Interferon-α for patients with chronic hepatitis delta: a systematic review of randomized clinical trials

Hepatitis delta: In vitro evaluation of cytotoxicity and cytokines involved in PEG-IFN therapy

The treatment for hepatitis Delta virus (HDV) still consists of Pegylated interferon (PEG-IFN) combined with inhibitors of Hepatitis B virus (HBV) replication. In some patients may be occur a virological response, which means a negative HDV RNA 6 months after stopping treatment. In this study it was conducted an in vitro approach with the aim to mimic possible immunological events that are observed in patients responding to PEG-IFN therapy. Jurkat cells (human T lymphocyte cell line) were employed alone or co-cultured with THP-1 (human monocytic cell line) and stimulated with controls and HBV Surface Antigen (HBsAg), Small-Delta Antigen (SHDAg), and HBsAg + SHDAg combined. Twenty-four hours stimulation with SHDAg and/or HBSAg led to a toxic profile in a co-culture condition and cell supernatants were collected for cytokines quantification. PEG-IFN was added and cells were incubated for additional 24 h. Co-cultured cells incubated with the association (SHDAg + PEG-IFN) significantly produced levels of IFN-γ, IL-2 and IL-12. On the other hand, the HBsAg alone was able to inhibit the production of IFN-γ, suggesting that this antigen may hinder the treatment exclusively with PEG-IFN.

Endothelial cell functions impaired by interferon in vitro: Insights into the molecular mechanism of thrombotic microangiopathy associated with interferon therapy

INTRODUCTION

Interferon (IFN)-α and IFN-β approved for treatment of chronic hepatitis C viral infection and multiple sclerosis respectively have been linked to thrombotic microangiopathy (TMA) affecting renal function. Since the molecular mechanisms underlying this severe complication remain largely unclear, we aimed to investigate whether IFN affects directly in vitro endothelial cell functions associated with angiogenesis and blood haemostasis, as well as endothelial cell-derived vasodilators of nitric oxide (NO) and prostacyclin.

METHODS

Proliferation and survival of human umbilical vein endothelial cells (HUVECs) were measured by BrdU incorporation and alamarBlue assays. Angiogenesis was evaluated in co-cultures of HUVECs and human dermal fibroblasts. Fibrinolysis molecules were measured with ELISA. NO and prostacyclin were measured using a fluorescent NO-specific probe and a competitive enzyme immunoassay, respectively.

RESULTS

HUVEC proliferation was dose-dependently inhibited by IFN-β1a and IFN-β1b, but not by IFN-α2a and IFN-α2b. Consistently, IFN-β1a and IFN-β1b also reduced survival of HUVECs, but this again was not observed with IFN-α. However, both IFN subtypes inhibited VEGF-induced development of capillary-like structures, but the effect of IFN-α was less potent than IFN-β. In addition, both IFN subtypes upregulated interferon inducible protein 10 production from treated co-cultures while suppressing angiogenesis. Furthermore, intracellular NO generation was reduced by IFN-α2a and IFN-β1a, whereas prostacyclin release from HUVECs was not affected by IFN. Importantly, both IFN-β1a- and IFN-β1b-treated HUVECs showed a marked reduction in urokinase-type plasminogen activator release and a much greater secretion of plasminogen activator inhibitor-1 than tissue-type plasminogen activator compared with untreated cells, suggesting decreased fibrinolytic activity. IFN-α, however was less effective in modulating the fibrinolysis system.

CONCLUSIONS

We demonstrate the detrimental effects of IFN on endothelial cell functions mediated with angiogenesis and fibrinolysis, which could potentially cause the loss of physiological endothelium thromboresistance and facilitate the development of vascular complications in a clinical setting. Mechanistically, our findings have implications for understanding how IFN therapy can foster the development of TMA.

Functional Polymorphism in the Interleukin 6 (IL6) Gene with Respect to Depression Induced in the Course of Interferon-α and Ribavirin Treatment in Chronic Hepatitis Patients

Interleukin (IL)-6 is a multifactorial cytokine known to be increased in patients with chronic hepatitis C (CHC) and to be predictive of depression incidence. The aim of the study was to explore the association between IL6 gene C-174G polymorphism and depressive symptom severity in the longitudinal study design following the course of pegylated interferon/ribavirin treatment in CHC patients. In our study, we included 62 CHC subjects. They were assessed using present state examination, Beck Depression Inventory (BDI) and Montgomery Åsberg Depression Rating Scale (MADRS) at weeks 0, 3, 5, 9, 13, 24 and 24 weeks after the end of treatment. The risk of depression was associated with higher baseline MADRS score and BDI score. Interestingly, when stratified by IL6 C-174G polymorphism, higher baseline depressive symptom severity measured by MADRS and BDI predicted higher risk of depression in the course of antiviral treatment only in high IL-6 producers-G allele carriers (patients with GG and CG genotypes) (p = 0.004, p = 0.00008, respectively). There is interaction between severity of baseline depressive symptoms at the beginning of antiviral therapy and IL6 gene C-174G polymorphism leading to increased risk for the development of depressive episode in CHC patients in the course of antiviral treatment.

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.

Asian-Pacific clinical practice guidelines on the management of hepatitis B: a 2015 update

Worldwide, some 240 million people have chronic hepatitis B virus (HBV), with the highest rates of infection in Africa and Asia. Our understanding of the natural history of HBV infection and the potential for therapy of the resultant disease is continuously improving. New data have become available since the previous APASL guidelines for management of HBV infection were published in 2012. The objective of this manuscript is to update the recommendations for the optimal management of chronic HBV infection. The 2015 guidelines were developed by a panel of Asian experts chosen by the APASL. The clinical practice guidelines are based on evidence from existing publications or, if evidence was unavailable, on the experts' personal experience and opinion after deliberations. Manuscripts and abstracts of important meetings published through January 2015 have been evaluated. This guideline covers the full spectrum of care of patients infected with hepatitis B, including new terminology, natural history, screening, vaccination, counseling, diagnosis, assessment of the stage of liver disease, the indications, timing, choice and duration of single or combination of antiviral drugs, screening for HCC, management in special situations like childhood, pregnancy, coinfections, renal impairment and pre- and post-liver transplant, and policy guidelines. However, areas of uncertainty still exist, and clinicians, patients, and public health authorities must therefore continue to make choices on the basis of the evolving evidence. The final clinical practice guidelines and recommendations are presented here, along with the relevant background information.

Efficacy of prolonged tenofovir therapy on hepatitis delta in HIV-infected patients

BACKGROUND

Hepatitis delta virus (HDV) produces the most severe form of chronic viral hepatitis. We explored whether prolonged tenofovir exposure might be beneficial on hepatitis delta in HIV-infected patients.

METHODS

All HIV-infected patients with hepatitis delta followed at our institution since year 2000 were retrospectively examined. Serum HBV-DNA and HDV-RNA were quantified using commercial assays. Liver fibrosis was measured using elastometry.

RESULTS

A total of 19 HIV/delta patients were identified. All were viremic for HDV and 11 for HBV. After a median tenofovir exposure of 58 months, all had undetectable HBV-DNA and 10 (53%) had undetectable HDV-RNA. The median drop in HDV-RNA in the remaining nine HDV viremic patients at the end of follow-up was 2.4 log copies/ml. A reduction above 30% in liver stiffness occurred in six out 10 (60%) patients who achieved undetectable HDV-RNA, whereas hepatic stiffness did not change in the remaining HDV viremic patients (P = 0.03). Serum HBsAg concentrations did not decline significantly, although HBsAg seroclearance occurred in three patients, all of whom became negative for HDV-RNA.

CONCLUSION

Long-term exposure to tenofovir significantly reduced serum HDV-RNA apart from completely suppressing HBV-DNA in HIV-infected patients with hepatitis delta. This virological benefit is accompanied by significant improvements in liver fibrosis.

Hepatitis delta is a major determinant of liver decompensation events and death in HIV-infected patients

BACKGROUND

Coinfection with hepatitis viruses is common in individuals infected with human immunodeficiency virus (HIV) and has become a leading cause of complications and death in those receiving antiretroviral therapy (ART).

METHODS

We retrospectively examined the effect of coinfection with hepatitis B, C, and/or D viruses (HBV, HCV, HDV, respectively) on liver decompensation events (ascites, variceal bleeding, encephalopathy, and/or hepatocellular carcinoma) and liver-related mortality in HIV-positive patients on regular follow-up since the year 2004 at a reference HIV clinic in Madrid, Spain.

RESULTS

A total of 1147 HIV-infected patients (mean age, 42 years; 81% males; 46% intravenous drug users, 85.4% on ART) were analyzed. Mean follow-up was 81.2 ± 17.8 months. At baseline, 521 patients (45.4%) were HCV-antibody positive, 85 (7.4%) were hepatitis B surface antigen positive, and 17 (1.5%) were anti-HDV positive. A total of 233 HIV/HCV-coinfected patients received antiviral therapy for HCV, of whom 106 (45%) achieved sustained virologic response (SVR). Overall, 15 patients died of liver-related complications and 26 developed hepatic decompensation events. Taking as controls the 524 HIV-monoinfected patients, HDV coinfection (adjusted hazard ratio [AHR], 7.5; 95% confidence interval [CI], 1.84-30.8; P = .005) and baseline liver stiffness (AHR, 1.1; 95% CI, 1.07-1.13; P < .0001) were associated with a higher rate of liver-related morbidity and mortality. In contrast, SVR following hepatitis C therapy in HIV/HCV-coinfected patients was protective (AHR, 0.11; 95% CI, .01-.86; P = .03).

CONCLUSIONS

Hepatitis delta is associated with a high rate of death and liver decompensation events in HIV-infected patients on ART.

Interferon alpha-2b therapy in chronic hepatitis delta

BACKGROUND

Approximately 5% of hepatitis B virus (HBV) carriers are coinfected with hepatitis D virus (HDV). HBV/HDV coinfection is a major cause of cirrhosis and end stage liver disease in chronic HBsAg carriers. The only approved therapy for chronic hepatitis delta is interferon alpha (IFN α) in either pegylated or conventional forms. Although higher doses and longer durations of IFN α therapy in HBV/HDV coinfected patients are currently applied, yet treatment response is low.

OBJECTIVES

We aimed to determine the efficacy of IFN α-2b therapy in patients with HBV/HDV coinfection.

PATIENTS AND METHODS

In this cross sectional study, 20 HBsAg carriers with positive Anti-HDVAb and RT-PCR for HDV RNA were recruited and treated for three year duration with 5 million units (MU) of IFN α-2b, three times weekly or one year with 5 MU of IFN α-2b daily. Sustained virological response (SVR) was defined as a negative qualitative HDV RT-PCR, 6 months after treatment cessation.

RESULTS

Overall, 3 (15%) subjects achieved SVR, 10 cases (50%) relapsed after treatment cessation and 7 (35%) patients did not clear HDV during the treatment.

CONCLUSIONS

HDV coinfection with HBV had very low response rate to high doses and long durations of IFN α-2b therapy.

Hepatitis delta: epidemiology, diagnosis and management 36 years after discovery

With recent studies showing increased prevalence of hepatitis delta (HDV) even in the US, Australia, and some countries in Europe, and very high prevalence in endemic regions, HDV infection is far from being a disappearing disease. Although immigrants from endemic countries have been shown to have increased risk, studies have clearly shown that the disease is not solely appearing in traditional high-risk groups. Recent studies provide increasing evidence that sexual transmission may be an important factor in HDV infection spread. Based on the totality of evidence showing increased disease progression and substantially increased risk of cirrhosis in HDV-infected CHB patients, and the current studies showing higher than expected prevalence, it is time to call for HDV screening of all CHB patients. HDV viral load detection and measurement should be considered in all patients whether or not they are anti-HDV-positive. With universal screening of CHB patients for HDV, earlier diagnosis and consideration of treatment would be possible. Current treatment of HDV is IFN-based therapy with or without HBV antivirals, but current research indicates the possibility that prenylation inhibitors, entry inhibitors, HBsAg release inhibitors, or other therapies currently in the pipeline may provide more effective therapy in the future. In addition, universal screening would serve the important public health goal of allowing patients to be educated on their status and on the need for HDV-negative patients to protect themselves against superinfection and for HDV-infected patients to protect against transmission to others. Further studies and global awareness of HDV infection are needed.

Essential role for the Mnk pathway in the inhibitory effects of type I interferons on myeloproliferative neoplasm (MPN) precursors

The mechanisms of generation of the antineoplastic effects of interferons (IFNs) in malignant hematopoietic cells remain to be precisely defined. We examined the activation of type I IFN-dependent signaling pathways in malignant cells transformed by Jak2V617F, a critical pathogenic mutation in myeloproliferative neoplasms (MPNs). Our studies demonstrate that during engagement of the type I IFN receptor (IFNAR), there is activation of Jak-Stat pathways and also engagement of Mnk kinases. Activation of Mnk kinases is regulated by the Mek/Erk pathway and is required for the generation of IFN-induced growth inhibitory responses, but Mnk kinase activation does not modulate IFN-regulated Jak-Stat signals. We demonstrate that for type I IFNs to exert suppressive effects in malignant hematopoietic progenitors from patients with polycythemia vera, induction of Mnk kinase activity is required, as evidenced by studies involving pharmacological inhibition of Mnk or siRNA-mediated Mnk knockdown. Altogether, these findings provide evidence for key and essential roles of the Mnk kinase pathway in the generation of the antineoplastic effects of type I IFNs in Jak2V617F-dependent MPNs.

Cytokine synergy: an underappreciated contributor to innate anti-viral immunity

Inflammatory cytokines, such as tumor necrosis factor and the members of the interferon family, are potent mediators of the innate anti-viral immune response. The intracellular anti-viral states resulting from treatment of cultured cells with each of these molecules independently has been well studied; but, within complex tissues, the early inflammatory response is likely mediated by simultaneously expressed mixtures of these, and other, protective anti-viral cytokines. Such cytokine mixtures have been shown to induce potently synergistic anti-viral responses in vitro which are more complex than the simple summation of the individual cytokine response profiles. The physiological role of this 'cytokine synergy', however, remains largely unappreciated in vivo. This brief commentary will attempt to summarize the potential effects and mechanisms of anti-viral cytokine synergy as well as present several 'real-world' applications where this phenomenon might play an important role.

Treatment options for hepatitis delta virus infection

The hepatitis D virus (HDV), the smallest virus known to infect man, causes the most severe form of chronic viral hepatitis, hepatitis delta. It is estimated that about 15 to 20 million people are suffering from chronic HDV infection. HDV is a defective satellite virus depending on the hepatitis B surface antigen (HBsAg) for transmission. Chronic hepatitis delta is associated with a rapid progression of liver fibrosis and a high prevalence of liver cirrhosis, even in younger patients. Immunization against hepatitis B virus (HBV) protects from HDV infection, but there is no specific vaccine against HDV available for HBsAg-positive individuals. Treatment options for hepatitis delta patients are limited. So far, only interferon-alpha has shown an antiviral efficacy against HDV. Recent trials showed sustained virological response rates concerning HDV in 25 %-30 % of patients treated with pegylated interferons. HDV is dominant over HBV in the majority of cases, but HBV DNA-positive subjects should be treated with HBV polymerase inhibitors. Combination therapy of pegylated interferon-alpha and adefovir showed a more pronounced HBsAg decline, but the exact role of combination therapies in hepatitis delta requires further investigation. Alternative future treatment strategies may include prenylation inhibitors and HBV entry inhibitors, which are in early clinical development.

Interferome v2.0: an updated database of annotated interferon-regulated genes

Interferome v2.0 (http://interferome.its.monash.edu.au/interferome/) is an update of an earlier version of the Interferome DB published in the 2009 NAR database edition. Vastly improved computational infrastructure now enables more complex and faster queries, and supports more data sets from types I, II and III interferon (IFN)-treated cells, mice or humans. Quantitative, MIAME compliant data are collected, subjected to thorough, standardized, quantitative and statistical analyses and then significant changes in gene expression are uploaded. Comprehensive manual collection of metadata in v2.0 allows flexible, detailed search capacity including the parameters: range of -fold change, IFN type, concentration and time, and cell/tissue type. There is no limit to the number of genes that can be used to search the database in a single query. Secondary analysis such as gene ontology, regulatory factors, chromosomal location or tissue expression plots of IFN-regulated genes (IRGs) can be performed in Interferome v2.0, or data can be downloaded in convenient text formats compatible with common secondary analysis programs. Given the importance of IFN to innate immune responses in infectious, inflammatory diseases and cancer, this upgrade of the Interferome to version 2.0 will facilitate the identification of gene signatures of importance in the pathogenesis of these diseases.