High incidence of treatment-induced and vaccine-escape hepatitis B virus mutants among human immunodeficiency virus/hepatitis B-infected patients

HBcAb Positivity as a Risk Factor for Missing HIV RNA Undetectability after the 3TC+DTG Switch

Hepatitis B Core antibody (HBcAb) positivity is the surrogate marker of hepatitis B occult infection. This condition is not a contraindication for switching to two-drug (2DR) antiretroviral therapy; however, the removal of tenofovir may contribute to poor control of HBV replication. A multicentre retrospective cohort study investigated the impact of HBcAb positivity on HIV control in patients switching to a 2DR with Lamivudine and Dolutegravir (3TC-DTG). In this study, a comparison analysis was conducted between HBcAb-positive and -negative PLWH regarding HIV-RNA suppression, considering: (1): Target Not Detected (TND) < 20 cp/mL; (2) Target Detected (TD) < 20 cp/mL; and (3) Detectable > 20 cp/mL and <50 cp/mL and >50 copies/mL. A total of 267 patients on 2DR with 3TC-DTG were included. In comparison to HBcAb-negative, HBcAb-positive patients were older (45 years [35-54]) and had a lower CD4+ nadir (248 vs. 349 cells/mmc, p = 0.007). No difference in the maintenance of virological suppression was present in the two groups of patients before the switch. Although no patient had an HIV-RNA > 20 cp/mL after the switch, significantly fewer HBcAb-positive compared with -negative subjects resulted in TND at 12, 24, and 36 months after the switch: 52 (69.3%) versus 164 (85.4%), p = 0.004, 50 [72.5%] versus 143 [89.9%], p = 0.001, and 30 [66.7%] versus 90 [92.8%], p = 0.001, respectively. HBcAb positivity is associated with an increased risk of suboptimal HIV suppression during the 36 months after 3TC/DTG simplification. This finding reinforces the relevance of the OBI condition in PLWH and raises the issue of careful virological monitoring of such cases.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

In silico analysis of mutations associated with occult hepatitis B virus (HBV) infection in South Africa

Occult hepatitis B virus (OBI) infection is defined by the presence of viral DNA in the liver and/or serum in absence of hepatitis B surface antigen (HBsAg). While multiple studies have identified mutations that are associated with OBI, only a small portion of these mutations have been functionally characterized in vitro. Using complementary in silico approaches, the effects of OBI-associated amino acid mutations on HBV protein function in HBV/HIV-positive ART-naïve South Africans were evaluated. Two OBI-associated mutations in the PreS1 region, one in the PreS2 region, and seven in the surface region of subgenotype A1 sequences were identified as deleterious. In subgenotype A2 sequences, 11 OBI-associated mutations in the PreS1 region, seven in the PreS2 region, and 31 in the surface region were identified as deleterious. In the polymerase region, 14 OBI-associated mutations in subgenotype A1 and 71 OBI-associated mutations in subgenotype A2 were identified as deleterious. This study utilized in silico approaches to characterize the likely impact of OBI-associated mutations on viral function, thereby identifying and prioritizing candidates and reducing the significant cost associated with functional studies that are essential for mechanistic studies of the OBI phenotype.

Subclinical and Clinical Outcomes in Patients Coinfected With HIV and Chronic Hepatitis B Virus From Clinical Outpatient Centers in France: Protocol for an Ambispective, Longitudinal Cohort Study

Background

Previous large-scale studies have examined the effect of chronic hepatitis B virus (HBV) infection on overall and cause-specific mortality in individuals with HIV. However, few studies have collected data on the subclinical indicators of HBV that lead to these severe outcomes in the coinfected population.

Objective

In this study, we aim to describe the procedures of a cohort study extension aimed at assessing HBV-DNA replication, serological markers of HBV (hepatitis B e antigen [HBeAg] and hepatitis B surface antigen), and liver fibrosis and how these subclinical outcomes relate to mortality in predominately tenofovir-treated, coinfected patients with HIV-HBV. We assessed the characteristics at cohort inclusion of those who participated in the cohort extension, as well as those who did not participate due to being lost to follow-up or death.

Methods

Patients with HIV and chronic HBV who completed follow-up in a prospective cohort study conducted in 4 outpatient centers (Paris and Lyon, France; 2002-2011) were invited to participate in a cross-sectional visit from November 2016 to March 2018, during which a comprehensive evaluation of HIV- and HBV-related disease was undertaken. Virological and clinical data since the previous study visit were retrospectively collected.

Results

Of the 308 individuals enrolled in the cohort, 147 (47.7%) participated in the cross-sectional study. At this visit, most participants were HBeAg negative (111/134, 82.8% with available data), had undetectable HBV DNA (124/132, 93.9% with available data), and were undergoing antiretroviral therapy containing tenofovir disoproxil fumarate or tenofovir alafenamide (114/147, 77.6%). There were no significant differences in characteristics at cohort inclusion between those who did and did not complete the cross-sectional visit, except for a lower proportion with an AIDS-defining illness (30/147, 20.5% vs 49/161, 30.4%, respectively; P=.04). Of the 161 nonparticipating individuals, 42 (26.1%) died, 41 (25.4%) were lost to follow-up and known to be alive, and 78 (48.4%) were lost to follow-up with unknown vital status. Most differences in characteristics at cohort inclusion were observed between deceased individuals and those participating in the cross-sectional visit or those lost to follow-up. With this extension, the median follow-up time of the overall cohort is presently 9.2 years (IQR 3.4-14.6).

Conclusions

Extended follow-up of the French HIV-HBV cohort will provide important long-term data on the subclinical trajectory of HBV disease in the coinfected population. The biases due to the relatively high rate of those lost to follow-up need to be assessed in future studies of this cohort.

International Registered Report Identifier (IRRID)

DERR1-10.2196/24731

COVTree: Coevolution in OVerlapped sequences by Tree analysis server

Overlapping genes are commonplace in viruses and play an important role in their function and evolution. For these genes, molecular coevolution may be seen as a mechanism to decrease the evolutionary constraints of amino acid positions in the overlapping regions and to tolerate or compensate unfavorable mutations. Tracing these mutational sites, could help to gain insight on the direct or indirect effect of the mutations in the corresponding overlapping proteins. In the past, coevolution analysis has been used to identify residue pairs and coevolutionary signatures within or between proteins that served as markers of physical interactions and/or functional relationships. Coevolution in OVerlapped sequences by Tree analysis (COVTree) is a web server providing the online analysis of coevolving amino-acid pairs in overlapping genes, where residues might be located inside or outside the overlapping region. COVTree is designed to handle protein families with various characteristics, among which those that typically display a small number of highly conserved sequences. It is based on BIS2, a fast version of the coevolution analysis tool Blocks in Sequences (BIS). COVTree provides a rich and interactive graphical interface to ease biological interpretation of the results and it is openly accessible at http://www.lcqb.upmc.fr/COVTree/.

Current progress in the prevention of mother-to-child transmission of hepatitis B and resulting clinical and programmatic implications

There is currently no cure for hepatitis B chronic infections. Because new hepatitis B infections result mainly from perinatal transmission, preventing mother-to-child transmission is essential to reach by 2030 the goal of hepatitis B elimination set by the World Health Organization. The universal administration of hepatitis B vaccine to all infants, regardless of maternal status, starting with the birth dose, is the cornerstone of the strategy for elimination. Additional interventions, such as hepatitis B immune globulin administered to newborns and antiviral prophylaxis administered to hepatitis B infected pregnant women, may contribute to reaching the goal earlier. Hepatitis B immune globulin may remain out for reach of many pregnant women in low- and middle-income countries due to cost and logistic issues, but antivirals are cheap and do not require a cold chain for distribution. However, it has been observed that some viruses harbor mutations associated with escape from vaccine-elicited antibodies following immunization or administration of hepatitis B immune globulin. Also, resistance associated mutations have been described for several drugs used for treatment of hepatitis B infected patients as well as for the prevention of mother-to-child transmission. Whether these mutations have the potential to compromise the prevention of mother-to-child transmission or future treatment of the mother is a question of importance. We propose a review of important recent studies assessing tenofovir disoproxil fumarate for the prevention of mother-to-child transmission, and provides detailed information on the mutations possibly relevant in this setting.

Effect of hepatitis B virus (HBV) surface-gene variability on markers of replication during treated human immunodeficiency virus-HBV infection in Western Africa

BACKGROUND & AIMS

Replication markers exhibit substantial variation during chronic hepatitis B virus (HBV) infection, part of which can be explained by mutations on the surface (S) gene. We aimed to identify S-gene mutations possibly influencing the quantification of HBV replication markers (MUPIQH) in HBV genotype E infection, common to Western Africa.

METHODS

Seventy-three antiretroviral treatment (ART)-naïve human immunodeficiency virus (HIV)-HBV co-infected patients from Côte d'Ivoire, initiating anti-HBV-containing ART, had available HBV S-gene sequences. S-gene MUPIQHs were screened at ART initiation based on lower HBV-DNA or HBsAg quantification (qHBsAg) compared to wildtype. Their association with HBV virological response and qHBsAg slope during treatment was evaluated.

RESULTS

Genotype E was predominant (95.9%). At ART initiation, median HBV-DNA was 7.27 log₁₀ copies/mL (IQR = 5.26-8.33) and qHBsAg 4.08 log₁₀ IU/mL (IQR = 3.49-4.61). Twelve S-gene MUPIQHs were identified among 21 patients (28.8%): sS140L (n = 4), sD144A (n = 1), sS167L (n = 2), sS174N (n = 6), sP178Q (n = 2), sG185L (n = 2), sW191L (n = 2), sP203Q/R (n = 2), sS204N/I/R/K/T/G (n = 7), sN207T (n = 2), sF212C (n = 1) and sV224A/Y (n = 7). MUPIQHs at positions s185+s191+s224 and s178+s204 were within highly covarying networks of S-gene mutations. Older age (P = 0.02), elevated transaminases (P = 0.03) and anti-hepatitis B "e" antibody-positive serology (P = 0.009) were significantly associated with prevalent MUPIQHs at ART initiation. During treatment, baseline MUPIQHs were not associated with time-to-undetectable HBV-DNA (P = 0.7) and qHBsAg levels decreased at similar rates between those with vs without MUPIQHs (P = 0.5).

CONCLUSION

Several novel S-gene mutations were associated with reductions in replication markers among West African co-infected patients. These mutations, however, do not affect response during antiviral treatment. Their diagnostic and clinical consequences need clarification.

Hepatitis B virus genotype G and liver fibrosis progression in chronic hepatitis B and human immunodeficiency virus coinfection

INTRODUCTION

Infection with hepatitis B virus (HBV) genotype G has been associated with increased liver fibrosis levels compared with other genotypes in cross-sectional studies, yet its role in fibrosis evolution remains to be established.

METHODS

In this prospective cohort study, 158 human immunodeficiency virus (HIV)-HBV coinfected patients had available HBV genotyping at baseline. Liver fibrosis was assessed at baseline and every 6 to 12 months by the FibroTest (BioPredictive, Paris, France). Risk factors for fibrosis regression (F3-F4 to F0-F1-F2) and progression (F0-F1-F2 to F3-F4) between baseline and end of follow-up were evaluated.

RESULTS

Most patients were male (88.6%) with a median age of 39 years. HBV genotype A was more prevalent compared with other HBV genotypes (62.7% vs D = 10.8%, E = 10.8%, and G = 15.8%). Patients were followed up for a median of 83 months (IQR = 37-97). In the 43 (27.2%) patients with F3-F4 baseline liver fibrosis, 7 (16.2%) regressed to F0-F1-F2 fibrosis at the last follow-up visit. In the 115 (72.8%) with F0-F1-F2 fibrosis at baseline, 19 (16.5%) progressed to F3-F4 fibrosis at last visit. In multivariable analysis, fibrosis progression was independently associated with older age (P <0.005), baseline CD4+ cell count less than 350/mm ³ ( P <0.01), longer antiretroviral therapy duration ( P <0.03), and HBV genotype G infection (vs non-G, P <0.01). When examining averages over time, the rate of FibroTest increase was faster in genotype G vs non-G-infected patients with baseline F0-F1-F2 fibrosis ( P for interaction = 0.002).

CONCLUSION

In HIV-HBV coinfected patients, HBV genotype G is an independent risk factor for liver fibrosis progression as determined by noninvasive markers. HBV genotype G-infected patients with low initial liver fibrosis levels may require more careful monitoring.

High Prevalence of HBV Lamivudine-Resistant Mutations in HBV/HIV Co-Infected Patients on Antiretroviral Therapy in the Area with the Highest Prevalence of HIV/HBV Co-Infection in China

OBJECTIVES

We aimed to determine the prevalence of hepatitis B virus (HBV) drug-resistant mutations in patients co- infected with HBV/human immunodeficiency virus (HIV), including both drug-naïve subjects and those who received antiretroviral therapy (ART) in Guangxi, where the prevalence of HIV/HBV co-infection is highest in China.

METHODS

Two hundred and three subjects co-infected with HBV/HIV were recruited, including 123 drug-naïve patients (group 1) and 80 who received ART (group 2). The polymerase gene of HBV in the serum of all study subjects was analysed.

RESULTS

The results showed that the prevalence of HBV drug-resistant mutations in group 2 (76.5%, 95% CI 56.3-96.7) was significantly higher than that in group 1 (1.4%, 95% CI -1.4 to 4.2; χ2 = 50.955, p < 0.05). The major pattern of lamivudine (3TC)-resistant mutations is L180M+M204I+L80I (35.7%). In total, 95% of subjects with resistant mutations had cross-resistance to telbivudine and entecavir. No putative tenofovir disoproxil fumarate (TDF) resistance change was found. Five subjects (6.5%) in group 2 had HBV viral loads over 10 × 106 copies/mL. Four of them had 3TC-resistant mutations. Multivariate analysis showed that ART was the only factor associated with the development of drug-resistant mutations.

CONCLUSION

Treating HIV in HIV/HBV co-infection with antiretroviral agents may result in a very high prevalence of HBV 3TC-resistant mutations. TDF could not completely suppress HBV replication.

Low incidence of precore W28* mutant variants in treated hepatitis B virus and human immunodeficiency virus co-infected patients

The precore (pc) W28* mutation arises from immune-selective pressures during the hepatitis B "e" antigen (HBeAg)-positive phase of chronic hepatitis B virus (HBV) infection and has been linked to severe liver-related morbidity. Here, we examined the determinants of harboring this mutation and its rate of emergence in treated patients co-infected with human immunodeficiency virus (HIV) and HBV. In a three-year prospective cohort of 165 HIV-HBV co-infected patients, pcW28* mutation was determined via DNA-chip during yearly sampling. In a subgroup with liver biopsies, HBV covalently-closed circular (ccc)-DNA and total intrahepatic (IH)-DNA were quantified by real-time PCR. From respective inclusion to year-3 visits, median HBV-DNA levels decreased (5.88 log₁₀ IU/mL to <1.78 log₁₀ IU/mL, p < 0.001) and tenofovir-use increased (15.8%-71.4%, p < 0.001). At baseline, 47 of 162 (29.0%) patients had the pcW28* mutation and were more frequently HBeAg-negative (adjusted-OR = 4.37, 95%CI = 1.76-10.86) and had non-A HBV genotypes (adjusted-OR = 9.14, 95%CI = 4.05-20.66). No association with HIV-related factors was observed. In 114 patients without baseline mutation and available data, four developed incident pcW28* mutation by the end of follow-up (cumulative 3.5%, 95%CI = 1.3-9.1%). In the 32 patients with liver biopsies, 10 (31.3%) patients harboring the pcW28* mutation had significantly lower adjusted mean cccDNA (0.05 versus without = 0.43 copies/cell, p < 0.001) and total IH-DNA levels (2.31 versus without = 18.59 copies/cell, p = 0.006). In conclusion, the pcW28* mutation infrequently appeared in this co-infected study population with increased use of potent antivirals and suppressed levels of circulating virus.

Liver fibrosis regression and progression during controlled hepatitis B virus infection among HIV-HBV patients treated with tenofovir disoproxil fumarate in France: a prospective cohort study

Introduction: Long-term tenofovir disoproxil fumarate (TDF) use has been associated with significant regression of liver fibrosis during hepatitis B virus (HBV) mono-infection, yet little is known during HIV–HBV coinfection. The aim of this study was to evaluate the evolution of liver fibrosis and its determinants in TDF-treated coinfected patients.

Methods: In this prospective cohort study, 167 HIV–HBV-infected patients initiating TDF-containing antiretroviral therapy were included. Fibrosis was assessed using the FibroTest® at baseline and every six to twelve months. Risk factors for fibrosis progression (F0–F1–F2 to F3–F4) and regression (F3–F4 to F0–F1–F2) were evaluated.

Results: At baseline, 134 (80.2%) patients had detectable HBV-DNA (median = 4.93 log₁₀ IU/mL, IQR = 2.94–7.15) and 104 (62.3%) had hepatitis B “e” antigen-positive serology. Median follow-up was sixty months (IQR = 36–93). In the 47 (28.1%) patients with F3–F4 baseline fibrosis, 7/47 (14.9%) regressed to F0–F1–F2 at last follow-up visit. Fibrosis regression was significantly associated with higher CD4+ cell counts (P = 0.009) and lower fasting triglyceride levels (P = 0.007) at TDF-initiation. In the 120 (71.9%) patients with F0–F1–F2-baseline fibrosis, 20/120 (16.7%) progressed to F3–F4 at last follow-up visit. Fibrosis progression was associated with male gender (P = 0.01), older age (P = 0.001), from low/moderate HBV-endemic country (P = 0.007), lower nadir CD4+ cell count (P = 0.03), higher fasting glycaemia (P = 0.03) and anaemia (P = 0.004) at TDF-initiation. Control of HBV replication at end of follow-up was extensive (88.1%), while no HBV-related factors emerged as predictors of progression/regression. Incidence of severe liver-related events was low (n = 4, rate = 0.5/100 person-years).

Conclusions: Liver fibrosis levels are stable for most coinfected patients undergoing TDF, despite control of HBV replication. Nevertheless, a concerning amount of liver fibrosis progression did occur, which could be partly explained by metabolic abnormalities and past severe immunosuppression and requires further evaluation.

Detection and molecular characterisation of a diagnosis escape variant associated with occult hepatitis B virus in Brazil

BACKGROUND

Many studies have identified mutations in the hepatitis B surface antigen (HBsAg) as important factors limiting the ability of commercial serological assays to detect this viral antigen. However, an association between mutations in the HBsAg gene and the occurrence of occult HBV infection (OBI) in patients has not been established.

OBJECTIVES

To detect hepatitis B virus (HBV) DNA in patients with anti-HBc as a unique serological marker, a previously published, cost-effective TaqMan-based real-time polymerase chain reaction (PCR) test with minor groove binding probes was adapted for use in this study. The current study also aimed to investigate HBsAg mutations and genotypes of HBV in OBI at the Viral Hepatitis Ambulatory Clinic in Rio de Janeiro to determine any possible association.

METHODS

Intra-assay and inter-assay reproducibility were determined, and the mean coefficient of variation values obtained were 2.07 and 3.5, respectively. Probit analysis indicated that the 95% detection level was 25 IU/mL. The prevalence of OBI was investigated in 35 serum samples with an ‘anti-HBc alone’ profile from individuals who attended our clinic between 2011 and 2013.

FINDINGS

HBV DNA was detected in only one sample, resulting in an OBI rate of 2.9%. Nucleotide sequencing of the pre-S/S region was performed to genotype and analyse mutations within the HBsAg gene of this HBV DNA. The HBV in the OBI case was classified as sub-genotype A1, and a sequence analysis of the small S gene revealed 12 mutations in the major hydrophilic region compared to the consensus A1 sequence. Most of these mutations occurred in amino acid residues that have been reported as clinically relevant because they have been implicated in vaccine escape and/or inability to detect HBsAg by commercial serological assays.

MAIN CONCLUSIONS

Our study suggests the importance of specific HBsAg mutations, different from those in D, B, and C genotypes, in sub-genotype A1 HBV associated with OBI.

Mutations associated with drug resistance and prevalence of vaccine escape mutations in patients with chronic hepatitis B infection

The Brazilian public health system (SUS) has provided antiviral drugs for chronic hepatitis B treatment for over 10 years, but a system for monitoring for drug-related resistance mutations is not available. Determine the presence of HBV mutations associated with resistance to nucleos(t)ide analogs among 81 patients with chronic HBV infection in Salvador-BA-Brazil. HBV-DNA was PCR amplified with primers deduced from the rt domain at the HBV P gene, the sequence extended 1032 bp (from amino acid 1 to 344-rt domain). Those sequences were submitted to the HBV drug resistance database to retrieve each mutation according to the genotype. HBV genotype A1 (85.2%) was the most prevalent, followed by genotype A2 (4.9%), F (6.2%), and C1, D2, and D4 (1.2% each). Six patients (7%) exhibited resistance mutations to LAM, ETV, and TDF: two with patterns L180M + M204V and four with other different patterns: L80I + L180M + M204I; L80V + L180M + M204V; M204I; A194T. All of these mutations were present in patients with genotype A (four A1 and two A2). In addition, four mutations in gene S (three cases with the sI195M mutation and one with the W196L mutation), were detected, corresponding to a rate of 6% of vaccine escape mutations. Althougth the small sample size, an association was found between the occurrence of HBV resistance mutations and HBeAg positivity, co-infection with HIV and a history of treatment for HBV and/or HIV.

Complete and Incomplete Hepatitis B Virus Particles: Formation, Function, and Application

Hepatitis B virus (HBV) is a para-retrovirus or retroid virus that contains a double-stranded DNA genome and replicates this DNA via reverse transcription of a RNA pregenome. Viral reverse transcription takes place within a capsid upon packaging of the RNA and the viral reverse transcriptase. A major characteristic of HBV replication is the selection of capsids containing the double-stranded DNA, but not those containing the RNA or the single-stranded DNA replication intermediate, for envelopment during virion secretion. The complete HBV virion particles thus contain an outer envelope, studded with viral envelope proteins, that encloses the capsid, which, in turn, encapsidates the double-stranded DNA genome. Furthermore, HBV morphogenesis is characterized by the release of subviral particles that are several orders of magnitude more abundant than the complete virions. One class of subviral particles are the classical surface antigen particles (Australian antigen) that contain only the viral envelope proteins, whereas the more recently discovered genome-free (empty) virions contain both the envelope and capsid but no genome. In addition, recent evidence suggests that low levels of RNA-containing particles may be released, after all. We will summarize what is currently known about how the complete and incomplete HBV particles are assembled. We will discuss briefly the functions of the subviral particles, which remain largely unknown. Finally, we will explore the utility of the subviral particles, particularly, the potential of empty virions and putative RNA virions as diagnostic markers and the potential of empty virons as a vaccine candidate.

Reduction of covalently closed circular DNA with long-term nucleos(t)ide analogue treatment in chronic hepatitis B

BACKGROUND AND AIMS

Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA), a mini-chromosome essential for HBV replication, is supposed to be resistant to nucleos(t)ide analogue treatment. We investigated the effect of long-term nucleos(t)ide analogue treatment on cccDNA.

METHODS

Among 129 patients who had been enrolled in previous international nucleos(t)ide analogue clinical trials and had liver biopsies at baseline and one year after treatment, we recruited 43 patients on long-term continuous treatment for 72 to 145months for a third liver biopsy. Serum HBV DNA, hepatitis B surface antigen (HBsAg) levels, total intrahepatic HBV DNA (ihHBV DNA), cccDNA, HBV pregenomic RNA (pgRNA) as well as histologic changes were examined.

RESULTS

At the time of the third biopsy, serum HBV DNA levels were undetectable in all but one patient. The median levels of HBsAg, ihHBV DNA, and cccDNA were 2.88logIU/ml, 0.03copies/cell, and 0.01copies/cell, respectively. Compared to baseline levels, there was reduction of HBsAg levels by 0.54log (71.46%), ihHBV DNA levels by 2.81log (99.84%), and cccDNA levels by 2.94log (99.89%), with 49% having cccDNA levels below the detection limit. One patient had undetectable HBsAg. The median pgRNA level, measured only in the third biopsy, was 0.021copies/cell, with 40% of patients having undetectable pgRNA.

CONCLUSIONS

Long-term nucleos(t)ide analogue treatment induced marked depletion of cccDNA in the majority of patients while serum HBsAg levels, though reduced, were detectable in all but one patient. Whether cccDNA depletion is sustained and associated with better patient outcome requires further study.

LAY SUMMARY

It is generally presumed that a form of hepatitis B virus DNA, called covalently closed circular DNA (cccDNA), which hides inside the nuclei of liver cells of patients with chronic hepatitis B, cannot be reduced by antiviral treatment. The present study showed that with prolonged treatment (median period 126months), cccDNA can be markedly reduced, with 49% of liver biopsies having undetectable cccDNA. This suggests that viral replication capacity would be very low after prolonged antiviral treatment.

Decay of ccc-DNA marks persistence of intrahepatic viral DNA synthesis under tenofovir in HIV-HBV co-infected patients

BACKGROUND & AIMS

In the presence of highly-potent antivirals, persistence of hepatitis B virus (HBV) is most well-characterized by covalently-closed circular DNA (cccDNA) and total intrahepatic DNA (IH-DNA). We sought to determine how antiviral therapy could affect their levels during human immunodeficiency virus (HIV)-HBV co-infection.

METHODS

Sixty co-infected patients from a well-defined cohort with ⩾1 liver biopsy were studied. HBV cccDNA and total IH-DNA were extracted from biopsies and quantified by real-time PCR. Factors associated with intrahepatic viral load were determined using mixed-effect linear regression and half-life viral kinetics during reconstructed follow-up using non-linear exponential decay models.

RESULTS

At biopsy, 35 (58.3%) patients were hepatitis B "e" antigen (HBeAg)-positive and 33 (55.0%) had detectable plasma HBV-DNA (median=4.58log10IU/ml, IQR=2.95-7.43). Overall, median cccDNA was -0.95log10copies/cell (IQR=-1.70, -0.17) and total IH-DNA was 0.27log10copies/cell (IQR=-0.39, 2.00). In multivariable analysis, significantly lower levels of cccDNA and total IH-DNA were observed in patients with HBeAg-negative serology, nadir CD4(+) cell counts >250/mm(3), and longer cumulative TDF-duration, but not lamivudine- or adefovir-duration. In post-hoc analysis using reconstructed TDF-duration (median 29.6months, IQR=15.0-36.1, n=31), average half-life of cccDNA was estimated at 9.2months (HBeAg-positive=8.6, HBeAg-negative=26.2) and total IH DNA at 5.8months (HBeAg-positive=1.3, HBeAg-negative=13.6). Intrahepatic viral loads remained detectable for all patients, even with prolonged TDF-exposure.

CONCLUSIONS

In co-infection, TDF-use is associated with lower levels of HBV replication intermediates and cccDNA. Slow decay of intrahepatic viral loads underscores that TDF is unable to completely block intracellular viral DNA synthesis, which possibly accounts for continuous replenishment of the cccDNA pool.

LAY SUMMARY

Chronic hepatitis B virus (HBV) is a persistent infection, while the only real way of knowing the extent of this persistence is through measuring levels of virus in the liver. In this study, we examine levels of HBV in the liver among patients with both HBV and human immunodeficiency virus, or HIV, infection. It would appear that the currently available medication, namely "tenofovir", works well to decrease virus levels in the liver, but it remains at low levels despite long periods of treatment.

Overcoming drug resistance in HSV, CMV, HBV and HCV infection

Although vaccination has provided as a very efficient preventive tool, antiviral therapy is still needed to control viral infections not avoidable by prophylaxis with vaccines; those caused by viruses for which a vaccine is available, but vaccination is not universally implemented or does not result in complete, long-term protection; and in immunocompromised individuals with reduced immune control of viral replication. After more than 50 years of the first licensing for an antiherpetic drug, novel compounds for herpes-simplex viruses and human cytomegalovirus will open new strategies for better control and management of these two recurrent viral infections. Besides, the development and use of antiviral drugs for hepatitis viruses causing chronic liver disease has evolved from the unavailability of compounds targeting virus-specific pathways, to the generalization of different treatment regimes based on specific antiviral drugs, both for hepatitis B and C viruses. However, due to the nature of the viral genomes and their replication, in the face of the selective pressure imposed by antiviral drugs viral-resistant variants inevitably emerge, and specific strategies are needed to avoid, or reduce, their clinical and public health impact.

Rates and determinants of hepatitis B 'e' antigen and hepatitis B surface antigen seroclearance during long-term follow-up of patients coinfected with HIV and hepatitis B virus

OBJECTIVE

This study determines rates and risk factors associated with hepatitis B surface antigen (HBsAg) and hepatitis B 'e' antigen (HBeAg) seroclearance, two important prognostic indicators during infection with hepatitis B virus (HBV), in a large contemporary cohort of patients coinfected with HIV-HBV.

DESIGN

Prospective cohort study of predominately antiretroviral therapy (ART) experienced, coinfected patients.

METHODS

Participants enrolled in the French HIV-HBV Cohort had complete HBV serological battery conducted at inclusion and every yearly visit. Piecewise-exponential survival models were used to determine risk factors associated with seroclearance.

RESULTS

A total of 290 patients, of whom 151 (52.1%) were HBeAg positive, had been followed for a median 7.4 years (interquartile range [IQR] = 3.1-8.0). Tenofovir (TDF) containing ART became increasingly more frequent, as rates of undetectable HBV-DNA increased accordingly (at baseline = 39.3%, end of follow-up = 91.0%). In HBeAg-positive patients, 60 of 151 had HBeAg seroclearance (cumulative 46.4% at end of follow-up) after a median 3.0 years (IQR = 2.0-4.9). Overall, 17 of 290 patients had HBsAg seroclearance (cumulative 7.4% at end of follow-up) after a median 4.6 years (IQR = 2.1-7.2). Lower levels of time-averaged cumulative HBV-DNA were significantly associated with both HBeAg and HBsAg seroclearance (P < 0.001 and P = 0.01, respectively). In post hoc analysis among patients initiating TDF, incidence rates of HBeAg seroclearance peaked at year 4 of TDF treatment (13.1/100 person-years), whereas a steep drop in HBsAg seroclearance incidence rates occurred after year 3 (at year 3 = 1.2/100 person-years versus thereafter = 0.6/100 person-years).

CONCLUSION

HBsAg seroclearance and, to a lesser extent, HBeAg seroclearance remain difficult endpoints for patients coinfected with HIV-HBV to achieve. HBV-DNA suppression, associated with effective treatment, is strongly linked to seroclearance, but this mostly occurs within the first years of ART-containing highly potent anti-HBV activity.

Emergence of Lamivudine-Resistant HBV during Antiretroviral Therapy Including Lamivudine for Patients Coinfected with HIV and HBV in China

In China, HIV-1-infected patients typically receive antiretroviral therapy (ART) that includes lamivudine (3TC) as a reverse-transcriptase inhibitor (RTI) (ART-3TC). Previous studies from certain developed countries have shown that, in ART-3TC, 3TC-resistant HBV progressively emerges at an annual rate of 15–20% in patients coinfected with HIV-1 and HBV. This scenario in China warrants investigation because >10% of all HIV-infected patients in China are HBV carriers. We measured the occurrence of 3TC-resistant HBV during ART-3TC for HIV-HBV coinfection and also tested the effect of tenofovir disoproxil fumarate (TDF) used as an additional RTI (ART-3TC/TDF) in a cohort study in China. We obtained 200 plasma samples collected from 50 Chinese patients coinfected with HIV-1 and HBV (positive for hepatitis B surface antigen) and examined them for the prevalence of 3TC-resistant HBV by directly sequencing PCR products that covered the HBV reverse-transcriptase gene. We divided the patients into ART-3TC and ART-3TC/TDF groups and compared the efficacy of treatment and incidence of drug-resistance mutation between the groups. HIV RNA and HBV DNA loads drastically decreased in both ART-3TC and ART-3TC/TDF groups. In the ART-3TC group, HBV breakthrough or insufficient suppression of HBV DNA loads was observed in 20% (10/50) of the patients after 96-week treatment, and 8 of these patients harbored 3TC-resistant mutants. By contrast, neither HBV breakthrough nor treatment failure was recorded in the ART-3TC/TDF group. All of the 3TC-resistant HBV mutants emerged from the cases in which HBV DNA loads were high at baseline. Our results clearly demonstrated that ART-3TC is associated with the emergence of 3TC-resistant HBV in patients coinfected with HIV-1 and HBV and that ART-3TC/TDF reduces HBV DNA loads to an undetectable level. These findings support the use of TDF-based treatment regimens for patients coinfected with HIV-1 and HBV.

Use of hepatitis B surface and "e" antigen quantification during extensive treatment with tenofovir in patients co-infected with HIV-HBV

BACKGROUND & AIMS

In patients infected with hepatitis B virus (HBV) and HIV, hepatitis B 'e' antigen (qHBeAg) and hepatitis B surface antigen quantification (qHBsAg) may be used to predict short-term HBeAg and HBsAg loss, respectively. To determine if these quantifiable markers also provide accurate prediction of antigen loss during long-term, extensive tenofovir (TDF) treatment and to further establish qHBsAg profiles associated with HBsAg seroconversion.

METHODS

Prospective study of 111 co-infected, antiretroviral-experienced patients undergoing a TDF-containing regimen for >12 months. HBV-DNA viral load, qHBeAg [Paul Ehrlich Institute Units (PEIU)/ml] and qHBsAg were quantified at baseline and every 6-12 months. Sensitivity (Se) and specificity (Sp) of qHBeAg criteria were calculated using a time-dependent receiver operator characteristic curve, and qHBsAg profiles were developed using a group-based trajectory model.

RESULTS

After a median 74.2 months (IQR: 33.1-94.7) of TDF treatment, four patients had HBsAg seroconversion. Among the 78 (70.3%) HBeAg-positive patients, cumulative proportion with HBeAg loss was 42.0% (n = 23) at month 96. Baseline qHBeAg ≤100 PEIU/ml was the only significant factor for HBeAg loss (adjusted-HR = 2.36, 95% CI: 1.02-5.46) in multivariable analysis. In terms of predicting HBeAg-loss until month 96, qHBeAg ≤10 PEIU/ml was more accurate when evaluated at month 24 (Se = 0.73, Sp = 0.80) than month 12 (Se = 0.48, Sp = 0.90). All four patients with HBsAg seroconversion had profiles with large decreases in qHBsAg (>2 log10 IU/ml), not necessarily occurring during the first 12 months, which was infrequent in patients without seroconversion (8.4%, P < 0.001).

CONCLUSIONS

Quantifying hepatitis 'e' antigen during the first 2 years of TDF treatment is a practical tool in predicting long-term HBeAg loss. Non time-specific declines in qHBsAg may be a useful indicator of HBsAg seroconversion.

Hepatitis B and human immunodeficiency virus co-infection

Hepatitis B and human immunodeficiency virus (HBV and HIV) infection share transmission patterns and risk factors, which explains high prevalence of chronic HBV infection in HIV infected patients. The natural course of HBV disease is altered by the HIV infection with less chance to clear acute HBV infection, faster progression to cirrhosis and higher risk of liver-related death in HIV-HBV co-infected patients than in HBV mono-infected ones. HIV infected patients with chronic hepatitis B should be counseled for liver damage and surveillance of chronic hepatitis B should be performed to screen early hepatocellular carcinoma. Noninvasive tools are now available to evaluate liver fibrosis. Isolated hepatitis B core antibodies (anti-HBc) are a good predictive marker of occult HBV infection. Still the prevalence and significance of occult HBV infection is controversial, but its screening may be important in the management of antiretroviral therapy. Vaccination against HBV infection is recommended in non-immune HIV patients. The optimal treatment for almost all HIV-HBV co-infected patients should contain tenofovir plus lamivudine or emtricitabine and treatment should not be stopped to avoid HBV reactivation. Long term tenofovir therapy may lead to significant decline in hepatitis B surface Antigen. The emergence of resistant HBV strains may compromise the HBV therapy and vaccine therapy.

Persistent viremia in human immunodeficiency virus/hepatitis B coinfected patients undergoing long-term tenofovir: virological and clinical implications

Tenofovir (TDF) is considered the ideal treatment for patients coinfected with human immunodeficiency virus (HIV) and hepatitis B virus (HBV). However, certain coinfected patients exhibit incomplete viral suppression, with persistent, and sometimes transient, bouts of HBV replication. The reasons for this, including clinical effect, are unclear. A total of 111 HIV-HBV-infected patients undergoing TDF-containing antiretroviral therapy were prospectively followed. Serum HBV-DNA viral load, hepatitis surface (HBsAg) and e antigen (HBeAg) status were obtained at baseline and every 6-12 months. Amino acid (aa) changes on the polymerase gene were assessed using direct sequencing after nested polymerase chain reaction in patients with persistent viremia (PV). After a median of 74.7 months (interquartile range: 33.4-94.7), virological response (VR; <60 IU/mL) occurred in 96 of 111 (86.5%) patients. Of these, 86 of 96 (89.6%) remained completely undetectable during follow-up (stabilized VR). The remaining 10 of 96 (10.4%) patients had a transient blip of detectable HBV-DNA (transient PV), during which time 9 of 9 (100%) with available samples had detectable plasma TDF. Low-level PV (LL-PV; 61-2,000 IU/mL) was observed in 11 of 111 (9.9%) patients, the majority of which had detectable plasma TDF (8 of 9; 88.9%). High-level PV (>2,000 IU/mL) was rare (4 of 111; 3.6%) and was associated with nonadherence. At TDF initiation, patients with stabilized VR had significantly higher nadir CD4(+) count, compared to those with transient PV (P = 0.006) or LL-PV (P = 0.04). No consistent aa changes, other than those associated with lamivudine resistance, were observed in patients with persistent viremia. Importantly, HBeAg loss, HBeAg seroconversion, and HBsAg loss only occurred in patients with stabilized VR. Two patients with stabilized VR developed hepatocellular carcinoma and 2 with LL PV died, 1 of a liver-related cause.

CONCLUSION

Suboptimal HBV control during TDF treatment has a negative effect on serological outcomes, but not necessarily clinical events. Immunoregulation may provide more insight into this phenomenon.

Clinical implications of hepatitis B virus mutations: Recent advances

Hepatitis B virus (HBV) infection is a major cause of acute and chronic hepatitis, and of its long-term complications. It is the most variable among DNA viruses, mostly because of its unique life cycle which includes the activity of error-prone enzyme, reverse transcriptase, and the very high virion production per day. In last two decades, numerous research studies have shown that the speed of disease progression, reliability of diagnostic methods and the success of antiviral therapy and immunization are all influenced by genetic variability of this virus. It was shown that mutations in specific regions of HBV genome could be responsible for unwanted clinical outcomes or evasion of detection by diagnostic tools, thus making the monitoring for these mutations a necessity in proper evaluation of patients. The success of the vaccination programs has now been challenged by the discovery of mutant viruses showing amino acid substitutions in hepatitis B surface antigen (HBsAg), which may lead to evasion of vaccine-induced immunity. However, the emergence of these mutations has not yet raised concern since it was shown that they develop slowly. Investigations of HBV genetic variability and clinical implications of specific mutations have resulted in significant advances over the past decade, particularly in regard to management of resistance to antiviral drugs. In the era of drugs with high genetic barrier for resistance, on-going monitoring for possible resistance is still essential since prolonged therapy is often necessary. Understanding the frequencies and clinical implications of viral mutations may contribute to improvement of diagnostic procedures, more proper planning of immunization programs and creating the most efficient therapeutic protocols.

Epidemiology and impact of HIV coinfection with hepatitis B and hepatitis C viruses in Sub-Saharan Africa

Human immunodeficiency virus (HIV), Hepatitis B (HBV) and Hepatitis C (HCV) are blood-borne viruses with potentially shared routes of transmission. In high-income settings, the impact of antiretroviral therapy (ART) on survival has unmasked chronic liver disease from viral hepatitis B or hepatitis C as a leading cause of morbidity and mortality in individuals with HIV infection. It is now feared that progressive liver disease may threaten the success of ART programmes in developing countries, where HCV or HBV testing and monitoring are not yet systematic among HIV-infected patients and ART use is generally blind to these co-infections. We set out to review recent data from Sub-Saharan Africa, in order to build a detailed and up-to-date picture of the epidemiology and emerging impact of HBV and HCV coinfection in countries at the heart of the HIV pandemic. There is a preponderance of HIV/HBV coinfection compared to HIV/HCV in this region, and significant caveats exist regarding the accuracy of published HCV seroprevalence surveys. Morbidity and mortality of coinfection is significant, and may be further enhanced in African populations due to the influence of host, viral and environmental factors. Careful scrutiny of the coinfection problem is vital to inform an approach to directing resources, planning public health initiatives, providing clinical care, and guiding future research.

Evaluation of HBV DNA decay kinetics in patients containing both rtM204V/I mutant and wild-type HBV subpopulations during tenofovir DF (TDF) monotherapy or combination therapy with emtricitabine (FTC)/TDF

Tenofovir disoproxil fumarate (TDF) is recommended as treatment for chronic hepatitis B patients harboring lamivudine-associated resistance mutations (LAM-R, rtM204V/I ± rtL180M). This study evaluated the clinical response of rtM204V and rtM204I subpopulations to TDF by comparing their early viral load decay kinetics to wild-type (WT) subpopulations in chronic hepatitis B patients harboring rtM204V/I prior to initiating TDF or emtricitabine (FTC)/TDF therapy. Allele-specific PCR assays capable of detecting rtM204V or rtM204I subpopulations as low as 0.5% were developed and used to assess patient samples from a Phase 3b study evaluating TDF and FTC/TDF treatment in LAM-R patients. Baseline samples (n = 280) were quantified for rtM204V/I subpopulations and rtM204V or rtM204I subpopulations were detected in 269/273 (98.5%) baseline samples with a range of 0.7% to >95%. On-treatment analyses were conducted for seventeen patients (TDF, n = 8; FTC/TDF, n = 9) that harbored baseline WT and either rtM204V or rtM204I (no rtM204V/I mixtures) and HBV DNA ≥1,000 copies/ml at/after week 4. The median change in HBV DNA through week 12 for WT and rtM204V/I subpopulations was similar, -2.64 and -3.30 log10  copies/ml, respectively, with no significant difference between TDF and FTC/TDF treatment. In conclusion, rtM204V/I subpopulations demonstrate similar early HBV DNA decline kinetics to WT subpopulations during treatment with either TDF or FTC/TDF. These results demonstrate that TDF is similarly active against both WT and rtM204V/I subpopulations in vivo.