Pegylated interferons alpha2a and alpha2b in the treatment of chronic hepatitis C

A Synopsis of Hepatitis C Virus Treatments and Future Perspectives

Hepatitis C virus (HCV) infection is a worldwide public health problem. Chronic infection with HCV can lead to liver cirrhosis or cancer. Although some immune-competent individuals can clear the virus, others develop chronic HCV disease due to viral mutations or an impaired immune response. IFNs type I and III and the signal transduction induced by them are essential for a proper antiviral effect. Research on the viral cycle and immune escape mechanisms has formed the basis of therapeutic strategies to achieve a sustained virological response (SVR). The first therapies were based on IFNα; then, IFNα plus ribavirin (IFN-RBV); and then, pegylated-IFNα-RBV (PEGIFNα-RIV) to improve cytokine pharmacokinetics. However, the maximum SVR was 60%, and several significant side effects were observed, decreasing patients' treatment adherence. The development of direct-acting antivirals (DAAs) significantly enhanced the SVR (>90%), and the compounds were able to inhibit HCV replication without significant side effects, even in paediatric populations. The management of coinfected HBV-HCV and HCV-HIV patients has also improved based on DAA and PEG-IFNα-RBV (HBV-HCV). CD4 cells are crucial for an effective antiviral response. The IFNλ3, IL28B, TNF-α, IL-10, TLR-3, and TLR-9 gene polymorphisms are involved in viral clearance, therapeutic responses, and hepatic pathologies. Future research should focus on searching for strategies to circumvent resistance-associated substitution (RAS) to DAAs, develop new therapeutic schemes for different medical conditions, including organ transplant, and develop vaccines for long-lasting cellular and humoral responses with cross-protection against different HCV genotypes. The goal is to minimise the probability of HCV infection, HCV chronicity and hepatic carcinoma.

Electrically regulated cell-based intervention for viral infections

This work reports on an engineered cell that-when electrically stimulated-synthesizes a desired protein, that is, ES-Biofactory. The platform has been used to express interferon (IFN)-β as a universal antiviral protein. Compelling evidence indicates the inevitability of new pandemics and drives the need for a pan-viral intervention that may be quickly deployed while more specific vaccines are in development. Toward this goal, a fast-growing mammalian cell (Chassis) has been engineered with multiple synthetic elements. These include-(1) a voltage-gated Ca²⁺ channel (Voltage-Sensor) that, upon sensing the electric field, activates the (2) Ca²⁺-mediated signaling pathway (Actuator) to upregulate (3) IFN-β, via an engineered antiviral transgene (Effector), that is, ES-Biofactory➔IFN-β. The antiviral effects of the ES-Biofactory➔IFN-β have been validated on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected cells. The irradiated ES-Biofactory, that does not exhibit oncogenic capacity, continues to exert antiviral effect. The resulting ES-Biofactory➔IFN-β uses a novel signaling pathway that, unlike the natural IFN synthesis pathway, is not subject to viral interference. Once clinically validated, the ES-Biofactory will be a universal antiviral cell therapy that can be immediately deployed in the event of an outbreak. The platform may also be useful in treating other diseases including cancer and autoimmune disorders.

Direct and indirect effects of IFN-α2b in malignancy treatment: not only an archer but also an arrow

Interferon-α2b (IFN-α2b) is a highly active cytokine that belongs to the interferon-α (IFN-α) family. IFN-α2b has beneficial antiviral, antitumour, antiparasitic and immunomodulatory activities. Direct and indirect antiproliferative effects of IFN-α2b have been found to occur via multiple pathways, mainly the JAK-STAT pathway, in certain cancers. This article reviews mechanistic studies and clinical trials on IFN-α2b. Potential regulators of the function of IFN-α2b were also reviewed, which could be utilized to relieve the poor response to IFN-α2b. IFN-α2b can function not only by enhancing the systematic immune response but also by directly killing tumour cells. Different parts of JAK-STAT pathway activated by IFN-α2b, such as interferon alpha and beta receptors (IFNARs), Janus kinases (JAKs) and IFN‐stimulated gene factor 3 (ISGF3), might serve as potential target for enhancing the pharmacological action of IFN-α2b. Despite some issues that remain to be solved, based on current evidence, IFN-α2b can inhibit disease progression and improve the survival of patients with certain types of malignant tumours. More efforts should be made to address potential adverse effects and complications.

Insights on Development Aspects of Polymeric Nanocarriers: The Translation from Bench to Clinic

Scientists are focusing immense attention on polymeric nanocarriers as a prominent delivery vehicle for several biomedical applications including diagnosis of diseases, delivery of therapeutic agents, peptides, proteins, genes, siRNA, and vaccines due to their exciting physicochemical characteristics which circumvent degradation of unstable drugs, reduce toxic side effects through controlled release, and improve bioavailability. Polymers-based nanocarriers offer numerous benefits for in vivo drug delivery such as biocompatibility, biodegradability, non-immunogenicity, active drug targeting via surface modification, and controlled release due to their pH—and thermosensitive characteristics. Despite their potential for medicinal use, regulatory approval has been achieved for just a few. In this review, we discuss the historical development of polymers starting from their initial design to their evolution as nanocarriers for therapeutic delivery of drugs, peptides, and genes. The review article also expresses the applications of polymeric nanocarriers in the pharmaceutical and medical industry with a special emphasis on oral, ocular, parenteral, and topical application of drugs, peptides, and genes over the last two decades. The review further examines the practical, regulatory, and clinical considerations of the polymeric nanocarriers, their safety issues, and directinos for future research.

Characterization of SARS-CoV-2 Evasion: Interferon Pathway and Therapeutic Options

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for the current COVID-19 pandemic. SARS-CoV-2 is characterized by an important capacity to circumvent the innate immune response. The early interferon (IFN) response is necessary to establish a robust antiviral state. However, this response is weak and delayed in COVID-19 patients, along with massive pro-inflammatory cytokine production. This dysregulated innate immune response contributes to pathogenicity and in some individuals leads to a critical state. Characterizing the interplay between viral factors and host innate immunity is crucial to better understand how to manage the disease. Moreover, the constant emergence of new SARS-CoV-2 variants challenges the efficacy of existing vaccines. Thus, to control this virus and readjust the antiviral therapy currently used to treat COVID-19, studies should constantly be re-evaluated to further decipher the mechanisms leading to SARS-CoV-2 pathogenesis. Regarding the role of the IFN response in SARS-CoV-2 infection, in this review we summarize the mechanisms by which SARS-CoV-2 evades innate immune recognition. More specifically, we explain how this virus inhibits IFN signaling pathways (IFN-I/IFN-III) and controls interferon-stimulated gene (ISG) expression. We also discuss the development and use of IFNs and potential drugs controlling the innate immune response to SARS-CoV-2, helping to clear the infection.

Tale of Viruses in Male Infertility

Male infertility is a condition where the males either become sterile or critically infertile. The World Health Organisation assessed that approximately 9% of the couple have fertility issues where the contribution of the male partner was estimated to be 50%. There are several factors that can amalgamate to give rise to male infertility. Among them are lifestyle factors, genetic factors and as well as several environmental factors. The causes of male infertility may be acquired, congenital or sometimes idiopathic. All these factors adversely affect the spermatogenesis process as well as they impart serious threats to male genital organs thus resulting in infertility. Viruses are submicroscopic pathogenic agents that rely on host for their replication and survival. They enter the host cell, hijack the host cell machinery to aid their own replication and exit the cell for a new round of infection. With the growing abundance of different types of viruses and the havoc they have stirred in the form of pandemics, it is very essential to decipher their route of entry inside the human body and understand their diverse functional roles in order to combat them. In this chapter, we will review how viruses invade the male genital system thus in turn leading to detrimental consequence on male fertility. We will discuss the tropism of various viruses in the male genital organs and explore their sexual transmissibility. This chapter will summarise the functional and mechanistic approaches employed by the viruses in inducing oxidative stress inside spermatozoa thus leading to male infertility. Moreover, we will also highlight the various antiviral therapies that have been studied so far in order to ameliorate viral infection in order to combat the harmful consequences leading to male infertility.

Efficacy and safety of interferon α-2b spray for herpangina in children: A randomized, controlled trial

OBJECTIVES

The treatment of acute herpangina is inconsistent. We aim to evaluate the effectiveness and safety of interferon α-2b spray versus Ribavirin for this disease.

METHODS

A randomized, controlled trial was conducted in eight hospitals in China between 2016 and 2018. 668 patients (1-7 years old) were randomized into an experimental group (treated with Interferon α-2b spray) or control group (received Ribavirin Aerosol). Body temperature returning to normal within 72 h and remaining so for 24 h was the primary outcome; release of oral herpes and adverse events were the secondary outcomes.

RESULTS

(1) The average age of onset was 2.5 years old. (2) After 72 h treatment, body temperature of 98.5% patients in experimental group and 94.3% in control group returned to normal and remained so for 24 h (P = 0.004). The differences were greater at 48 h treatment (95.2% vs. 85.9%, P < 0.001) and at 24 h (77.5% vs. 66.5%, P = 0.001). (3) The rate of improved oral herpes in the experimental group was higher than that in control group (46.7% vs.37.1%, P = 0.011). No adverse reaction occurred.

CONCLUSIONS

Local application of recombinant interferon α-2b spray showed better efficacy for acute herpangina in children. It was safe for use.

[Immunotoxins and immunocytokines]

Cytokines and biological toxins represent two potent classes of biomolecules that have long been explored for their potential as therapeutics. Considerable side effects and poor pharmacokinetics frequently observed with both have limited their broad application. Recombinant protein engineering has allowed the construction of immunocytokines and immunotoxins that seek to exploit the advantageous properties of immunoglobulins to address these issues. Whole antibodies, antibody fragments, constant domains and derivatives have been fused genetically to a range of cytokines and toxins. This review considers the strategies that have been employed and the problems sought to be resolved in the clinical evaluation of this class of biotherapeutic.

Site-Specific DBCO Modification of DEC205 Antibody for Polymer Conjugation

The design of multifunctional polymer-based vectors, forming pDNA vaccines, offers great potential in cancer immune therapy. The transfection of dendritic immune cells (DCs) with tumour antigen-encoding pDNA leads to an activation of the immune system to combat tumour cells. In this work, we investigated the chemical attachment of DEC205 antibodies (aDEC205) as DC-targeting structures to polyplexes of P(Lys)-b-P(HPMA). The conjugation of a synthetic block copolymer and a biomacromolecule with various functionalities (aDEC205) requires bioorthogonal techniques to avoid side reactions. Click chemistry and in particular the strain-promoted alkyne-azide cycloaddition (SPAAC) can provide the required bioorthogonality. With regard to a SPAAC of both components, we firstly synthesized two different azide-containing block copolymers, P(Lys)-b-P(HPMA)-N₃(stat) and P(Lys)-b-P(HPMA)-N₃(end), for pDNA complexation. In addition, the site-specific incorporation of ring-strained dibenzocyclooctyne (DBCO) moieties to the DEC205 antibody was achieved by an enzymatic strategy using bacterial transglutaminase (BTG). The chemical accessibility of DBCO molecules within aDEC205 as well as the accessibility of azide-functionalities on the polyplex' surface were investigated by various SPAAC experiments and characterized by fluorescence correlation spectroscopy (FCS).

Advances in the treatment of relapsing-remitting multiple sclerosis: the role of pegylated interferon β-1a

Multiple sclerosis (MS) is a progressive, neurodegenerative disease with unpredictable phases of relapse and remission. The cause of MS is unknown, but the pathology is characterized by infiltration of auto-reactive immune cells into the central nervous system (CNS) resulting in widespread neuroinflammation and neurodegeneration. Immunomodulatory-based therapies emerged in the 1990s and have been a cornerstone of disease management ever since. Interferon β (IFNβ) was the first biologic approved after demonstrating decreased relapse rates, disease activity and progression of disability in clinical trials. However, frequent dosing schedules have limited patient acceptance for long-term therapy. Pegylation, the process by which molecules of polyethylene glycol are covalently linked to a compound, has been utilized to increase the half-life of IFNβ and decrease the frequency of administration required. To date, there has been one clinical trial evaluating the efficacy of pegylated IFN. The purpose of this article is to provide an overview of the role of IFN in the treatment of MS and evaluate the available evidence for pegylated IFN therapy in MS.

Current therapy for chronic hepatitis C: The role of direct-acting antivirals

One of the most exciting developments in antiviral research has been the discovery of the direct-acting antivirals (DAAs) that effectively cure chronic hepatitis C virus (HCV) infections. Based on more than 100 clinical trials and real-world studies, we provide a comprehensive overview of FDA-approved therapies and newly discovered anti-HCV agents with a special focus on drug efficacy, mechanisms of action, and safety. We show that HCV drug development has advanced in multiple aspects: (i) interferon-based regimens were replaced by interferon-free regimens; (ii) genotype-specific drugs evolved to drugs for all HCV genotypes; (iii) therapies based upon multiple pills per day were simplified to a single pill per day; (iv) drug potency increased from moderate (∼60%) to high (>90%) levels of sustained virologic responses; (v) treatment durations were shortened from 48 to 12 or 8 weeks; and (vi) therapies could be administered orally regardless of prior treatment history and cirrhotic status. However, despite these remarkable achievements made in HCV drug discovery, challenges remain in the management of difficult-to-treat patients.

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HCV genotype-specific drugs evolve to pan-genotypic drugs.

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Drug potency increases from moderate (∼60%) to high (>90%) levels of sustained virologic response.

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Treatment durations are shortened from a 48-week to 12-week or 8-week period.

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HCV therapies based upon multiple pills per day are simplified to a single pill per day.

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HCV therapies are administered orally regardless of prior treatment history and cirrhotic status.

Efficacy and safety of interferon-α2b spray in the treatment of hand, foot, and mouth disease: a multicenter, randomized, double-blind trial

Hand, foot, and mouth disease (HFMD) is a common infectious enterovirus disease, occurring mostly in infants and children younger than 7 years with potentially fatal complications. Therefore, we evaluated the clinical efficacy and safety of recombinant human interferon (IFN)-α2b spray for treating mild HFMD in 400 patients in a randomized, open, controlled clinical trial. The patients were randomized to the IFN-α2b spray and placebo groups, and their temperature, skin rash, oral lesions, and appetite were monitored, while pathogen levels and safety were evaluated with a 7-day follow-up. The mean age of the patients was 20.1 ± 10.2 months. The median duration of fever, oral ulcers or vesicles (or both), and skin rash in addition to median time to regain appetite in the IFN-α2b spray group were shorter than they were in the placebo group. The number of virus-positive cases differed statistically between the two groups for the three follow-up detections. Additionally, the incidences of adverse events (AEs) and severe AEs (SAEs) were not significantly different between the two groups, and the SAEs were evidently unrelated to the IFN-α2b spray or placebo. Therefore, the IFN-α2b spray is suitable for topical treatment of HFMD, and it rapidly relieved fever, promoted oral lesions and subsidence of rash, enhanced appetite, promoted disease recovery, and was safe for application.

2015 Philip S. Portoghese Medicinal Chemistry Lectureship. Curing Hepatitis C Virus Infection with Direct-Acting Antiviral Agents: The Arc of a Medicinal Chemistry Triumph

The development of direct-acting antiviral agents that can cure a chronic hepatitis C virus (HCV) infection after 8-12 weeks of daily, well-tolerated therapy has revolutionized the treatment of this insidious disease. In this article, three of Bristol-Myers Squibb's HCV programs are summarized, each of which produced a clinical candidate: the NS3 protease inhibitor asunaprevir (64), marketed as Sunvepra, the NS5A replication complex inhibitor daclatasvir (117), marketed as Daklinza, and the allosteric NS5B polymerase inhibitor beclabuvir (142), which is in late stage clinical studies. A clinical study with 64 and 117 established for the first time that a chronic HCV infection could be cured by treatment with direct-acting antiviral agents alone in the absence of interferon. The development of small molecule HCV therapeutics, designed by medicinal chemists, has been hailed as "the arc of a medical triumph" but may equally well be described as "the arc of a medicinal chemistry triumph".

A Retrospective Study to Examine Healthcare Costs Related to Cardiovascular Events in Individuals with Hyperlipidemia

Introduction

Few studies have demonstrated the cost burden of cardiovascular events (CVEs) among patients with hyperlipidemia. The primary objective of this study was to determine the mean costs associated with CVEs among patients with hyperlipidemia by follow-up time period. Secondary objectives of this study included characterizing costs by CVE type and coronary heart disease (CHD) risk.

Methods

This retrospective cohort study used longitudinal claims to calculate payer costs according to CHD risk level and type of CVE, during several follow-up periods (acute and short-term, comprising year 1; plus years 2 and 3).

Results

There were 193,385 patients with hyperlipidemia with a CVE. Costs in the acute (30-day) period were highest ($22,404) driven by inpatient care (77%). Costs remained high ($15,133 in year 3) with ambulatory care (from 14% in acute to 37% in year 3) and pharmaceutical costs (from 2% in acute to 24% in year 3) representing a greater proportion. After second and third CVEs, acute costs were lower than for the first CVE. But in the post-acute periods, costs were higher after second and third CVEs than after first CVEs. Acute costs varied considerably by type of CVE ($9149 for transient ischemic attack to $54,251 for coronary artery bypass graft; P < 0.001), but post-acute costs were more similar across types. Costs differed by baseline CHD risk for all follow-up periods (P < 0.001), but less than by CVE type. As expected, patients without CVEs had significantly lower costs.

Conclusion

Among patients with hyperlipidemia, the economic burden of CVEs is substantial up to 3 years after a CVE. Costs remain high after subsequent CVEs and actually increase for non-inpatient utilization.

Funding

Amgen Inc.

Electronic supplementary material

The online version of this article (doi:10.1007/s12325-015-0264-7) contains supplementary material, which is available to authorized users.

Delivery of GM-CSF to Protect against Influenza Pneumonia

Background

Since adaptive immunity is thought to be central to immunity against influenza A virus (IAV) pneumonias, preventive strategies have focused primarily on vaccines. However, vaccine efficacy has been variable, in part because of antigenic shift and drift in circulating influenza viruses. Recent studies have highlighted the importance of innate immunity in protecting against influenza.

Methods

Granulocyte-macrophage colony stimulating factor (GM-CSF) contributes to maturation of mononuclear phagocytes, enhancing their capacity for phagocytosis and cytokine production.

Results

Overexpression of granulocyte macrophage-colony stimulating factor (GM-CSF) in the lung of transgenic mice provides remarkable protection against IAV, which depends on alveolar macrophages (AM). In this study, we report that pulmonary delivery of GM-CSF to wild type young and aged mice abrogated mortality from IAV.

Conclusion

We also demonstrate that protection is species specific and human GM-CSF do not protect the mice nor stimulates mouse immunity. We also show that IAV-induced lung injury is the culprit for side-effects of GM-CSF in treating mice after IAV infection, and introduce a novel strategy to deliver the GM-CSF to and retain it in the alveolar space even after IAV infection.

No correspondence between resistance mutations in the HCV-NS3 protease at baseline and early telaprevir-based triple therapy

Direct-acting antiviral (DAA)-based therapy is the new standard treatment for chronic hepatitis C virus (HCV) infection. However, protease inhibitor (PI)-resistant viral variants have been often described. This study aimed to examine HCV-NS3 protease variants at baseline and at 4 weeks under triple therapy. To this end, we analyzed the presence of variants in HCV-NS3 protease region from peripheral blood samples of 16 patients infected with HCV-1 at baseline and at 4 weeks of combined therapy with telaprevir, pegylated interferon, and ribavirin, using next-generation sequencing. Several variants with synonymous and non-synonymous amino acid substitutions were detected at both time points. Variants detected at low frequency corresponded to 74% (HCV-1a) and 35% (HCV-1b) of non-synonymous substitutions. We found nine PI-resistance-associated variants (V36A, T54S, V55I, Q80K, Q80R, V107I, I132V, D168E, M175L) in HCV-NS3 of 10 patients. There was no correspondence of resistance-associated variant profile between baseline and at 4 weeks. Moreover, these resistance variants at baseline and short-term treatment are not good predictors of outcome under triple therapy. Our study also shows a large number of others minor and major non-synonymous variants in HCV-NS3 early in telaprevir-based therapy that can be important for further drug resistance association studies with newly developed PI agents.

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HCV-NS3 protease variants were analyzed at baseline and 4 weeks of triple therapy.

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Synonymous and non-synonymous variants, even at low frequency, were detected.

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Nine PI resistance mutations were identified in 10/16 patients in both time points.

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There was no correspondence between resistance mutation at baseline and 4 weeks.

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We provide a comprehensive databank of non-synonymous variants in HCV-NS3.

Interferons: Success in anti-viral immunotherapy

The interferons (IFNs) are glycoproteins with strong antiviral activities that represent one of the first lines of host defense against invading pathogens. These proteins are classified into three groups, Type I, II and III IFNs, based on the structure of their receptors on the cell surface. Due to their ability to modulate immune responses, they have become attractive therapeutic options to control chronic virus infections. In combination with other drugs, Type I IFNs are considered as "standard of care" in suppressing Hepatitis C (HCV) and Hepatitis B (HBV) infections, while Type III IFN has generated encouraging results as a treatment for HCV infection in phase III clinical trials. However, though effective, using IFNs as a treatment is not without the need for caution. IFNs are such powerful cytokines that affect a wide array of cell types; as a result, patients usually experience unpleasant symptoms, with a percentage of patients suffering system wide effects. Thus, constant monitoring is required for patients treated with IFN in order to reach the treatment goals of suppressing virus infection and maintaining quality of life.

Oral delivery of oligomeric procyanidins in Apple Poly® enhances type I IFN responses in vivo

Type I IFN signaling is a central pathway that provides critical innate protection from viral and bacterial infection and can have regulatory outcomes in inflammatory settings. We determined previously that OPCs contained in the dietary supplement APP enhanced responses to type I IFN in vitro. Here, we confirm that OPCs from two different sources significantly increased pSTAT1, whereas a monomeric form of procyanidin did not. We hypothesized that similar responses could be induced in vivo following ingestion of APP. Ingestion of APP before injection of polyI:C enhanced in vivo responses to type I IFNs in mice. When human subjects ingested APP, enhanced responses to type I IFN and enhanced pSTAT1 ex vivo were detected, whereas ingestion of RES, a monomeric polyphenol, induced minimal such changes. Polyphenols are best known for induction of anti-inflammatory and antioxidant responses; however, our findings suggest a unique, nonantioxidant aspect of OPCs that is broadly applicable to many disease settings. The capacity of oral OPCs to enhance type I IFN signaling in vivo can augment innate protection and may, in part, contribute to the noted anti-inflammatory outcome of ingestion of OPCs from many sources.

Results of treatment of chronic hepatitis B with pegylated interferon

Persistent viral eradication or suppression through a defined course of Pegylated-interferon (PegIFN) or the administration of a long-term potent nucleot(s)ide analogues (NUCs) can impact positively the natural course of HBV infection by preventing disease progression. Despite the higher rates of off-therapy response achieved with PegIFN compared with NUC, its benefits are restricted to a subgroup of patients only. To increase the rates of patients who may benefit from PegIFN treatment, minimizing the adverse events, careful patient selections based on baseline features and on treatment HBsAg kinetics for individual treatment optimization are required.

Negative regulation of type I IFN expression by OASL1 permits chronic viral infection and CD8⁺ T-cell exhaustion

The type I interferons (IFN-Is) are critical not only in early viral control but also in prolonged T-cell immune responses. However, chronic viral infections such as those of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) in humans and lymphocytic choriomeningitis virus (LCMV) in mice overcome this early IFN-I barrier and induce viral persistence and exhaustion of T-cell function. Although various T-cell-intrinsic and -extrinsic factors are known to contribute to induction of chronic conditions, the roles of IFN-I negative regulators in chronic viral infections have been largely unexplored. Herein, we explored whether 2'-5' oligoadenylate synthetase-like 1 (OASL1), a recently defined IFN-I negative regulator, plays a key role in the virus-specific T-cell response and viral defense against chronic LCMV. To this end, we infected Oasl1 knockout and wild-type mice with LCMV CL-13 (a chronic virus) and monitored T-cell responses, serum cytokine levels, and viral titers. LCMV CL-13-infected Oasl1 KO mice displayed a sustained level of serum IFN-I, which was primarily produced by splenic plasmacytoid dendritic cells, during the very early phase of infection (2-3 days post-infection). Oasl1 deficiency also led to the accelerated elimination of viremia and induction of a functional antiviral CD8 T-cell response, which critically depended on IFN-I receptor signaling. Together, these results demonstrate that OASL1-mediated negative regulation of IFN-I production at an early phase of infection permits viral persistence and suppresses T-cell function, suggesting that IFN-I negative regulators, including OASL1, could be exciting new targets for preventing chronic viral infection.

Psychological, lifestyle and social predictors of hepatitis C treatment response: a systematic review

BACKGROUND

To increase cure rates for Hepatitis C, barriers to treatment adherence and completion must be identified and overcome.

AIMS

This study systematically reviewed evidence on the psychological, lifestyle and social determinants of achieving viral eradication with antiviral therapy.

METHODS

An electronic search strategy was used to identify relevant studies that examined psychological, lifestyle and social factors related to achieving a sustained virological response (SVR).

RESULTS

Thirty-four studies that matched our criteria were identified. Of the factors that predict response to treatment, Asian ethnicity was an independent predictor of SVR. We found an indirect relationship between diet and SVR, with non-responders to treatment consuming more polyunsaturated fatty acids, fats and carbohydrates than those who attained SVR. The effect of alcohol consumption relied on the amount consumed; fewer than 30 grams daily had no effect on SVR, whereas >70 grams daily had an adverse impact on a patient's ability to achieve SVR, with termination rates up to 44% in those who drank >2 drinks a day. Patients with psychiatric illnesses had comparable SVR rates to controls if they continued psychological therapy (average 42%), although discontinuation rates were high with 11 studies reporting rates from 14 to 48%.

CONCLUSIONS

There are major gaps in current knowledge of the impact of variables such as diet, exercise, attitudes and coping skills on cure rates in chronic Hepatitis C. Those who drink limited amounts of alcohol or have psychiatric disorders should be offered treatment for their disease, with adjunctive education and support to improve treatment completion.

Oral drug delivery systems using chemical conjugates or physical complexes

Oral delivery of therapeutics is extremely challenging. The digestive system is designed in a way that naturally allows the degradation of proteins or peptides into small molecules prior to absorption. For systemic absorption, the intact drug molecules must traverse the impending harsh gastrointestinal environment. Technologies, such as enteric coating, with oral dosage formulation strategies have successfully provided the protection of non-peptide based therapeutics against the harsh, acidic condition of the stomach. However, these technologies showed limited success on the protection of therapeutic proteins and peptides. Importantly, inherent permeability coefficient of the therapeutics is still a major problem that has remained unresolved for decades. Addressing this issue in the context, we summarize the strategies that are developed in enhancing the intestinal permeability of a drug molecule either by modifying the intestinal epithelium or by modifying the drug itself. These modifications have been pursued by using a group of molecules that can be conjugated to the drug molecule to alter the cell permeability of the drug or mixed with the drug molecule to alter the epithelial barrier function, in order to achieve the effective drug permeation. This article will address the current trends and future perspectives of the oral delivery strategies.

Interferon-lambda (IFN-λ) induces signal transduction and gene expression in human hepatocytes, but not in lymphocytes or monocytes

This study compared the ability of IFN-α and IFN-λ to induce signal transduction and gene expression in primary human hepatocytes, PBLs, and monocytes. IFN-α drug products are widely used to treat chronic HCV infection; however, IFN-α therapy often induces hematologic toxicities as a result of the broad expression of IFNARs on many cell types, including most leukocytes. rIFN-λ1 is currently being tested as a potential alternative to IFN-α for treating chronic HCV. Although IFN-λ has been shown to be active on hepatoma cell lines, such as HepG2 and Huh-7, its ability to induce responses in primary human hepatocytes or leukocytes has not been examined. We found that IFN-λ induces activation of Jak/STAT signaling in mouse and human hepatocytes, and the ability of IFN-λ to induce STAT activation correlates with induction of numerous ISGs. Although the magnitude of ISG expression induced by IFN-λ in hepatocytes was generally lower than that induced by IFN-α, the repertoire of regulated genes was quite similar. Our findings demonstrate that although IFN-α and IFN-λ signal through distinct receptors, they induce expression of a common set of ISGs in hepatocytes. However, unlike IFN-α, IFN-λ did not induce STAT activation or ISG expression by purified lymphocytes or monocytes. This important functional difference may provide a clinical advantage for IFN-λ as a treatment for chronic HCV infection, as it is less likely to induce the leukopenias that are often associated with IFN-α therapy.

Antiviral activity of the interferon α family: biological and pharmacological aspects of the treatment of chronic hepatitis C

INTRODUCTION

Type I interferons (IFNs) comprise a group of at least 13 structurally related subtypes of IFN-α with similar, but not identical, biological activities. Each subtype displays a unique activity profile; only IFN-α2a and IFN-α2b subtypes together with natural IFN-α preparations are currently used in the clinical practice, so that the remaining IFN-α subtypes are a still unexploited reservoir of opportunity also in the new era of direct-acting antiviral agents for the treatment of hepatitis C virus (HCV).

AREAS COVERED

This paper reviews recent progress in the study of the biology of IFN family, the antiviral action mechanism and the strategies employed by HCV to evade IFN action. Currently available IFN preparations for the treatment of chronic hepatitis C infection are described and what is currently known on the pharmacokinetics, pharmacodynamics and immunogenicity of IFN-α preparations used in clinical practice are summarized.

EXPERT OPINION

The characterization of multifunctional nature of IFN system together with recent advances in the identification of HCV IFN evasion strategies and the variety of host factors influencing IFN treatment response should be considered to improve HCV and other infectious diseases treatment in the future.

Effect of different interferonα2 preparations on IP10 and ET-1 release from human lung cells

Background

Alfa-interferons (IFNα2a, IFNα2b, 40KDa-PEGIFNα2a and 12KDa-PEGIFNα2b) are effective treatments for chronic hepatitis C infection. However, their usage has been associated with a variety of adverse events, including interstitial pneumonitis and pulmonary arterial hypertension. Although rare, these adverse events can be severe and potentially life-threatening, emphasizing the need for simple biomarkers of IFN-induced lung toxicity.

Methods

Human lung microvascular endothelial cells (HLMVEC), human pulmonary artery smooth muscle (HPASM) cells and A549 cells were grown under standard conditions and plated into 96- or 6-well plates. Cells were stimulated with various concentrations of different IFNs in hydrocortisone-free medium. After 24 and 48 hours, IP10 and ET-1 were measured by ELISA in conditioned medium. In a second set of experiments, cells were pre-treated with tumour necrosis factor-α (TNF-α) (10 ng/mL).

Results

IFNα2a, IFNα2b, 40KDa-PEGIFNα2a and 12KDa-PEGIFNα2b, but not IFNλ, induced IP10 (CXCL10) release and increased IP10 gene induction in HLMVEC. In addition, all four IFNα preparations induced IP10 release from HPASM cells and A549 cells pre-treated with TNFα. In each of these cell types, 40KDa-PEGIFNα2a was significantly less active than the native forms of IFNα2a, IFNα2b or 12KDa-PEGIFNα2b. Similarly, IFNα2a, IFNα2b and 12KDa-PEGIFNα2b, but not 40KDa-PEGIFNα2a, induced endothelin (ET)-1 release from HPASM cells.

Conclusions

Consistent with other interstitial pulmonary diseases, both IP10 and ET1 may serve as markers to monitor IFN-induced lung toxicity in patients. In addition, both markers may also serve to help characterize the risk associated with IFNα preparations to induce lung toxicity.

Chronic hepatitis C in saudi arabia: three years local experience in a university hospital

BACKGROUND

Chronic hepatitis C (CHC) is a global infection. In Saudi Arabia, the prevalence of CHC is declining due to the implementation of a blood screening program. However, CHC still remains a leading cause of liver cirrhosis and hepatocellular carcinoma.

OBJECTIVES

This is a retrospective study of CHC patients at the King Abdul Aziz University Hospital, Jeddah, Saudi Arabia.

PATIENTS AND METHODS

Out of a total of 291 CHC patients from the hepatology clinic at King Abdul Aziz University hospital, Jeddah, 279 patients were included in the present study. They were primarily male (152, 54.5%), with a mean age of 50.41 ± 1.72 years. The majority of patients were either Saudi (108, 38.7%) or Egyptian (60, 21.5%). A total of 61 patients received combination treatment with pegylated interferon and ribavirin, and one patient with sickle-cell anemia received pegylated INF monotherapy. Demographic, clinical and laboratory features of the CHC patients, and their responses to treatment were studied.

RESULTS

Decompensated cirrhosis was documented in 60 patients (21.5%), and hepatocellular carcinoma in 14 (5%). The mean level of serum alanine aminotransferase was 83.6 ± 231 u/L. The predominant genotype among the 70 patients tested, was genotype 4, followed by genotype 1 (39 and 18 patients, respectively). The sustained viral response (SVR) rate was 82.99%. The main predictive factors for SVR were baseline HCV viral load and rapid virologic response (RVR). The mean duration of follow-up was 4.2 ± .85 years. There were 24 patients who had liver disease-related mortality.

CONCLUSIONS

our data showed that 22% of CHC patients progress to cirrhosis and another 22% had treatment. Liver related mortality was more common in patients with advanced cirrhosis.

Type I and III interferons enhance IL-10R expression on human monocytes and macrophages, resulting in IL-10-mediated suppression of TLR-induced IL-12

Currently, only about 30-50% of chronic hepatitis C virus (HCV) and hepatitis B virus (HBV) patients respond to IFN-based therapy. It has been suggested that IL-10 is involved in suppressing the activity of type I IFNs on antigen-presenting cells (APCs). However, the interaction between type I IFNs and IL-10 is still not clear. Here we report that IFN-α priming upregulated the expression of IL-10R1 on monocytes, and subsequently IL-10 induced a higher level of STAT3 phosphorylation in IFN-primed cells. This indicates that IFN-α increased the sensitivity of monocytes to IL-10, and as a result, TLR-induced IL-12p70 by IFN-pretreated cells was suppressed. Interestingly, both IFN-β and IL-29, a member of the type III IFN family, comparably sensitized monocytes and macrophages to IL-10 stimulation, indicating a general effect of IFN on the activity of IL-10 in APCs. In summary, we demonstrate that one of the consequences of priming human APCs with IFN is to promote the cells' sensitivity to IL-10, which leads to the inhibition of TLR-induced IL-12p70 production. Therefore, type I and III IFNs induce a suboptimal activation of immune cells. These findings are relevant for the development of strategies to further improve IFN-based therapy for patients with multiple sclerosis or viral hepatitis.

Kinetic and dynamic computational model-based characterization of new proteins in mice: application to interferon alpha linked to apolipoprotein A-I

Interferon alpha linked to apolipoprotein A-I has been recently proposed as an improved interferon-based therapy. In the present study, we aimed to develop a computational model to gain further insight into the in vivo behaviour of this new fusion protein. In order to facilitate in vivo evaluation of interferon and the fusion protein without altering their biological properties, green fluorescent protein was incorporated into their structures. Kinetic and dynamic behaviour of both compounds was successfully described after plasmid hydrodynamic administration and in situ synthesis of the studied proteins. Results from the modelling exercise showed that apolipoprotein A-I conferred a modified kinetic behaviour, varying molecule distribution and prolonging half-life without altering liver dynamic performance. However, differences in the gene expression activity were observed at brain level between both compounds. Those differences could be explained by modifications in the dynamic, but also in the biodistribution properties, which would be worth evaluating in future experiments. Therefore, the modelling approach provided a global comprehension of a complex system and allowed us to compare the in vivo behaviour of both compounds and to identify critical aspects that might be important to understand the system better and suggests a need for new model-based experiments.

Eukaryotic initiation factor 5B: a new player for the anti-hepatitis C virus effect of ribavirin?

The addition of the broad-spectrum antiviral agent ribavirin (RBV), a synthetic guanosine analog, to interferon-alpha (IFNα) monotherapy has been a major breakthrough in the treatment of patients with hepatitis C virus (HCV), as it greatly improved treatment response rates. Although several mechanisms of action have been proposed for RBV's antiviral activity, each with some experimental evidence, the precise mechanism by which it acts synergistically with IFNα has remained elusive. A cornerstone of the antiviral IFNα response is phosphorylation of the α subunit of eukaryotic initiation factor (eIF)2. This limits the availability of eIF2⋅GTP⋅Met-tRNA(i)(Met) ternary complexes, reduces formation of the 43S preinitiation complexes, ultimately blocking viral (and most cellular) mRNA translation. However recent studies indicated that translation driven by the HCV internal ribosome entry site (IRES) is insensitive to eIF2α phosphorylation. Particularly, in addition to the general eIF2-dependent pathway of translation, the HCV IRES makes use of a bacterial-like, eIF2-independent pathway requiring as initiation factors only eIF5B (an analog of bacterial IF2) and eIF3. Together, these observations support a model in which cellular stresses that induce eIF2α phosphorylation (e.g. treatment with IFNα) cause HCV IRES-directed translation to switch from an eIF2-dependent mode to an eIF5B-dependent mode, defining a tactic used by HCV to evade the INFα response. Eukaryotic eIF5B is a ribosome-dependent GTPase that is responsible for 80S complex formation in translation initiation but shows much lower affinities for GTP than to other GTPases, thus suggesting that it may mis-incorporate the RBV triphosphate (RTP) in place of GTP even at the RBV concentrations achieved in clinical use. Consequently, we theorize that RTP bound to eIF5B lowering its affinity for ribosome, blocks the 80S complex formation on HCV IRES inhibiting the eIF5B-dependent translation used by HCV to elude IFNα response. In conclusion, our hypothesis provides a mechanistic explanation for the phenomenon of RBV enhancement in INFα-based therapy.

Treatment of patients with HCV related cirrhosis: many rewards with very few risks

Antiviral treatment of chronic hepatitis C virus (HCV) is aimed at the persistent eradication of the virus, the so-called sustained virological response (SVR), with the aim ultimately being to prevent the development of liver-related complications and improve patients' survival. Patients with HCV-related compensated cirrhosis are the group most likely to benefit from viral clearance, as several retrospective studies have shown liver complications rates to be positively modified by the achievement of a SVR. Whether these benefits rely on viral clearance or on the histological improvements seen following successful interferon (IFn)-based therapies has recently been a matter for debate, as studies have shown cirrhosis to regress in some patients with a SVR. Whatever the mechanisms, cirrhosis has the uncanny ability to be both a dominant indication for therapy, as well as one of the strongest baseline factors associated with reduced efficacy of any IFn-based regimen. This has led to the development of alternative treatment strategies, such as low dose pegylated IFn (PegIFn) monotherapy, that unfortunately has proven to be of limited efficacy. For this reason regimens able to clear the virus without relying on the broad antiviral effect of IFN are eagerly awaited.

Direct peptide bioconjugation/PEGylation at tyrosine with linear and branched polymeric diazonium salts

Direct polymer conjugation at peptide tyrosine residues is described. In this study Tyr residues of both leucine enkephalin and salmon calcitonin (sCT) were targeted using appropriate diazonium salt-terminated linear monomethoxy poly(ethylene glycol)s (mPEGs) and poly(mPEG) methacrylate prepared by atom transfer radical polymerization. Judicious choice of the reaction conditions-pH, stoichiometry, and chemical structure of diazonium salt-led to a high degree of site-specificity in the conjugation reaction, even in the presence of competitive peptide amino acid targets such as histidine, lysines, and N-terminal amine. In vitro studies showed that conjugation of mPEG(2000) to sCT did not affect the peptide's ability to increase intracellular cAMP induced in T47D human breast cancer cells bearing sCT receptors. Preliminary in vivo investigation showed preserved ability to reduce [Ca(2+)] plasma levels by mPEG(2000)-sCT conjugate in rat animal models.

The interferon-dependent orchestration of innate and adaptive immunity after transplantation

The therapeutic GVL effect after allogeneic stem cell transplantation is limited by the development of GVHD. The ultimate aim of current research is to separate the 2 processes in a meaningful fashion. The IFNs are a pleiotropic group of cytokines that were originally recognized because of their ability to interfere with viral replication. However, it is now established that these cytokines play an important role in orchestrating both innate and adaptive immunity. Multiple studies have investigated the effects of both types I and II IFN on GVHD and GVL in preclinical transplant models. The results indicate variable effects that are dependent on the period of activity within the developing immune response, the presence and type of pretransplant conditioning and the differential mechanisms, and IFN sensitivity of immune pathology within individual target organs during GVHD. This Perspective discusses the current literature on the IFNs and their potential modulation within clinical transplantation, focusing particularly on enhancing the therapeutic GVL effects.

Interferon-α as antiviral and antitumor vaccine adjuvants: mechanisms of action and response signature

Interferon-α (IFN-α) are cytokines endowed with multiple biologic effects, including activities on cells of the immune system, which are important for inducing protective antiviral and antitumor responses. Studies in mouse models have been instrumental for understanding the immune adjuvant activity of these cytokines and some of their mechanisms of action. In particular, recent studies conducted on both mouse and human models suggest that IFN-α act as effective immune adjuvants for inducing antiviral and antitumor immunity and that the effects of IFN on the differentiation and activation of dendritic cells (DC) play an important role in the induction of protective responses. In spite of the long record of IFN-α clinical use, a few clinical trials have attempted to evaluate the efficacy of these cytokines used as vaccine adjuvants. Recently, studies on the IFN-α signature in cells from patients treated with IFN-α under different modalities and various clinical settings have provided important insights for understanding the in vivo mechanisms of the IFN immune adjuvant activity in humans and may contribute to the identification of molecular markers with a clinical response. These studies further support the interest of evaluating the clinical efficacy of IFN-α when used as a vaccine adjuvant and also suggest that the DC generated in vitro from monocytes in the presence of this cytokine can exhibit a special advantage for the development of effective therapeutic vaccination strategies in cancer patients.

Hyporesponsiveness to PegIFNα2B plus ribavirin in patients with hepatitis C-related advanced fibrosis

BACKGROUND & AIMS

The success of pegylated-interferon (PegIFN)/ribavirin (Rbv) therapy of chronic hepatitis C is compromised by liver fibrosis. Whether fibrosis equally affects the two PegIFNα-based therapies is unknown. To assess the response to the two PegIFN regimens in patients with different degree of liver fibrosis.

METHODS

A sub-analysis of the MIST study: 431 consecutive naïve patients randomly assigned, based on HCV genotype, to receive either (A) PegIFNα2a 180 μg/wk plus daily Rbv 800-1200 mg or (B) PegIFNα2b 1.5 μg/kg/week plus daily Rbv 800-1200 mg, were stratified according to Ishak staging (S) into mild (S0-S2) or moderate (S3, S4) fibrosis and cirrhosis (S5, S6).

RESULTS

In A the sustained virological response (SVR) rates were not significantly influenced by fibrosis stage (71% in S0-S2, 66% in S3, S4, 53% in S5, S6, p=0.12), compared to B where the SVR rates differed according to fibrosis stage (65%, 46%, and 38%, p=0.004, respectively). This was even more so in HCV-1/4 patients treated with PegIFNα2b where the SVR rates were twice as many in S0-S2 vs. S≥3 (44% vs. 22%, p=0.02), while in A the SVR rates were similar between the two fibrosis subgroups (S0-S2: 47% vs. S≥3: 48%, p=0.8). By logistic regression analysis genotype 1/4 and lack of rapid virological response were independent predictors of treatment failure in both treatment groups, while S≥3 fibrosis was associated to PegIFNα2b treatment failure, only (OR 2.83, 95% CI 1.4-5.68, p=0.004).

CONCLUSIONS

Liver fibrosis was an independent moderator of treatment outcome in patients receiving PegIFNα2b, not in those receiving PegIFNα2a.

Sperm DNA damage in patients with chronic viral C hepatitis

INTRODUCTION

The aim of this study was to evaluate the conventional and biofunctional parameters of sperm in young infertile patients with Hepatitis C (HCV) infection.

METHODS

Forty HCV patients with primary infertility, aged 27 to 42 years (mean 36.4 years) and twenty HCV patients with secondary infertility aged 28 to 45 years (mean 35.0±2.8 years), underwent hormonal and sperm analysis in addition to the determination of reactive oxygen species (ROS) concentrations in the sperm and flow-cytometric evaluation. The following biofunctional sperm parameters were evaluated by flow cytometry: DNA fragmentation, mitochondrial membrane potential, chromatin condensation, and the rate of early apoptosis.

RESULTS

Overall, patients with HCV showed significantly worse median values of conventional and biofunctional sperm parameters than control subjects, including sperm density (31.7 vs. 80.4 million/ml), forward motility (9.4 vs. 25%), normal forms (15.4 vs. 24.8%), DNA fragmentation (6.6 vs. 2.2%), low MMP (45.5 vs. 8%), an early apoptosis rate (5 vs. 2.7%), and abnormal chromatin (18.9 vs. 13.9%). Finally, HCV patients had significantly higher basal (250 vs. 75×10(3)/cpm) and stimulated (550 vs. 120×10(3)/cpm) ROS levels in semen compared to control subjects. None of the examined parameters (sperm, hormonal, biofunctional and assessment of oxidative status in the semen) was significantly different between HCV patients with primary and secondary infertilities.

DISCUSSION

These results confirm that HCV infection has a negative impact on sperm parameters. The overlap of the results observed in the two groups of HCV patients supports the hypothesis that HCV infection may cause to alterations in sperm parameters.

Controlled-release interferon alpha 2b, a new member of the interferon family for the treatment of chronic hepatitis C

INTRODUCTION

Combination therapy with pegylated interferon alpha (Peg-interferon) and ribavirin is currently the cornerstone of antiviral therapy for chronic hepatitis C. Monotherapy with Peg-interferon still is important for the treatment of chronic hepatitis B. With the advent of new therapies, protease inhibitors for chronic hepatitis C and nucleotide inhibitors for chronic hepatitis B, there remains a need for interferon-based therapies. The side effects of Peg-interferon are a main disadvantage and represent a stumbling block for many patients to enter and continue therapy.

AREAS COVERED

In this review, the authors will discuss controlled-release interferon alpha 2b (CR2b) (Locteron®, Biolex Therapeutics, Pittsboro, NC, USA), a new slow-release interferon alpha 2b preparation for the treatment of chronic viral hepatitis. Other alternative interferons will also be discussed.

EXPERT OPINION

CR2b is a slow-release microsphere preparation for the administration of plant-derived recombinant human interferon alpha 2b. Compared with Peg-interferon, treatment with CR2b shows less flu-like reactions and less depression, and is at least as effective as conventional Peg-interferon-based therapy in patients with chronic hepatitis C. CR2b has the added advantage of biweekly instead of once weekly administration. CR2b appears to cause more neutropenia than Peg-interferon alpha 2b. This may be due to higher trough serum levels of CR2b at the end of a dosing interval. The bone marrow effects of CR2b closely resemble those published for the registered Peg-interferon alpha 2a. CR2b appears to have at least comparable efficacy with fewer side effects than current registered Peg-interferons.

Interferon-lambda and therapy for chronic hepatitis C virus infection

Interferon (IFN)-α, a type-I IFN, is widely used to treat chronic hepatitis C virus infection, but the broad expression of IFN-α receptors often leads to adverse reactions in many organs. Here, we examine IFN-λ, a type-III IFN, as a therapeutic alternative to IFN-α. Like IFN-α, IFN-λ also induces antiviral activity in hepatocytes, but might induce fewer adverse reactions because its receptor is largely restricted to cells of epithelial origin. We also discuss the recent discovery of single nucleotide polymorphisms (SNPs) near the human IFN-λ3 gene, IL28B, that correlate strongly with the ability to achieve a sustained virological response to therapy with pegylated IFN-α plus ribavirin in patients with chronic hepatitis C.

Impact of the autophagy machinery on hepatitis C virus infection

Autophagy is a cellular process that catabolizes cytoplasmic components and maintains energy homeostasis. As a stress response, the autophagy machinery interconnects a wide range of cellular pathways, enhancing the spread of certain pathogens while limiting others, and has become a highly active research area over the past several years. Independent laboratories have recently reported that autophagy vesicles accumulate in hepatitis C virus (HCV) infected cells and that autophagy proteins can function as proviral factors required for HCV replication. In this review, we summarize what is currently known about the interplay between autophagy and HCV and the possible mechanisms whereby autophagy proteins might favor HCV propagation.

Polymer therapeutics as nanomedicines: new perspectives

A growing number of polymer therapeutics have entered routine clinical use as nano-sized medicines. Early products were developed as anticancer agents, but treatments for a range of diseases and different routes of administration have followed--recently the PEGylated-anti-TNF Fab Cimzia® for rheumatoid arthritis and the PEG-aptamer Macugen® for age related macular degeneration. New polymer therapeutic concepts continue to emerge with a growing number of conjugates entering clinical development, for example PEGylated-aptamers and a polymer-based siRNA delivery system. 'Hot' topics of the past 2 years include; emerging issues relating to polymer safety, the increasing use of biodegradable polymers, design of technologies for combination therapy, potential biomarkers for patient individualisation of treatment and Regulatory challenges for 'follow-on/generic' polymer therapeutics.

Characteristics and PD-1 expression of peripheral CD4+CD127loCD25hiFoxP3+ Treg cells in chronic HCV infected-patients

Background

Both regulatory T cells (Tregs) and PD-1/PD-L1 pathway were critically involved in HCV viral persistence. However, the association between them was not well investigated. Herein, we aimed to investigate the distributional profiles of Tregs subsets and association between PD-1 expression on these subsets and development of HCV long-term persistence.

Methods

CD45RA and CD27 were employed to separate peripheral Tregs as naïve/central memory/effector memory/effector subsets. The phenotypic characteristics and PD-1 expression of Tregs were studied by flow cytometry.

Results

In the present study, the majority of Tregs was identified as central memory phenotype in chronic hepatitis C patients compared with nearly equal contribution of naïve and central memory subsets in healthy individuals. PD-1 expression was elevated in all CD4+ T cell subset in chronic HCV infected patients, including Tregs. Of note, higher level of PD-1 expression was found on TEM- and effector-Treg than naïve- and TCM-Tregs subsets. The ratio of TEM-Tregs/naive-Tregs and TEM-Tregs/TCM-Tregs regarding to PD-1 MFI were significantly lower in CHC patients compared to controls.

Conclusions

Our study indicated that distinctive characteristics of PD-1 expression on Tregs in HCV infection suggests associated with impaired adaptive immunity as well as viral long-term persistence. The cross talk between Treg cells and PD-1 induced inhibition in chronic HCV infection deserved further exploration for HCV infection associated immune pathogenesis.

A review of the treatment of chronic hepatitis C virus infection in cirrhosis

BACKGROUND

Cirrhosis developing during chronic infection with the hepatitis C virus (HCV) poses a risk of anticipated liver-related death, therefore representing a dominant indication to anti-HCV therapy.

OBJECTIVE

This review highlights the efficacy and safety of treatment of HCV infection in cirrhotic patients with respect to the clinical stage of the disease.

METHODS

The PubMed, MEDLINE, EMBASE, and Cochrane databases, as well as the conference proceedings from the annual meetings of the American Association for the Study of Liver Diseases, the European Association for the Study of the Liver, and the Asian Pacific Association for the Study of the Liver, were searched for articles published in English from January 1990 through May 2010, fulfilling the following criteria: (1) randomized, prospective observational, retrospective, or meta-analysis; (2) involving adult patients with chronic HCV infection; and (3) data (fibrosis stage, treatment regimen, efficacy, safety) available for cirrhotics. Reviews were excluded. Search terms included chronic hepatitis C, fibrosis, cirrhosis, interferon alfa, ribavirin, hepatocellular carcinoma, and liver decompensation.

RESULTS

Forty-five studies were identified. The rates of sustained virologic response to pegylated interferon in combination with ribavirin ranged from 10% to 44% for HCV genotypes 1/4 to 33% to 72% for genotypes 2/3 in compensated cirrhosis, while falling to 0% to 16% and 44% to 57%, respectively, in the decompensated stage, compared with 29% to 55% for genotypes 1/4 and 70% to 80% for genotypes 2/3 in noncirrhotic patients (compensated cirrhosis vs no cirrhosis: P < 0.001 for genotypes 1/4 and P = 0.002 for genotypes 2/3; decompensated cirrhosis vs no cirrhosis: P < 0.001 for all genotypes). HCV clearance was associated with a reduced risk of liver decompensation, hepatocellular carcinoma development, liver-related mortality, and hepatitis recurrence after liver transplantation. Treatment during compensated cirrhosis proved to be most cost-effective versus treatment after decompensation or a no-treatment strategy. Headache (54%), irritability (38%), fatigue (34%), and nausea (30%) were the most common adverse events in compensated patients, while anorexia (100%), fatigue (59%), neutropenia (53%), and thrombocytopenia (50%) were most common in decompensated patients.

CONCLUSIONS

Anti-HCV treatment in cirrhotic patients was less effective than in noncirrhotic patients. Viral eradication reduced the risk of liver complications and improved survival in noncirrhotics. Based on effectiveness and tolerability data, therapy has a significant effect in patients with compensated cirrhosis, while decompensated patients need to weigh the risks versus benefits of treatment.

Thyroid disease is a favorable prognostic factor in achieving sustained virologic response in chronic hepatitis C undergoing combination therapy: A nested case control study

BACKGROUND

Interferon-α in combination with ribavirin is the current gold standard for treatment of chronic hepatitis C. It is unknown if the development of autoimmune thyroid disease (TD) during treatment confers an improved chance of achieving sustained virologic response. The aim of this study is to assess the chance of achieving sustained virologic response (SVR) in patients who developed TD during treatment when compared with those who did not.

METHODS

We performed a tertiary hospital-based retrospective nested case-control analysis of 19 patients treated for hepatitis C who developed thyroid disease, and 76 controls (matched for age, weight, gender, cirrhosis and aminotransferase levels) who did not develop TD during treatment. Multivariate logistic-regression models were used to compare cases and controls.

RESULTS

The development of TD was associated with a high likelihood of achieving SVR (odds ratio, 6.0; 95% confidence interval, 1.5 to 24.6) for the pooled group containing all genotypes. The likelihood of achieving SVR was increased in individuals with genotype 1 HCV infection who developed TD (odds ratio, 5.2; 95% confidence interval, 1.2 to 22.3), and all genotype 3 patients who developed TD achieved SVR.

CONCLUSIONS

Development of TD during treatment for hepatitis C infection is associated with a significantly increased chance of achieving SVR. The pathophysiogical mechanisms for this observation remain to be determined.

TRIAL REGISTRATION

The Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRB12610000830099.

Concomitant detection of IFNα signature and activated monocyte/dendritic cell precursors in the peripheral blood of IFNα-treated subjects at early times after repeated local cytokine treatments

BACKGROUND

Interferons alpha (IFNα) are the cytokines most widely used in clinical medicine for the treatment of cancer and viral infections. Among the immunomodulatory activities possibly involved in their therapeutic efficacy, the importance of IFNα effects on dendritic cells (DC) differentiation and activation has been considered. Despite several studies exploiting microarray technology to characterize IFNα mechanisms of action, there is currently no consensus on the core signature of these cytokines in the peripheral blood of IFNα-treated individuals, as well as on the existence of blood genomic and proteomic markers of low-dose IFNα administered as a vaccine adjuvant.

METHODS

Gene profiling analysis with microarray was performed on PBMC isolated from melanoma patients and healthy individuals 24 hours after each repeated injection of low-dose IFNα, administered as vaccine adjuvant in two separate clinical trials. At the same time points, cytofluorimetric analysis was performed on CD14+ monocytes, to detect the phenotypic modifications exerted by IFNα on antigen presenting cells precursors.

RESULTS

An IFNα signature was consistently observed in both clinical settings 24 hours after each repeated administration of the cytokine. The observed modulation was transient, and did not reach a steady state level refractory to further stimulations. The molecular signature observed ex vivo largely matched the one detected in CD14+ monocytes exposed in vitro to IFNα, including the induction of CXCL10 at the transcriptional and protein level. Interestingly, IFNα ex vivo signature was paralleled by an increase in the percentage and expression of costimulatory molecules by circulating CD14+/CD16+ monocytes, indicated as natural precursors of DC in response to danger signals.

CONCLUSIONS

Our results provide new insights into the identification of a well defined molecular signature as biomarker of IFNα administered as immune adjuvants, and for the characterization of new molecular and cellular players, such as CXCL10 and CD14+/CD16+ cells, mediating and possibly predicting patient response to these cytokines.

Development of a novel DDS for site-specific PEGylated proteins

Because of the shifted focus in life science research from genome analyses to genetic and protein function analyses, we now know functions of numerous proteins. These analyses, including those of newly identified proteins, are expected to contribute to the identification of proteins of therapeutic value in various diseases. Consequently, pharmacoproteomic-based drug discovery and development of protein therapies attracted a great deal of attention in recent years. Clinical applications of most of these proteins are, however, limited because of their unexpectedly low therapeutic effects, resulting from the proteolytic degradation in vivo followed by rapid removal from the circulatory system. Therefore, frequent administration of excessively high dose of a protein is required to observe its therapeutic effect in vivo. This often results in impaired homeostasis in vivo and leads to severe adverse effects. To overcome these problems, we have devised a method for chemical modification of proteins with polyethylene glycol (PEGylation) and other water-soluble polymers. In addition, we have established a method for creating functional mutant proteins (muteins) with desired properties, and developed a site-specific polymer-conjugation method to further improve their therapeutic potency. In this review, we are introducing our original protein-drug innovation system mentioned above.