Hepatitis Delta Infection: A Clinical Review

Abstract

First discovered over 40 years ago, the hepatitis delta virus (HDV) is a unique RNA virus, requiring hepatitis B virus (HBV) antigens for its assembly, replication, and transmission. HBV and HDV can be acquired at the same time (coinfection) or HDV infection can occur in persons with chronic HBV (superinfection). Screening guidelines for HDV are inconsistent. While some guidelines recommend universal screening for all people with HBV, others recommend risk-based screening. Estimates of the global HDV prevalence range from 4.5% to 14.6% among persons with HBV; thus, there may be up to 72 million individuals with HDV worldwide. HDV is the most severe form of viral hepatitis. Compared to HBV monoinfection, HDV coinfection increases the risk of cirrhosis, hepatocellular carcinoma, hepatic decompensation, mortality, and necessity for liver transplant. Despite the severity of HDV, there are few treatment options. Pegylated interferon (off-label use) has long been the only available treatment, although bulevirtide is conditionally approved in some European countries. There are many potential treatments in development, but as yet, there are few effective and safe therapies for HDV infection. In conclusion, given the severity of HDV disease and the paucity of treatments, there is a great unmet need for HDV therapies.

Clinical outcomes of treatment-naïve HBeAg-negative patients with chronic hepatitis B virus infection with low serum HBsAg and undetectable HBV DNA

“…We did not detect the HBsAg-specific T cell and HBsAg-specific B cell responses due to the retrospective nature and the lack of blood samples of these patients. Last, coinfection of hepatitis D virus (HDV) in patients with CHB is associated with more severe hepatitis and an increased risk of disease progression [ 36 , 37 ]. However, screening for HDV is rarely performed in reality [ 37–39 ].…”

Highlights from the 2023 International Meeting on the Molecular Biology of Hepatitis B virus

“…A breakthrough for the treatment of HDV was the approval of bulevirtide (BLV) (also known at Myrcludex B or hepcludex) [30] in some countries. BLV is derived from the myristoylated preS1 sequence (amino acids 1–48) and targets NTCP and blocks its interaction with HBV or HDV.…”

Letter: Association between aspirin use and risk of hepatocellular carcinoma in patients with chronic hepatitis B

“…an estimated prevalence range of 4.5% to 14.6% in HBV-infected patients. 4 Several studies have demonstrated a significantly increased risk of HCC in patients with chronic HDV infection compared to those with HBV mono-infection. [3][4][5] However, co-infection with HDV was not mentioned and excluded, which might impact the results.…”