Discontinuation of Passive Immunization Is Safe after Liver Transplantation for Combined HBV/HDV Infection

EASL Clinical Practice Guidelines on hepatitis delta virus

Hepatitis D virus (HDV) is a defective virus that requires the hepatitis B virus to complete its life cycle and cause liver damage in humans. HDV is responsible for rare acute and chronic liver diseases and is considered the most aggressive hepatitis virus. Acute infection can cause acute liver failure, while persistent infection typically causes a severe form of chronic hepatitis which is associated with rapid and frequent progression to cirrhosis and its end-stage complications, hepatic decompensation and hepatocellular carcinoma. Major diagnostic and therapeutic innovations prompted the EASL Governing Board to commission specific Clinical Practice Guidelines on the identification, virologic and clinical characterisation, prognostic assessment, and appropriate clinical and therapeutic management of HDV-infected individuals.

Transplantation of hepatitis D virus patients: Lifelong hepatitis B immunoglobulins?

The introduction of Hepatitis B Immunoglobulins (HBIg) prophylaxis at and after liver transplantation (LT) facilitated excellent long-term survival of transplant patients with chronic hepatitis B virus (HBV) infection. Several studies suggested that only short-term (i.e. 4-8 weeks) HBIg prophylaxis after LT followed by the long-term administration of HBV polymerase inhibitors prevents HBV recurrence. In hepatitis D virus (HDV)/HBV co-infected patients, the need for long-term HBIg prophylaxis on top of HBV polymerase inhibitors is unknown. HDV requires HBV surface antigen (HBsAg) for uptake into hepatocytes to subsequently establish HDV replication. Data on HDV recurrence and its impact on outcomes after LT are limited. In this review, we evaluated the available data on post-LT recurrence of HBV and/or HDV. Overall, HBIg prophylaxis was effective, but 10-13% of patients became HBsAg positive after LT. Only a single study from Turkey reported HDV recurrence, which was not observed in other LT centres. Since all studies administered continuous HBIg prophylaxis, the post-LT recurrence rates without HBIg prophylaxis remain unknown. In a German study, the clinical course and histopathological aspects of liver injury (inflammation, fibrosis and steatosis) were similar in post-LT patients on continuous HBIg and those who stopped HBIg after a median of 72 months. Discontinuation of HBIg in stable patients after LT for HBV/HDV co-infection did not lead to impaired overall survival or a higher recurrence rate in this long-term follow-up. In summary, discontinuation of HBIg after liver transplantation for HBV/HDV liver disease seems safe, but randomized controlled studies are needed before it can be generally recommended.

Successful clinical and virological outcomes of liver transplantation for HDV/HBV-related disease after long-term discontinuation of hepatitis B immunoglobulins

BACKGROUND

Indefinite, long-term administration of hepatitis B immunoglobulins (HBIg), together with a third generation nucleos(t)ide analog (NA), is the currently recommended prophylactic strategy to prevent viral recurrence after liver transplantation (LT) for Hepatitis Delta virus (HDV)/Hepatitis B virus (HBV)-related disease.

METHODS

We retrospectively analyzed the safety and long-term clinical and virological outcomes of a consecutive cohort of 16 patients (10 males, median age 64.5, range 41-75) transplanted for HDV/HBV-related cirrhosis at our Institution, who discontinued HBIg after a median of 24.5 months (range 15-116) after transplant. All patients continued prophylaxis with same NA used before LT. Recurrence of HDV/HBV infection was defined as reappearance of serum HDV-RNA with detectable serum HBsAg and/or HBV-DNA.

RESULTS

The median follow-up after LT was 138 months (range 73-316) and 110 months (range 52-200) after HBIg withdrawal. All patients were HBsAg-positive, HBV-DNA negative, and anti-HDV positive at the time of LT and without coinfections with HCV or HIV. Patients were followed with biochemical and virological tests every 3-6 months after HBIg withdrawal. No recurrences of HDV/HBV infection or disease were observed during monoprophylaxis with NA. In addition, eight patients (50%) spontaneously developed anti-HBs titers above 10 IU/L at a median of 74 months (range 58-140) following HBIG discontinuation.

CONCLUSIONS

HBIg withdrawal after LT is a safe and efficacious strategy in patients transplanted for HDV/HBV disease and is frequently associated with the spontaneous development of serological immunity against HBV. These data call for a revision of current prophylactic recommendations in this setting.

Epidemiology, presentation, and therapeutic approaches for hepatitis D infections

INTRODUCTION

Chronic Hepatitis D virus (HDV) infection remains an important global public health problem, with a changing epidemiological landscape over the past decade along with widespread implementation of hepatitis B vaccination and human migration. The landscape of HDV treatments has been changing, with therapies that have been under development for the last decade now in late stage clinical trials. The anticipated availability of these new therapies will hopefully replace the current therapies which are minimally effective.

AREAS COVERED

This narrative review discusses the clinical course, screening and diagnosis, transmission risk factors, epidemiology, current and investigational therapies, and liver transplantation in HDV. Literature review was performed using PubMed and ClinicalTrials.gov and includes relevant articles from 1977 to 2022.

EXPERT OPINION

HDV infection is an important global public health issue with a true prevalence that is still unknown. The distribution of HDV infection has changed globally with the availability of HBV vaccination and patterns of human migration. As HDV infection is associated with accelerated disease courses and poor outcomes, the global community needs to agree upon a uniform HDV screening strategy to understand the truth of global prevalence such that new therapies can target appropriate individuals as they become available in the future.