Tenofovir Alafenamide to Prevent Perinatal Hepatitis B Transmission: A Multicenter, Prospective, Observational Study

Tenofovir alafenamide or tenofovir disoproxil fumarate in pregnancy to prevent HBV transmission: Maternal ALT trajectory and infant outcomes

BACKGROUND

The use of antiviral agents, specifically tenofovir disoproxil fumarate (TDF), in pregnant women to prevent mother-to-child HBV transmission is a key step towards hepatitis elimination. However, data on using tenofovir alafenamide (TAF) is insufficient. The frequent occurrence of postpartum ALT flares may impact the clinical implementation.

METHODS

The maternal and infant outcomes were compared in multi-centre trials of high viral load HBsAg/HBeAg+ pregnant women receiving TAF or TDF from the third trimester until 2 weeks postpartum with intensive follow-ups. To explore the dynamic pre- and postpartum changes in ALT levels, we used a group-based trajectory model for analysing data of 332 women from three prospective studies.

RESULTS

After treatment, the maternal HBV DNA levels significantly decreased from baseline to delivery: 7.87 ± 0.59 to 3.99 ± 1.07 Log10 IU/mL TAF (n = 78) and 8.30 ± 0.36 to 4.47 ± 0.86 Log10 IU/mL (TDF, n = 53), with viral load reductions of 3.87 versus 3.83 Log10 IU/mL. The HBsAg-positive rates among 12-month-old infants were 1.28% (1/78) versus 1.82% (1/55) respectively (p = 1.00). Of the TAF or TDF-treated mothers, 25.64% versus 16.98% experienced ALT > 2X ULN, and 11.54% versus 1.89% received extended antiviral treatment. Our model revealed four distinct ALT patterns: stable ALT (87.2%), moderate (8.0%) or marked (2.4%) postpartum flares, or prepartum elevations (2.4%).

CONCLUSIONS

TAF effectively reduces mother-to-child HBV transmission, but prophylaxis failure still occurred in few cases. Postpartum ALT flares are common in women receiving TAF or TDF during pregnancy. Approximately 12.8% of mothers may require extended postpartum antiviral treatment.

CLINICAL TRIAL NUMBER

NCT03695029 (ClinicalTrials.gov).

Efficacy of antiviral therapy for the prevention of mother-to-child transmission of hepatitis B virus and the risk of postpartum hepatitis flare after discontinuation of antiviral therapy

The use of nucleos(t)ide analogs (NAs) is recommended for mothers with a high viral load of hepatitis B virus (HBV) during the second or third trimester of pregnancy. However, postpartum hepatitis flares can occur in some cases. We examined the efficacy of NA administration for the prevention of mother-to-child transmission of hepatitis B virus, and evaluated the risk of postpartum hepatitis flares in mothers after NA discontinuation. Nine pregnant women with a high viral load (HBV DNA ≥5.3 log IU/mL) received tenofovir disoproxil fumarate (TDF) at approximately 28 weeks of gestation, and TDF was discontinued at 4-10 weeks after delivery. We evaluated the virological and biochemical parameters in mothers after TDF discontinuation. Hepatitis flares in mothers were defined as alanine transaminase level ≥60 U/L. None of the infants developed any congenital anomaly or acquired HBV infection during infancy. Hepatitis flares occurred within 6 months after TDF discontinuation in five of seven cases, whereas two cases were lost to follow-up. Furthermore, three cases required the resumption of NA use. NA administration was highly effective against mother-to-child-transmission of HBV in pregnant women with high HBV DNA levels. However, hepatitis flares were commonly observed after NA discontinuation in the postpartum period. Patients should be followed up carefully after NA discontinuation, and NA resumption should be considered based on a comprehensive assessment of virological and biochemical parameters.

Society for Maternal-Fetal Medicine Consult Series #69: Hepatitis B in pregnancy: updated guidelines

More than 290 million people worldwide, and almost 2 million people in the United States, are infected with hepatitis B virus, which can lead to chronic hepatitis B, a vaccine-preventable communicable disease. The prevalence of chronic hepatitis B infection in pregnancy is estimated to be 0.7% to 0.9% in the United States, with >25,000 infants born annually at risk for chronic infection due to perinatal transmission. Given the burden of disease associated with chronic hepatitis B infection, recent national guidance has expanded both the indications for screening for hepatitis B infection and immunity and the indications for vaccination. The purpose of this document is to aid clinicians caring for pregnant patients in screening for hepatitis B infection and immunity status, discuss the perinatal risks of hepatitis B infection in pregnancy, determine whether treatment is indicated for maternal or perinatal indications, and recommend hepatitis B vaccination among susceptible patients. The following are the Society for Maternal-Fetal Medicine recommendations: (1) we recommend triple-panel testing (hepatitis B surface antigen screening, antibody to hepatitis B surface antigen, and total antibody to hepatitis B core antigen) at the initial prenatal visit if not previously documented or known to have been performed (GRADE 1C); (2) we recommend universal hepatitis B surface antigen screening alone at the initial prenatal care visit for all pregnancies where there has been a previously documented negative triple-panel test (GRADE 1B); (3) we recommend that individuals with unknown hepatitis B surface antigen screening status be tested on any presentation for care in pregnancy; we also recommend that those with clinical hepatitis or those with risk factors for acute hepatitis B infection be tested at the time of admission to a birthing facility when delivery is anticipated (GRADE 1B); (4) we do not recommend altering routine intrapartum care in individuals chronically infected with hepatitis B; administration of neonatal immunoprophylaxis is standard of care in these situations (GRADE 1B); (5) we do not recommend cesarean delivery for the sole indication of reducing perinatal hepatitis B virus transmission (GRADE 1B); (6) we recommend that individuals with HBV infection can breastfeed as long as the infant has received immunoprophylaxis at birth (GRADE 1C); (7) we suggest individuals with hepatitis B infection who desire invasive testing may have the procedure performed after an informed discussion on risks and benefits in the context of shared decision-making and in the context of how testing will affect clinical care (GRADE 2C); (8) in individuals with hepatitis viral loads >200,000 IU/mL (>5.3 log 10 IU/mL), we recommend antiretroviral therapy with tenofovir (tenofovir alafenamide at 25 mg daily or tenofovir disoproxil fumarate at 300 mg daily) in the third trimester (initiated at 28-32 weeks of gestation) as an adjunctive strategy to immunoprophylaxis to reduce perinatal transmission (GRADE 1B); (9) we recommend administering hepatitis B vaccine and hepatitis B immunoglobin within 12 hours of birth to all newborns of hepatitis B surface antigen-positive pregnant patients or those with unknown or undocumented hepatitis B surface antigen status, regardless of whether antiviral therapy has been given during the pregnancy to the pregnant patient (GRADE 1B); and (10) we recommend hepatitis B vaccination in pregnancy for all individuals without serologic evidence of immunity or documented history of vaccination (GRADE 1C).

Effectiveness and Safety of Tenofovir Alafenamide Fumarate in the Prevention of Perinatal Hepatitis B Transmission: A Meta-Analysis

AIM

This study aimed to assess the effectiveness and safety of tenofovir alafenamide fumarate (TAF) in the prevention of mother-to-child transmission (MTCT) of hepatitis B virus (HBV).

METHODS

We performed a meta-analysis of studies from the Cochrane Library, PubMed, ClinicalTrials.gov, Web of Science, EMBASE, China National Knowledge Infrastructure (CNKI), China Medical Information Network, and Wanfang databases. The databases were searched from inception to January 7, 2023, for cohort studies and randomized controlled trials (RCTs) comparing the use of TAF antivirals to other antivirals during pregnancy. We combined the data by means of a random-effect DerSimonian-Laird model and risk ratios (RRs) or a random-effect inverse variance model and standardized mean differences (SMDs) to determine the influence on mothers and infants. Our primary outcomes were infant weight, height, head size, birth defects, and Apgar scores. Additionally, we assessed whether newborns tested positive for hepatitis B surface antigen (HBsAg) at birth and at six months of age. The secondary outcomes of our investigation were alterations in levels of HBV deoxyribonucleic acid (DNA), alanine aminotransferase (ALT), total bilirubin (TBIL), blood creatinine, and urine β2-microglobulin (β2-M) in mothers.

RESULTS

An extensive literature search identified 216 relevant publications; three cohort studies and two RCTs were included in this study. A total of 341 mothers were treated with TAF, and 342 were treated with other antiviral agents. TAF was as effective as other antiviral medications at lowering HBV MTCT rates at birth and at 6 months of age and ALT, TBIL, and HBV DNA levels. Moreover, compared with other antiviral drugs, TAF did not affect infant weight, height, head size, Apgar scores, and birth defects or maternal blood creatinine or β2-M levels.

CONCLUSIONS

TAF antiviral therapy during pregnancy was found to be safe for both mothers and fetuses.

Maternal-to-Child Transmission of Hepatitis B Virus and Hepatitis Delta Virus

Maternal-to-child transmission of hepatitis B virus (HBV) and hepatitis delta virus (HDV) can lead to the risk of progressive liver disease in infants, but fortunately effective interventions exist to decrease transmission. Counseling on the risk of maternal-to-child transmission, care pathways to decrease transmission, and the implications of HBV and HDV on pregnancy outcomes are the key components of caring for pregnant people living with HBV and HDV.

Chronic Hepatitis B Infection: New Approaches towards Cure

Chronic hepatitis B virus (HBV) infection leads to the development of cirrhosis and hepatocellular carcinoma. Lifelong treatment with nucleotides/nucleoside antiviral agents is effective at suppressing HBV replication, however, adherence to daily therapy can be challenging. This review discusses recent advances in the development of long-acting formulations for HBV treatment and prevention, which could potentially improve adherence. Promising new compounds that target distinct steps of the virus life cycle are summarized. In addition to treatments that suppress viral replication, curative strategies are focused on the elimination of covalently closed circular DNA and the inactivation of the integrated viral DNA from infected hepatocytes. We highlight promising long-acting antivirals and genome editing strategies for the elimination or deactivation of persistent viral DNA products in development.

Enhancing interventions for prevention of mother-to-child- transmission of hepatitis B virus

Prevention of mother-to-child transmission of hepatitis B virus (HBV) infection is a cornerstone of efforts to support progress towards elimination of viral hepatitis. Current guidelines recommend maternal screening, antiviral therapy during the third trimester of high-risk pregnancies, universal and timely HBV birth dose vaccination, and post-exposure prophylaxis with hepatitis B immunoglobulin for selected neonates. However, serological and molecular diagnostic testing, treatment and HBV vaccination are not consistently deployed, particularly in many high endemicity settings, and models predict that global targets for reduction in paediatric incidence will not be met by 2030. In this article, we briefly summarise the evidence for current practice and use this as a basis to discuss areas in which prevention of mother-to-child transmission can potentially be enhanced. By reducing health inequities, enhancing pragmatic use of resources, filling data gaps, developing advocacy and education, and seeking consistent investment from multilateral agencies, significant advances can be made to further reduce vertical transmission events, with wide health, societal and economic benefits.

Low levels of tenofovir in breast milk support breastfeeding in HBV-infected mothers treated with tenofovir disoproxil fumarate

OBJECTIVE

Tenofovir disoproxil fumarate (TDF) is recommended for the prevention of mother-to-infant transmission of the hepatitis B virus (HBV). This study investigated the safety of infants whose mothers continued to receive TDF while breastfeeding.

PATIENTS AND METHOD

Thirty women taking TDF daily from the second or third trimester of pregnancy to three months postpartum were enrolled. Tenofovir (TFV) concentrations in breast milk were determined and compared with those in umbilical cord (UC) blood and amniotic fluid. Infant growth parameters were assessed at birth, and at 3, 6, and 12 months. TFV uptake experiments were conducted in vitro to elucidate the mechanisms of TFV exposure via breast milk.

RESULTS

TFV concentrations in breast milk ranged from 1.4 to 11.7 ng/mL within 24 h after dosing in the third month postpartum. The median trough concentration of TFV in breast milk was 3.7 (interquartile range, 2.6-6.2) ng/mL, which is lower than that in UC blood (median = 53.5 ng/mL) and amniotic fluid (median = 531.0 ng/mL). The low permeability of TFV in MCF-10A cells may explain the minimal exposure to TFV in breast milk. Body weights, body lengths, and head circumferences of the breastfed infants were comparable to the national standards for physical development.

CONCLUSION

Infant exposure to TFV from breast milk is much lower than the exposure from placental transfer and swallowing from amniotic fluid. The physical growth parameters of all infants in this study were normal. The findings indicate that breastfeeding is safe for infants of HBV-infected mothers who continue to receive TDF through three months postpartum.

Clinical advances: pregnancy in gastroenterologic and hepatic conditions

The fields of gastroenterology and hepatology, along with endoscopic practice, have seen significant changes and innovations to practice in just the past few years. These practice changes are not limited to gastroenterology, but maternal fetal medicine and the care of the pregnant person have become increasingly more sophisticated as well. Gastroenterologists are frequently called on to provide consultative input and/or perform endoscopy during pregnancy. To be able to provide the best possible care to these patients, gastroenterologists need to be aware of (and familiar with) the various nuances and caveats related to the care of pregnant patients who either have underlying gastrointestinal (GI) conditions or present with GI and liver disorders. Here, we offer a clinical update with references more recent than 2018, along with a few words about SARS-CoV-2 infection and its relevance to pregnancy.

The Use of Tenofovir Disoproxil Fumarate and Tenofovir Alafenamide for Preventing Vertical Transmission of Hepatitis B

BACKGROUND

Mother-to-child transmission (MTCT) of hepatitis B virus may occur in highly viremic mothers despite the infants receiving appropriate immunoprophylaxis. We aimed to review tenofovir disoproxil fumarate (TDF) and tenofovir alafenamide (TAF) data for preventing MTCT.

METHODS AND DATA SELECTION

We performed a systematic review between January 1, 2015 and December 31, 2021 on PUBMED, EMBASE, Cochrane, CNKI, and Wanfang databases. Data was extracted from randomized controlled trials or cohort studies in English or Chinese. The outcomes of interest included the efficacy and safety of TDF versus TAF or TDF/TAF versus placebo for preventing MTCT (PROSPERO registration: CRD42021256656).

RESULTS

Data from forty-three studies (13 randomized controlled trials, 30 nonrandomized studies) were included in the review. All infants in the studies received appropriate immunoprophylaxis. Among 3656 highly viremic mothers treated with TDF, hepatitis B virus DNA suppression to the levels <200,000 IU/mL at delivery was achieved in 34% to 100% of mothers. MTCT rates were 0 to 5% and 2 to 83% in mothers treated with TDF and in those who received no treatment, respectively. Congenital malformation rates were 0 to 2.1% in the TDF groups, which did not differ from the nontreated groups. Similar findings were reported in 4 studies that enrolled 326 mothers for maternal TAF therapy, resulting in 0% of MTCT and 0% infant malformation. All studies observed that TDF or TAF maternal therapy reduced MTCT rates significantly without safety concerns when compared with untreated groups, except for 1 RCT that failed the therapeutic endpoint.

CONCLUSIONS

TDF is well established for preventing MTCT in highly viremic mothers, whereas TAF may become an option as data emerges.

Management of Hepatitis B and C during Pregnancy: Neonatal Implications

Over the last several decades, we have seen increased rates of infants born to persons with chronic hepatitis B virus (HBV) and hepatitis C virus (HCV). Due to this, many obstetric and pediatric organizations have updated their guidelines about screening and management of HBV and HCV during pregnancy, as well as the management of the exposed infant. Current guidelines suggest that all pregnant individuals should be screened for both HBV and HCV during each pregnancy. Appropriate medical care of pregnant persons and the newborn can significantly reduce the risk of vertical transmission.

Current Best Practice in Hepatitis B Management and Understanding Long-term Prospects for Cure

The hepatitis B virus (HBV) is a major cause of cirrhosis and hepatocellular carcinoma worldwide. Despite an effective vaccine, the prevalence of chronic infection remains high. Current therapy is effective at achieving on-treatment, but not off-treatment, viral suppression. Loss of hepatitis B surface antigen, the best surrogate marker of off-treatment viral suppression, is associated with improved clinical outcomes. Unfortunately, this end point is rarely achieved with current therapy because of their lack of effect on covalently closed circular DNA, the template of viral transcription and genome replication. Major advancements in our understanding of HBV virology along with better understanding of immunopathogenesis have led to the development of a multitude of novel therapeutic approaches with the prospect of achieving functional cure (hepatitis B surface antigen loss) and perhaps complete cure (clearance of covalently closed circular DNA and integrated HBV DNA). This review will cover current best practice for managing chronic HBV infection and emerging novel therapies for HBV infection and their prospect for cure.

Tenofovir Alafenamide for Pregnant Chinese Women With Active Chronic Hepatitis B: A Multicenter Prospective Study

BACKGROUND & AIMS

Data on long-term tenofovir alafenamide (TAF) therapy for pregnant women with active chronic hepatitis B (CHB) (immune clearance and reactivation phases, currently and previously diagnosed) and their infants are lacking.

METHODS

Pregnant women with active CHB treated with TAF and tenofovir disoproxil fumarate (TDF) were enrolled in this multicenter prospective study, and infants received immunoprophylaxis. The primary outcomes were rates of adverse (safety) events in pregnant women and defects in infants and fetuses. The secondary outcomes were virologic responses in pregnant women, infants' safety, hepatitis B surface antigen (HBsAg) status, and growth conditions.

RESULTS

One hundred three and 104 pregnant women were enrolled and 102 and 104 infants were born in the TAF and TDF groups, respectively. In the TAF group, the mean age, gestational age, alanine aminotransferase level, and viral loads at treatment initiation were 29.3 years, 1.3 weeks, 122.2 U/L, and 5.1 log₁₀ IU/mL, respectively. TAF was well-tolerated, and the most common adverse event was nausea (29.1%) during a mean of 2 years of treatment. Notably, 1 (1.0%) TAF-treated pregnant woman underwent induced abortion due to noncausal fetal cleft lip and palate. No infants in either group had birth defects. In the TAF group, the hepatitis B e antigen seroconversion rate was 20.7% at postpartum month 6, infants had normal growth parameters, and no infants were positive for HBsAg at 7 months. The TDF group had comparable safety and effectiveness profiles.

CONCLUSIONS

TAF administered throughout or beginning in early pregnancy is generally safe and effective for pregnant women with active CHB and their infants.

Tenofovir alafenamide in blocking mother-to-child transmission of hepatitis B virus: a multi-center, prospective study

BACKGROUND

Data of tenofovir alafenamide (TAF) in preventing mother-to-child transmission (MTCT) of hepatitis B virus (HBV) are limited. This study aimed to evaluate the effectiveness and safety of TAF for preventing MTCT.

METHODS

Pregnant women with chronic HBV infection, positive for HBeAg and high-level HBV DNA, received oral TAF from gestational weeks 24-28 until postpartum week 4. All infants received HBV immunoprophylaxis. All mothers and infants were followed up until postpartum seven month. The primary outcome was the rate of MTCT at seven month.

RESULTS

Eighty-nine mothers delivered and 91 infants were born. All were followed up to postpartum seven month. TAF was initiated at a mean gestational age of 25.0 (±1.0) weeks with the mean treatment duration of 14.3 (±1.2) weeks before delivery; 92.1% (82/89) mothers discontinued TAF, the median [IQR] time was 5.9 [4.7] weeks postpartum. The HBsAg positive rate was 0% at seven months in 91 infants, no growth retardation and congenital defects. All mothers were tolerated during TAF treatment. At delivery, 82.02% (73/89) mothers achieved HBV DNA < 200,000 IU/ml, 21.35% (19/89) achieved HBV DNA < 500 IU/ml. No significant changes on the mean (±SD) serum phosphate between baseline (1.20 ± 0.10 mmol/L) and at delivery (1.21 ± 0.13 mmol/L, p > .05). Serum creatinine at delivery (52.23 ± 8.50 µmol/L) was higher than baseline (45.97 ± 5.60 µmol/L, p < .05), but within normal range. Nine of 82 mothers stopped TAF treatment after delivery had mild ALT elevation.

CONCLUSION

TAF therapy initiated during the second trimester was effective in preventing MTCT with no safety concerns for mothers and infants (ClinicalTrials.gov number, NCT04065230).

Management Algorithm for Prevention of Mother-to-child Transmission of Hepatitis B Virus (2022)

The World Health Organization (WHO) has set the goal of eliminating hepatitis as a threat to public health by 2030. Blocking mother-to-child transmission (MTCT) of hepatitis B virus (HBV) is not only the key to eliminating viral hepatitis, but also a hot issue in the field of hepatitis B prevention and treatment. To standardize the clinical management of preventing MTCT of HBV and achieve zero HBV infection among infants, the Chinese Foundation for Hepatitis Prevention and Control organized experts to compile a management algorithm for prevention of MTCT of HBV based on the latest research progress and guidelines, including 10 steps of pregnancy management and postpartum follow-up, among which screening, antiviral treatment, and infant immunization are its core components.

The role of tenofovir disoproxil fumarate for preventing vertical transmission of hepatitis B

Background

Since immunoprophylaxis failure can occur if maternal serum hepatitis B virus (HBV) DNA levels are >200,000 IU/ml, tenofovir disoproxil fumarate (TDF) therapy has been investigated for preventing mother to child transmission (PMTCT).

Methods

A literature search for maternal TDF therapy for PMTCT between 1/1/2015 and 7/1/21 on PUBMED, EMBASE, Cochrane, CNKI, and Wanfang databases was performed. Data from RCTs in English or Chinese were extracted and reviewed. The outcomes of interest included the efficacy and safety of TDF versus placebo for PMTCT.

Results

Among 11 RCTs identified from the databases, the risk-of-bias was low. All studies demonstrated that maternal TDF therapy initiated from the second or third trimester for highly viremic chronic hepatitis B mothers is highly effective and safe in the PMTCT of HBV, except one RCT performed in Thailand which showed no therapeutic advantage on TDF treatment versus placebo for PMTCT (0% vs 3% transmission). Recent emerging data suggest that maternal TDF therapy initiated at the 2nd or early 3rd trimester in mothers with HBV DNA >200,000 IU/ml achieved viremic control before delivery. In the 4-year long follow-up study for maternal TDF therapy, there were no impacts on infants’ physical growth, psychological or mental development, and bone mineral density after fetal exposure to TDF. In the light of updated efficacy and safety data from RCTs, an algorithm was proposed. The approaches in resource-limit areas were discussed.

Conclusions

TDF is safe for both mothers and infants as the preferred therapy for PMTCT in highly viremic mothers. TDF should be initiated at the second or early third trimester in the combination of the appropriate infants’ immunoprophylaxis.

Review article: switching patients with chronic hepatitis B to tenofovir alafenamide-a review of current data

BACKGROUND

The nucleos(t)ide analogues (NAs) entecavir (ETV), tenofovir disoproxil fumarate (TDF) and tenofovir alafenamide (TAF) are preferred treatment options for patients with chronic hepatitis B infection (CHB). However, resistance to ETV has been reported, especially with prior exposure to other NAs, and long-term TDF treatment has been associated with decline in renal function and loss of bone mineral density in some patients. Consequently, TAF may be preferable to ETV, TDF or other NAs in specific circumstances such as in patients with risk of bone or renal complications, elderly patients or those with previous NA experience.

AIM

To provide a summary of the available efficacy and safety data following switch to TAF from other NAs in patients with CHB in clinical studies and real-world settings.

METHODS

Literature searches were performed on PubMed and abstracts from three major international liver congresses between 2019 and 2021. Studies that included efficacy and/or safety data for patients with CHB switching from any NA to TAF were selected.

RESULTS

Thirty-six papers and abstracts were included in this narrative review. Switching from TDF to TAF maintained or improved virological and biochemical responses with improved bone and renal safety. Switching from ETV or other NAs to TAF maintained or improved virological and biochemical responses and varying results for bone and renal safety.

CONCLUSIONS

Switching to TAF appears to maintain or improve virological, biochemical and bone- and renal-related safety outcomes. These data support the concept of switching to TAF in some patients with CHB based on their individual circumstances.

Asian Pacific association for the study of liver (APASL) guidelines: hepatitis B virus in pregnancy

Hepatitis B virus (HBV) infection still remains a major public health issue in the Asia-Pacific region. Most of the burden of HBV-related disease results from infections acquired in infancy through perinatal or early childhood exposure to HBV in Asia-Pacific. Hepatitis B during pregnancy presents unique management issues for both the mother and fetus. These APASL guidelines provide a comprehensive review and recommendations based on available evidence in the literature, for the management of females with HBV infection through every stage of pregnancy and postpartum. These also address the concerns, management challenges, and required follow-up of children born to hepatitis B-positive mothers.

Safety and Efficacy of Tenofovir Alafenamide Fumarate in Early-Middle Pregnancy for Mothers With Chronic Hepatitis B

Background

Tenofovir alafenamide fumarate has been used in late pregnancy; however, no data exist regarding its safety and effectiveness in early and middle pregnancy for mothers with hepatitis B virus infection.

Aims

To design a prospective study to investigate the efficacy and safety of TAF in pregnant women with chronic HBV infection during early-middle pregnancy.

Methods

Pregnant women with active chronic hepatitis B who received tenofovir alafenamide fumarate during early and middle pregnancy were enrolled and followed up until 6 months postpartum. Infants received immunoprophylaxis. The primary endpoint was the safety of mothers and infants. The secondary endpoints were maternal hepatitis B virus DNA reduction at delivery and mother-to-child transmission rate.

Results

Among 98 mothers enrolled, 31 initiated tenofovir alafenamide fumarate in early pregnancy, and 57 in middle pregnancy. The mean (± standard deviation) age was 29.00 (±3.81) years. At delivery, 100% (98/98) of the mothers achieved hepatitis B virus DNA levels <200,000 IU/L. Ninety-eight infants were born, and none had congenital defects or malformations. All infants received hepatitis B virus immunoprophylaxis. The mother-to-child transmission rate was 0%. Growth parameters including body weight, height, and head circumference were comparable to the national standards for physical development. No severe adverse effects were reported in either mothers or infants. No severe liver function damage occurred in any of the mothers.

Conclusions

Initiating tenofovir alafenamide fumarate in early and middle pregnancy appears safe for both mothers and infants, and it is effective for controlling maternal disease as well as interrupting mother-to-child transmission.

Hepatitis B: Who should be treated?-managing patients with chronic hepatitis B during the immune-tolerant and immunoactive phases

New hepatitis B virus (HBV) infections are decreasing owing to improved antiviral therapy and increased HBV vaccination worldwide; however, the number of HBV infections remains a major cause of liver carcinogenesis. HBV triggers cytotoxic immunity to eliminate HBV-infected cells. Therefore, the HBV pathophysiology changes in persistently infected individuals depending on host immune responses and HBV DNA proliferation state. To prevent liver cirrhosis and carcinogenesis caused by HBV, it is important to treat HBV infection at an early stage. Active treatment is recommended for the immunoactive hepatitis B surface-antigen-positive and -negative phase, but not during the immune-inactive phase or immune-tolerant phase; instead, follow-up is recommended. However, these patients should be monitored through regular blood tests to accurately diagnose the immune-inactive or -tolerant phases. The treatment regimen should be determined based on the age, sex, family history of liver cancer, and liver fibrosis status of patients. Early treatment is often recommended due to various problems during the immune-tolerant phase. This review compares the four major international practice guidelines, including those from the Japanese Society of Hepatology, and discusses strategies for chronic hepatitis B treatment during the immune-tolerant, immune-inactive, and resolved phases. Finally, recommended hepatitis B antiviral therapy and follow-up protocols are discussed.

Efficacy and safety of tenofovir disoproxil fumarate and tenofovir alafenamide fumarate in preventing HBV vertical transmission of high maternal viral load

BACKGROUND

Hepatitis B virus (HBV) infection is a significant global health problem and > 42-52% of patients are infected during perinatal period. Tenofovir alafenamide fumarate (TAF) and tenofovir disoproxil fumarate (TDF) have been widely recognized as the main compounds used for antiviral treatment of hepatitis B. The present study evaluated the efficacy and safety of TAF in reducing HBV vertical transmission.

METHODS

A total of 72 pregnant women, who met the inclusion criteria, were randomly divided into the TDF (300 mg/day, n = 36) and TAF (25 mg/day, n = 36) groups. Clinical and laboratory data were analyzed and compared between the two groups.

RESULTS

No significant differences in alanine aminotransferase, total bilirubin, blood creatinine and blood urea nitrogen levels were noted between the two groups after treatment. The serum HBV DNA viral load and hepatitis B e antigen (HBeAg) levels of the two groups were significantly decreased following treatment, whereas the difference between the two groups was not statistically significant. The levels of urine retinol-binding protein and β2-microglobulin had no significant change after TAF treatment (p > 0.05), but increased significantly after TDF treatment (p < 0.05). All drug concentrations were undetectable in umbilical cord blood (UCB) and breast milk samples of the TAF group, while the drug concentration of UCB and breast milk samples in the TDF group was 2.98 ± 1.44 and 19.16 ± 15.26 ng/ml, respectively. All infants were tested negative for serum hepatitis B surface antigen, HBV DNA, and HBeAg.

CONCLUSIONS

Both TAF and TDF effectively block the mother-to-child transmission of hepatitis B. TAF was superior to TDF with regard to renal safety and breastfeeding.

Tenofovir Alafenamide Rescues Renal Tubules in Patients with Chronic Hepatitis B

Nucles(t)ide analogs (NAs) are effective for chronic hepatitis B (CHB). NAs suppress hepatic decompensation and hepatocarcinogenesis, leading to a dramatic improvement of the natural course of patients with CHB. However, renal dysfunction is becoming an important issue for the management of CHB. Renal dysfunction develops in patients with the long-term treatment of NAs including adefovir dipivoxil and tenofovir disoproxil fumarate. Recently, several studies have reported that the newly approved tenofovir alafenamide (TAF) has a safe profile for the kidney due to greater plasma stability. In this mini-review, we discuss the effectiveness of switching to TAF for NAs-related renal tubular dysfunction in patients with CHB.