014 with data obtained by manual review of individual patient medical records. Seroclearance was determined by loss of HBsAg seropositivity. Persistent HBsAg was confirmed by direct serology or by proxy with positive hepatitis B e-antigen (HBeAg) or HBV DNA levels.

RESULTS

HBsAg seroclearance occurred in 52 patients over 16 844 person-years (0.31% annually, 1.2% overall). Median follow-up was 32 months, and mean age 45 ± 14 years. Incidence of HBsAg seroclearance was higher in non-Asians, age >45, males, and those with baseline HBV DNA ≤10 000 IU/mL. On multivariate Cox proportional modelling, non-Asian ethnicity (HR 2.8), male sex (HR 2.1), baseline HBVDNA ≤10 000 (HR 2.0) and age >45 (HR 1.8) were significant independent predictors of seroclearance.

CONCLUSION

HBsAg seroclearance rates were lower than previously described in this real-life cohort of patients with chronic hepatitis B, especially among Asian, female and younger patients.

Combination or sequential therapy with entecavir and interferon in chronic hepatitis B patients: Current status, problems and prospects

Sixteen years have passed since the initial antiviral treatment of chronic hepatitis B (CHB). Goal of the antiviral treatment is not only to suppress viral replication, but to achieve sustained response after a limited period of treatment and then discontinuation of drugs. Nucleos(t)ide analogues (NAs) and interferons are two types of therapeutic agents with different antiviral mechanisms for treatment of CHB. Monotherapy with NAs or interferons can only achieve ideal goal in a part of CHB patients, and combination and/or sequential therapy with both is an important attempt for CHB treatment in recent years. For patients previously treated with NAs, interferons can be used to replace NAs or in combination with them for a limited period. If interferons do not show good efficacy, then NAs, alone or in combination with interferons, can be used. For patients with high viral load, initial combination therapy may show better efficacy. According to the baseline and response guidelines, the treatment plan should be optimized frequently, and the treatment compliance emphasized with maintenance, medication and examination, along with the administration of chronic diseases, in order to ensure that HBV DNA level is lower than baseline level. For those who have had a continuous drop of HBsAg and HBeAg levels, prolonged treatment or combination of the treatment with dendritic cell (DC) therapy and immunotherapy may achieve more persistent immune control.

Hepatitis B: treatment choice and monitoring for response and resistance

Despite effective preventive primary prevention with vaccination, many people remain infected with hepatitis B virus (HBV) and suffer from its complications. Effective treatments such as interferon-based regimens and oral nucleoside/nucleotides have been developed over the last 30 years, but they are not perfect. Each of the treatments has its own merits, but none can eradicate HBV from the host. As a result, regular monitoring of the response during treatment and after treatment is required. The choice and monitoring of selected treatments, new potential therapeutic agents, and treatment options for drug resistance are discussed in this review.

An Observational, Multicenter, Cohort Study Evaluating the Antiviral Efficacy and Safety in Korean Patients With Chronic Hepatitis B Receiving Pegylated Interferon-alpha 2a (Pegasys): TRACES Study

Currently, limited data are available regarding the efficacy and safety of pegylated interferon alpha-2a (PEG-IFN α-2a) in Korean patients with chronic hepatitis B (CHB), in whom hepatitis B virus (HBV) genotype C is the most common type.We collected data from 439 patients (HBeAg positive, n = 349; HBeAg negative, n = 90) with CHB who were treated with PEG-IFN α-2a as a first-line therapy from 18 institutions. Treatment responses at the end of treatment (ET) and at 6 months posttreatment (PT6) were compared between the patients who were treated for 24 weeks versus 48 weeks, and adverse events (AEs) were evaluated.In HBeAg-positive patients, those who received PEG-IFN α-2a for 48 weeks showed significantly higher HBV DNA suppression (HBV DNA < 2000 IU/mL) than those who were treated for 24 weeks (48 weeks vs 24 weeks; at ET, 44.4% vs 36.7%, P = 0.035; at PT6, 35.9% vs 13.3%, P = 0.035). The HBeAg seroconversion rate at ET was 18.1% in 48-week treatment group, which is significantly higher than the 2.2% (P < 0.001) that was seen in 24-week treatment group. This finding also continued at PT6 (29.0% vs 10.0%, P < 0.001). Following 48 weeks of treatment in HBeAg-negative patients, HBV DNA suppression at ET was higher than in HBeAg-positive patients (87.8% vs 44.4%). AEs were typical of those associated with PEG-IFN α-2a.In naïve Korean HBeAg-positive CHB patients treated with PEG-IFN α-2a, higher rates of HBV DNA suppression and HBeAg seroconversion were achieved in the 48-week treatment group than in the 24-week treatment group without additional risk of AEs.

Chronic Hepatitis B Virus Infection: Disease Revisit and Management Recommendations

Chronic hepatitis B virus (HBV) infection evolves from immune-tolerance phase, through immune clearance phase to a quiescent phase or reactivation as hepatitis B e antigen-negative hepatitis. Persistent infection may result in the development of cirrhosis and hepatocellular carcinoma (HCC). Host factors including gender, age, family history, HLA-DP, and viral factors including HBV DNA, genotypes, precore mutations, pre-S deletions, and hepatitis B surface antigen (HBsAg) level are associated with the development of these complications. Risk scores for the development of HCC have been derived. Patients with persistently elevated alanine aminotransferase levels (>30 for males; >19 U/L for females) and HBV DNA levels >2000 IU/mL should be treated. Patients with established cirrhosis with detectable HBV DNA should also be treated. The recommended first-line agents include pegylated interferon and 2 nucleos(t)ide analogs, entecavir and tenofovir. NAs require long-term treatment to maintain suppression of HBV DNA. They have been shown to decrease hepatic fibrosis, or reverse cirrhosis and to reduce the development of HCC. They have very low rates (0% to 1.2%) of resistance. HBsAg seroclearance, although the ideal endpoint, is only achievable in 10% to 12% of patients by multicenter trials usually studying relatively young patients. Patients on long-term treatment should be monitored for viral breakthrough that may be due to noncompliance or the development of resistance. Newer agents are under trials to enhance the rate of HBsAg seroclearance. However, even with the current NAs, long-term treatment of >6 years can markedly reduce the covalently closed circular DNA, the viral component responsible for initiation of viral replication.

New therapeutic agents for chronic hepatitis B

The treatment goal for chronic hepatitis B is true eradication of the hepatitis B virus, but this is rarely achieved with first-line treatment regimens because of an inability to disrupt covalently closed circular DNA and an inadequate host immune response. Therefore, new antiviral agents are needed to target various stages of the hepatitis B virus lifecycle and modulation of the immune system. This Review provides a summary of available regimens with their strengths and limitations, and highlights future therapeutic strategies to target the virus and host immune response. These new agents can hopefully lead to a finite duration of treatment, and provide a functional and durable cure for chronic hepatitis B infection.

Clinical relevance of the study of hepatitis B virus covalently closed circular DNA

Hepatitis B virus (HBV) remains a public health concern with 240 million people affected worldwide. HBV is an hepadnavirus that replicates its genome in hepatocytes. One of the key steps of the viral life cycle is the formation of cccDNA - covalently closed circular DNA - in the nucleus, the equivalent of a viral mini-chromosome that acts as a template for subsequent virus replication. Current antiviral medications are not effective in eradicating cccDNA, which can persist in the infected liver even in the absence of detectable HBV DNA or HBsAg in the blood. cccDNA cannot be measured in serum, and few surrogate markers have been proposed. Persistent cccDNA has been associated with various clinical events, including viral reactivation induced by immunosuppressive therapies, HBV recurrence after liver transplantation and hepatocellular carcinoma (HCC). cccDNA remains the main target to achieve a cure of HBV infection, thus extensive efforts are being made to develop new antiviral concepts to degrade or silence cccDNA.

Asian-Pacific clinical practice guidelines on the management of hepatitis B: a 2015 update

Worldwide, some 240 million people have chronic hepatitis B virus (HBV), with the highest rates of infection in Africa and Asia. Our understanding of the natural history of HBV infection and the potential for therapy of the resultant disease is continuously improving. New data have become available since the previous APASL guidelines for management of HBV infection were published in 2012. The objective of this manuscript is to update the recommendations for the optimal management of chronic HBV infection. The 2015 guidelines were developed by a panel of Asian experts chosen by the APASL. The clinical practice guidelines are based on evidence from existing publications or, if evidence was unavailable, on the experts' personal experience and opinion after deliberations. Manuscripts and abstracts of important meetings published through January 2015 have been evaluated. This guideline covers the full spectrum of care of patients infected with hepatitis B, including new terminology, natural history, screening, vaccination, counseling, diagnosis, assessment of the stage of liver disease, the indications, timing, choice and duration of single or combination of antiviral drugs, screening for HCC, management in special situations like childhood, pregnancy, coinfections, renal impairment and pre- and post-liver transplant, and policy guidelines. However, areas of uncertainty still exist, and clinicians, patients, and public health authorities must therefore continue to make choices on the basis of the evolving evidence. The final clinical practice guidelines and recommendations are presented here, along with the relevant background information.

Acute hepatitis B virus infection or acute exacerbation of chronic hepatitis B infection: the differential serological diagnosis

Acute exacerbations of chronic hepatitis B are common, and may even be the first presentation of hepatitis B virus (HBV) infection. Sometimes, patients involved in these scenarios may have mistaken diagnosis of acute hepatitis B. The reason for the confusion is that the two forms of infection manifestation resemble remarkably in clinical, biochemical, and serological features, such as apparent rapid onset of severe disease, advanced grades of encephalopathy, high aminotransferases and prolonged international normalized ratios (INRs), as well as positivity for HBsAg and for IgM anti-HBc antibodies and DNA detection. Therefore, these two entities cannot be distinguished easily without historical information of HBV-associated chronic infection or recent HBV exposure, information that is often inaccurate. Considering the different prognoses, treatment strategies, and the epidemiological impact in the public health context, the correct diagnosis is extremely important. Despite the lack of effective and reliable tests to differentiate between acute infection and acute exacerbation of chronic HBV infection, the expression and kinetic evaluation of viral markers present in the circulation of individuals infected, the observation of physical-chemical properties of specific antibodies, and the combination of these findings represent some strategies in serology that could assist in differentiating between the two entities, or at least in the guidance for the correct diagnosis.

A Treatment Algorithm for the Management of Chronic Hepatitis B Virus Infection in the United States: 2015 Update

Chronic hepatitis B (CHB) continues to be an important public health problem worldwide, including in the United States. An algorithm for managing CHB was developed by a panel of United States hepatologists in 2004 and subsequently updated in 2006 and 2008. Since 2008, additional data on long-term safety and efficacy of licensed therapies have become available and have better defined therapeutic options for CHB. The evidence indicates that potent antiviral therapy can lead to regression of extensive fibrosis or even cirrhosis, thus potentially altering the natural history of CHB. In addition, appropriate choice of antiviral agent can minimize the risk of resistance. This updated algorithm for managing CHB is based primarily on evidence from the scientific literature. Where data were lacking, the panel relied on clinical experience and consensus expert opinion. The primary aim of antiviral therapy for CHB is durable suppression of serum hepatitis B virus (HBV) DNA to low or undetectable levels. CHB patients who have HBV DNA >2000 IU/mL, elevated alanine aminotransferase level, and any degree of fibrosis should receive antiviral therapy regardless of their hepatitis B e antigen status. CHB patients with HBV DNA >2000 IU/mL and elevated alanine aminotransferase level but no evidence of fibrosis may also be considered for antiviral therapy. Approved antiviral therapies for CHB are interferon alfa-2b, peginterferon alfa-2a, lamivudine, adefovir, entecavir, telbivudine, and tenofovir, although the preferred first-line treatment choices are peginterferon alfa-2a, entecavir, and tenofovir. In determining choice of therapy, considerations include efficacy, safety, rate of resistance, method of administration, duration, and cost.

Quantitative hepatitis B surface antigen combined with hepatitis B e antigen as sustained virological response predictors during extended therapy with Peginterferon alfa-2a for hepatitis B e antigen-positive chronic hepatitis B

BACKGROUND

The best strategy for chronic hepatitis B patients with poor response to 48 weeks of Peginterferon-based therapy has been controversial and the predictive value of hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg) and hepatitis B virus (HBV) DNA levels for determining the sustained virological response (SVR) of these patients is uncertain.

OBJECTIVES

To optimize management of these patients and evaluate the use of these serobiomarkers to predict SVR.

STUDY DESIGN

Eighty-one patients with an unsatisfactory response after 48 weeks of Peginterferon-based therapy were treated with extended Peginterferon therapy with or without nucleo(s) tide analogues (NAs), for a total of 96 weeks of Peginterferon treatment. HBsAg, HBeAg and HBV DNA levels were measured serially during the treatment and follow-up.

RESULTS AND CONCLUSIONS

Twenty-six of 81 patients (32.1%) attained SVR during the 72-week follow-up. The SVR rate was not statistically different between groups receiving 1-year prolongation of Peginterferon with or without NAs. The serum HBsAg cut-off of 1800IU/mL at week 48 had area under curve (AUC) of 0.727, and the serum HBsAg cut-off of 1500IU/mL, combined with HBeAg loss at week 72, had AUC of 0.753 to predict SVR during the follow-up. In conclusion, extended treatment with Peginterferon with or without NAs for patients with unsatisfactory response after 48 weeks of Peginterferon-based therapy is a promising strategy to achieve SVR, and quantitative serum HBsAg at week 48 and HBsAg level combined with HBeAg loss at week 72 of therapy can predict SVR to prolongation therapy with Peginterferon.

4'-modified nucleoside analogs: potent inhibitors active against entecavir-resistant hepatitis B virus

Certain nucleoside/nucleotide reverse transcriptase (RT) inhibitors (NRTIs) are effective against human immunodeficiency virus type 1 (HIV-1) and hepatitis B virus (HBV). However, both viruses often acquire NRTI resistance, making it crucial to develop more-potent agents that offer profound viral suppression. Here, we report that 4'-C-cyano-2-amino-2'-deoxyadenosine (CAdA) is a novel, highly potent inhibitor of both HBV (half maximal inhibitory concentration [IC50 ] = 0.4 nM) and HIV-1 (IC50  = 0.4 nM). In contrast, the approved anti-HBV NRTI, entecavir (ETV), potently inhibits HBV (IC50  = 0.7 nM), but is much less active against HIV-1 (IC50  = 1,000 nM). Similarly, the highly potent HIV-1 inhibitor, 4'-ethynyl-2-fluoro-2'-deoxyadenosine (EFdA; IC50  = 0.3 nM) is less active against HBV (IC50  = 160 nM). Southern analysis using Huh-7 cells transfected with HBV-containing plasmids demonstrated that CAdA was potent against both wild-type (IC50  = 7.2 nM) and ETV-resistant HBV (IC50  = 69.6 nM for HBVETV-RL180M/S202G/M204V), whereas ETV failed to reduce HBVETV-RL180M/S202G/M204V DNA even at 1 μM. Once-daily peroral administration of CAdA reduced HBVETV-RL180M/S202G/M204V viremia (P = 0.0005) in human-liver-chimeric/ HBVETV-RL180M/S202G/M204V-infected mice, whereas ETV completely failed to reduce HBVETV-RL180M/S202G/M204V viremia. None of the mice had significant drug-related body-weight or serum human-albumin concentration changes. Molecular modeling suggests that a shallower HBV-RT hydrophobic pocket at the polymerase active site can better accommodate the slightly shorter 4'-cyano of CAdA-triphosphate (TP), but not the longer 4'-ethynyl of EFdA-TP. In contrast, the deeper HIV-1-RT pocket can efficiently accommodate the 4'-substitutions of both NRTIs. The ETV-TP's cyclopentyl ring can bind more efficiently at the shallow HBV-RT binding pocket.

CONCLUSION

These data provide insights on the structural and functional associations of HBV- and HIV-1-RTs and show that CAdA may offer new therapeutic options for HBV patients.

Kushenin Combined with Nucleos(t)ide Analogues for Chronic Hepatitis B: A Systematic Review and Meta-Analysis

Objective. To evaluate the efficacy and safety of Kushenin (KS) combined with nucleoside analogues (NAs) for chronic hepatitis B (CHB). Methods. Randomized controlled trials (RCTs) of KS combined with NAs for CHB were identified through 7 databases. Frequencies of loss of serum HBeAg, HBeAg seroconversion, undetectable serum HBV-DNA, ALT normalization, and adverse events at 48 weeks were abstracted by two reviewers. The Cochrane software was performed to assess the risk of bias in the included trials. Data were analyzed with Review Manager 5.3 software. Results. 18 RCTs involving 1684 subjects with CHB were included in the analysis. KS combined with NAs including lamivudine (LAM), entecavir (ETV), adefovir dipivoxil (ADV), and telbivudine (TLV) showed different degree of improvement in CHB indices. KS combined with NAs increased the frequency of loss of serum HBeAg, HBeAg seroconversion, undetectable HBV-DNA levels, and ALT normalization compared with single agents. It also decreased serum ALT and AST level after one-year treatment. However, KS combined with TLV did not show a significant difference in CHB indices. The side-effects of KS combined with NAs were light and of low frequency. Conclusion. KS combined with NAs improves the efficacy of NAs in CHB.

Molecular mechanisms underlying HBsAg negativity in occult HBV infection

Although genomic detection is considered the gold standard test on HBV infection identification, the HBsAg investigation is still the most frequent clinical laboratory request to diagnose HBV infection in activity. However, the non-detection of HBsAg in the bloodstream of chronic or acutely infected individuals has been a phenomenon often observed in clinical practice, despite the high sensitivity and specificity of screening assays standardized commercially and adopted in routine. The expansion of knowledge about the hepatitis B virus biology (replication/life cycle, genetic variability/mutability/heterogeneity), their biochemical and immunological properties (antigenicity and immunogenicity), in turn, has allowed to elucidate some mechanisms that may explain the occurrence of this phenomenon. Therefore, the negativity for HBsAg during the acute or chronic infection course may become a fragile or at least questionable result. This manuscript discusses some mechanisms that could explain the negativity for HBsAg in a serological profile of individuals with HBV infection in activity, or factors that could compromise its detection in the bloodstream during HBV infection.

Current and future directions for treating hepatitis B virus infection

Hepatitis B virus (HBV) persistently infects approximately 350 million people, and approximately 600000 liver-related deaths are observed per year worldwide. HBV infection is also one of the major risk factors for hepatocellular carcinoma (HCC). The persistence of serum hepatitis B e antigen (HBeAg) and high level of serum HBV DNA are thought to reflect a high HBV replication status in hepatocytes, causing cirrhosis, HCC and liver-related deaths. It has been reported that antiviral therapy, such as peginterferon and nucleos(t)ide analogues (NUCs), could suppress liver-related death by inhibiting the HBV DNA levels and inducing seroconversion from HBeAg to antibody to HBe antigen. Currently, peginterferon is widely used, but there are also several disadvantages in the use of peginterferon, such as various adverse events, the administration route and duration. It is difficult to predict the effects of treatment and interferon is contraindicated for the patients with advanced fibrosis of the liver and cirrhosis. With respect to NUCs, entecavir and tenofovir disoproxil fumarate are current the first-choice drugs. NUCs can be administered orally, and their anti-viral effects are stronger than that of peginterferon. However, because cessation of NUC administration leads to high levels of viral replication and causes severe hepatitis, they must be administered for a long time. On the other hand, the use of both interferon and NUCs cannot eliminate covalently closed circular DNA of HBV. In this review, we evaluate the natural course of chronic HBV infection and then provide an outline of these representative drugs, such as peginterferon, entecavir and tenofovir disoproxil fumarate.

Effect of Peg-interferon α-2a combined with Adefovir in HBV postpartum women with normal levels of ALT and high levels of HBV DNA

BACKGROUND & AIMS

Currently, routine antiviral treatment is not recommended for immune-tolerant subjects with chronic HBV infection. In this study, we assessed the treatment efficacy of combining Peg IFN α-2a with Adefovir (CPIA) in chronic HBV infected pregnant women with normal levels of ALT and high levels of HBV after delivery.

METHODS

Chronic hepatitis B pregnant women with normal levels of ALT and high levels of HBV DNA were treated with Telbivudine during the third trimester of their pregnancy. After childbirth, based on serological and virological parameters, the patients were either switched to CPIA treatment for 96 weeks or stopped Telbivudine treatment and followed for 48 weeks.

RESULTS

A total of 68 patients were enrolled in this study. Thirty (30/68) of them were switched to CPIA treatment after childbirth, 93.3% (28/30) of them achieved virological response, 56.7% (17/30) achieved HBeAg seroclearance and 26.7% (8/30) cleared HBsAg. The HBV DNA and HBeAg levels before CPIA treatment were negatively associated with HBeAg seroclearance. HBsAg and HBeAg levels in week 12 and week 24 after CPIA treatment were negatively associated with HBsAg seroclearance. Thirty-eight (38/68) patients did not receive antiviral treatment after childbirth, and none of them had HBeAg or HBsAg clearance.

CONCLUSION

High rates of viral response and clearance were achieved in chronic hepatitis B pregnant woman with normal levels of ALT and high levels of HBV DNA treated by CPIA after childbirth. (231 words).

The serum IL-23 level predicts the response to pegylated interferon therapy in patients with chronic hepatitis B

BACKGROUND & AIMS

This study investigated the possible use of interleukin (IL)-23 and IL-17 serum levels as indicators for anti-hepatitis B virus (HBV) therapy.

METHODS

A total of 127 patients with chronic hepatitis B (CHB) who received pegylated interferon (PegIFN) therapy, 20 chronic asymptomatic HBV carriers (AsCs) and 32 healthy controls were recruited. The serum levels of IL-23 and IL-17 were detected by ELISA. The predictive value of baseline and early on-treatment changes in the levels of IL-23 and IL-17 for therapeutic response were evaluated by receiver operating characteristic analysis. Multivariate logistic regression models were generated to identify independent factors that affect the clearance of hepatitis B e antigen (HBeAg) and the decline in hepatitis B surface antigen (HBsAg).

RESULTS

The baseline serum levels of IL-23 and IL-17 were higher in patients with CHB than in normal controls and in AsCs. High levels of pre-treatment IL-23 and IL-17 and more significant on-treatment reductions in IL-23 and IL-17 levels were observed in patients with CHB who achieved HBeAg clearance or a decline in HBsAg >1 log10  IU/ml compared with patients who were persistently HBeAg-positive or who experienced a decline in HBsAg <1 log10  IU/ml. The predictive cut-off value of IL-23 for HBeAg clearance was 135 pg/ml, and the specificity and sensitivity were 71.4% and 70% respectively. A high pre-treatment level of IL-23 was an independent factor for the prediction of the therapeutic response in patients with HBeAg-positive CHB. Early on-treatment changes of IL-23 and IL-17 showed no predictive value.

CONCLUSIONS

A high pre-treatment serum IL-23 level predicts the therapeutic response in HBeAg-positive CHB patients during PegIFN therapy.

Adding pegylated interferon to entecavir for hepatitis B e antigen-positive chronic hepatitis B: A multicenter randomized trial (ARES study)

Entecavir (ETV) is a potent inhibitor of hepatitis B viral replication, but long-term therapy may be required. We investigated whether adding on pegylated interferon (Peg-IFN) to ETV therapy enhances serological response rates. In this global investigator-initiated, open-label, multicenter, randomized trial, hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) patients with compensated liver disease started on ETV monotherapy (0.5 mg/day) and were randomized in a 1:1 ratio to either Peg-IFN add-on therapy (180 µg/week) from week 24 to 48 (n = 85) or to continue ETV monotherapy (n = 90). Response was defined as HBeAg loss with HBV DNA <200 IU/mL at week 48. Responders discontinued ETV at week 72. All patients were followed until week 96. Response was achieved in 16 of 85 (19%) patients allocated to the add-on arm versus 9 of 90 (10%) in the monotherapy arm (P = 0.095). Adjusted for HBV DNA levels before randomized therapy, Peg-IFN add-on was significantly associated with response (odds ratio: 4.8; 95% confidence interval: 1.6-14.0; P = 0.004). Eleven (13%) of the add-on-treated patients achieved disease remission after ETV cessation versus 2 of 90 (2%) of those treated with monotherapy (P = 0.007), which was 79% (11 of 14) versus 25% (2 of 8) of those who discontinued ETV (P = 0.014). At week 96, 22 (26%) patients assigned add-on versus 12 (13%) assigned monotherapy achieved HBeAg seroconversion (P = 0.036). Peg-IFN add-on led to significantly more decline in hepatitis B surface antigen, HBeAg, and HBV DNA (all P < 0.001). Combination therapy was well tolerated.

CONCLUSION

Although the primary endpoint was not reached, 24 weeks of Peg-IFN add-on therapy led to a higher proportion of HBeAg response, compared to ETV monotherapy. Add-on therapy resulted in more viral decline and appeared to prevent relapse after stopping ETV. Hence, Peg-IFN add-on therapy may facilitate the discontinuation of nucleos(t)ide analogs.

Hepatitis B virus genotypes and variants

At least 10 hepatitis B virus (HBV) genotypes (A to J) with distinct geographic distributions and several HBV mutants, including precore/core promoter mutations and pre-S/S deletion mutations, have been recognized to be not only predictive of liver disease progression but also associated with response to antiviral therapy. HBV genotype-specific pathogenesis may contribute to heterogeneous clinical outcomes in chronic hepatitis B patients across the world. For example, patients with HBV genotypes C and D infection have a lower rate of spontaneous HBeAg seroconversion. In addition, HBV genotypes C and D have a higher frequency of core promoter and pre-S mutations than genotypes A and B. Genotypes C and D also carry a higher lifetime risk of cirrhosis and HCC development than genotypes A and B. Core promoter and pre-S mutations also correlate with an increased risk of hepatocellular carcinoma (HCC). Therapeutically, genotypes A and B patients have a better response to interferon-based therapy than genotypes C and D patients, but the response to nucleos(t)ide analogs is comparable across different HBV genotypes. In conclusion, HBV genotypes and variants may serve as viral genetic markers to predict disease progression as well as help practicing physicians optimize individualized antiviral therapy in clinical practice.

Long-Term Outcome of Sequential Therapy with Lamivudine Followed by Interferon-β in Nucleoside-Naive, Hepatitis B e-Antigen-Positive Patients with Chronic Hepatitis B Virus Genotype C Infection

It is unclear whether the combination of a nucleos(t)ide analog and interferon (IFN) is superior to monotherapy for treating chronic hepatitis B. In this study, we report the long-term outcomes of sequential therapy using lamivudine followed by IFN-β. This study included 24 hepatitis B e-antigen (HBeAg)-positive patients with chronic hepatitis B virus (HBV) genotype C infection who were treated with lamivudine alone for 16-32 weeks, then with both IFN-β and lamivudine for 4 weeks, and finally with IFN-β alone for 20 weeks. All patients were followed up for 7.1±2.8 years post-treatment. The rate of response, defined as transaminase normalization, HBeAg loss, and HBV DNA <10(4) copies/mL, was 5/24 (21%) at 24 weeks post-treatment. The patients with short-term responses were younger than those with no response (P=0.039). More short-term responders had undetectable HBV DNA at the start of IFN-β compared with the nonresponders (P=0.0059). Subsequently, 4 of the 5 short-term responders remained free of the need for further drug treatment for 4.2±3.5 years post-treatment; more short-term responders remained drug free than did nonresponders (P=0.035). In conclusion, the rate of response to sequential therapy was limited in HBeAg-positive patients with chronic HBV genotype C infection at 24 weeks post-treatment. In the majority of the short-term responders, however, the response was sustainable in the long term.

HLA-DP genes polymorphisms associate with hepatitis B surface antigen kinetics and seroclearance during nucleot(s)ide analogue therapy

BACKGROUND & AIMS

Genome-wide association studies (GWAS) recently indicated that polymorphisms in the human leucocyte antigen (HLA)-DP genes were associated with risk of persistent hepatitis B virus (HBV) infection and clearance of HBV, but the effect of HLA-DP gene polymorphisms on the effect of antiviral therapy was unknown. We here investigated whether such polymorphisms were associated with decreases in HBsAg levels and seroclearance in patients who received long-term lamivudine (LAM) treatment.

METHODS

Japanese patients (202) who were hepatitis B e antigen positive at baseline, received LAM as first-line treatment, and consented to HLA-DP genotyping (HLA-DPA1 rs3077 and HLA-DPB1 rs9277535) were categorized into two cohorts, viz., a cohort who achieved virological response without rescue therapy (cohort 1) and those who did so with rescue therapy (cohort 2).

RESULTS

Serum HBsAg levels declined significantly between year 3 and 9 from baseline among cohort 1 patients possessing ≥2 A-alleles at rs3077 and rs9277535. The percentages of such patients in cohort 1 patients with decreases in HBsAg ≥0.5 log IU/ml were higher than those with <2 A-alleles (71.8% [28/39] vs. 38.9% [23/59]; P = 0.004). However, there was no significant difference in cumulative HBsAg seroclearance rates between patients with ≥2 and those with <2 A-alleles in cohort 1. In cohort 2, HBsAg seroclearance rates were higher in patients with ≥2 A-alleles than in those with <2 A-alleles (P = 0.003).

CONCLUSION

We found an association between HLA-DP polymorphisms and decreases in HBsAg levels and seroclearance among HBeAg-positive patients treated with LAM.

Variations and mutations in the hepatitis B virus genome and their associations with clinical characteristics

Hepatitis B virus (HBV) infection is major global issue, because chronic HBV infection is strongly associated with liver cancer. HBV spread worldwide with various mutations and variations. This variability, called quasispecies, is derived from no proof-reading capacity of viral reverse transcriptase. So far, thousands of studies reported that the variety of genome is closely related to the geographic distribution and clinical characteristics. Recent technological advances including capillary sequencer and next generation sequencer have made in easier to analyze mutations. The variety of HBV genome is related to not only antigenicity of HBs-antigen but also resistance to antiviral therapies. Understanding of these variations is important for the development of diagnostic tools and the appropriate therapy for chronic hepatitis B. In this review, recent publications in relation to HBV mutations and variations are updated and summarized.

Gene therapeutic approaches to inhibit hepatitis B virus replication

Acute and chronic hepatitis B virus (HBV) infections remain to present a major global health problem. The infection can be associated with acute symptomatic or asymptomatic hepatitis which can cause chronic inflammation of the liver and over years this can lead to cirrhosis and the development of hepatocellular carcinomas. Currently available therapeutics for chronically infected individuals aim at reducing viral replication and to slow down or stop the progression of the disease. Therefore, novel treatment options are needed to efficiently combat and eradicate this disease. Here we provide a state of the art overview of gene therapeutic approaches to inhibit HBV replication. We discuss non-viral and viral approaches which were explored to deliver therapeutic nucleic acids aiming at reducing HBV replication. Types of delivered therapeutic nucleic acids which were studied since many years include antisense oligodeoxynucleotides and antisense RNA, ribozymes and DNAzymes, RNA interference, and external guide sequences. More recently designer nucleases gained increased attention and were exploited to destroy the HBV genome. In addition we mention other strategies to reduce HBV replication based on delivery of DNA encoding dominant negative mutants and DNA vaccination. In combination with available cell culture and animal models for HBV infection, in vitro and in vivo studies can be performed to test efficacy of gene therapeutic approaches. Recent progress but also challenges will be specified and future perspectives will be discussed. This is an exciting time to explore such approaches because recent successes of gene therapeutic strategies in the clinic to treat genetic diseases raise hope to find alternative treatment options for patients chronically infected with HBV.

Pharmacokinetic characteristics, pharmacodynamic effect and in vivo antiviral efficacy of liver-targeted interferon alpha

Interferon alpha (IFNα) is used for the treatment of hepatitis B virus infection, and whilst efficacious, it is associated with multiple adverse events caused by systemic exposure to interferon. We therefore hypothesise that targeting IFN directly to the intended site of action in the liver would reduce exposure in blood and peripheral tissue and hence improve the safety and tolerability of IFNα therapy. Furthermore we investigated whether directing IFN to the reservoir of infection in the liver may improve antiviral efficacy by increasing local concentration in target organs and tissues. Our previous results show that the mIFNα2 fused to an ASGPR specific liver targeting antibody, DOM26h-196-61, results in a fusion protein which retains the activity of both fusion partners when measured in vitro. In vivo targeting of the liver by mIFNα2-DOM26h-196-61, hereafter referred to as targeted mIFNα2, was observed in microSPECT imaging studies in mice. In this study we show by pharmacokinetic analysis that antibody mediated liver-targeting results in increased uptake and exposure of targeted mIFNα2 in target tissues, and correspondingly reduced uptake and exposure in systemic circulation, clearance organs and non-target tissues. We also show that cytokine activity and antiviral activity of liver-targeted IFN is observed in vivo, but that, contrary to expectations, liver-targeting of mIFNα2 using ASGPR specific dAbs actually leads to a reduced pharmacodynamic effect in target organs and lower antiviral activity in vivo when compared to non-targeted mIFNα2-dAb fusions.

Improving clinical outcomes of chronic hepatitis B virus infection

Chronic hepatitis B virus (HBV) infection is a global health problem, leading to cirrhosis, hepatocellular carcinoma (HCC) and liver-related deaths. Universal hepatitis B vaccination is the most cost-effective way to eradicate HBV infection with the remarkable reduction of chronic carriage, neonatal fulminant hepatitis and childhood HCC. The introduction of highly effective antiviral agents, including lamivudine, adefovir dipivoxil, entecavir, telbivudine, tenofovir disoproxil fumarate and pegylated interferons further improve short-, medium- and long-term outcomes of chronic HBV infection, such as ALT normalization, HBV DNA suppression, HBeAg seroconversion, HBsAg seroclearance, fibrosis regression, reduction of cirrhosis, HCC, liver-related deaths and the need for liver transplantation. Above all, sustained and profound viral suppression is the key to improve the clinical outcomes of chronic hepatitis B.