Meta-analysis: antiviral treatment for hepatitis D

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.).

Australian consensus recommendations for the management of hepatitis B

INTRODUCTION

The prevalence of hepatitis B virus (HBV) infection in Australia is nearly 1%. In certain well defined groups the prevalence is far greater, yet an estimated 27% of people living with HBV infection remain undiagnosed. Appropriate screening improves detection, increases opportunity for treatment, and ultimately reduces the significant morbidity and mortality associated with the development of liver fibrosis and hepatocellular carcinoma (HCC).

MAIN RECOMMENDATIONS

This statement highlights important aspects of HBV infection management in Australia. There have been recent changes in nomenclature and understanding of natural history, as well as a newly defined upper limit of normal for liver tests that determine phase classification and threshold for antiviral treatment. As the main burden of hepatitis B in Australia is within migrant and Indigenous communities, early identification and management of people living with hepatitis B is essential to prevent adverse outcomes including liver cancer and cirrhosis.

CHANGE IN MANAGEMENT AS A RESULT OF THIS GUIDELINE

These recommendations aim to raise awareness of the current management of hepatitis B in Australia. Critically, the timely identification of individuals living with hepatitis B, and where appropriate, commencement of antiviral therapy, can prevent the development of cirrhosis, HCC and mother-to-child transmission as well as hepatitis B reactivation in immunocompromised individuals. Recognising patient and viral factors that predispose to the development of cirrhosis and HCC will enable clinicians to risk-stratify and appropriately implement surveillance strategies to prevent these complications of hepatitis B.

Viral hepatitis: Innovations and expectations

Viral hepatitis is a significant health problem worldwide, associated with morbidity and mortality. Hepatitis B, C, D, and occasionally E viruses (HBV, HCV, HDV, and HEV) can evolve in chronic infections, whereas hepatitis A virus (HAV) frequently produces acute self-limiting hepatitis. In the last years, different studies have been performed to introduce new antiviral therapies. The most important goal in the treatment of viral hepatitis is to avoid chronic liver disease and complications. This review analyzes currently available therapies, in particular for viruses associated with chronic liver disease. The focus is especially on HBV and HCV therapies, investigating new drugs already introduced in clinical practice and clinical trials. We also describe new entry inhibitors, developed for the treatment of chronic HDV and HBV and currently available treatments for HEV. The last drugs introduced have shown important efficacy in HCV, with achievable target HCV elimination by 2030. Concurrently, renewed interest in curative HBV therapies has been registered; current nucleotide/ nucleoside analogs positively impact liver-related complications, ensuring high safety and tolerability. Novel approaches to HBV cure are based on new antivirals, targeting different steps of the HBV life cycle and immune modulators. The improved knowledge of the HDV life cycle has facilitated the development of some direct-acting agents, as bulevirtide, the first drug conditionally approved in Europe for HDV associated compensated liver disease. Further studies are required to identify a new therapeutic approach in hepatitis E, especially in immunosuppressed patients.

HBV and HDV: New Treatments on the Horizon

Despite the accumulating knowledge, chronic hepatitis B (CHB) and HDV infection represent a global health problem, and there are still several critical issues, which frequently remain uncovered. In this paper, we provided an overview of the current therapeutic options and summarized the investigational therapies in the pipeline. Furthermore, we discussed some critical issues such as a “functional cure” approach, the futility of long-term NA therapy and the relevance of understanding drug actions and safety of antivirals, especially in special populations.

Chronic hepatitis D associated with worse patient-reported outcomes than chronic hepatitis B

BACKGROUND & AIMS

Health-related quality of life (HRQoL) determined by patient-reported outcomes (PROs) is impaired in chronic hepatitis B (CHB) and C patients, but there are no data regarding patients with chronic hepatitis D (CHD). The aim of this study was to assess PRO scores in untreated patients with CHD and compare them with those obtained for patients with CHB.

METHODS

Patients with CHD completed 3 PRO instruments (Chronic Liver Disease Questionnaire [CLDQ], Functional Assessment of Chronic Illness Therapy-Fatigue [FACIT-F], and Work Productivity and Activity Impairment [WPAI]), and the results were compared with those of patients mono-infected with CHB.

RESULTS

In total, 125 patients were included: 43 with CHD and 82 with CHB. Overall, baseline PROs showed differences between both groups. Several assessments, such as the worry score from CLDQ (p = 0.0118), functional well-being from FACIT-F (p = 0.0281), and activity impairment from WPAI (p = 0.0029) showed a significant trend to worse scores in patients with CHD than with CHB. In addition, the linear regression model supports the finding that having CHD as opposed to having CHB was a predictor of a higher worry score (CLDQ) and a higher activity impairment (WPAI).

CONCLUSIONS

In this first assessment in CHD, PROs recorded in patients with CHD showed a significant impairment in some domains of HRQoL questionnaires in comparison with those with CHB. Studies in larger cohorts with lengthier follow-up are needed to fully assess patient-reported quality of life over the course of CHD.

LAY SUMMARY

Chronic hepatitis D (CHD) is a viral disease that causes rapid evolution to liver cirrhosis, amongst other severe complications, when compared to patients with chronic hepatitis B (CHB). Health-related quality of life in chronic hepatitis C and CHB has been reported widely, but no studies have been performed on patient-reported outcomes in patients with CHD. Results showed that CHD patients reported worse outcomes in psychological domains such as worry and emotional well-being, as well as in physical domains such as abdominal symptoms, physical well-being, and activity impairment in comparison with patients with CHB.

The changing context of hepatitis D

The global epidemiology of hepatitis D is changing with the widespread implementation of vaccination against hepatitis B. In high-income countries that achieved optimal control of HBV, the epidemiology of hepatitis D is dual, consisting of an ageing cohort of domestic patients with advanced liver fibrosis who represent the end stage of the natural history of HDV, and of a younger generation of immigrants from endemic countries who account for the majority of new infections. As observed in Europe in the 1980s, the distinctive clinical characteristic of chronic hepatitis D in endemic countries is the accelerated progression to cirrhosis and hepatocellular carcinoma. Despite some recent progress, the therapeutic management of HDV remains unsatisfactory, as most patients are not cured of HDV with currently available medicines. This review article describes the current epidemiology and clinical features of chronic hepatitis D, based on the literature published in the last 10 years.

New insights into HDV persistence: The role of interferon response and implications for upcoming novel therapies

Chronic hepatitis D (CHD), a global health problem, manifests as the most severe form of viral hepatitis. The causative agent, HDV, is the smallest known human virus; it replicates its circular single-stranded RNA genome in the nucleus of hepatocytes. HDV requires HBV-encoded envelope proteins for dissemination and de novo cell entry. However, HDV can also spread through cell division. Following entry into hepatocytes, replicative intermediates of HDV RNA are sensed by the pattern recognition receptor MDA5 (melanoma differentiation antigen 5) resulting in interferon (IFN)-β/λ induction. This IFN response strongly suppresses cell division-mediated spread of HDV genomes, however, it only marginally affects HDV RNA replication in already infected, resting hepatocytes. Monotherapy with IFN-α/λ shows efficacy but rarely results in HDV clearance. Recent molecular insights into key determinants of HDV persistence and the accelerated development of specifically acting antivirals that interfere with the replication cycle have revealed promising new therapeutic perspectives. In this review, we briefly summarise our knowledge on replication/persistence of HDV, the newly discovered HDV-like agents, and the interplay of HDV with the IFN response and its consequences for persistence. Finally, we discuss the possible role of IFNs in combination with upcoming therapies aimed at HDV cure.

Interplay between Hepatitis D Virus and the Interferon Response

Chronic hepatitis D (CHD) is the most severe form of viral hepatitis, with rapid progression of liver-related diseases and high rates of development of hepatocellular carcinoma. The causative agent, hepatitis D virus (HDV), contains a small (approximately 1.7 kb) highly self-pairing single-strand circular RNA genome that assembles with the HDV antigen to form a ribonucleoprotein (RNP) complex. HDV depends on hepatitis B virus (HBV) envelope proteins for envelopment and de novo hepatocyte entry; however, its intracellular RNA replication is autonomous. In addition, HDV can amplify HBV independently through cell division. Cellular innate immune responses, mainly interferon (IFN) response, are crucial for controlling invading viruses, while viruses counteract these responses to favor their propagation. In contrast to HBV, HDV activates profound IFN response through the melanoma differentiation antigen 5 (MDA5) pathway. This cellular response efficiently suppresses cell-division-mediated HDV spread and, to some extent, early stages of HDV de novo infection, but only marginally impairs RNA replication in resting hepatocytes. In this review, we summarize the current knowledge on HDV structure, replication, and persistence and subsequently focus on the interplay between HDV and IFN response, including IFN activation, sensing, antiviral effects, and viral countermeasures. Finally, we discuss crosstalk with HBV.

‘Double-hit’ pegylated interferon-alpha successfully treats Hepatitis B and Hepatitis D co-infection

Hepatitis delta (HDV) infection is either acquired simultaneously with, or as a superinfection to, existing Hepatitis B (HBV). It leads to a serious form of chronic viral hepatitis and accelerated liver-related morbidity and mortality including hepatocellular carcinoma. Current treatment regimes propose Pegylated interferon-alpha for 48 weeks however sustained virological response (SVR) rates remain low. We report a patient who initially responded to Pegylated interferon treatment for HBV-HDV co-infection. Although initial improvement in viraemia from both virsues was seen, SVR was not achieved with ongoing progression of liver injury biochemically. However, the summative effect of a second course of Pegylated interferon 2 years later led to HDV cure (SVR 12 months post-treatment), very low level HBV carrier status (with persistently undetectable viral load) and ongoing biochemical normalization. This case illustrates a successful treatment strategy for persistent HBV-HDV co-infection where proposed treatment regimes elicit an initial response but SVR is not achieved.

Asian consensus recommendations on optimizing the diagnosis and initiation of treatment of hepatitis B virus infection in resource-limited settings

Asia has an intermediate-to-high prevalence of and high morbidity and mortality from hepatitis B virus (HBV) infection. Optimization of diagnosis and initiation of treatment is one of the crucial strategies for lowering disease burden in this region. Therefore, a panel of 24 experts from 10 Asian countries convened, and reviewed the literature, to develop consensus guidance on diagnosis and initiation of treatment of HBV infection in resource-limited Asian settings. The panel proposed 11 recommendations related to diagnosis, pre-treatment assessment, and indications of therapy of HBV infection, and management of HBV-infected patients with co-infections. In resource-limited Asian settings, testing for hepatitis B surface antigen may be considered as the primary test for diagnosis of HBV infection. Pre-treatment assessments should include tests for complete blood count, liver and renal function, hepatitis B e-antigen (HBeAg), anti-HBe, HBV DNA, co-infection markers and assessment of severity of liver disease. Noninvasive tests such as AST-to-platelet ratio index, fibrosis score 4 or transient elastography may be used as alternatives to liver biopsy for assessing disease severity. Considering the high burden of HBV infection in Asia, the panel adopted an aggressive approach, and recommended initiation of antiviral therapy in all HBV-infected, compensated or decompensated cirrhotic individuals with detectable HBV DNA levels, regardless of HBeAg status or alanine transaminase levels. The panel also developed a simple algorithm for guiding the initiation of treatment in noncirrhotic, HBV-infected individuals. The recommendations proposed herein, may help guide clinicians, to optimize the diagnosis and improvise the treatment rates for HBV infection in Asia.

Treatment of hepatitis D: an unmet medical need

BACKGROUND

Therapy of chronic hepatitis D (CHD) is still based on interferon alpha (IFNα), introduced in clinical practice 30 years ago: results are modest and better therapies are an urgent medical need.

AIMS

This article provides a critical overview of the new therapies under investigation for CHD.

SOURCES

Review of the recently published medical literature.

CONTENT

New therapeutic efforts aim to deprive the hepatitis D virus (HDV) of functions provided to its life cycle by the hepatitis B Virus (HBV) or by the host. Three therapeutic strategies are in evaluation: a) Myrcludex B, a myristolated lipopeptide of the pre-S1 domain of the HBsAg that blocks the entry of the HDV into hepatocyes and controls infection by preventing the spreading of the virus to liver cells not infected by the HBV; b) Lonafarnib, an inhibitor of a host farnesyl-transferase that hinders morphogenesis of the HDV by preventing the farnesylation of the large HD-antigen, necessary for virion assembly; c) REP 2139, a nucleic acid polymer that prevents export of the mature HDV by the presumed inhibition of the synthesis of subviral HBsAg particles with which the virion is coated. Myrcludex B and Lonafarnib increase therapeutic efficacy in combination with Peg-IFNα. In a pilot study, REP 2139 in combination with Peg-IFNα induced the clearance of serum HDV RNA and of the HBsAg in about half of 12 treated patients.

IMPLICATIONS

Long-term therapies with either Myrcludex B or Lonafarnib in combination with Peg-IFNα are required to achieve clinical control of CHD. However, with prolonged therapies tolerance becomes a problem; studies are on the way to determine whether Peg-IFN lambda may be better tolerated that Peg-IFNα. The promising preliminary data of REP 2139 in combination with Peg-IFNα await confirmation of the original pilot study.

Long-term clinical outcomes in patients with chronic hepatitis delta: the role of persistent viraemia

BACKGROUND

Chronic hepatitis delta is a severe liver disease with rapid progression to cirrhosis. The impact of hepatitis delta virus (HDV)-RNA on disease progression and interferon treatment in a real-world cohort has been barely explored.

AIM

To assess the development of clinical events in a cohort of chronic hepatitis delta patients according to the presence or absence of HDV-RNA METHODS: Multicentre study at four academic hospitals in Spain included anti-HDV-positive patients with compensated liver disease with a follow-up ≥12 months.

RESULTS

Among 2888 HBsAg-positive subjects, 151 (5.2%) tested positive for anti-HDV, and 118 were included (58% men; median age, 49 years; 73% detectable HDV-RNA and 30% cirrhosis, most often in subjects with HDV-RNA). After a median follow-up of 8 years, subjects with initially detectable HDV-RNA were more prone to developing cirrhosis (31% vs 0%, P = .002) and/or liver decompensation (28% vs 3%, P = .019). Mortality rate was 0.44 per 1000 person-months. The probability of a clinical event was 6%, 25%, and 80% according to initial baseline-event-anticipation score. HDV-RNA became undetectable in 21 (24%) subjects either due to interferon or spontaneously (48% vs 52%, P = .29). Liver decompensation was reduced in interferon-treated patients (13% vs 38%, P = .026).

CONCLUSIONS

Subjects with persistently positive HDV-RNA had a worse prognosis in terms of clinical events. Baseline-event-anticipation score is useful in predicting the risk of developing liver decompensation and hepatocellular carcinoma. Interferon was beneficial in reducing liver decompensation, even in the absence of virological response.

Clinical outcomes in patients with hepatitis D, cirrhosis and persistent hepatitis B virus replication, and receiving long-term tenofovir or entecavir

BACKGROUND

Suppression of hepatitis B virus (HBV) replication with nucelos(t)ide analogues should be considered for patients with chronic hepatitis D virus (HDV) infection and ongoing HBV replication.

AIM

To verify the clinical outcome after long-term entecavir or tenofovir treatment in patients with advanced fibrosis/cirrhosis, ineligible to peg-interferon therapy.

METHODS

Patients were prospectively followed-up at 3-6 month intervals; measured outcomes were decompensation, hepatocellular carcinoma (HCC), liver transplant and liver related death. HBV monoinfected patients receiving the same treatment served as reference after 1:1 matching by age, gender, platelet count, albumin level, bilirubin and INR.

RESULTS

56 HDV patients (48 with cirrhosis; median follow-up 50 months) were enrolled; all achieved HBV DNA suppression. Death or liver transplant occurred in 19 patients, with a rate (n/1000 patient-months) of 2.92 in HDV patients vs 0.38 in HBV monoinfected patients (P < 0.001); similarly, decompensation occurred at a rate of 1.53 vs 0.13 (P = 0.015), respectively, and the rate of HCC was almost thrice in HDV cohort (3.12 vs 1.12; P = 0.02) Platelet count, Child-Pugh score and marginally HDV infection were associated with HCC development.

CONCLUSION

Patients with HDV infection and advanced liver disease maintain an increased risk of severe clinical events as compared with HBV monoinfected patients, during prolonged HBV DNA suppression with potent NA.

Antiviral treatment with pegylated interferon and clinical outcomes in a cohort of immigrants patients affected by hepatitis delta: A retrospective analysis

Chronic hepatitis delta (CHD) is the most severe chronic hepatitis, with no satisfactory treatment options and severe clinical outcomes. This infection is frequent in the migrant subjects from endemic areas, especially from Africa and East-Europe. The pegylated (PEG)-interferon α (IFN) is limited by side effects and poor response. In this retrospective analysis, we reported our experience of treatment with PEG-IFN in a cohort of immigrant patients affected by CHD. We evaluated the virological responses are as follows: complete response (CR; clearance of hepatitis B surface antigen [HBsAg] and hepatitis D virus [HDV]-RNA), partial response (PR; HBsAg clearance with HDV-RNA+), and null response (NR; HBsAg and HDV-RNA+). Clinical outcomes were clinical stabilization, disease progression, hepatic decompensation, hepatocellular carcinoma (HCC), death, and liver transplantation. Forty-six patients were included. At the end of treatment (ET), 11 patients gained a CR (23.9%), 10 were PR (21.7%), and 16 were NR (34.8%). After 1 year, 10 remained with CR (21.7%), after 2 years, 9 (19.5%), and at 3 years, 8 (17.4%). Relapse rate was 2.2%, 4.4%, and 6.5% at year 1, 2, and 3, respectively. Favorable factors were CR at the ET (odds ratio [OR] = 4.559, 95% confidence interval [CI]: 2.219-7.116; P = 0.003), PEG-IFN course greater than 1 (OR = 1.240, 95% CI: 0.998-4.839; P = 0.012), prolonged treatment (OR = 1.276, 95% CI: 0.816-3.108; P = 0.018), quantitative hepatitis B surface antigen (qHBsAg) decline at 12 weeks greater than 0.5 log IU/mL (OR = 4.816, 95% CI: 2.190-8.194; P < 0.001). The unfavorable factors were cirrhosis (OR = 3.122, 95% CI: 1.466-4.190; P = 0.012), active hepatitis B virus (OR = 2.334, 95% CI: 1.788-3.992; P = 0.018), NR at ET (OR = 6.998, 95% CI: 5.987-11.404; P < 0001). Treatment of CHD is limited by poor virological response; is NR unfavorable outcomes were unavoidable. No other treatment options were available.

Management of Hepatitis B Virus Infection: 2018 Guidelines from the Canadian Association for the Study of Liver Disease and Association of Medical Microbiology and Infectious Disease Canada

Hepatitis B virus (HBV) infection is an important public health problem in Canada. In keeping with evolving evidence and understanding of HBV pathogenesis, the Canadian Association for the Study of Liver Disease periodically publishes HBV management guidelines. The goals of the 2018 guidelines are to (1) highlight the public health impact of HBV infection in Canada and the need to improve diagnosis and linkage to care, (2) recommend current best-practice guidelines for treatment of HBV, (3) summarize the key HBV laboratory diagnostic tests, and (4) review evidence on HBV management in special patient populations and include more detail on management of HBV in pediatric populations. An overview of novel HBV tests and therapies for HBV in development is provided to highlight the recent advances in HBV clinical research. The aim and scope of these guidelines are to serve as an up-to-date, comprehensive resource for Canadian health care providers in the management of HBV infection.

Chronic hepatitis B virus infection

Chronic hepatitis B virus infection is a global public health threat that causes considerable liver-related morbidity and mortality. It is acquired at birth or later via person-to-person transmission. Vaccination effectively prevents infection and chronic hepatitis B virus carriage. In chronically infected patients, an elevated serum hepatitis B virus DNA concentration is the main risk factor for disease progression, although there are other clinical and viral parameters that influence disease outcomes. In addition to liver biochemistry, virological markers, and abdominal ultrasonography, non-invasive assessment of liver fibrosis is emerging as an important assessment modality. Long-term nucleos(t)ide-analogue therapy is safe and well tolerated, achieves potent viral suppression, and reduces the incidence of liver-related complications. However, a need to optimise management remains. Promising novel therapies are at the developmental stage. With current vaccines, therapies, and an emphasis on improving linkage to care, WHO's goal of eliminating hepatitis B virus as a global health threat by 2030 is achievable.

EASL 2017 Clinical Practice Guidelines on the management of hepatitis B virus infection

Hepatitis B virus (HBV) infection remains a global public health problem with changing epidemiology due to several factors including vaccination policies and migration. This Clinical Practice Guideline presents updated recommendations for the optimal management of HBV infection. Chronic HBV infection can be classified into five phases: (I) HBeAg-positive chronic infection, (II) HBeAg-positive chronic hepatitis, (III) HBeAg-negative chronic infection, (IV) HBeAg-negative chronic hepatitis and (V) HBsAg-negative phase. All patients with chronic HBV infection are at increased risk of progression to cirrhosis and hepatocellular carcinoma (HCC), depending on host and viral factors. The main goal of therapy is to improve survival and quality of life by preventing disease progression, and consequently HCC development. The induction of long-term suppression of HBV replication represents the main endpoint of current treatment strategies, while HBsAg loss is an optimal endpoint. The typical indication for treatment requires HBV DNA >2,000IU/ml, elevated ALT and/or at least moderate histological lesions, while all cirrhotic patients with detectable HBV DNA should be treated. Additional indications include the prevention of mother to child transmission in pregnant women with high viremia and prevention of HBV reactivation in patients requiring immunosuppression or chemotherapy. The long-term administration of a potent nucleos(t)ide analogue with high barrier to resistance, i.e., entecavir, tenofovir disoproxil or tenofovir alafenamide, represents the treatment of choice. Pegylated interferon-alfa treatment can also be considered in mild to moderate chronic hepatitis B patients. Combination therapies are not generally recommended. All patients should be monitored for risk of disease progression and HCC. Treated patients should be monitored for therapy response and adherence. HCC remains the major concern for treated chronic hepatitis B patients. Several subgroups of patients with HBV infection require specific focus. Future treatment strategies to achieve 'cure' of disease and new biomarkers are discussed.

Investigational drugs in development for Hepatitis D

INTRODUCTION

Treatment of chronic hepatitis D still relies on Interferon. To improve efficacy, new therapeutic strategies are in development which aim to deprive the Hepatitis D Virus (HDV) of functions of the Hepatitis B Virus and of the host required for its life-cycle. Areas covered: The therapeutic options are; 1) The inhibition of the farnesylation of the large HD-protein permissive of virion assembly with Lonafarnib, 2) The blocking of HBsAg entry into cells with Myrcludex B via the inhibition of the Sodium Taurocholate Cotransporting Receptor, to prevent the spreading of HDV to uninfected hepatocytes, 3) The reduction of subviral HBsAg particles by REP 2139, leading to diminished virion morphogenesis . Expert opinion: Lonafarnib and Myrcludex reduced serum HVD-RNA; neither diminished serum HBsAg. NAP REP-2139 diminished both HDV-RNA and HBsAg in serum; a full report is awaited. In combination with Peg-Interferon, these new drugs may provide additional efficacy.

Treatment of chronic hepatitis D with the entry inhibitor myrcludex B: First results of a phase Ib/IIa study

BACKGROUND & AIMS

The therapeutic option for patients with chronic hepatitis delta virus infection (CHD) is limited to interferon alpha with rare curative outcome. Myrcludex B is a first-in-class entry inhibitor inactivating the hepatitis B virus (HBV) and hepatitis D virus (HDV) receptor sodium taurocholate co-transporting polypeptide. We report the interim results of a pilot trial on chronically infected HDV patients treated with myrcludex B, or pegylated interferon alpha (PegIFNα-2a) or their combination.

METHODS

Twenty-four patients with CHD infection were equally randomized (1:1:1) to receive myrcludex B, or PegIFNα-2a or their combination. Patients were evaluated for virological and biochemical response and tolerability of the study drugs at weeks 12 and 24.

RESULTS

Myrcludex B was well tolerated and no serious adverse event occurred. Although hepatitis B surface antigen levels remained unchanged, HDV RNA significantly declined at week 24 in all cohorts. HDV RNA became negative in two patients each in the Myrcludex B and PegIFNα-2a cohorts, and in five patients of the Myrcludex B+PegIFNα-2a cohort. ALT decreased significantly in the Myrcludex B cohort (six of eight patients), and HBV DNA was significantly reduced at week 24 in the Myrcludex B+PegIFNα-2a cohort. Virus kinetic modeling suggested a strong synergistic effect of myrcludex B and PegIFNα-2a on both HDV and HBV.

CONCLUSIONS

Myrcludex B showed a strong effect on HDV RNA serum levels and induced ALT normalization under monotherapy. Synergistic antiviral effects on HDV RNA and HBV DNA in the Myr-IFN cohort indicated a benefit of the combination of entry inhibition with PegIFNα-2a to treat CHD patients.

LAY SUMMARY

Myrcludex B is a new drug to treat hepatitis B and D infection. After 24weeks of treatment with myrcludex B and/or pegylated interferon α-2a, HDV R NA, a relevant marker for hepatitis D infection, decreased in all patients with chronic hepatitis B and D. Two of eight patients which received either myrcludex B or pegylated interferon α-2a, became negative for HDV RNA, and five of seven patients who received both drugs at the same time became negative. The drug was well tolerated.

HBsAg kinetics in chronic hepatitis D during interferon therapy: on-treatment prediction of response

BACKGROUND

Therapy of chronic hepatitis D with Interferon is successful when testing for HDV-RNA turns negative. This end-point is disputed.

AIM

To assess the role of serum hepatitis B surface antigen (HBsAg) in the clearance of HDV-RNA in pegylated interferon (Peg-IFN)-treated chronic hepatitis D (CHD).

METHODS

Sixty-two patients with CHD, treated with Peg-IFN, were considered. The patients belonged to three groups: 14 patients cleared the HBsAg and HDV-RNA (responders, R), 12 cleared the HDV-RNA remaining positive for HBsAg (partial responders, PR) and 36 cleared neither the HBsAg nor the HDV-RNA (nonresponders, NR).

RESULTS

In responders, at baseline the median value (mv) of HBsAg and HDV-RNA was 1187 and 188 663 IU/mL. By month 6 of therapy, HBsAg declined to less than 1000 IU/mL and HDV-RNA was undetectable in 12 patients. In NR, the pre-therapy median value of HBsAg and HDV viremia was 6577 and 676 319 IU/mL. There was no significant reduction of antigen at month 6; after a decline, HDV-RNA rebounded to baseline levels. In PR, the median value of baseline HBsAg was 7031 IU/mL; it declined at month 6 in the majority. HDV-RNA progressively declined from an initial median value of 171 405 IU/mL. HBsAg <1000 IU/mL at month 6 discriminated responders and PR from NR (P < 0.001). By ROC curve, the threshold of 0.105 log reduction of HBsAg associated with 1.610 log reduction of HDV-RNA from baseline to month 6 predicted the clearance of this marker.

CONCLUSIONS

A reduction of serum HBsAg is mandatory for the definitive clearance of the HDV-RNA. Quantitative HBsAg may predict the long-term response to Peg-IFN therapy and provide a guide to prolong or stop treatment.

The adventure of delta

The hepatitis D virus (HDV) is unique in animal virology. It has a circular RNA genome that is the smallest of human viruses, requires the HBsAg capsid of the hepatitis B virus to assembly into infectious virions, parasitizes the transcriptional machinery of the host by hijacking cellular RNA polymerases to replicate its RNA genome and is replicated by a rolling circle mechanism unknown to mammalian cells. Hepatitis D is ubiquitous but prevalence varies throughout the world. It is the most severe form of chronic viral liver disorder; carriers of HBsAg superinfected by the HDV are the major victims and the reservoir of the infection. In the last 20 years vaccination against the hepatitis B virus (HBV) has decreased the circulation of HDV in industrialized countries; nevertheless hepatitis D is returning to Western Europe through immigration from HDV endemic areas. Hepatitis D is being rediscovered in the developing world. It has a significant medical impact on areas of Africa, Asia and South America where the partner HBV is not controlled; Pakistan and Mongolia appear to be worldwide the areas with the highest prevalence of the disease. A major obstacle in treatment is that the virus has no replicative function of its own to be targeted by antivirals. Peg-Interferon remains the mainstay of treatment. New strategies are explored to prevent entry of the virion into hepatocytes by blocking the cellular HBsAg receptor or preventing the prenylation process of the large-delta antigen necessary for the assembly of the HDV particle.

Hepatitis delta virus: A fascinating and neglected pathogen

Hepatitis delta virus (HDV) is the etiologic agent of the most severe form of virus hepatitis in humans. Sharing some structural and functional properties with plant viroids, the HDV RNA contains a single open reading frame coding for the only virus protein, the Delta antigen. A number of unique features, including ribozyme activity, RNA editing, rolling-circle RNA replication, and redirection for a RNA template of host DNA-dependent RNA polymerase II, make this small pathogen an excellent model to study virus-cell interactions and RNA biology. Treatment options for chronic hepatitis Delta are scarce and ineffective. The disease burden is perhaps largely underestimated making the search for new, specific drugs, targets, and treatment strategies an important public health challenge. In this review we address the main features of virus structure, replication, and interaction with the host. Virus pathogenicity and current treatment options are discussed in the light of recent developments.

Chronic hepatitis B virus infection

All providers, regardless of specialty, should perform screening for HBV on high-risk persons, especially those born in endemic countries. The primary care physician can perform the initial evaluation and follow-up of patients with chronic HBV by following the algorithm in this article and consulting with specialists when appropriate. Chronically infected patients should be followed on a regular basis, preferably every 6 months, with liver function tests, and when appropriate, HBV DNA levels. Those who meet the criteria for high risk for HCC should undergo liver ultrasound every 6 months. Powerful antiviral medications are available that can suppress but not cure HBV and result in resolution of liver inflammation and fibrosis, even cirrhosis, as well as decrease the risk of developing HCC. They should be used in those patients who meet the criteria outlined in the practice guidelines of the major liver societies.

Effect of tenofovir with and without interferon on hepatitis D virus replication in HIV-hepatitis B virus-hepatitis D virus-infected patients

The effect of tenofovir (TDF) alone or in combination with interferon on hepatitis D virus (HDV) replication is poorly characterized in patients infected with human immunodeficiency virus (HIV), hepatitis B virus (HBV), and HDV. We analyzed triinfected patients undergoing treatment with either TDF alone (n=13) or including interferon (IFN) at some point during TDF therapy (TDF+IFN, n=4). Linear mixed-effect models were used to estimate the mean change from baseline of HDV-RNA and hepatitis surface antigen (HBsAg) levels during treatment. Patients were followed for a median 31.6 (25-75%-tile: 15.0-47.4) months. In the TDF+IFN group, three initiated IFN-based therapy after a median of 21.7 months (range=10.5-24.9) of lamivudine (LAM)+TDF, while the remaining patient had 46.8 months of prior LAM exposure. Significant decreases in HDV-RNA were observed in both groups [TDF alone: -0.380 log10 copies/ml per year (95% CI: -0.557, -0.202) vs. TDF+IFN: -1.325 log10 copies/ml per year (95% CI: -1.931, -0.720)], while the HDV-RNA decline overall was significantly faster in patients with TDF+IFN (p=0.002). Accordingly, two patients achieved HDV-RNA below the limit of quantification (LOQ: <1,000 copies/ml) and one near LOQ (1450 copies/ml), all concomitantly treated with interferon. There were no significant changes in HBsAg levels for either group [TDF alone: -0.008 log10 IU/ml per month (95% CI: -0.019, 0.004), TDF+IFN:-0.011 log10 IU/ml per month (95% CI: -0.037, 0.015)] and no significant difference in slope between treatment groups (p=0.8). Interferon therapy might be more effective after extended previous anti-HBV antiviral exposure among triinfected patients; however, the long-term implications of these findings remain unknown.

Prevalence and clinical course of hepatitis delta infection in Greece: a 13-year prospective study

BACKGROUND & AIMS

Hepatitis D virus (HDV) has decreased in Europe, but recent reports indicate a rising trend. We report the epidemiological changes, clinical progress, and effect of treatment on the natural course of HDV infection in Greece during the last 13 years.

METHODS

Prospective data were extracted from the HepNet.Greece Cohort-Study.

RESULTS

Since 1997, 4673 chronic HBV (CHB) cases (4527 adults, 146 children) have been followed prospectively. Two thousand one hundred thirty-seven patients were tested for anti-HDV [101 (4.7%) positive]. Anti-HDV testing in Greece decreased significantly (57.0% before 2003, 35.3% thereafter; p<0.001). Anti-HDV prevalence among HBsAg-positives was 4.2%; lower in native Greeks (2.8%) than in immigrants (7.5%) or in children (15.3%; p<0.001). Within 2.3 years of follow-up, HDV occurred in 11/2047 HBsAg-positive patients (2.2 new delta-infected adults and 8.7 children per 1000 HBsAg-positive annually). HDV-positive compared to CHB adults were younger (p=0.035) and had more active and advanced disease at baseline, as indicated by laboratory indices and the higher prevalence of cirrhosis at younger age. During a 4.2-year median observation, significantly more anti-HDV-positive than CHB adults developed a liver-related first event (20.0% vs. 8.5%, p Log-rank=0.014).Treatment was received by 46/90 (51.1%) patients, 40 of them interferon-based. In multivariable analysis, interferon significantly decreased disease progression in HDV-positive patients [HR=0.14 (95% CI: 0.02-0.86; p=0.033)].

CONCLUSIONS

In Greece, HDV serology is currently tested in only one-third of HBsAg-positive patients. HDV prevalence is lower in native Greeks compared to immigrants, who may contribute >50% of the HDV infection burden in Greece. Data show that HDV infection is a rapidly progressive disease, but interferon-based treatment may alter its course.

Hepatitis in the elderly: still a scourge

Liver disease presents with classic symptoms: fatigue, anorexia that progresses to nausea and vomiting, muscle and joint pain, and jaundice. Its most common cause is viral infection (hepatitis) with one of the hepatotropic hepatitis viruses. Although all types of hepatitis cause liver disease, their modes of transmission differ, and treatment may or may not be an option. In all types of hepatitis, people older than 65 years of age tend to develop more severe disease than those who are younger. Hepatitis A is rare in the United States, usually resolves completely with rest and supportive care, and there is no drug treatment. The Food and Drug Administration has approved several medications for hepatitis B, although comorbidities in the elderly may preclude their use. Hepatitis C is generally treated with interferon alpha and ribavirin in patients who can tolerate these agents. Chronic hepatitis D infection is more aggressive than chronic hepatitis B infection, leading to cirrhosis within two years in 10% to 15% of patients. Treatment with interferon for at least one year is recommended, but may not help. Hepatitis E virus infection-typically associated with large waterborne epidemics and endemic in Asia, Africa, and Mexico-is poorly understood and reported only sporadically in the United States. Consultant pharmacists can provide invaluable input concerning management of patients with hepatitis since few guidelines are available. Treatment is complex and often associated with side effects, and it is costly to treat. Complete adherence is critical. Residents, their families, and long-term care staff will need education and support in treating these patients. Pharmacist involvement is especially important as newly approved agents become available; side effects can cause clinicians and patients to abandon treatment.