What Is Hepatitis D Infection?

This JAMA Patient Page describes hepatitis D infection and its risk factors, outcomes of acute and chronic infection, diagnosis, treatment, and prevention.

Blocking viral entry with bulevirtide reduces the number of HDV-infected hepatocytes in human liver biopsies.

BACKGROUND & AIMS: Bulevirtide (BLV) is a first-in-class entry inhibitor and the only approved treatment for patients chronically infected with HDV in Europe. We aimed to investigate the efficacy of BLV treatment in paired liver biopsies obtained at baseline and after 24 or 48 weeks of treatment. METHODS: We performed a combined analysis of 126 paired liver biopsies derived from three clinical trials. In the phase II clinical trial MYR202, patients with chronic hepatitis D were randomised to receive 24 weeks of BLV at 2 mg, 5 mg or 10 mg/day. Patients in MYR203 (phase II) and MYR301 (phase III) received 48 weeks of BLV at 2 mg or 10 mg/day. Tenofovir disoproxil fumarate monotherapy or delayed treatment served as comparators. Virological parameters and infection-related host genes were assessed by qPCR and immunohistochemistry. RESULTS: At week 24, median intrahepatic HDV RNA decline from baseline was 0.9Log10 with 2 mg (n = 7), 1.1Log10 with 5 mg (n = 5) and 1.4 Log10 with 10 mg (n = 7) of BLV. At week 48, median reductions were 2.2Log10 with 2 mg (n = 27) and 2.7Log10 with 10 mg (n = 37) of BLV, while HDV RNA levels did not change in the comparator arms. Notably, a drastic decline in the number of hepatitis delta antigen-positive hepatocytes and a concomitant decrease in transcriptional levels of inflammatory chemokines and interferon-stimulated genes was determined in all BLV-treatment arms. Despite the abundance of HBsAg-positive hepatocytes, replication and covalently closed circular DNA levels of the helper virus HBV were low and remained unaffected by BLV treatment. CONCLUSION: Blocking viral entry diminishes signs of liver inflammation and promotes a strong reduction of HDV infection within the liver, thus suggesting that some patients may achieve HDV cure with long-term treatment. IMPACT AND IMPLICATIONS: Chronic infection with HDV causes the most severe form of viral hepatitis, affecting approximately 12 million people worldwide. The entry inhibitor bulevirtide (BLV) is the only recently approved anti-HDV drug, which has proven efficacious and safe in clinical trials and real-word data. Here, we investigated paired liver biopsies at baseline and after 24 or 48 weeks of treatment from three clinical trials to understand the effect of the drug on viral and host parameters in the liver, the site of viral replication. We found that BLV treatment strongly reduces the number of HDV-infected cells and signs of liver inflammation. This data implies that blocking viral entry ameliorates liver inflammation and that prolonged treatment regimens might lead to HDV cure in some patients. This concept will guide the further development of therapeutic strategies and combination treatments for patients with CHD. CLINICAL TRIAL NUMBERS: NCT03546621, NCT02888106, NCT03852719.

Liver stiffness measurement as a noninvasive method for the diagnosis of liver cirrhosis in patients with chronic hepatitis D virus infection.

BACKGROUND: Noninvasive tests (NITs) have been proposed as an alternative to liver biopsy for diagnosing liver cirrhosis. The evidence of NIT performance in patients with chronic hepatitis D (CHD) is limited. AIMS: To evaluate the diagnostic performance of liver stiffness measurement (LSM) and other NITs in CHD patients. METHODS: We evaluated the diagnostic performance of LSM by transient elastography for the detection of liver cirrhosis in a retrospective, multicentre cohort of 144 CHD patients with paired (±6 months) LSM and liver biopsies. RESULTS: Cirrhosis was diagnosed histologically in 22 patients (15.3%). Mean LSM was significantly higher in patients with cirrhosis compared to those without fibrosis (23.4 vs 10.2 kPa, p < 0.0001) or with intermediate fibrosis (23.4 vs 13.5 kPa, p < 0.0001). In the detection of liver cirrhosis, LSM was superior to other NITs (AUROCs: 0.89 [LSM], 0.87 [D4FS], 0.74 [APRI], 0.73 [FIB-4], and 0.69 [AAR]). The optimal cut-off for identifying patients with liver cirrhosis was ≥15.2 kPa (Se 91%, Sp 84%, PPV 50%, NPV 98%). The ideal cut-off for diagnosing non-advanced liver fibrosis (Metavir ≤2) was <10.2 kPa (Se 55%, Sp 86%, PPV 90%, NPV 45%), correctly identifying 90% of patients. Data were validated in an independent cohort of 132 CHD patients. CONCLUSIONS: LSM is a useful tool for identifying patients at risk for liver cirrhosis and is superior to other NITs. The cut-offs of <10.2 and < 15.2 kPa reliably diagnose non-advanced liver fibrosis and exclude cirrhosis in the majority of patients. However, LSM cannot completely replace liver biopsy in CHD patients.

JAK1 promotes HDV replication and is a potential target for antiviral therapy.

BACKGROUND & AIMS: Chronic co-infection with HBV and HDV leads to the most aggressive form of chronic viral hepatitis. To date, no treatment induces efficient viral clearance, and a better characterization of virus-host interactions is required to develop new therapeutic strategies. METHODS: Using loss-of-function strategies, we validated the unexpected proviral activity of Janus kinase 1 (JAK1) - a key player in innate immunity - in the HDV life cycle and determined its mechanism of action on HDV through various functional analyses including co-immunoprecipitation assays. RESULTS: We confirmed the key role of JAK1 kinase activity in HDV infection. Moreover, our results suggest that JAK1 inhibition is associated with a modulation of ERK1/2 activation and S-HDAg phosphorylation, which is crucial for viral replication. Finally, we showed that FDA-approved JAK1-specific inhibitors are efficient antivirals in relevant in vitro models including primary human hepatocytes. CONCLUSIONS: Taken together, we uncovered JAK1 as a key host factor for HDV replication and a potential target for new antiviral treatment. IMPACT AND IMPLICATIONS: Chronic hepatitis D is the most aggressive form of chronic viral hepatitis. As no curative treatment is currently available, new therapeutic strategies based on host-targeting agents are urgently needed. Here, using loss-of-function strategies, we uncover an unexpected interaction between JAK1, a major player in the innate antiviral response, and HDV infection. We demonstrated that JAK1 kinase activity is crucial for both the phosphorylation of the delta antigen and the replication of the virus. By demonstrating the antiviral potential of several FDA-approved JAK1 inhibitors, our results could pave the way for the development of innovative therapeutic strategies to tackle this global health threat.

Molecular genetic association of rs8099917 and rs1800795 polymorphisms in the progression of hepatitis Delta virus liver disease

Background: The relationship between viral infections and host factors holds high hopes for identifying the role of Interferon Lambda 3 (IFNL3) and Interleukin 6 (IL-6) polymorphisms in the development of Chronic Liver Disease (CLD) in patients infected with hepatitis Delta virus (HDV) in the Western Brazilian Amazon. Methods: Cross-sectional study conducted with a cohort of 40 chronic HDV patients, 27 with CLD and 13 without evident liver damage. Biological samples from the participants were analyzed using the polymerase chain reaction (PCR) technique, followed by sequencing by the automated Sanger method. Results: The rs8099917 T allele, from the IFNL3 gene, showed a higher frequency in both groups; however, it was not possible to establish an association with HDV infection [OR = 1.42 (0.42 - 4.75; p = 0.556 (95% CI). For IL-6, the rs1800795 G allele was superior to rs1800795 C. Analyzing both distributions in the studied groups, any association with HDV was absent (p > 0.05). Conclusion: The results suggest that the rs8099917 T/G (IFNL3) and rs1800795 G/C (IL-6) polymorphisms are not associated with the evolution of HDV in the studied population.

Hepatitis D: A Review.

Importance: Hepatitis D virus (HDV) infection occurs in association with hepatitis B virus (HBV) infection and affects approximately 12 million to 72 million people worldwide. HDV causes more rapid progression to cirrhosis and higher rates of hepatocellular carcinoma than HBV alone or hepatitis C virus. Observations: HDV requires HBV to enter hepatocytes and to assemble and secrete new virions. Acute HDV-HBV coinfection is followed by clearance of both viruses in approximately 95% of people, whereas HDV superinfection in an HBV-infected person results in chronic HDV-HBV infection in more than 90% of infected patients. Chronic hepatitis D causes more rapidly progressive liver disease than HBV alone. Approximately 30% to 70% of patients with chronic hepatitis D have cirrhosis at diagnosis and more than 50% die of liver disease within 10 years of diagnosis. However, recent studies suggested that progression is variable and that more than 50% of people may have an indolent course. Only approximately 20% to 50% of people infected by hepatitis D have been diagnosed due to lack of awareness and limited access to reliable diagnostic tests for the HDV antibody and HDV RNA. The HBV vaccine prevents HDV infection by preventing HBV infection, but no vaccines are available to protect those with established HBV infection against HDV. Interferon alfa inhibits HDV replication and reduces the incidence of liver-related events such as liver decompensation, hepatocellular carcinoma, liver transplant, or mortality from 8.5% per year to 3.3% per year. Adverse effects from interferon alfa such as fatigue, depression, and bone marrow suppression are common. HBV nucleos(t)ide analogues, such as entecavir or tenofovir, are ineffective against HDV. Phase 3 randomized clinical trials of bulevirtide, which blocks entry of HDV into hepatocytes, and lonafarnib, which interferes with HDV assembly, showed that compared with placebo or observation, these therapies attained virological and biochemical response in up to 56% of patients after 96 weeks of bulevirtide monotherapy and 19% after 48 weeks of lonafarnib, ritonavir, and pegylated interferon alfa treatment. Conclusions and Relevance: HDV infection affects approximately 12 million to 72 million people worldwide and is associated with more rapid progression to cirrhosis and liver failure and higher rates of hepatocellular carcinoma than infection with HBV alone. Bulevirtide was recently approved for HDV in Europe, whereas pegylated interferon alfa is the only treatment available in most countries.

The Circulating miRNA Profile of Chronic Hepatitis D and B Patients Is Comparable but Differs from That of Individuals with HBeAg-Negative HBV Infection.

miRNAs circulating in whole serum and HBsAg-particles are differentially expressed in chronic hepatitis B (CHB) and HBeAg-negative-HBV infection (ENI); their profiles are unknown in chronic hepatitis D (CHD). Serum- and HBsAg-associated miRNAs were analyzed in 75 subjects of 3 well-characterized groups (CHB 25, CHD 25, ENI 25) using next-generation sequencing (NGS). Overall miRNA profiles were consonant in serum and HBsAg-particles but significantly different according to the presence of hepatitis independently of Hepatitis D Virus (HDV)-co-infection. Stringent (Bonferroni Correction < 0.001) differential expression analysis showed 39 miRNAs upregulated in CHB vs. ENI and 31 of them also in CHD vs. ENI. miRNA profiles were coincident in CHB and CHD with only miR-200a-3p upregulated in CHB. Three miRNAs (miR-625-3p, miR-142-5p, and miR-223-3p) involved in immune response were upregulated in ENI. All 3 hepatocellular miRNAs of MiR-B-Index (miR-122-5p, miR-99a-5p, miR-192-5p) were overexpressed in both CHB and CHD patients. In conclusion, CHD and CHB patients showed highly similar serum miRNA profiling that was significantly different from that of individuals with HBeAg-negative infection and without liver disease.

What is the Path Forward to Treat Hepatitis Delta Virus?: Old Treatments and New Options.

HDV use the cell enzymes for its own replication, and the HBsAg as an envelope. There is an urgent need to develop new drugs for chronic hepatitis D (CHD). Pegylated interferon alpha (PEG-IFNα) (direct-antiviral and immune modulator) has been used and recommended by scientific guidelines, although not approved, with moderate efficacy and poor tolerability. There are several drugs in development which target the host: bulevirtide (BLV), lonafarnib (LNF), nucleic acid polymer, and others.

Comparative effectiveness of seven interventions for chronic hepatitis D: a systematic review and network meta-analysis of randomized controlled trials.

OBJECTIVE: To compare the effectiveness of seven major interventions [Bulevirtide (BLV), Interferon (IFN), Nucleoside analogs (NAs), BLV + IFN, BLV + NAs, IFN + NAs, and Placebo] to treat chronic hepatitis D. METHODS: We followed PRISMA-NMA guidelines, searched databases (Cochrane Library, PubMed, EMBASE, and Web Of Science) for eligible randomized controlled trials (RCTs), and applied STATA17.0 software to execute the meta-analysis. RESULTS: We included 14 randomized controlled trials (814 patients) comparing seven different interventions. The results of the network meta-analysis showed that: ① Sustained virological response (after 24 weeks of follow-up): Four intervention groups (BLV + IFN, IFN alone, IFN + NAs, and NAs alone) were effective (relative risk (RR) = 13.30, 95% confidence interval (Cl) [1.68,105.32], RR = 12.13, 95% Cl [1.46,101.04], RR = 5.05, 95% Cl [1.68,15.19], RR = 5.03, 95% Cl [1.66,15.20]), with no statistically significant differences between the four groups. The top three in probability rankings were: BLV + NAs, BLV + IFN, and BLV alone (surface under the cumulative ranking curve (SUCRA) = 86.8%, 80.3%, and 48.4%; ② Sustained biochemical response (after 24 weeks of follow-up): BLV + IFN and IFN were superior to BLV (RR = 14.71, 95% Cl [1.14,189.07], RR = 16.67, 95% Cl [1.39,199.52]). The top three were BLV alone, BLV + NAs, and BLV + IFN (SUCRA = 86.9%,81.2%, and 64.3%). ③ Histological response: NAs were superior to BLV (RR = 2.08, 95% Cl [1.10,3.93]), whereas the difference between other treatment regimens was not statistically significant, and the top three in the probability ranking were BLV alone, BLV + NAs, and BLV + IFN (SUCRA = 75.6%, 75.6%, and 61.8%). CONCLUSIONS: IFN, IFN + BLV, and IFN + NAs were effective in clearing HDV RNA and normalizing alanine aminotransferase levels; however, IFN and IFN + NAs had a high rate of viral relapse at 24 weeks post-treatment follow-up. There was no additional benefit of adding NAs to IFN therapy for chronic hepatitis D; however, the combination of IFN + BLV significantly improved short-term HDV RNA clearance, which showed strong synergistic effects. The seven regimens included in the study did not contribute significantly to liver histological improvement. Therefore, the IFN + BLV combination has the most potential as a treatment option to improve the long-term prognosis or even cure chronic hepatitis D. TRIAL REGISTRATION: This systematic evaluation and meta-analysis was registered with PROSPERO under the registration number: CRD42022314544.).

A Phase 3, Randomized Trial of Bulevirtide in Chronic Hepatitis D.

BACKGROUND: Coinfection with hepatitis D virus (HDV) accelerates the progression of liver disease associated with chronic hepatitis B. Bulevirtide inhibits the entry of HDV into hepatocytes. METHODS: In this ongoing phase 3 trial, patients with chronic hepatitis D, with or without compensated cirrhosis, were randomly assigned, in a 1:1:1 ratio, to receive bulevirtide subcutaneously at 2 mg per day (2-mg group) or 10 mg per day (10-mg group) for 144 weeks or to receive no treatment for 48 weeks followed by bulevirtide subcutaneously at 10 mg per day for 96 weeks (control group). Patients will complete 96 weeks of additional follow-up after the end of treatment. The primary end point was a combined response at week 48 of an undetectable HDV RNA level, or a level that decreased by at least 2 log10 IU per milliliter from baseline, and normalization of the alanine aminotransferase (ALT) level. The key secondary end point was an undetectable HDV RNA level at week 48, in a comparison between the 2-mg group and the 10-mg group. RESULTS: A total of 49 patients were assigned to the 2-mg group, 50 to the 10-mg group, and 51 to the control group. A primary end-point response occurred in 45% of patients in the 2-mg group, 48% in the 10-mg group, and 2% in the control group (P<0.001 for the comparison of each dose group with the control group). The HDV RNA level at week 48 was undetectable in 12% of patients in the 2-mg group and in 20% in the 10-mg group (P = 0.41). The ALT level normalized in 12% of patients in the control group, 51% in the 2-mg group (difference from control, 39 percentage points [95% confidence interval {CI}, 20 to 56]), and 56% in the 10-mg group (difference from control, 44 percentage points [95% CI, 26 to 60]). Loss of hepatitis B virus surface antigen (HBsAg) or an HBsAg level that decreased by at least 1 log10 IU per milliliter did not occur in the bulevirtide groups by week 48. Headache, pruritus, fatigue, eosinophilia, injection-site reactions, upper abdominal pain, arthralgia, and asthenia were more common in the 2-mg and 10-mg groups combined than in the control group. No treatment-related serious adverse events occurred. Dose-dependent increases in bile acid levels were noted in the 2-mg and 10-mg groups. CONCLUSIONS: After 48 weeks of bulevirtide treatment, HDV RNA and ALT levels were reduced in patients with chronic hepatitis D. (Funded by Gilead Sciences; MYR 301 ClinicalTrials.gov number, NCT03852719.).

Chronic hepatitis delta cirrhosis cured by adapting PEG-IFNα-2a + tenofovir disoproxil fumarate treatment duration until HBsAg loss.

As the loss of HBsAg during treatment of chronic hepatitis delta (CHD) is mandatory for definitive clearance and durable response, the optimal target of therapy should be complete response (CR), defined as loss of HDV RNA and HBsAg, plus development of anti-HBs. The optimal treatment duration of CHD is not well established. We present 2 cases of patients with CHD cirrhosis who were treated with prolonged Peg-IFNα-2a + tenofovir disoproxil fumarate until HBsAg loss, and who achieved CR after 46 and 55 months of treatment respectively. A personalized approach and prolonged treatment duration determined by HBsAg loss may increase the likelihood of CR in CHD.