Evolutionary dynamics of hepatitis C virus NS3 protease domain during and following treatment with narlaprevir, a potent NS3 protease inhibitor.

Narlaprevir, a hepatitis C virus (HCV) NS3/4A serine protease inhibitor, has demonstrated robust antiviral activity in a placebo-controlled phase 1 study. To study evolutionary dynamics of resistant variants, the NS3 protease sequence was clonally analysed in thirty-two HCV genotype 1-infected patients following treatment with narlaprevir. Narlaprevir monotherapy was administered for one week (period 1) followed by narlaprevir/pegylated interferon-alpha-2b combination therapy with or without ritonavir (period 2) during two weeks, interrupted by a washout period of one month. Thereafter, all patients initiated pegylated interferon-alpha-2b/ribavirin combination therapy. Longitudinal clonal analysis was performed in those patients with NS3 mutations. After narlaprevir re-exposure, resistance-associated mutations at position V36, T54, R155 and A156 were detected in five patients in >95% of the clones. Narlaprevir retreatment resulted in a 2.58 and 5.06 log10 IU/mL viral load decline in patients with and without mutations, respectively (P=<0.01). After treatment, resistant variants were replaced with wild-type virus within 2-24 weeks in three patients. However, the R155K mutation was still observed 3.1 years after narlaprevir dosing in two patients in 5% and 45% of the viral population. Resistant variants could be detected early during treatment with narlaprevir. A slower viral load decline was observed in those patients with resistance-associated mutations detectable by direct population sequencing. These mutations disappeared within six months following treatment with the exception of R155K mutation, which persisted in two patients.

Chronic hepatitis E after solid organ transplantation.

Large outbreaks of acute hepatitis E, caused by hepatitis E virus (HEV) genotypes 1 and 2, are known from developing countries with suboptimal sanitation infrastructure. An increasing incidence of HEV infections is being reported in industrialised countries, caused mainly by HEV genotypes 3 and 4, which are often found among pigs. Recent evidence suggests that in immunocompromised patients about 50% of the cases of acute hepatitis E evolve to chronic hepatitis with rapid progression to cirrhosis. Thus, HEV should be considered a cause of chronic hepatitis in immunocompromised patients, such as solid organ transplant recipients. Because an antibody response to HEV may be absent in these patients, an HEV RNA test should be carried out when serum liver tests are elevated over months. In small case series, ribavirin has been shown to represent a promising treatment option for chronic HEV infection. To increase the awareness for HEV infection in immunocompromised patients, a representative case report of an HEV-infected renal transplant recipient with chronic hepatitis E, successfully treated with ribavirin, is presented. Studies are required to determine the optimal duration of ribavirin therapy and to assess outcome for solid organ transplant recipients with chronic HEV infection.

Genetic variation in IL28B and treatment outcome in HBeAg-positive and -negative chronic hepatitis B patients treated with Peg interferon alfa-2a and adefovir.

In a cohort of 95 chronic hepatitis B patients, who were treated with peg-interferon and adefovir for 1 year, and who had 15% HBsAg loss (overall), no association was found between IL28B polymorphisms and HBeAg seroconversion or HBsAg clearance. These findings suggest that any association with outcome, if present, is less than that seen in chronic hepatitis C. Additional studies are needed to enlarge sample size and to refine our understanding of IL28B biology in the context of chronic hepatitis B response to immunomodulatory and direct antiviral therapy.

Randomised clinical trial: escitalopram for the prevention of psychiatric adverse events during treatment with peginterferon-alfa-2a and ribavirin for chronic hepatitis C.

BACKGROUND Treatment of hepatitis C with peginterferon and ribavirin is associated with psychiatric side-effects, frequently necessitating dose reduction or therapy cessation. AIM To assess the efficacy of prophylactic escitalopram to prevent psychiatric side-effects during peginterferon and ribavirin treatment in a randomised, double-blind, placebo-controlled trial. METHODS Seventy-nine hepatitis C patients were treated with peginterferon and ribavirin. Patients received escitalopram (n = 40, 10 mg) or placebo (n = 39), which was initiated together with peginterferon and ribavirin. Primary outcomes were an increase of two points or more on the items reported sadness, inner tension and impaired concentration of the Montgomery-Asberg Depression Rating Scale, and hostile feelings of the Brief Anxiety Scale. Secondary outcome was the development of depression diagnosed by the Mini-International Neuropsychiatric Interview. Measurements were performed at baseline, week 4, 12 and 24 during anti-viral treatment, and 24 weeks thereafter. RESULTS The incidence of psychiatric side-effects was significantly lower in patients treated with escitalopram compared with placebo for all primary and secondary outcomes, except for impaired concentration: reported sadness 27.5 vs. 48.7% (P = 0.052), inner tension 17.5 vs. 38.5% (P = 0.038), impaired concentration 55.0 vs. 66.7% (P = 0.288) and hostile feelings 22.5 vs. 43.6% (P = 0.046) (escitalopram vs. placebo, Chi-squared test). The sum scores of all four endpoints showed an overall beneficial effect of escitalopram (P = 0.009, Mann-Whitney U-test). Depression occurred in 12.5% of the patients in the escitalopram-group vs. 35.9% in the placebo-group (P = 0.015, Chi-squared test). CONCLUSIONS Prophylactic treatment with escitalopram is effective in the prevention of psychiatric side-effects during interferon-based treatment of hepatitis C.

Randomised clinical trial: anti-viral activity of ANA773, an oral inducer of endogenous interferons acting via TLR7, in chronic HCV.

BACKGROUND: The ANA773 is an oral prodrug of a small-molecule toll-like receptor (TLR)7 agonist. Preclinical and healthy volunteer clinical studies with ANA773 have demonstrated induction of endogenous interferon-α (IFN-α) of multiple subtypes, which supports the potential utility in the treatment of chronic hepatitis C virus (HCV) infection. AIM: To examine safety, tolerability, pharmacodynamics, pharmacokinetics and anti-viral activity of ANA773. METHODS: The ANA773 was investigated in a double-blind, placebo-controlled study in 34 patients chronically infected with HCV of any genotype. Patients were treatment-naïve or had relapsed following previous interferon-based treatment. This dose escalation study was composed of four dose groups (800, 1200, 1600 and 2000mg). In each group, six to eight patients received ANA773 and two received placebo. Patients were dosed with ANA773 every-other-day for either 28 days (800, 1200 or 1600mg) or 10days (2000mg). RESULTS: Mild to moderate adverse events were reported, with an increase in frequency and intensity with increasing dose. No serious AEs were reported and there were no early discontinuations. There were dose-related increases in various markers of IFN-α response. The mean maximum change in serum HCV RNA level from baseline was -0.34, -0.29, -0.40, -0.97 and -1.26log(10) in the placebo, 800, 1200, 1600 and 2000mg cohorts, respectively. At the 2000mg dose, ANA773 significantly (P=0.037) reduced serum HCV RNA levels (range: 0.14 to -3.10log(10) ). CONCLUSION: The ANA773 was generally well tolerated and resulted in a dose-related IFN-dependent response leading to a significant decrease in serum HCV RNA levels in the 2000mg dose group.

Evaluation of a risk assessment questionnaire to assist hepatitis C screening in the general population.

Many individuals with hepatitis C virus (HCV) infection are undiagnosed. This study evaluates a risk assessment questionnaire, developed for use online to target blood-screening for HCV. Two hundred and eighty-nine patients with known HCV status completed a written questionnaire on prominent HCV risk factors. Questionnaires generated advice to seek testing if at least one risk factor was reported. Agreement of the testing advice with the HCV status of respondents was evaluated. Subsequently, we validated our questionnaire among 985 patients of an outpatient clinic for sexually transmitted infections. The post-test-probability-of-disease (PTPD) and diagnostic gain (PTPD minus prior probability of disease) were calculated. The questionnaire's sensitivity and specificity were 84.6% and 63.8%, respectively, and higher in the STI clinic patients. The PTPD of positive testing advice was 72.5% given HCV prevalence of 53.0%, yielding a diagnostic gain of 19.5%. Applying the estimated prevalence in the general Dutch population (0.1-0.4%), and the anticipated prevalence in the online project (1.0-6.0%), yielded diagnostic gains of 0.13-0.53% and 1.3-7.0%, respectively. We conclude that our questionnaire succeeded in selecting at-risk individuals as its testing advice agreed well with the HCV status. We suggest that the questionnaire be used online as a selection tool for HCV blood-screening in the general population.

New developments in antiviral therapy for chronic hepatitis B.

Chronic hepatitis B affects approximately 400 million people in the world with a substantial disease burden like liver cirrhosis and hepatocellular carcinoma (HCC). Treatment for chronic hepatitis B has improved dramatically in the last decade, resulting in more patients achieving a state of inactive disease. Currently two treatment strategies are available; treatment with peginterferon (peg-IFN) or nucleos(t)ide analogues with the aim to suppress hepatitis B virus (HBV) DNA to subsequently avoid the development of cirrhosis and HCC. Unfortunately, treatment with peg-IFN can be suboptimal with important adverse effects and nucleos(t)ide analogues provoke resistance. At present, no new promising compounds attacking the HBV life cycle are in development. However, for prediction of sustained response or treatment failure, data from the long-term large peg-IFN trials provide important response markers. For the future the focus is to achieve HBsAg loss and anti-HBs conversion which is the closest the treatment can get to a cure. This review summarizes the current treatment options with their response rates and discusses future strategies for chronic hepatitis B treatment.

Validation of a sensitive and specific real-time PCR for detection and quantitation of hepatitis B virus covalently closed circular DNA in plasma of chronic hepatitis B patients.

Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) serves as a template for viral replication and plays a role in persistence of HBV infection. The origin and significance of cccDNA in plasma however, is not well understood. A sensitive, specific, and reproducible real-time PCR for detection and quantitation of cccDNA in plasma of chronic hepatitis B patients was developed and validated. Four HBV DNA reference panels, and 96 plasma samples of chronic hepatitis B patients were analyzed. Results were compared with total HBV DNA levels, individual ALT levels and the Histology Activity Index (HAI). This cccDNA assay had a lower limit of detection at 15 copies/PCR, a lower limit of quantitation at 91 copies/PCR and a correlation coefficient (R) of 0.98 (P < 0.0001). cccDNA was detected in two of four international panels. Significant correlation was found between cccDNA and total HBV DNA levels in both panels (R = 0.96, and R = 0.43) and in samples of the chronic hepatitis B patients (R = 0.88, P < 0.0001). In 57% of these samples cccDNA was detectable. Mean level of cccDNA was 0.16% of total HBV load. Plasma cccDNA levels were higher in HBeAg positive samples than in HBeAg negative samples (4.91 log copies/ml vs. 3.88 log copies/ml, P < 0.0001). Levels of total HBV DNA and HBV genotype did not influence cccDNA detection. ALT levels and HAI-score were not correlated with plasma cccDNA levels. These findings suggest that cccDNA levels in plasma are not the result of increased hepatocyte degeneration, but indicate that other mechanisms might be responsible.

New developments in the antiviral treatment of hepatitis C.

Chronic hepatitis C virus (HCV) infection is a major cause of liver cirrhosis and hepatocellular carcinoma. HCV is endemic in most parts of the world, with an estimated 170 million people infected worldwide and 3-4 million new cases each year. HCV-related end-stage liver disease is now the main indication for liver transplantation in the USA and Western Europe. Unfortunately, no vaccine or immunoglobulin is available to prevent HCV infection. Currently, HCV treatment consists of the combined administration of pegylated interferon and ribavirin for a period of 24-48 weeks, resulting in complete viral eradication in 40-80% of patients, depending on genotype, viral load and patient characteristics. This therapy is often accompanied with side-effects that affect compliance and reduce treatment outcomes. Recently, reliable in vitro culture systems have been developed which accelerated antiviral therapy research. Many new specifically targeted antiviral therapies for hepatitis C (STAT-C) and treatment strategies are evaluated in clinical trials. These new antiviral agents are expected to improve treatment significantly with potentially shorter treatment duration. The most promising antiviral agents will be reviewed.

Susceptibility of hepatitis B virus to lamivudine restored by resistance to adefovir.

Serial monotherapy and add-on regimes for treatment of chronic hepatitis B virus (HBV) infection may induce the accumulation of viral resistance mutations in patients, reducing the options for ongoing viral suppression. The induction of antiviral resistance by serial application of polymerase inhibitors does not necessarily imply that the subsequent combined use of the drugs will fail. Some HIV strains resistant to one polymerase inhibitor show increased susceptibility to another polymerase inhibitor. After failure of sequential lamivudine and adefovir monotherapy, two patients with hepatitis B changed to treatment with lamivudine plus adefovir and had renewed suppression of HBV. To study the mutational history of resistant HBV subpopulations in the two patients, a part of the HBV polymerase gene was amplified, cloned, sequenced, and analyzed for the presence of mutations, in sequential plasma samples. In both patients serial monotherapy caused the replacement in all HBV clones of wild-type virus by classical lamivudine resistant mutants (L180M and M204V/I), which were replaced subsequently by adefovir resistant mutants (A181V and N236T). When finally lamivudine was added to adefovir, the A181V adefovir mutation persisted in all clones and lamivudine-related mutations did not reappear. During 18 months of combination therapy, HBV-DNA levels decreased 10,000, respectively, 1,000-fold, despite the earlier resistance to lamivudine and adefovir. Although clinically insufficient, this effect indicates that HBV polymerase resistance mutations may be antagonistic, which is relevant if chronic HBV infection is to be treated by a combination of polymerase inhibitors.

[Hepatitis C in the Netherlands: sparse data on the current prevalence and the necessity for epidemiological studies and innovative methods for detecting infected individuals]. / Hepatitis C in Nederland: schaarse gegevens over actuele prevalentie en de noodzaak van epidemiologisch onderzoek en innovatieve opsporingsmethoden.

Hepatitis C is a blood-borne virus infection with an estimated 180 million infected individuals worldwide. Hepatitis C virus (HCV) infection may lead to liver failure and cancer of the liver. In 2004, in view of the improved treatment options, the Dutch Health Council again recommended that the groups at risk of HCV infection should be tracked down and informed, and that epidemiological studies should be conducted. Currently, there are few data on the prevalence of HCV infection in the Netherlands. HCV risk groups are (former) injecting drug users, haemodialysis patients and haemophiliacs, people treated with blood or blood products before 1992, people who have undergone certain invasive or medical procedures with insufficiently sterilised instruments, household contacts and partners of HCV-infected individuals and children born to HCV-infected mothers. Insight into the epidemiology of HCV infection in the Netherlands is necessary so that reliable estimates of the magnitude of hepatitis C as a public health problem can be made. Several projects for the detection of HCV infected individuals and epidemiological studies have started in 2007.

[The treatment of chronic hepatitis C virus infection in children]. / De behandeling van kinderen met chronische hepatitis C.

A 9-year-old boy, a 15-year-old boy, and a 6-year-old girl were infected with chronic hepatitis C virus (HCV). They had no physical complaints and a virus genotype that was favourable to treatment with peginterferon-alpha and ribavirin. The younger boy and the girl had liver fibrosis and were treated for 6 months; the virus was eradicated from the boy's plasma and the fibrosis diminished, while the girl's plasma virus was again present shortly after the end of treatment. In the older boy with no fibrosis, treatment was temporarily suspended due to behaviour problems. HCV infection is a frequent cause of chronic hepatitis in children. A better understanding of its natural history, improvements in the efficacy of treatment, and more favourable outcomes seen in children compared with adults have gradually changed the consideration to treat children with chronic HCV infection over the last 10 years. The decision whether or not to treat depends primarily on the degree of liver damage, virus genotype, and the psychological condition and motivation of the patient. Screening patients at risk for chronic HCV infection and careful follow-up for liver damage in those with HCV infection have become even more important given the new insights regarding treatment.

Chronic hepatitis C patients with a post-treatment virological relapse re-treated with an induction dose of 18 MU interferon-alpha in combination with ribavirin and amantadine: a two-arm randomized pilot study.

Thirty-seven chronic hepatitis C patients with virological relapse (VR) after previous interferon-alpha (IFN) or IFN/ribavirin (Riba) therapy, were re-treated. Patients were randomized for either IFN/Riba and amantadine (Ama) including a 2-week initial high IFN induction course (18 MU IFN daily) (group A) or the same 2-week IFN induction course combined with Riba/Ama, followed by Riba/Ama without IFN (group B). Treatment duration for both groups was 24 weeks with a 24-week follow-up thereafter. The inclusion in group B was prematurely stopped because all patients (n = 10) relapsed within 2 weeks after stopping IFN. Therefore, all subsequent patients were included in group A (n = 27). In group A, 44% achieved a sustained virological response (SVR) and 29% of the patients with an end-of-treatment virological response had a VR again. Of all pretreatment characteristics, only genotype non-1 patients had a significantly higher chance of achieving SVR (P < 0.001). Of the characteristics during treatment only a negative hepatitis C virus (HCV)-RNA test result in transcription-mediated amplification (TMA) at week 6 had a high predictive value for SVR, 80% in all patients and 92% in genotype non-1 patients. In conclusion, hepatitis C patients with a VR to previous antiviral treatment can be successfully re-treated with IFN induction combined with Riba/Ama for only 6 months, when they have genotype non-1 and a negative HCV-RNA test result in TMA 6 weeks after the start of therapy. Riba/Ama combination therapy without IFN does not prevent VR after 2 weeks high IFN induction.

Sustained virological response in chronic hepatitis C patients after a 6- and a 36-month interferon-alpha2b treatment schedule: a multicenter, randomized, controlled study.

BACKGROUND: In patients with chronic hepatitis C (HCV) Interferon-alpha (IFN) treatment for 12-18 months is more effective than 6 months in inducing a sustained virological response. METHODS: In a multicenter, randomized, controlled trial, 88 patients with chronic HCV were enrolled (47 treated with IFN-alpha2b and 41 constituted an untreated control group). Treatment consisted of 5 million units (MU) IFN thrice a week (tiw) for 8 weeks and subsequently 2.5 MU IFN tiw for 16 weeks ('standard treatment'). After week 24 ('long-term treatment'), in virological non-responders treatment was continued using 5 MU IFN tiw for up to week 156, whereas in virological responders IFN was discontinued. In case of a virological relapse, treatment with 5 MU IFN tiw was restarted and continued up to week 156. RESULTS: Sustained virological response rate was 6/47 (13%) after standard treatment and increased to 19/47 (40%) after long-term treatment (McNemar paired test; P = 0.002). Of the 18 patients with a breakthrough or relapse during or after standard treatment, 14 (78%) became sustained virological responders upon long-term treatment. Of the 4 patients who did not have a sustained virological response after long-term treatment, 3 did not receive complete treatment due to side effects and/or non-compliance. In patients who failed to respond to standard treatment, no virological response was observed during long-term treatment. In the control group, no spontaneous clearance of HCV was observed. CONCLUSIONS: Long-term IFN (re)treatment enhanced the virological sustained response rate significantly and was particularly effective in patients with a breakthrough or relapse following standard treatment.

Sexual transmission of hepatitis C virus.

We tested 50 heterosexual partners of hepatitis C viraemic (HCV) individuals, using second generation HCV antibody assays and a validated polymerase chain reaction assay. In none of them were HCV antibodies or HCV-RNA detected. The median duration of the sexual relationship was 13 years. This study, with the most sensitive techniques for detection of HCV, indicates that the risk of sexual transmission of HCV is absent or very low.