Long-term outcomes with oral therapy in liver transplant recipients with hepatitis B

The Role of Antiviral Prophylaxis in Preventing HBV and HDV Recurrence in the Setting of Liver Transplantation

Hepatitis B virus (HBV) is a prevalent underlying disease, leading to liver transplantation (LT) for both decompensated cirrhosis and hepatocellular carcinoma (HCC). The hepatitis delta virus (HDV) affects approximately 5-10% of HBsAg carriers, accelerating the progression of liver injury and HCC. The initial introduction of HBV immunoglobulins (HBIG), and then of nucleos(t)ide analogues (NUCs), considerably improved the survival of HBV/HDV patients post-transplantation, as they helped prevent re-infection of the graft and recurrence of liver disease. Combination therapy with HBIG and NUCs is the primary post-transplant prophylaxis strategy in patients transplanted for HBV- and HDV-related liver disease. However, monotherapy with high-barrier NUCs, such as entecavir and tenofovir, is safe and also effective in some individuals who are at low risk of HBV reactivation. To address the problems of organ shortage, last-generation NUCs have facilitated the use of anti-HBc and HBsAg-positive grafts to meet the ever-increasing demand for grafts.

Renal Outcomes With Tenofovir Alafenamide in Liver Transplant Recipients

Tenofovir disoproxil fumarate (TDF) is associated with a higher risk of nephrotoxicity compared with entecavir (ETV) or tenofovir alafenamide (TAF).1,2 One-fifth of transplant recipients develop chronic kidney disease (CKD) within 5 years after transplantation, contributed by the use of nephrotoxic immunosuppressive medications.3 Prior studies conducted in the nontransplant setting reported superior renal safety in TAF compared with TDF but data in liver transplant (LT) recipients have so far been limited to small case series.1,4-6 Therefore, the goals of this study were to examine changes in renal function in a large multicenter cohort of LT recipients with chronic hepatitis B who were treated with TAF, TDF, or ETV for the prevention of hepatitis B virus (HBV) reinfection or reactivation from receipt of a positive HBV core antibody graft.

Eliminating viral hepatitis in children after liver transplants: How to reach the goal by 2030

Viral hepatitis infections are a great burden in children who have received liver transplant. Hepatotropic viruses can cause liver inflammation that can develop into liver graft fibrosis and cirrhosis over the long term. Immunological reactions due to viral hepatitis infections are associated with or can mimic graft rejection, rendering the condition difficult to manage. Prevention strategies using vaccinations are agreeable to patients, safe, cost-effective and practical. Hence, strategies to eliminate viral hepatitis A and B focus mainly on immunization programmes for children who have received a liver transplant. Although a vaccine has been developed to prevent hepatitis C and E viruses, its use is not licensed worldwide. Consequently, eliminating hepatitis C and E viruses mainly involves early detection in children with suspected cases and effective treatment with antiviral therapy. Good hygiene and sanitation are also important to prevent hepatitis A and E infections. Donor blood products and liver grafts should be screened for hepatitis B, C and E in children who are undergoing liver transplantation. Future research on early detection of viral hepatitis infections should include molecular techniques for detecting hepatitis B and E. Moreover, novel antiviral drugs for eradicating viral hepatitis that are highly effective and safe are needed for children who have undergone liver transplantation.

Antiviral prophylaxis against hepatitis B recurrence after liver transplantation: Current concepts

The advance in treatment against hepatitis B virus (HBV) infection with the development of nucleos(t)ide analogues (NAs) with high genetic barrier to resistance, including entecavir and tenofovir, has improved clinical outcomes of patients transplanted for HBV infection, by preventing HBV recurrence after liver transplantation (LT) effectively. Currently, after LT, the combination of hepatitis B immunoglobulin (HBIG) and a high-barrier NA is considered as the standard of care for prophylaxis against HBV recurrence. However, because of the high cost of intravenous high-dose HBIG, other routes of HBIG administration, such as intramuscular or subcutaneous, have come to the foreground. In addition, several transplant centres tend to use a NA as monoprophylaxis, following a short post-LT period of HBIG and NA combination. Lately, studies using HBIG-free prophylactic regimens with entecavir or tenofovir have shown promising outcomes in preventing HBV recurrence, mostly regarding patients with undetectable HBV DNA at the time of LT. Although vaccination against HBV has been an attractive prophylactic approach, its efficacy has been controversial. Moreover, further studies are needed regarding long-term outcomes of complete withdrawal anti-HBV prophylaxis. For patients transplanted for HBV/HDV co-infection, combined regimen should be administered for a longer period post-LT. Finally, the use of grafts from hepatitis B core antibody-positive donors is safe for HBV-negative recipients, with the administration of lifelong antiviral prophylaxis.

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.

The strategy and efficacy of prophylaxis against hepatitis B virus recurrence after liver transplantation for HBV-related diseases in the era of potent nucleos(t)ide analogues: A meta-analysis

OBJECTIVES

This meta-analysis aimed to evaluate the clinical outcome of liver transplant (LT) recipients under potent nucleoside or nucleotide analogue (NA)-based regimens and investigate different prophylactic schemes.

METHODS

We followed PRISMA statement to conduct this study. Two reviewers independently searched relevant literature via PubMed, Embase, Ovid MEDLINE, Web of Science and Insightmeme. Studies were included if they evaluated hepatitis B virus (HBV) recurrence under potent NA-based regimens in patients who received HBV-related LT. Primary and secondary outcomes were HBV recurrence, hepatocellular carcinoma (HCC) recurrence, all-cause and HBV recurrence-related mortality. Incidences with 95% confidence intervals were calculated and assessed by fixed and random effects models. Subgroup analyses were used to examine the impact of different treatment strategies.

RESULTS

Altogether 25 studies (N = 2327) were included, with a pooled HBV recurrence rate of 1.01% (95% CI 0.53%-1.59%). HBV viremia or hepatitis D virus superinfection did not influence HBV recurrence significantly (P = 0.23 and 0.71, respectively). The recurrence rate under an indefinite combination of potent NA and hepatitis B immunoglobulin (HBIG) was lower than that under potent NA monotherapy (P = 0.000) and similar to that under NA plus a finite course of HBIG (P = 0.48). The pooled HCC recurrence rate was 5.34% (95% CI 0.78%-12.48%). HBV recurrence-related mortality and all-cause mortality were 0% and 6.95% (95% CI 4.30%-10.08%), respectively.

CONCLUSIONS

Potent NA-based regimens provide satisfactory HBV antiviral prophylaxis and improve long-term outcomes for LT recipients. A finite combination of potent NA and HBIG is an alternative to life-long dual therapy.

Prevention of HBV Recurrence after Liver Transplant: A Review

Globally, hepatitis B virus (HBV) infection is recognized as a major risk factor for the development of hepatocellular carcinoma, and HBV-induced liver failure is one of the leading indications for liver transplantation. Until about two decades ago, liver transplantation in patients with chronic HBV infection was a relative contraindication, due to high risk of viral replication with the use of immunosuppressants which could result in graft infection. In the 1990s, hepatitis B immunoglobulin (HBIg) use significantly reduced the risk of graft infection, improving outcomes of liver transplant in patients with chronic HBV infection. However, very high costs, especially with the need for long-term use, became a major concern. With the advent of nucleos(t)ide analogs (NAs), there was less need for high-dose, long-term HBIg use to prevent HBV recurrence. Lamivudine was initially used but resistance soon became a major issue. This was followed by more potent NAs, such as entecavir and tenofovir, emerging as the more preferred agents. Additionally, the use of these antiviral agents (HBIg and/or NAs) have made it possible to use the grafts from donors with positivity for hepatitis B core antibody, allowing for expansion of the donor pool. Nevertheless, there is no consensus on management protocols, which vary significantly amongst centers. In this review, we appraise studies on management strategies used and the role of active vaccination in the prevention of HBV recurrence in post-liver transplant patients.

An expert review on the use of tenofovir alafenamide for the treatment of chronic hepatitis B virus infection in Asia

Asia has intermediate-to-high prevalence and high morbidity of hepatitis B virus (HBV) infection. The use of guideline-recommended nucleos(t)ide analogs with high barrier to resistance, such as entecavir (ETV), tenofovir disoproxil fumarate (TDF), and tenofovir alafenamide (TAF), is one of the key interventions for curbing HBV infection and associated morbidity in Asia. However, there are some challenges to the use of ETV and TDF; while ETV is associated with high resistance in lamivudine (LAM)-exposed (especially LAM-refractory) patients; bone and renal safety issues are a major concern with TDF. Hence, a panel of twenty-eight expert hepatologists from Asia convened, reviewed the literature, and developed the current expert opinion-based review article for the use of TAF in the resource-constrained settings in Asia. This article provides a comprehensive review of two large, phase 3, double-blind, randomized controlled trials of TAF versus TDF in HBeAg-negative (study 0108) and HBeAg-positive (study 0110) chronic HBV patients (> 70% Asians). These studies revealed as follows: (1) non-inferiority for the proportion of patients who had HBV DNA < 29 IU/mL; (2) significantly high rate of normalization of alanine aminotransferase levels; (3) no incidence of resistance; and (4) significantly better bone and renal safety, with TAF vs. TDF up to 144 weeks. Considering the benefits of TAF, the expert panel proposed recommendations for optimizing the use of TAF in Asia, along with guidance on specific patient groups at risk of renal or bone disease suitable for TAF therapy. The guidance provided in this article may help clinicians optimize the use of TAF in Asia.