Lamivudine treatment in maternally transmitted chronic hepatitis B virus infection patients

Molecular characterization of hepatitis B virus (HBV) isolated from a pediatric case of acute lymphoid leukemia, with a delayed response to antiviral treatment: a case report

BACKGROUND

Tenofovir disoproxil fumarate (TDF) is effectively used as the first-line antiviral for chronic hepatitis B virus (HBV) infection in adults and children older than 12 years. To date, no confirmed case of virologic breakthrough (VBT) in a pediatric case has been reported.

CASE PRESENTATION

Here we describe a case of a 5-year old, asymptomatically infected with HBV infection two months after chemotherapy for precursor B acute lymphoblastic leukemia (ALL). Although the 5-year old male is South African, his family originated from Guinea. At the end of the one-year follow-up, the infection progressed to chronic HBV infection, with a high viral load. At 36 weeks (8 months) post-treatment with lamivudine (LAM), there was a partial virologic response (PVR) and after 61 weeks (14 months), he was switched to TDF rescue monotherapy. Even with TDF treatment, he still experienced VBT and subsequent PVR. The full-length genome of HBV isolated 78 weeks after the switch to rescue TDF monotherapy was sequenced and belonged to genotype E. In addition to the LAM mutations (rtS256G and rtM267L), missense mutations in B-cell, T-cell, HLA class I and II-restricted epitopes emerged, which were to evade and escape host surveillance, leading to delayed viral clearance, persistence and disease progression. Two further events of VBT occurred between weeks 113 and 141 of TDF rescue-therapy. Viral loads and liver enzymes are normalizing progressively with long-term therapy.

CONCLUSION

Although the host immune reconstitution may be delayed, prolonged TDF treatment was effective in treating this pediatric case of HBV infection with VBT and PVR.

Comparing the Efficacy and Safety of Treating Chronic Hepatitis B Infection during Pregnancy with Lamivudine, Telbivudine, and Tenofovir: A Meta-analysis

Background and Aims: The perinatal transmission of hepatitis B virus (HBV) remains an important global health problem. Here, a systematic review and meta-analysis were conducted to evaluate the evidence regarding the efficacy and maternal/fetal safety of treating pregnant women with lamivudine, telbivudine (LdT), and tenofovir (TDF). Methods: A PubMed and Scopus search resulted in 1,076 records, which were reduced to 36, containing 7,717 pregnant women with chronic HBV infection and 7467 infants meeting the inclusion criteria. The latest search was in August 2019. Results: Treatment with LdT, but not lamivudine and TDF, could significantly reduce the hepatitis B virus surface antigen-positive rate (odds ratio (OR) = 0.37) in infants; it also led to higher rates of hepatitis B e antigen loss (OR = 12.14), hepatitis B e antigen seroconversion (OR = 8.93), and alanine aminotransferase normalization in mothers (OR = 1.49). Each of these treatments was able to significantly reduce HBV DNA positivity at birth (total OR = 0.19) and mother-to-child-transmission of HBV (total OR = 0.15), and to cause higher rates of HBV DNA suppression in mothers (total OR = 25.53). However, nucleos(t)ide analogues might also be involved in creatine kinase elevation (total OR = 7.48). In contrast, no significant association was found between nucleos(t)ide analogue therapy and preterm/premature births, congenital malformation, low birth weight, and abortion or fetal/infant death. The results suggested LdT's high capability of preventing mother-to-child-transmission. However, TDF failed to show significant associations to a reduced risk of mother-to-child-transmission, probably due to the low number of patients included. Conclusions: Although using either lamivudine, LdT, or TDF could lead to more favorable maternal/fetal outcomes, LdT seemed to show more potential in resolving certain infant- and maternal-related outcomes. More studies on the safety profile of such treatments are required.

Taiwan consensus statement on the management of chronic hepatitis B

The experts of Taiwan Association for the Study of Liver (TASL) have actively participated and led the guidelines on hepatitis B virus (HBV) management by Asian Pacific Association for the Study of Liver (APASL) which is the first international association for the study of liver to publish the statement on HBV management before. However, there are more and more new data on the natural history and treatment of HBV infection in the past decade. These include new application of an old biomarker (quantitative HBsAg), clinical significance of HBV genotype and naturally occurring mutations, the role of non-invasive examination in evaluating severity of hepatic fibrosis, clinical significance of outcome calculators, new drug or new combination strategies towards more effective therapy and organ transplantation including liver and non-liver transplantation. It is time to publish the guidelines on HBV management of Taiwan. Hence, TASL have conducted an expert meeting to review, to discuss and to debate the relevant literatures, followed by draft the manuscript of HBV management guidelines and recommendations. The guidelines include general management, indications for fibrosis assessment, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patient receiving immune suppression or chemotherapy and patients in the setting of liver transplantation and hepatocellular carcinoma, are also included.

INASL Guidelines on Management of Hepatitis B Virus Infection in Patients receiving Chemotherapy, Biologicals, Immunosupressants, or Corticosteroids

Hepatitis B Virus (HBV) reactivation in patients receiving chemotherapy, biologicals, immunosupressants, or corticosteroids is emerging to be an important cause of morbidity and mortality in patients with current or prior exposure to HBV infection. These patients suffer a dual onslaught of illness: one from the primary disease for which they are receiving the culprit drug that led to HBV reactivation, and the other from HBV reactivation itself. The HBV reactivation not only leads to a compromised liver function, which may culminate into hepatic failure; it also adversely impacts the treatment outcome of the primary illness. Hence, identification of patients at risk of reactivation before starting these drugs, and starting treatment aimed at prevention of HBV reactivation is the best strategy of managing these patients. There are no Indian guidelines on management of HBV infection in patients receiving chemotherapy, biologicals, immunosupressants, or corticosteroids for the treatment of rheumatologic conditions, malignancies, inflammatory bowel disease, dermatologic conditions, or solid-organ or bone marrow transplantation. The Indian National Association for Study of the Liver (INASL) had set up a taskforce on HBV in 2016, with a mandate to develop consensus guidelines for management of various aspects of HBV infection, relevant to India. In 2017 the taskforce had published the first INASL guidelines on management of HBV infection in India. In the present guidelines, which are in continuation with the previous guidelines, the issues on management of HBV infection in patients receiving chemotherapy, biologicals, immunosupressants, or corticosteroids are addressed.

Entecavir Treatment in Children and Adolescents with Chronic Hepatitis B Virus Infection

BACKGROUND

The aim of this study was to investigate the treatment response of entecavir (ETV) in children and adolescents with chronic hepatitis B (CHB) who acquired infection perinatally or during early childhood.

METHODS

A total of nine treatment-naïve patients [median aged 12.2 years (range: 2.6-18.0); five girls and four boys], with hepatitis B e antigen (HBeAg) seropositive > 6 months, alanine aminotransferase (ALT) > 2 times of upper limit of normal value (30 IU/L), were enrolled for ETV therapy. They received ETV therapy with a dose of 0.015 mg/kg/d, with a maximal dose of 0.5 mg daily for at least 52 weeks. Another 27 untreated CHB patients matched for age, sex, ALT levels, and HBeAg status were recruited as the control group. A complete response at 48-52 weeks was defined as follows: (1) normalization of ALT; (2) undetectable hepatitis B virus DNA; and (3) HBeAg/anti-HBe seroconversion. All 36 patients were retrospectively reviewed for their biochemical, serological, and virologic responses.

RESULTS

ETV-treated patients achieved rapid ALT normalization (all before 8 months of treatment) compared with the control group (p < 0.001) and they had a greater chance of achieving undetectable HBV DNA levels at Week 52 after treatment (55.6% vs. 11.1%, p = 0.013). The cumulative incidence rates of HBeAg seroconversion were similarly high in both groups (ETV group 44% at 1 year 78% at 2 years; control group 37% at 1 year 63% at 2 years, respectively). The ETV group also had a trend of better complete response than the control group (22.2% vs. 0%, p = 0.057). None of the ETV-treated patients reported significant adverse effects.

CONCLUSION

Entecavir for pediatric CHB treatment is safe and shows clinical benefits in short-term biochemical and virologic responses. Further studies to determine long-term remission and drug resistance are required.

Lamivudine resistance in children with chronic hepatitis B

Currently, although lamivudine (LAM) has a low genetic barrier, only interferon-alpha and LAM are available as a first-line treatment in children with chronic hepatitis B (CHB). LAM is a potent inhibitor of hepatitis B virus-deoxyribonucleic acid (HBV-DNA) polymerase replication by termination of the proviral HBV-DNA chain. LAM has a good safety and tolerability profile in CHB patients with hepatic decompensation. However, the main disadvantages of this HBV reverse transcriptase inhibitor are: (1) pre-existing covalently closed circular DNA cannot be eradicated by LAM, thus relapse after therapy withdrawal is frequent; and (2) although the longer LAM treatment induced the higher seroconversion rate, the risk of viral resistance increased through the selection of YMDD (tyrosine, methionine, aspartate, aspartate) motif. Insufficient suppression of viral replication leads to the emergence of resistant strains that could result in virological breakthrough which is usually followed by biochemical breakthrough. Mutant strains affects additional resistance and cross resistance, leading to drug resistance in a significant number of CHB patients. In this case, efficacy of more powerful anti-viral agents with higher genetic barrier against development of resistance is diminished. Furthermore, strains that are resistant to LAM could bring about vaccine escape mutants, decreasing the efficacy of HBV vaccine. A more potent drug with a high genetic barrier to resistance needs to be approved as the first-line treatment option for CHB in children.

Treatment of children with HBeAg-positive chronic hepatitis B: a systematic review and meta-analysis

BACKGROUND

Effective management of children with chronic hepatitis B is still an unresolved issue.

AIM

To assess the outcome of different therapeutic regimens among children with HBeAg-positive chronic hepatitis B.

METHODS

Electronic database searches identified clinical trials that completed specific periods of treatment and follow-up. Sustained response rates were defined by the loss of HBV DNA and HBeAg, and by the normalization of liver enzymes. The loss of HBsAg and seroconversion to anti-HBs were also listed.

RESULTS

Our searches found 20 eligible articles (1112 enrolled patients, 2-18 years old). Interferon-alpha therapy showed significantly higher sustained response rate and loss of HBsAg than no therapy (Odd's ratio 3.0, 95% confidence interval 1.6-5.4; and 2.3, 1.1-11.3, respectively). The sustained response rate was not significantly different between interferon and interferon plus lamivudine, or plus prednisone, or plus hepatitis B vaccine; this rate was significantly higher for interferon compared with combined interferon plus levamisole or vitamin E.

CONCLUSION

Interferon-alpha is still the most effective treatment option for children with HBeAg-positive chronic hepatitis B. Randomized trials are warranted for further comparing interferon to newer antiviral agents in terms of efficacy, safety, emergence of mutant variants, and cost/benefit ratio.

Predictive factors of lamivudine treatment success in an hepatitis B virus-infected pediatric cohort: a 10-year study

BACKGROUND

Hepatitis B virus (HBV) infections are responsible for the development of chronic hepatitis in 400 million people worldwide. Currently, no consensus exists as to when treatment should be initiated for pediatric patients.

OBJECTIVES

To evaluate the risks and predictive factors of success of lamivudine treatment in children with chronic, active HBV infection.

METHODS

Forty-three children (22 male, median age 9.6 years) chronically infected with HBV and treated between 1998 and 2008 at CHU Ste-Justine (Montreal, Quebec) were included in the present chart review study. Inclusion criteria were detectable hepatitis B surface antigen and hepatitis B e antigen (HBeAg), minimum serum alanine aminotransferase (ALT) level of two times the upper limit of normal and detectable serum HBV DNA for at least three months. Patients received lamivudine for a minimum of six months (median 14 months). Genotyping was performed.

RESULTS

Lamivudine treatment was effective in 35% of cases (15 of 43) and overall virological response (during or after treatment) was achieved in 51% of patients. Three patients harboured suspected lamivudine-resistant mutations and five progressed to HBeAg-chronic HBV. Predictive factors for success of treatment were: younger age at beginning of treatment (P=0.05), elevated ALT levels throughout treatment duration (P=0.003) and loss of HBeAg during treatment (P=0.016). Asian origin did not affect treatment success or spontaneous viral control during follow-up. HBV genotype did not influence treatment success.

CONCLUSIONS

Lamivudine treatment in a carefully selected cohort of HBV patients demonstrated a good rate of success and low incidence of mutation. Younger age at the beginning of treatment and high ALT levels during treatment predicted a positive outcome.

Lamivudine and adefovir resistance in children and young adults with chronic hepatitis B

OBJECTIVE

Long-term lamivudine (LAM) and adefovir (ADV) treatment has been found to induce the emergence of drug-resistant hepatitis B virus (HBV) in a significant number of patients with chronic hepatitis B (CHB) infection. The aim of our study was to evaluate the LAM and ADV mutations detected in our patient group.

MATERIALS AND METHODS

Twenty-four patients diagnosed with CHB were enrolled in this study. The patient group consisted of those who had received 6 months of treatment with interferon-alpha and who did not response to this therapy. Patients were evaluated based on virologic and serologic response to therapy, and were classified as responders or non-responders. The treatment of non-responders continued with LAM (3mg/kg/d, maximum 100mg/d). Due to a lack of response to treatment, ADV (10mg/g) was added to the treatment regimen of eight young adult patients. The mutations associated with HBV drug resistance were investigated using reverse hybridization methods and PCR.

RESULTS

The mutation studies indicated that 14 (58.4%) of the patients had resistance. Three patients developed ADV-associated mutations (A181T), one after 18 months of ADV; the other two had undergone 18 and 36 months of LAM therapy without ADV exposure. Although the average LAM treatment period of the patients with LAM resistance was longer than for those in whom no resistance was detected, no statistically significant difference was found.

CONCLUSIONS

HBV treatment with nucleoside analogues results in the development of mutant strains, leading to drug resistance. Therefore genotypic resistance testing is important in planning and monitoring HBV treatment.

Hepatitis B virus mutation in children

Due to the lack of proof reading activity of hepatitis B virus (HBV) polymerase, mutation/variation of the viral sequence is frequently found during long term follow-ups. In the majority of children with chronic HBV infection, wild type HBV is the dominant viral strain during the natural course of chronic HBV infection. During long-term follow-up, HBV precore mutants developed spontaneously in approximately 10 to 24% of children before HBeAg seroconversion and in around 50% of children after HBeAg seroconversion mutants. Occasionally, children may be infected primarily by mutant strains of HBV. Approximately 36% of children with fulminant hepatitis and 30% of children with acute hepatitis B were infected by precore mutants of HBV transmitted by their mothers or blood donors. In addition, after universal HBV vaccination, HBV surface gene variants emerge or are selected under the immune pressure generated by the host or by administration of hepatitis B immune globulin and hepatitis B vaccination. In HBV DNA positive children from four sequential surveys in Taiwan, the prevalence of hepatitis B surface gene a determinant mutants increased from 7.8% before the vaccination program, to 19.6%, 28.1% and 23.1% at 5, 10 and 15 years after the program. Nucleoside analogue may also induce mutant strains, which reduces the antiviral effects. The most common example is the YMDD mutation of the HBV polymerase gene after antiviral therapy with lamivudine. It developed in 19% of the treated children. In conclusion, children may be infected primarily by mutant strains of HBV either naturally during acute HBV infection. Those infected with wild type HBV initially may develop mutant strains gradually during the course of chronic infection under the host immune pressure. Vaccine escape mutants may develop after immunoprophylaxis. In addition, antiviral therapy with nucleoside analogues may also induce drug resistant mutant strains. Understanding the viral mutation status will help to design accurate strategies of immmunoprophylaxis and antiviral therapy against HBV infection.