Randomized, double-blind, placebo-controlled trial of interferon alfa2a with and without amantadine as initial treatment for chronic hepatitis C

An updated systematic review and meta-analysis on efficacy of Sofosbuvir in treating hepatitis C-infected patients with advanced chronic kidney disease

Sofosbuvir seems to be a revolutionary treatment for Hepatitis C-infected patients with advanced chronic kidney disease (CKD) but existing evidence is not quite adequate. The aim of this study was to evaluate the efficacy and safety of Sofosbuvir-based therapy without Ribavirin for all hepatitis C virus genotypes among patients with advanced CKD. We conducted an updated systematic literature search from the beginning of 2013 up to June 2020. Sustained virologic response (SVR) rate at 12 and/or 24 weeks after the end of treatment, and adverse events in HCV-infected patients with advanced CKD were pooled using random effects models. We included 27 published articles in our meta-analyses, totaling 1,464 HCV-infected patients with advanced CKD. We found a substantial heterogeneity based on the I2 index (P = 0.00, I2 = 56.1%). The pooled SVR rates at 12 and 24 weeks after the end of Sofosbuvir-based treatment were 97% (95% Confidence Interval: 95-99) and 95% (89-99) respectively. The pooled SVR12 rates were 98% (96-100) and 94% (90-97) in patients under 60 and over 60 years old respectively. The pooled incidence of severe adverse events was 0.11 (0.04-0.19). The pooled SVR12 rate after completion of the half dose regimen was as high as the full dose treatment but it was associated with less adverse events (0.06 versus 0.14). The pooled SVR12 rate was 98% (91-100) in cirrhotic patients and 100% (98-100) in non-cirrhotic patients. The endorsement of Sofosbuvir-based regimen can improve the treatment of hepatitis C virus infection in patients with advanced CKD.

Sofosbuvir-based treatment is safe and effective in Indian hepatitis C patients on maintenance haemodialysis: A retrospective study

AIM

This study evaluates the safety and efficacy of direct-acting antivirals (DAAs) including sofosbuvir, ledipasvir and daclatasvir in patients with hepatitis C viraemia who were on maintenance haemodialysis.

METHODS

Data on patients who received sofosbuvir and ribavirin were analysed. Patients who experienced treatment failure with the above regimen received sofosbuvir and ledipasvir for infection with hepatitis C virus (HCV) genotype 1. Those having HCV genotype 3 infection received sofosbuvir and daclatasvir. All treatment regimens were of 12 weeks duration. Side-effects were investigated. The HCV viral load was determined by RT-PCR at 4,16 and 24 weeks after the initiation of therapy; haemoglobin levels and liver function tests were monitored at regular intervals during therapy.

RESULTS

Of the 22 subjects initially treated with sofosbuvir and ribavirin, 72.72% attained sustained virologic response at 12 weeks (SVR12). Four patients experienced treatment failure and received genotype specific therapy. Patients with HCV genotype one received sofosbuvir with ledipasvir. One patient with HCV genotype 3 infection received sofosbuvir and daclatasvir. All of them attained SVR12. A statistically significant reduction in the median serum glutamic-oxaloacetic transaminase (SGOT) and Serum glutamic pyruvic transaminase (SGPT) were observed from the baseline until the end of treatment. Anaemia was observed in 45% of patients receiving ribavirin.

CONCLUSIONS

Our study demonstrates that sofosbuvir-based therapy is efficacious for HCV viraemia in patients on maintenance haemodialysis. The therapy was found to be reasonably safe with no major adverse effects noted with the use of sofosbuvir, ledipasvir or daclatasvir. However, larger studies are needed to validate our results.

Amantadine and rimantadine for influenza A in children and the elderly

BACKGROUND

Influenza is an acute respiratory illness caused by influenza A and B viruses. Complications may occur, especially among children and the elderly.

OBJECTIVES

To assess the effectiveness and safety of amantadine and rimantadine in preventing, treating and shortening the duration of influenza A in children and the elderly.

SEARCH METHODS

We searched CENTRAL (2014, Issue 9), MEDLINE (1966 to September week 4, 2014) and EMBASE (1980 to October 2014).

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-RCTs comparing amantadine and/or rimantadine with no intervention, placebo, other antivirals or different doses or schedules of amantadine or rimantadine in children and the elderly with influenza A.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the search results. We extracted and analysed data using the standard Cochrane methodology.

MAIN RESULTS

We identified 12 studies (2494 participants: 1586 children and 908 elderly) comparing amantadine and rimantadine with placebo, paracetamol (one trial: 69 children) or zanamivir (two trials: 545 elderly) to treat influenza A.Amantadine was effective in preventing influenza A in children (773 participants, risk ratio (RR) 0.11; 95% confidence interval (CI) 0.04 to 0.30). The assumed risk of influenza A in the control group was 10 per 100. The corresponding risk in the rimantadine group was one per 100 (95% CI 0 to 3). Nevertheless, the quality of the evidence was low and the safety of the drug was not well established.For treatment, rimantadine was beneficial in abating fever on day three of treatment in children: one selected study with low risk of bias, moderate evidence quality and 69 participants (RR 0.36; 95% CI 0.14 to 0.91). The assumed risk was 38 per 100. The corresponding risk in the rimantadine group was 14 per 100 (95% CI 5 to 34).Rimantadine did not show any prophylactic effect in the elderly. The quality of evidence was very low: 103 participants (RR 0.45; 95% CI 0.14 to 1.41). The assumed risk was 17 per 100. The corresponding risk in the rimantadine group was 7 per 100 (95% CI 2 to 23).There was no evidence of adverse effects caused by treatment with amantadine or rimantadine.We found no studies assessing amantadine in the elderly.

AUTHORS' CONCLUSIONS

The quality of the evidence combined with a lack of knowledge about the safety of amantadine and the limited benefits of rimantadine, do not indicate that amantadine and rimantadine compared to control (placebo or paracetamol) could be useful in preventing, treating and shortening the duration of influenza A in children and the elderly.

Aminoadamantanes for chronic hepatitis C

BACKGROUND

Around 3% of the world's population (approximately 160 million people) are chronically infected with hepatitis C virus. The proportion of infected people who develop clinical symptoms varies between 5% and 40%. Combination therapy with pegylated interferon-alpha plus ribavirin eradicates the virus from the blood six months after treatment (sustained virological response) in approximately 40% to 80% of infected patients, depending on the viral genotype. New antiviral agents, such as boceprevir and telaprevir, in combination with standard therapy, can increase sustained virological response in genotype 1 infected patients to at least 70%. There is therefore an unmet need for drugs that can achieve a higher proportion of sustained virological response. Aminoadamantanes are antiviral drugs used for treatment of patients with chronic hepatitis C.

OBJECTIVES

To assess the beneficial and harmful effects of aminoadamantanes for patients with chronic hepatitis C infection by conducting a systematic review with meta-analyses of randomised clinical trials, as well as trial sequential analyses.

SEARCH METHODS

We conducted electronic searches of the Cochrane Hepato-Biliary Group Controlled Trials Register (1996 to December 2013), the Cochrane Central Register of Controlled Trials (CENTRAL) 2013, Issue 11 of 12 (1995 to December 2013), MEDLINE (1946 to December 2013), EMBASE (1974 to December 2013), Science Citation Index EXPANDED (1900 to December 2013), the WHO International Clinical Trials Registry Platform (www.who.int/ictrp), Google Scholar, and Eudrapharm up to December 2013 and checked the reference lists of identified publications.

SELECTION CRITERIA

Randomised clinical trials assessing aminoadamantanes in patients with chronic hepatitis C infection.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data. We assessed for risks of systematic errors ('bias') using the 'Risk of bias' tool. We analysed dichotomous data with risk ratio (RR) and continuous data with mean difference (MD) or standardised mean difference (SMD), both with 95% confidence intervals (CI). We used trial sequential analysis to assess the risk of random errors ('play of chance'). We assessed quality using the GRADE system.

MAIN RESULTS

We included 41 randomised clinical trials with 6193 patients with chronic hepatitis C. All trials had high risk of bias. All included trials compared amantadine versus placebo or no intervention. Standard antiviral therapy was administered equally to the intervention and the control groups in 40 trials. The standard antiviral therapy, which was administered to both intervention groups, was interferon-alpha, interferon-alpha plus ribavirin, and peg interferon-alpha plus ribavirin, depending on the time when the trial was conducted.When we meta-analysed all trials together, the overall results demonstrated no significant effects of amantadine, when compared with placebo or no intervention, on our all-cause mortality or liver-related morbidity composite outcome (5/2353 (0.2%) versus 6/2264 (0.3%); RR 0.90, 95% CI 0.38 to 2.17; I² = 0%; 32 trials; very low quality). There was also no significant effect on adverse events (288/2869 (10%) versus 293/2777 (11%); RR 0.98, 95% CI 0.84 to 1.14; I² = 0%; 35 trials; moderate quality). We used both fixed-effect and random-effects meta-analyses. Amantadine, when compared with placebo or no intervention, did not significantly influence the number of patients who failed to achieve a sustained virological response (1821/2861 (64%) versus 1737/2721 (64%); RR 0.98, 95% CI 0.95 to 1.02; I² = 35%; 35 trials; moderate quality). However, in the subgroup using interferon plus ribavirin, amantadine decreased the number of patients who failed to achieve a sustained virological response (422/666 (63%) versus 447/628 (71%); RR 0.89, 95% CI 0.83 to 0.96; I² = 41%; 11 trials; low quality). Similar results were found for failure to achieve an end of treatment virological response. Amantadine, when compared with placebo or no intervention, significantly decreased the number of patients without normalisation of alanine aminotransferase (ALT) serum levels at the end of treatment (671/1141 (59%) versus 732/1100 (67%); RR 0.88, 95% CI 0.83 to 0.94; I² = 47%; 19 trials; low quality). Amantadine, when compared with placebo or no intervention, did not significantly influence the end of follow-up biochemical response (1133/1896 (60%) versus 1151/1848 (62%); RR 0.95, 95% CI 0.91 to 1.00; I² = 49%; 21 trials; low quality).The observed beneficial effects could be true effects but could also be due to both systematic errors (bias) and random errors (play of chance). The latter is due to the fact that trial sequential analyses could not confirm or refute our findings. We were not able to perform meta-analyses for failure of histological improvement or quality of life due to a lack of valid data.

AUTHORS' CONCLUSIONS

This systematic review does not demonstrate any significant effects of amantadine on all-cause mortality or liver-related morbidity composite outcome and on adverse events in patients with hepatitis C; however, the median trial duration was 12 months, with a median follow-up of six months, which is not long enough to assess the composite outcome sufficiently. Overall, we did not see an effect of amantadine on failure to achieve a sustained virological response. Subgroup analyses demonstrated that the combination of amantadine plus interferon-alpha and ribavirin seems to increase the number of patients achieving a sustained virological response. This finding may be caused by both systematic errors (bias) and risks of random errors (play of chance), but it could also be real. Based on the results of the overall evidence, it appears less likely that future trials assessing amantadine for patients with chronic hepatitis C will show strong benefits. Therefore, it is probably advisable to wait for the results of trials assessing other direct-acting antiviral drugs. In the absence of convincing evidence of benefit, the use of amantadine is justified in the context of randomised clinical trials assessing the effects of combination therapy. We found a lack of evidence on other aminoadamantanes than amantadine.

Long-term viral negativity after interferon for chronic hepatitis C virus infection in hemodialysis

BACKGROUND AND OBJECTIVES

Interferon (IFN) and pegylated-IFN treatment of hepatitis C virus (HCV) infection in hemodialysis patients result in sustained virological response (SVR) rates of 45% and 37%, respectively. Although most nonhemodialysis patients who achieve SVR remain persistently viral negative, the durability of SVR in hemodialysis patients is unknown. We analyzed the rate of long-term virological negativity in hemodialysis patients who achieved SVR after IFN or pegylated-IFN through analysis of patient-level data.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

After performing a systematic literature review for IFN-based treatment of hemodialysis patients with chronic HCV infection, we extracted patient-level data on patients who achieved SVR. We performed life table analysis to estimate long-term virological negativity rates after SVR in patients who continued on hemodialysis or subsequently underwent kidney transplantation.

RESULTS

Long-term HCV RNA outcomes following SVR were available for 121 hemodialysis patients (20 studies) and 45 patients who subsequently underwent transplantation (11 studies). The probability of remaining HCV RNA negative was 86% (95% confidence interval, 77% to 96%) for patients followed on hemodialysis 48 months after SVR and 95% (95% confidence interval, 89% to 100%) for kidney recipients followed 48 months after transplant.

CONCLUSIONS

Viral negativity from IFN-based HCV treatment in hemodialysis patient appears durable during extended follow-up, including after kidney transplantation. The certainty of the viral negativity estimate is limited by the small number with follow-up beyond 48 months or longer. Transplantation does not confer an increased risk of relapse. Future research should investigate whether IFN-based treatment improves clinical outcomes for hemodialysis patients.

Influence of amantadine on CD81 expression on lymphocytes in chronic hepatitis C

INTRODUCTION

Interferon alpha (IFN) down regulates CD81 expression on peripheral blood mononuclear cells (PBMC) in patients with chronic hepatitis C virus (HCV) infection. Aim of our study was to investigate whether amantadine alters IFN associated down regulation of CD81 expression on PBMC in patients with chronic hepatitis C.

METHODS

Nineteen patients with chronic HCV infection received peginterferon alpha-2a/ribavirin (SOC) for 48 weeks. Patients were randomised to 12 weeks amantadine therapy (n=12) or no additional treatment (n=7). FACS analysis of CD81 expression on CD4(+), CD8(+), CD19(+), and CD56(+) cells was performed at baseline, week (TW) 4, TW12, and TW24 of antiviral therapy.

RESULTS

A significant decline of CD81 expression was observed on CD4(+), CD8(+), and CD56(+) cells (p=0.011, p<0.001, p=0.015, respectively) but not on CD19(+) cells (p>0.2). CD81 expression on CD4(+), CD8(+), CD19(+), and CD56(+) cells was not different between patients treated with SOC plus amantadine and patients treated with SOC alone.

CONCLUSION

The current study confirms that CD81 expression is down regulated by SOC on CD4(+), CD8(+) and CD56(+) cells. Amantadine treatment was not associated with CD81 expression. Interaction between amantadine and CD81 is unlikely to be involved in potential antiviral activity of amantadine in chronic HCV infection.

Clinical trial: a randomized trial of pegylated-interferon-alpha-2a plus ribavirin with or without amantadine in treatment-naïve or relapsing chronic hepatitis C patients

BACKGROUND

The combination therapy of pegylated-interferon-alpha2a plus ribavirin is considered as the standard of care for patients with chronic hepatitis C. A sustained viral response is obtained in 40-50% of naïve patients with genotype 1 and in around 80% of naïve patients with genotype 2 or 3.

AIM

To assess whether amantadine, added to the conventional combination therapy, could improve the treatment efficacy.

METHODS

In all, 630 patients (intent-to-treat population) with chronic hepatitis C were randomized into two groups: 316 patients (treatment group) received pegylated-interferon-alpha2a (180 microg once weekly) plus ribavirin (1000-1200 mg/daily) with amantadine (200 mg/daily); 314 patients (control group) received pegylated-interferon-alpha2a (180 microg once weekly) plus ribavirin (1000-1200 mg/daily) without amantadine. The duration of the treatment was 48 weeks for genotypes 1, 4, 5 and 6, and 24 weeks for genotypes 2 and 3.

RESULTS

There was no statistically significant difference between treatments groups for any of the variables tested for. Subgroups of patients likely to take advantage of the addition of amantadine were not identified.

CONCLUSIONS

This large study definitely excludes the role of amantadine in addition of conventional combination therapy in the treatment of chronic hepatitis C patients.

Novel interferons for treatment of hepatitis C virus

The current standard of care for treatment of hepatitis C is pegylated interferon and ribavirin. Despite the large number of new oral agents under development, interferon will likely remain the backbone of future therapy. Interferon has unique antiviral and immunomodulatory properties, which have been critical in limiting resistance to protease inhibitors and improving efficacy. Hence, optimizing pharmacokinetics and promoting adherence to interferon dosing regimens will become even more critical as new regimens enter the clinical arena. This review highlights novel interferons under development that may offer therapeutic advantages over the formulations currently available.

Interferon for hepatitis C virus in hemodialysis--an individual patient meta-analysis of factors associated with sustained virological response

BACKGROUND AND OBJECTIVES

Hepatitis C virus (HCV) infection is prevalent in hemodialysis patients and causes excess mortality. Interferon (IFN) treatment of chronic HCV infection in hemodialysis patients results in high sustained virological response (SVR) rates 6 mo after treatment. The authors aimed to identify factors associated with SVR in hemodialysis patients through analysis of individual patient data obtained from systematic review of published literature.

DESIGN, SETTING, PARTICIPANTS & MEASUREMENTS

Medline was searched from 1966 through February 2009, and prospective studies describing IFN treatment of hemodialysis patients with chronic HCV infection with published individual patient data were included. To identify factors associated with SVR, logistic regression was applied with adjustment for study.

RESULTS

Twenty studies of IFN treatment provided data on 428 patients. Overall SVR was 45% and in univariate analyses was higher with: 1) three million units or higher three times weekly of IFN; 2) treatment for at least 6 mo; 3) treatment completion; 4) lower baseline HCV RNA; 5) female gender; and 6) early virological negativity. Although limited by missing data, these relationships persisted in multivariate regression.

CONCLUSIONS

SVR is more likely with larger IFN dose, longer treatment duration, treatment completion, female gender, lower HCV RNA and early virological negativity. For appropriate treatment candidates, regimens should consist of three million units of IFN three times weekly for at least 6 mo, with patients encouraged to complete the full course.

Hepatitis C infection and chronic renal diseases

More than 170 million people worldwide are chronically infected with the hepatitis C virus (HCV), which is responsible for over 1 million deaths resulting from cirrhosis and liver cancers. Extrahepatic manifestations are also relevant and include mixed cryoglobulinemia, lymphoproliferative disorders, and kidney disease. HCV infection is both a cause and a complication of chronic kidney disease, occurring largely in the context of mixed cryoglobulinemia. This infection also represents a major medical and epidemiologic challenge in patients with end-stage renal disease on renal replacement therapy with dialysis or transplantation. In these settings the presence of HCV correlates with higher rates of patient mortality than in HCV-negative subjects on dialysis or undergoing kidney transplant. The major concern is the lack of safe and effective drugs to treat HCV-infected patients with chronic kidney disease. Unfortunately, there are no large-scale clinical trials in this population, especially those receiving renal replacement therapy, so that strong evidence for treatment recommendations is scant. This review article provides the readers with the most recent insights on HCV infection both as cause and complication of chronic kidney disease, discusses pitfalls and limitations of current therapies, and reports on preliminary experience with novel therapeutic agents, as well as directions for future research.

Interferon alpha delivery systems for the treatment of hepatitis C

Hepatitis C virus (HCV) infections are the most common chronic blood-borne viral infections in the world. The prevalence of HCV infections varies significantly by race or ethnicity, with a high prevalence of the disease displayed in the Hispanic population. Additionally, Hispanics with chronic HCV have also more advanced hepatic fibrosis and faster liver fibrosis progression rates than either African Americans or Caucasians. Furthermore, a higher prevalence of cirrhosis and extent of mortality from liver cirrhosis is also observed in the Hispanic population compared with other groups. Current recommendations for treatment of hepatitis C are interferon alpha (IFNalpha)-based monotherapy and combination of IFNalpha preparations with ribavirin. Future treatment regimens will still be based on IFNalpha therapy with or without other effective antiviral agents, currently under investigation. However, there are some inherent limitations, mainly their relative short systemic circulation lifespan, and their unwanted effects on some non-target tissues. New research focuses on the development of novel modified interferon molecules which demonstrate reduced side effects and extended systemic circulation time, which can ultimately provide greater efficacy. Alternative routes for IFNalpha delivery, such as oral delivery, demonstrate challenging but promising areas of research for improving future patient compliance.

Deterioration of health-related quality of life and fatigue in patients with chronic hepatitis C: Association with demographic factors, inflammatory activity, and degree of fibrosis

BACKGROUND/AIMS

Health-related quality of life (HRQoL) is impaired in patients with chronic hepatitis C. We investigated HRQoL and fatigue in patients with chronic hepatitis C virus (HCV) infection in relation to the degree of fibrosis and inflammation, and controlled for the influence of relevant demographic and medical variables.

METHODS

We conducted a cross-sectional two-center study including 215 outpatients with chronic hepatitis C applying the Short-Form Health Survey (SF-36) and the Fatigue Impact Scale (FIS-D). The contribution to the variability of these psychometric scores was evaluated for the degree of fibrosis as well as viremia, gender, age, mode of transmission, genotype, and ALT.

RESULTS

There was a strong negative association between the degree of liver fibrosis and the physical SF-36 summary score (p=0.016). This was independent of the covariate age, also significantly predicting physical HRQoL (p=0.001). The absolute FIS score was significantly increased in patients with advanced fibrosis (p=0.043). In females, mental SF-36 summary score (p=0.007) and fatigue (p=0.017) were significantly more impaired.

CONCLUSIONS

Our study suggests a significant association of physical aspects of HRQoL and fatigue with the extent of fibrosis. Fibrosis stage should be considered for the identification and management of HCV patients at risk for reduced physical HRQoL.

Placebo-controlled trial of 400 mg amantadine combined with peginterferon alfa-2a and ribavirin for 48 weeks in chronic hepatitis C virus-1 infection

The impact of amantadine on virologic response rates of interferon-based treatment of chronic hepatitis C is controversial. The aim of this study was to compare virological response rates in patients with chronic hepatitis C virus (HCV)-1 infection treated with 400 mg amantadine or placebo in combination with peginterferon alfa-2a (40 kD) and ribavirin for 48 weeks. Seven hundred four previously untreated chronically HCV-1-infected patients (mean age, 46 +/- 12 years) were randomized to (A) amantadine-sulphate (400 mg/day) (n = 352) or (B) placebo (n = 352), both in combination with 180 microg peginterferon alfa-2a once weekly and ribavirin (1000-1200 mg/day) for 48 weeks. End of treatment and sustained virological response after a 24-week follow-up period were assessed by qualitative reverse transcription polymerase chain reaction (RT-PCR) (sensitivity, 50 IU/mL). Demographic and baseline virological parameters were similar in both treatment groups. In groups A and B, 231 of 352 patients (66%) and 256 of 352 patients (72%) achieved an end of treatment response, and 171 of 352 patients (49 %) and 186 of 352 patients (53 %) a sustained virological response, respectively. On-treatment dropout rate in the amantadine group was significantly higher than in the placebo group (32% versus 23%; P = 0.01). However, adverse events and laboratory abnormalities were similar between both groups. Per-protocol analysis revealed similar sustained virological response rates in both treatment groups (53% versus 55%).

CONCLUSION

In this large placebo-controlled multicenter study, amantadine even at a dose of 400 mg/day did not improve virological response rates of peginterferon alfa-2a and ribavirin in patients with chronic genotype HCV-1 infection.

Peginterferon alpha-2a and ribavirin versus peginterferon alpha-2a monotherapy in early virological responders and peginterferon alpha-2a and ribavirin versus peginterferon alpha-2a, ribavirin and amantadine triple therapy in early virological nonresponders: the SMIEC II trial in naïve patients with chronic hepatitis C

OBJECTIVE

The objective of this study was to compare the efficacy of anti-hepatitis C virus (anti-HCV) treatment schedules on the basis of an early virological response (EVR), defined as undetectable serum HCV-RNA (<50 IU/ml) after a 12-week induction course of peginterferon alpha-2a (PEG-IFN) 180 mcg/week.

METHODS

A total of 210 interferon-naïve patients (69% male; median age, 42 years) with histologically proven chronic hepatitis C infection (genotype 1: 62%) received PEG-IFN 180 mcg/week for 12 weeks. Patients with EVR (58%) were randomized to continue PEG-IFN monotherapy (n=64) or to add ribavirin (RBV), 800 mg/day (n=57), for 36 additional weeks. Patients without EVR (42%) were randomized to add RBV (n=42), or RBV plus amantadine, 200 mg/day (n=47), for 36 additional weeks. Sustained virological response (SVR, undetectable HCV-RNA 24 weeks after treatment completion) was compared among treatment groups.

RESULTS

Patients with EVR: SVR rate was 60.3% in the PEG-IFN group versus 67.2% in the PEG-IFN+RBV group (NS). In genotypes 2/3, SVR rates were 66.7 versus 73.1% (NS); in genotypes 1/4, SVR rates were 51.6 versus 61.3%, respectively (NS). Patients without EVR: SVR was 16.7% in the PEG-IFN+RBV group versus 31.9% in the triple therapy group (P=0.07). In patients with genotypes 1/4, SVR rates were 9.4 versus 29.7% (P=0.041).

CONCLUSION

In genotypes 1/4 patients without EVR, triple therapy results in higher SVR rates than standard dual therapy. This study confirms that addition of amantadine is beneficial in early-recognized 'difficult-to-treat' patients.

Interferon treatment in hemodialysis patients with chronic hepatitis C virus infection: a systematic review of the literature and meta-analysis of treatment efficacy and harms

BACKGROUND

Hepatitis C virus (HCV) infection is prevalent in patients undergoing hemodialysis and is associated with greater mortality. We determined the efficacy and harms of interferon (IFN) and pegylated IFN (PEG-IFN) treatment of hemodialysis patients with chronic HCV infection and identified factors associated with these outcomes.

STUDY DESIGN

Meta-analysis and meta-regression of randomized controlled trials, uncontrolled trials, and prospective observational studies.

SETTING & POPULATION

Hemodialysis patients with chronic HCV infection.

SELECTION CRITERIA FOR STUDIES

MEDLINE indexed studies since 1966, sample size greater than 10.

INTERVENTION

IFN-based treatment, including PEG-IFN with and without ribavirin.

OUTCOMES

Sustained virological response (SVR) 6 months after treatment, rate of treatment discontinuation caused by adverse events, and factors associated with these outcomes.

RESULTS

20 studies of 459 IFN-treated patients, 3 studies of 38 PEG-IFN-treated patients, and 2 studies of 49 PEG-IFN and ribavirin-treated patients met inclusion criteria. The overall SVR rate was 41% (95% confidence interval [CI], 33 to 49) for IFN and 37% (95% CI, 9 to 77) for PEG-IFN. Treatment discontinuation rates were 26% (95% CI, 20 to 34) for IFN and 28% (95% CI, 12 to 53) for PEG-IFN. SVR was higher with 3 million units (MU) or higher of IFN 3 times weekly, with lower mean HCV RNA, and with lower rates of cirrhosis, HCV genotype 1 or elevated transaminase, but these findings were not statistically significant. Treatment discontinuation rates were greater in studies using larger doses.

LIMITATIONS

Publication bias, few randomized controlled trials, and limitations in generalizability to all hemodialysis patients.

CONCLUSION

IFN treatment of hemodialysis patients results in an SVR rate of 41%. Higher dose, lower mean HCV RNA level, and lower rates of cirrhosis, transaminase level increase, and HCV genotype 1 may be associated with greater SVR rates, but additional studies using individual patient data are needed.

Efficacy of amantadine on quality of life in patients with chronic hepatitis C treated with interferon-alpha and ribavirin: results from a randomized, placebo-controlled, double-blind trial

AIM

The aim of this study was to investigate whether amantadine reduces deterioration of quality of life in patients with chronic hepatitis C during and after treatment with interferon-alpha (IFN-alpha) and ribavirin.

PATIENTS AND METHODS

In this randomized, prospective, placebo-controlled, multicenter trial, previously untreated patients with chronic hepatitis C were treated with IFN-alpha plus ribavirin [17] and randomized for treatment with amantadine (200 mg/day, orally, n=136) or placebo (n=131). Quality of life was assessed with the 'Profile of Mood States' scale and the 'Everyday Life' questionnaire at baseline, treatment week (TW) 8, TW24, TW48, and at follow-up.

RESULTS

Early during treatment at TW8, quality of life was not different between patients in the control and the amantadine group. At TW24, the control group but not the amantadine group, however, showed significant deterioration of the modalities depression, fatigue, and vigor compared with baseline. Especially, nonresponders in the amantadine group showed significantly lower deterioration of depression, anger, mind function, everyday life, and zest for life than those in the placebo group. After treatment, the beneficial effects of amantadine disappeared.

CONCLUSION

The addition of amantadine to IFN-alpha plus ribavirin combination therapy may reduce deterioration of depression, fatigue, and vigor during treatment but does not affect quality of life after treatment.

Viral determinants of resistance to treatment in patients with hepatitis C

Chronic hepatitis C virus (HCV) infection affects more than 170 million persons worldwide and is responsible for the development of liver cirrhosis in many cases. Standard treatment with pegylated alpha interferon (IFN-alpha) in combination with the nucleoside analogue ribavirin leads to a sustained virologic response in approximately half of the patients. IFN-alpha is classified as an indirect treatment, as it interacts with the host's immune response. The mechanism of action of ribavirin is still unknown. The benefit of triple therapy by adding other antiviral agents, e.g., amantadine, is controversial. Currently, new direct antiviral drugs (HCV protease/polymerase inhibitors) are being evaluated in phase 1/phase 2 trials. Phenotypic resistance to antiviral therapy has been attributed to amino acid variations within distinct regions of the HCV polyprotein. While sensitivity to IFN-alpha-based antiviral therapy in vivo is clearly correlated with the number of mutations within the HCV NS5A protein, the underlying functional mechanisms for this association are unknown. In turn, in vitro, several mechanisms to circumvent the host immune defense or to block treatment-induced antiviral activities have been described for different HCV proteins. By the introduction of direct antiviral drugs, hepatitis C therapy now is entering a new era in which the development of resistance may become the most important parameter for treatment success or failure.

Hepatitis C Virus p7 membrane protein quasispecies variability in chronically infected patients treated with interferon and ribavirin, with or without amantadine

A clinical study was carried out to compare the response rate of two groups of non-responder (NR) hepatitis C virus (HCV) genotype 1 chronically infected patients treated with interferon and ribavirin, with or without amantadine. The viral load decreased more markedly in the group treated by tritherapy including amantadine, but the response rate at the end of treatment was not significantly different between bitherapy and tritherapy. As amantadine could have an antiviral effect on the ion channel activity of the p7 HCV protein, the p7 quasispecies was characterized by cloning and sequencing. Sequence data were analyzed to determine the pattern and significance of p7 genetic heterogeneity and a possible relationship with therapy. Subtype differences were confirmed between p7 HCV genotypes 1a and 1b, and quasispecies analysis showed a reduction of genetic diversity in subtype 1a, but not 1b, during tritherapy. However, the absence of changes at numerous positions, as well as the conservative changes at other positions, indicated the high conservation of the p7 structure. Residue His-17, proposed to interact with amantadine, was fully conserved in both subtypes 1a and 1b, independently of amantadine administration. In conclusion, although the analysis of the p7 sequences revealed a selective pressure during therapy, no specific residues appeared to be linked to the effect of amantadine on viral decline. These results suggest that the potential antiviral effect of amantadine might be non-specific and related to a reduction in endosomal acidification and therefore reduced viral entry of HCV via its pH-dependent pathway.

Amino Acid Variations in Hepatitis C Virus P7 and Sensitivity to Antiviral Combination Therapy with Amantadine in Chronic Hepatitis C

Background

Formation of transmembrane ion channels by hepatitis C virus (HCV) p7 and abrogation of channel function by amantadine was demonstrated in vitro. The relevance of HCV p7 amino acid (aa) variations for response to antiviral therapy with amantadine is unknown.

Methods

HCV p7 was sequenced in 86 individuals who were infected with HCV genotype 1. Thirty-six of 86 patients received amantadine within an interferon-α (IFN-α)-based antiviral therapy. Helical wheel modelling for HCV p7 was performed.

Results

No significant correlation of overall aa variations within HCV p7 was observed with response to IFN-α-based therapy with amantadine in HCV genotype 1a/b infected patients. When analysis was restricted to non-conservative aa variations, a higher number of aa substitutions within complete HCV p7 and transmem-brane helix 2 was associated with non-response in HCV-1b-infected patients receiving therapy with amantadine ( P=0.015 and P=0.037, respectively), without amantadine ( P=0.106 and P=0.118, respectively), and in the total cohort of HCV-1b-infected patients ( P=0.00007 and P=0.011, respectively). Furthermore, substitution L20F was observed more often in non-responders than responders with HCV-1b infection and therapy with amantadine ( P=0.099). By in silico modelling, aa 20 was located toward the p7 channel lumen. Substitution L20F may impair amantadine action by altering the shape of the ion channel pore.

Conclusion

Substitution L20F within HCV p7 may be associated with non-response to combination therapy specifically with amantadine in HCV-1b-infected patients. Non-responders with HCV-1b infection showed higher numbers of non-conservative aa variations within HCV p7 than responders, irrespective of the application of amantadine.

Randomized, double-blind, placebo-controlled study of peginterferon alfa-2a (40KD) plus ribavirin with or without amantadine in treatment-naïve patients with chronic hepatitis C genotype 1 infection

BACKGROUND/AIMS

Amantadine may augment virological response rates to interferon-based therapy in chronic hepatitis C patients. Using a novel design, amantadine was studied in naïve genotype 1 patients treated in combination with peginterferon alfa-2a (40KD)/ribavirin.

METHODS

Patients enrolled in this randomized, placebo-controlled multicenter trial were stratified by single-dose interferon sensitivity (stratum I, 24-h HCV-RNA decline >1.4-log10; II, 0.8-1.39-log10; III, <0.8-log10; a reliable means of identifying nonresponders to interferon/ribavirin) and fibrosis grade (F0/1/2 vs. F3/4) at baseline. All patients received peginterferon alfa-2a (40KD) 180 microg/week plus ribavirin 1000-1200 mg/day and were randomized to receive amantadine 100 mg twice daily (N = 114) or placebo (N = 95) for 48 weeks.

RESULTS

Week-24 virological response rates in strata II and III, the primary outcome, were similar in patients treated with amantadine (63.7%) or placebo (65.7%), as were sustained virological response rates at week 72 (46.5 and 51.6%, respectively). Adverse event profiles were similar and amantadine did not improve health-related quality of life compared with placebo. Interferon sensitivity was the only significant predictor of treatment outcome.

CONCLUSIONS

Adding amantadine to peginterferon alfa-2a (40KD)/ribavirin combination therapy does not augment virological response rates in genotype 1 patients. Virological response was almost exclusively determined by interferon sensitivity at baseline.

Amantadine in treatment of chronic hepatitis C virus infection?

SUMMARY

Treatment of chronic hepatitis C (CHC) continues to be an important and growing challenge. As the response rate to FDA-approved treatment improved over the past decade, we are facing increasing number of difficult-to-treat patients such as those who have failed prior anti-viral therapy. The role of amantadine in the treatment of CHC remains unclear. Studies thus far have produced conflicting results, and type II error could not be excluded. This review summarized results published in the literature from 1997 to 2003, and reviewed the existing questions and controversies regarding the use of amantadine. Current literature suggests that amantadine is ineffective as monotherapy. Amantadine increased the sustained virologic response of certain treatment naïve patients when used in combination with interferon, and may be effective as an adjunct to interferon-based combination therapy in some patients who have failed or relapsed on prior therapy. Factors such as small sample size, patient characteristics, and differences in treatment protocols including amantadine preparation and duration of therapy might explain the conflicting observations of various studies. Further investigations are needed to define optimal dosing and formulation of amantadine, and its appropriate role in management of CHC infection.

A decade of trials of interferon-alpha for chronic hepatitis C. A meta-regression analysis

The most relevant randomized controlled trials of interferon-alpha (IFN) for naive patients with chronic hepatitis C (CHC) published in a decade, just before appearance of pegylated IFN trials in 2000, were included in this paper. Its purpose is to review the relationship between sustained biochemical response in active versus control group versus usual clinical variables as IFN regimens, cirrhosis, genotype and versus less frequently addressed variables as funding, methodological quality or location of principal author. Meta-analysis estimates of global treatment effect varied according to trial design: group 1=IFN versus placebo/no treatment, 32 RCTs, 2499 pts, OR 9.5 (6.3-14.2); group 2a=comparison of IFN schedules, 43 RCTs, 7454 pts, OR 1.6 (1.4-1.9); group 2b=IFN+other drugs versus standard IFN, 30 RCTs, 4737 pts, OR 2.0 (1.6-2.6). Fixed effects (arm-level) meta-regression on the complete data set (171 arms, 10,580 pts) revealed that sustained response was most likely in experimental arms of IFN+ribavirin or other drugs (OR 2.4), arms using yearly schedule (OR 2.0), trial principal author from Asia (OR 1.7), trial sample size >200 (OR 1.4) and arms enrolling less than 50% of cirrhotics (OR 1.3). Moreover, focus was on some significant interactions too, as the effect of trial's quality interacting to the recorded funding (more benefit if no-profit, less if for-profit) and the effect of trial funding interacting to the location of first author (more benefit if from Asia). Three main effects (experimental arm, cirrhosis, funding) and one interaction (funding*location of principal author) explained 31% of between study variability in a random-effect meta-regression. In a subgroup analysis on a data set including available information on HCV genotype (93 arms, around 7000 pts), meta-regression revealed that genotype 1 or 4 less than 50% per arm and specialistic journal were significant predictors of either biochemical (transaminases) or virological (HCV-RNA) sustained response, in a model including the same main effects identified in the complete data set analysis. Finally, although mostly captured by different IFN regimens along time, heterogeneity of effect in a large set of (not-pegylated) IFN trials was also explained by HCV genotype and variables of quality and reporting, such as trial's principal author from Asia.

A randomized controlled trial of pegylated interferon alpha-2a (40 KD) or interferon alpha-2a plus ribavirin and amantadine vs interferon alpha-2a and ribavirin in treatment-naïve patients with chronic hepatitis C

We determined whether triple therapy comprising amantadine (AMA), ribavirin (RBV) and either peginterferon (PEG-IFN) alpha-2a or conventional IFN alpha-2a would improve sustained virological response (SVR) rates over dual therapy with IFN alpha-2a and RBV in patients with chronic HCV infection. A total of 362 treatment-naïve patients were randomized to 48 weeks of treatment with: PEG-IFN alpha-2a 180 microg/week (group A) or IFN alpha-2a 3 MU tiw (groups B and C). All patients received RBV 1000 or 1200 mg/day and those in groups A and B received AMA 200 mg/day. SVR was defined as an undetectable HCV RNA after 24 weeks of untreated follow-up. At the end of therapy, 74.4% (95% CI 0.66-0.82) of patients in group A were HCV RNA-negative compared with 42.5% (95% CI 0.33-0.50) of those in group B (P = 0.0001) and 48.8% (95% CI 0.40-0.56) of those in group C. SVR was achieved in a significantly greater proportion of patients in group A compared with groups B and C: 65.3% (95% CI 0.53-0.56), 33.3% (95% CI 0.25-0.41) and 44.6% (95% CI 0.36-0.53; P = 0.0001) respectively. In patients with genotype 1, SVR rates were 55.2, 22.8 and 28.8% with the three regimens respectively. Factors independently associated with SVR were HCV genotype 2 or 3, therapy with PEG-IFN, female gender and age. In treatment-naive patients with chronic hepatitis C, triple therapy with PEG-IFN alpha-2a, RBV and AMA produces higher SVR than dual or triple therapy with conventional IFN alpha-2a.

Therapeutic modalities in hepatitis C: challenges and development

Our understanding of the pathogenicity of hepatitis C virus (HCV) is based on patients infected chronically for >20 years. The lack of a suitable animal model, the narrow host range of the virus, and the protracted onset of liver disease induced by HCV have hampered advances in treatment. In spite of these problems, we identified patient and viral characteristics that predict responses to current therapies, including HCV genotype, viral load, body weight, age, liver histology, co-infection with HIV and treatment adherence and tolerance. Interferon (IFN) alpha was the first therapy for chronic HCV infection. The combination of IFN plus ribavirin increases sustained virological response rates compared with IFN alone. Two pegylated IFNs have been developed and are widely approved for the treatment of chronic hepatitis C: peginterferon alpha-2a (40 KD), and pegylated IFN alpha-2b (12 KD). These products have reduced systemic clearance, prolonged half-lives and reduced antigenicity compared with conventional IFN. The reduced clearance results in sustained plasma levels of the drug and allows for once-weekly dosing. Pegylated IFN alpha-2b (12 KD) has a small, linear polyethylene glycol (PEG) moiety and has an intermediate duration of activity; peginterferon alpha-2a (40 KD) incorporates a large, branched-chain PEG moiety and has a longer half-life than both conventional IFN alpha and pegylated IFN alpha-2b (12 KD). The combination of a pegylated IFN plus ribavirin significantly increases sustained virological response rates compared with conventional IFN plus ribavirin in patients with chronic hepatitis C and is now recognized as the standard of care for these patients.

Retreatment of patients with chronic hepatitis C not responding to interferon/ribavirin combination therapy with daily interferon plus ribavirin plus amantadine

There is currently no accepted therapeutic regimen for patients with chronic hepatitis C who failed to respond to standard combination treatment with interferon-alpha plus ribavirin. We investigated triple combination treatment with induction dosing of interferon-alpha plus ribavirin plus amantadine in these difficult-to-treat patients. Nonresponders (n = 67), breakthroughs (n = 16) and relapsers (n = 19) to previous interferon/ribavirin combination treatment of at least 6 months were included. For the first 16 weeks, patients received interferon-alpha2a 6 MU daily, ribavirin 800-1200 mg/d, and amantadine 200 mg/d. In cases of undetectable HCV RNA at week 12, treatment was continued with interferon-alpha2a 6 MU every other day and the same doses of ribavirin and amantadine until week 48. In cases of HCV RNA positivity at week 12, treatment was stopped. A total of 102 patients were enrolled (80%: genotype 1, 19%: cirrhosis). HCV RNA was negative in 35/102 patients (34%) at week 12 and in 27/ 102 patients (26%) at the end of treatment. Virological response was sustained in 15/102 patients (15%). On-treatment virological response was higher in previous relapsers/breakthroughs than in previous nonresponders (week 12: 49% vs. 27%, p < 0.05; week 48: 46% vs. 16%, p < 0.01) but no such difference was found for sustained virological response (20% vs. 12%, NS). In conclusion, triple combination treatment with daily interferon-alpha plus ribavirin plus amantadine for 3 months can induce virological response in a considerable number of nonresponders/relapsers to previous dual combination treatment, but the sustained virological response rate remains low.

Evaluation of amantadine in chronic hepatitis C: a meta-analysis

BACKGROUND/AIMS

The benefit of amantadine combination therapy, either with interferon (IFN) alone (double therapy) or with ribavirin and IFN (triple therapy) is unknown.

METHODS

We analyzed the effect of amantadine on the end-of-treatment virological response and the sustained response using meta-analysis of 31 randomized controlled trials.

RESULTS

Overall analysis revealed a significant effect of amantadine. Triple therapy was the best regimen for improving the sustained response (mean difference: 8.4%, 95% CI: 2.4-13.8%, P=0.002). In subgroup analysis, amantadine did not have a significant effect upon naive patients or relapsers. In non-responders, combination therapy with amantadine was associated with a significant effect on the sustained response (mean difference: 8.3%, 95% CI: 1.9-14.6%, P=0.01). In sensitivity analysis, double therapy did not improve virological responses. Conversely, triple therapy tended to improve the end-of-treatment virological response and was associated with a significant effect upon the sustained response (mean difference: 12.7%, 95% CI: 3.8-21.6%, P=0.005).

CONCLUSIONS

Combination therapy with amantadine is of no effect upon naive patients or relapsers. In non-responders, triple therapy with amantadine improved the sustained response. New randomized controlled trials are required to confirm this meta-analysis.

Amantadine therapy for chronic hepatitis C

OBJECTIVE

Although treatment of hepatitis C has improved, up to 50% do not respond to standard therapy with interferon regimes or cannot tolerate the treatment due to side effects. The purpose of the present investigation was to evaluate the safety and effectiveness of the antiviral drug amantadine for the treatment of hepatitis C in those who had either previously failed interferon therapy or were not candidates for interferon.

DESIGN

A prospective double-blind randomized placebo-controlled trial.

SETTING

Outpatient research clinic of a teaching hospital.

PATIENTS/PARTICIPANTS

One hundred fifty-two patients with confirmed hepatitis C with abnormal liver enzymes, detectable hepatitis C RNA in the blood, and abnormal liver histology by biopsy were randomized to receive treatment or placebo.

MEASUREMENTS AND MAIN RESULTS

Patients received either amantadine 100 mg twice daily by mouth or placebo for 6 months. After 6 months, placebo-treated patients were crossed over and treated with amantadine for 6 months and amantadine-treated subjects received 6 additional months of therapy. Amantadine therapy resulted in a significant decline in serum alanine aminotransferase compared to placebo (P =.03). Nine percent cleared the virus at the end of therapy and 6.8% had a sustained virologic response 6 months after discontinuation of amantadine, but this was not statistically significant. Side effects were minimal, and the social quality of life survey improved with 12 months of amantadine (P =.02).

CONCLUSIONS

Oral amantadine may provide a safe alternative treatment for those patients who are intolerant or unresponsive to interferon.

Validation of the German version of the Chronic Liver Disease Questionnaire

OBJECTIVE

The Chronic Liver Disease Questionnaire is an instrument for the assessment of health-related quality of life in patients with chronic liver diseases. So far it has not been validated for German speaking countries.

METHODS

Two hundred and three consecutive patients with chronic liver diseases (age, 52.7 +/- 13.9 years; 47% female; 45% no cirrhosis, 21% Child's class A, 15% Child's class B and 17% Child's class C cirrhosis; 52% with chronic viral hepatitis, 32% with alcoholic and 16% with other liver diseases) of a liver centre completed the German version of the Chronic Liver Disease Questionnaire (CLDQ-D), the Short Form Health Survey SF-36, the Hospital Anxiety and Depression Scale (HADS) and the Giessener Symptom List GBB-24. Fifty stable patients filled in the CLDQ-D a second time within 3 - 8 days.

RESULTS

With 97.7% completed items the acceptance by the patients was high. The internal consistency (Cronbach alpha) for the subscales ranged from 0.69 to 0.95, the test-retest reliability ranged from 0.79 to 0.88. The correlation coefficients with similar subscales of the instruments used for validation ranged between 0.5 and 0.9 (convergent validity). Patients with liver cirrhosis Child-Pugh stage C scored significantly lower in the subscales 'Abdominal Symptoms', 'Activity' and 'Worry', indicating a reduced health-related quality of life than in patients without cirrhosis (P < 0.05) (discriminant validity).

CONCLUSION

The CLDQ-D is well accepted by patients with chronic liver diseases and has good reliability and satisfactory discriminant validity.

Combination therapy with amantadine and interferon in naïve patients with chronic hepatitis C: meta-analysis of individual patient data from six clinical trials

BACKGROUND/AIMS

In chronic hepatitis C, clinical trials evaluating the efficacy of amantadine (AMA) and interferon (INF) compared to INF monotherapy, have produced conflicting results. We performed a meta-analysis of the individual patient's data from previous studies.

METHODS

Nine hundred and seventy-two patients from six European centres were evaluated by means of individual patient meta-analysis, using mixed models with centres and the centre-treatment interaction fitted as random variables.

RESULTS

At the end of therapy, virological responses were 38.5% (95% CI 34.1-42.8) after INF and AMA, and 29.5% (95% CI 25.5-33.6) after INF alone (P = 0.003). Sustained response occurred in 111 (23.1%; 95% CI 19.3-20.2) and 85 patients (17.3%; 95% CI 14.0-20.7), respectively (P = 0.03). Even accounting for the centre effect, therapy with AMA and INF was more effective than IFN alone (P = 0.029). When genotypes and viraemia levels were combined, the response rate after combination therapy doubled that observed with IFN alone in all subgroups, except those with low viraemia and genotypes 2 or 3.

CONCLUSIONS

In chronic hepatitis C, therapy with AMA and INF is effective and may be an alternative to INF and ribavirin in patients who cannot tolerate ribavirin.

A randomized controlled trial of amantadine plus interferon-alpha2a vs. interferon-alpha2a alone in naive patients with chronic hepatitis C randomized according to the early virological response to interferon-alpha2a monotherapy

BACKGROUND

An early virological response to interferon-alpha treatment is a strong predictor of sustained response, but it has never been exploited to stratify patients in clinical trials.

AIM

To evaluate the efficacy of amantadine plus interferon-alpha compared with interferon-alpha alone in naive patients with chronic hepatitis C who were randomized on the basis of the early virological response to interferon-alpha.

METHODS

One hundred and eighty-one patients received recombinant interferon-alpha2a (3 MU three times weekly) for 2 months and 164 were evaluated for early (i.e. month 2) virological response. Hepatitis C virus (HCV) RNA-negative patients (n = 66) were randomized to receive 3 MU of interferon-alpha three times weekly, with or without amantadine (200 mg/day); HCV RNA-positive patients (n = 98) were randomized to receive 6 MU of interferon-alpha three times weekly, with or without amantadine (200 mg/day). HCV RNA-positive patients at 6 months discontinued treatment, and all others completed 12 months.

RESULTS

At month 6, HCV RNA-negative patients made up 54.2% of the interferon + amantadine group and 42.0% of the monotherapy group (P = 0.07). At month 12, HCV RNA-negative patients made up 38.5% of the interferon + amantadine group and 28.4% of the monotherapy group (N.S.). The sustained virological response rates were 21.6% and 20.9%, respectively (N.S.).

CONCLUSION

The addition of amantadine does not enhance the sustained virological response to interferon-alpha in naive patients with chronic hepatitis C; however, an additive effect of amantadine occurs in the first 6 months, mainly in patients without an early response to monotherapy. Early response to interferon-alpha is a strong predictor of sustained virological response.

Randomised, double blind, placebo controlled trial of interferon, ribavirin, and amantadine versus interferon, ribavirin, and placebo in treatment naïve patients with chronic hepatitis C

BACKGROUND AND AIM

In this study, we compared the efficacy of triple therapy (interferon alfa, ribavirin, and amantadine) with standard therapy (interferon alfa and ribavirin) in treatment naïve patients with chronic hepatitis C virus (HCV).

METHODS

In this prospective, randomised, double blind, placebo controlled, multicentre study, 85 patients (amantadine group) received a three drug regimen of interferon alfa-2b 3 million units three times per week, ribavirin 1000-1200 mg daily in divided doses, and amantadine 100 mg twice daily, and 86 patients (placebo group) received interferon alfa-2b, ribavirin, and identical placebo. Treatment was discontinued at 24 weeks if patients had detectable HCV RNA by polymerase chain reaction (PCR). All patients were followed for 24 weeks after completion of treatment. The primary end point was undetectable HCV-RNA by PCR at 24 weeks (sustained viral clearance) after completion of treatment.

RESULTS

At the end of treatment, HCV RNA clearance was seen in 32.9% of the amantadine group and 38.4% of the placebo group (p=0.3). Sustained virological response was seen in 24.7% of the amantadine group and in 27.9% of the placebo group by intention to treat analysis; response rate was 30.4% and 34.8%, respectively, in those who completed 24 weeks of treatment. Poor response was seen in both groups among cirrhotics, African-Americans, genotype 1, and those with a higher viral load. By multivariate analysis, genotype 1, high viral load, and low serum albumin were the only predictors of poor response. Addition of amantadine to the standard regimen did not result in any unexpected side effects.

CONCLUSION

Response to triple therapy of interferon alfa, ribavirin, and amantadine was similar to standard therapy of interferon alfa and ribavirin. Our results suggest that amantadine has no role in the management of HCV.

Interferon alfa2a induction therapy in combination with ribavirin and amantadine for the treatment of naive patients with chronic HCV infection

Pilot studies have suggested that the addition of amantadine to interferon (IFN) is effective against hepatitis C virus (HCV). Furthermore, IFN induction therapy seems to improve virological response rates. In this open, randomized, multicentre trial we compared safety and efficacy of a triple therapy comprising IFN alpha 2a, ribavirin and amantadine using high induction doses (6 MU IFN alpha daily for the first 6 weeks) against a therapy with standard IFN alpha dosages over the entire treatment period plus amantadine and ribavirin. A total of 158 naive patients with chronic HCV infection were randomized 1:1. Group A (n = 81): induction therapy with 6 MU IFN alpha daily for 6 weeks, followed by 6 MU three times a week (tiw) for 18 weeks and then 3 MU tiw until week 48. Group B (n = 77): standard therapy with 6 MU IFN alpha tiw for 24 weeks, followed by 3 MU until week 48. All patients received oral ribavirin (10 mg/kg/day) and amantadine (200 mg/day). The triple therapy was safe and well tolerated. There were no significant differences between the groups with respect to biochemical response rates. Groups A and B did not differ in virological response rates at the end of treatment (33%vs 35%) or at the end of the 6 month follow up period (37%vs 39%). We could not detect favourable effects on sustained virological response rates using induction therapy, in either genotype 1 or non-1 infected patients. In summary, induction therapy with 6 MU IFN alpha daily did not result in increased overall response rates compared with standard IFN alpha dosages of 6 MU tiw.

Triple therapy with amantadine in treatment-naive patients with chronic hepatitis C: a placebo-controlled trial

The antiviral efficacy of amantadine in patients with chronic hepatitis C is controversial. In this randomized, prospective, placebo-controlled, multicenter trial, triple therapy with interferon alfa (IFN-alpha)-2a plus ribavirin and amantadine (amantadine group) was compared with combination therapy IFN-alpha plus ribavirin (control group). Four hundred previously untreated patients with histologically proven chronic hepatitis C were randomly allocated to treatment with amantadine sulphate (100 mg twice daily orally) or a matched placebo together with IFN-alpha induction plus ribavirin (1,000-1,200 mg/day orally) for 48 weeks. The primary end point was sustained virologic response (SVR) defined as undetectable serum hepatitis C virus (HCV) RNA (<100 copies/mL) 24 weeks after the end of treatment. SVR was observed in 52% of the amantadine group and in 43.5% of the control group (P =.11). Among patients with HCV genotype 1 infection, the corresponding SVR rates were 39% and 31%, respectively. The virologic on-treatment response rate in week 24 was significantly higher in the amantadine group as compared with the control group (70% vs. 59%, respectively, P =.016). This beneficial effect was mainly related to HCV type 1-infected patients (63% vs. 47%, respectively, P =.012). Independent factors associated with SVR, according to multiple logistic regression analysis, were amantadine treatment, low baseline HCV RNA, platelet counts (>/=250/nL), pretreatment ALT quotient >/=3, and GGT level (<28 U/L) as well as HCV genotypes other than 1. In conclusion, although we could not demonstrate a significant advantage of the triple regimen in univariate analysis, multivariate analysis offers arguments that amantadine should be considered as a potential anti-HCV drug in future studies.

Effects of alpha interferon induction plus ribavirin with or without amantadine in the treatment of interferon non-responsive chronic hepatitis C: a randomised trial

BACKGROUND

Fifty per cent of chronic hepatitis C patients are non-responders to interferon. At present, there are no recommended therapeutic options for non-responders.

AIMS

The safety and long term effect of alpha interferon induction plus ribavirin with or without amantadine in the treatment of interferon non-responsive chronic hepatitis C was evaluated.

PATIENTS AND METHODS

A total of 114 consecutive patients were randomly divided into three groups with a final 2:2:1 ratio: group A (44 patients) received interferon alfa 2b, 3 million units (MU), three times a week, and oral ribavirin (1000 mg/day); group B (46 patients) received interferon 3 MU daily for the first four weeks and subsequently 3 MU three times a week, and ribavirin as in regimen A; and group C (24 patients) received interferon and ribavirin as in regimen B, plus oral amantadine hydrochloride (200 mg/day). The duration of treatment was 12 months.

RESULTS

The end of treatment response for groups A and B was 25% and 29%, respectively, and for group C, 68% (p<0.005). At the end of one year of follow up, a sustained response was observed for six (25%) patients in group C, one (2%) patient in group A, and two (4%) patients in group B (p<0.002). The triple regimen was well tolerated and did not increase the frequency or severity of side effects.

CONCLUSIONS

The study demonstrates that for the treatment of interferon non-responder hepatitis C patients, the association of interferon-ribavirin has a negligible long term effect whereas a triple regimen including interferon, ribavirin, and amantadine can be an effective and safe treatment.

Combination therapy with interferon-alpha(2b), ribavirin, and amantadine in chronic hepatitis C nonresponders to interferon and ribavirin

Standard therapies for the treatment of hepatitis C are ineffective in almost 50% of patients. Amantadine is an antiviral agent that may have activity against hepatitis C virus. In this pilot study, we evaluated the efficacy of a combination of interferon, ribavirin, and amantadine in patients with chronic hepatitis C who had previously failed 6-12 months of treatment with interferon and ribavirin. In this prospective open-label study, 23 patients were treated with a combination of interferon-alpha(2b) 3 million units subcutaneously three times per week, ribavirin 1000-1200 mg daily, and amantadine 100 mg twice daily for 6-12 months. Treatment was discontinued at 6 months if the patients had detectable HCV RNA by PCR. All patients were followed for 6 months after the completion of treatment. At the end of treatment, the biochemical response was 47% and the virological response was 30%. However, the rate of sustained virological response was only 13% (3/23). There were no unexpected side effects with triple therapy. In conclusion, triple therapy with interferon, ribavirin and amantadine resulted in a low sustained viral clearance in chronic hepatitis C patients who had previously failed interferon and ribavirin combination therapy.

Hepatitis C virus therapies: current treatments, targets and future perspectives

Chronic hepatitis C virus (HCV) infection is the cause of an emerging global epidemic of chronic liver disease. Current combination therapies are at best 80% efficacious and are often poorly tolerated. Strategies to improve the therapeutic response include the development of novel interferons, nucleoside analogues with reduced haemolysis compared with ribavirin and inosine 5'-monophosphate dehydrogenase inhibitors. Compounds in preclinical or early clinical trials include small molecules that inhibit virus-specific enzymes (such as the serine proteases, RNA polymerase and helicase) or interfere with translation (including anti-sense molecules, iRNA and ribozymes). Advances in understanding HCV replication, obtaining a sub-genomic replicon and contriving potential small animal models, in addition to solving crystallographic structures for the replication enzymes, have improved prospects for developing novel therapies. This review summarizes current and evolving treatments for chronic hepatitis C infection. In addition, progress in HCV targets and drug discovery tools valuable in the search for novel anti-HCV agents is detailed.

High-dose interferon alpha-2a with ribavirin and amantadine in naïve chronic hepatitis C patients--results of a randomized, prospective, pilot study

BACKGROUND

Hepatitis C viral kinetic studies have demonstrated the increased anti-viral effect of higher than standard dosages of interferon and of daily treatment schedules.

AIM

To compare, in a prospective, randomized, controlled trial, the efficacy and safety of high-dose interferon-alpha therapy vs. standard-dosage interferon-alpha therapy, in a triple therapy combination with ribavirin and amantadine.

METHODS

Previously untreated patients with chronic hepatitis C were randomized to the standard interferon-alpha group (n = 15), receiving thrice weekly 6 MU interferon-alpha for 12 weeks, followed by 3 MU interferon-alpha for 36 weeks, or the high-dose interferon-alpha group (n = 15), receiving daily 9 MU interferon-alpha for 4 weeks, followed by 6 MU (weeks 5-8), 3 MU (weeks 9-12) and 1.5 MU (weeks 13-48) interferon-alpha. All patients were given ribavirin (1000-1200 mg) and amantadine (200 mg) daily for 48 weeks.

RESULTS

At the end of treatment and after the 24-week follow-up period, serum hepatitis C virus RNA was undetectable in eight (53%) and six (40%) patients treated with standard-dosage interferon-alpha, respectively, compared with 11 (73%) and 10 (67%) treated with high-dose interferon-alpha, respectively (not significant). The safety profile of both treatment regimens was similar. Severe adverse events leading to withdrawal from the study occurred in one patient (7%) in each group, and in both groups one patient (7%) was lost during therapy for unknown reasons.

CONCLUSIONS

The findings suggest that, although the difference between the response rates of standard and high-dose interferon-alpha regimens (within a triple anti-viral therapy combination) did not reach statistical significance, there was a clear trend towards a higher response with high-dose interferon-alpha therapy and an equal safety profile.

Role of liver biopsy in management of chronic hepatitis C: a systematic review

This systematic review addresses 2 questions pertinent to the need for pretreatment liver biopsy in patients with chronic hepatitis C: how well do liver biopsy results predict treatment outcomes for chronic hepatitis C? How well do biochemical blood tests and serologic measures of fibrosis predict the biopsy findings in chronic hepatitis C? Medline and other electronic databases were searched from January 1985 to March 2002. Additional articles were sought in references of pertinent articles and recent journals and by querying experts. Articles were eligible for review if they reported original human data from a study that used virological, histological, pathologic, or clinical outcome measures. Paired reviewers assessed the quality of each eligible study and abstracted data. Studies suggested that advanced fibrosis or cirrhosis on initial liver biopsy is associated with a modestly decreased likelihood of a sustained virological response (SVR) to treatment. Also, studies relatively consistently showed that serum aminotransferases have modest value in predicting fibrosis on biopsy; that extracellular matrix tests hyaluronic acid and laminin may have value in predicting fibrosis, and that panels of tests may have the greatest value in predicting fibrosis or cirrhosis. Biochemical and serologic tests were best at predicting no or minimal fibrosis, or at predicting advanced fibrosis/cirrhosis, and were poor at predicting intermediate levels of fibrosis. Thus, evidence suggests that liver biopsy may have some usefulness in predicting efficacy of treatment in patients with chronic hepatitis C, and biochemical blood tests and serologic tests currently have only modest value in predicting fibrosis on liver biopsy.

Role of liver biopsy in management of chronic hepatitis C: a systematic review

This systematic review addresses 2 questions pertinent to the need for pretreatment liver biopsy in patients with chronic hepatitis C: how well do liver biopsy results predict treatment outcomes for chronic hepatitis C? How well do biochemical blood tests and serologic measures of fibrosis predict the biopsy findings in chronic hepatitis C? Medline and other electronic databases were searched from January 1985 to March 2002. Additional articles were sought in references of pertinent articles and recent journals and by querying experts. Articles were eligible for review if they reported original human data from a study that used virological, histological, pathologic, or clinical outcome measures. Paired reviewers assessed the quality of each eligible study and abstracted data. Studies suggested that advanced fibrosis or cirrhosis on initial liver biopsy is associated with a modestly decreased likelihood of a sustained virological response (SVR) to treatment. Also, studies relatively consistently showed that serum aminotransferases have modest value in predicting fibrosis on biopsy; that extracellular matrix tests hyaluronic acid and laminin may have value in predicting fibrosis, and that panels of tests may have the greatest value in predicting fibrosis or cirrhosis. Biochemical and serologic tests were best at predicting no or minimal fibrosis, or at predicting advanced fibrosis/cirrhosis, and were poor at predicting intermediate levels of fibrosis. Thus, evidence suggests that liver biopsy may have some usefulness in predicting efficacy of treatment in patients with chronic hepatitis C, and biochemical blood tests and serologic tests currently have only modest value in predicting fibrosis on liver biopsy.

Frontiers in Gastroenterology

There have been a number of exciting advancements and changes in the gastroenterology field over the last few years. A new mesalamine formulation, balsalazide disodium, is now available for the treatment of ulcerative colitis (UC). Balsalazide may be utilized as first line therapy for patients with UC, or patients who are intolerant to other mesalamine preparations. In the area of irritable bowel syndrome, alosetron was removed from the market after reports that it was associated with severe constipation and death, although a causal relationship could not be established. Published data examines the risk of certain medications and the development of reflux disease and esophageal adenocarcinoma.

Also, new proton pump inhibitors (PPIs) are available, esomeprazole, as well as alternate methods of administration for others. The first intravenous PPI, pantoprazole, is available in the United States, although currently there is a paucity of data regarding its efficacy. Peptic ulcer disease is also discussed, including Helicobacter pylori resistance, nonsteroidal anti-inflammatory drugs, and the treatment of bleeding ulcers. With pegylated interferon, progress in the treatment of hepatitis C offers promise for many patients. This review will highlight many recent changes in gastroenterology an offer a perspective on how disease management has changed.

The impact of liver disease on health-related quality of life: a review of the literature

Quality of life as an outcome variable has become an important measure in clinical research. Making a transition from a "biomedical model" of health to one that incorporates the social aspects of disease, clinicians and researchers dealing with chronic illness now incorporate quality-of-life measures into clinical practice and research. Chronic liver disease has shown a significant impact on the well-being of patients and contributes to the significant morbidity associated with these conditions. In this article, we review the recent research that has examined the impact of chronic liver disease on health-related quality of life.

Interferon and amantadine in naive chronic hepatitis C: a double-blind, randomized, placebo-controlled trial

Recent controlled trials on the efficacy of an amantadine/interferon combination in treatment-naive patients with chronic hepatitis C yielded contradictory results. We therefore conducted a large, double-blind, placebo-controlled, multicenter trial in naive patients with chronic hepatitis C: 246 patients were randomized to receive interferon alfa-2a (6 MIU sc thrice weekly for 20 weeks, then 3 MIU sc thrice weekly) and either amantadine sulphate (2 x 100 mg p.o. QD) or placebo. Treatment continued for a total of 52 weeks, if HCV-RNA in serum polymerase chain reaction (PCR) had fallen below detection limit (1,000 copies/mL) at treatment week 10, and stopped otherwise. All patients were followed for 24 weeks off therapy. After 10 weeks of treatment, 66/121 patients treated with amantadine (55%) and 78/125 treated with placebo (62%) had lost HCV-RNA (n.s.). After 24 weeks of follow-up, 25 patients in the amantadine (21%) and 17 (14%) in the placebo group remained HCV-RNA negative (n.s.). During therapy, virologic breakthroughs occurred less often in the amantadine than in the placebo group [14 (12%) vs. 27 (22%) patients; P =.04]. Multivariate logistic regression analysis revealed genotype, viremia level, age, and amantadine therapy [risk ratio 0.4 (95%CI 0.2-1.0), P =.05] as predictors of sustained virologic response. Adverse events and impact of therapy on quality of life were similar in amantadine and placebo treated patients. Compared with current standard treatment (interferon/ribavirin), the interferon/amantadine combination was not cost-effective. In conclusion, amantadine does not add to a clinically relevant extent to the treatment of naive patients with chronic hepatitis C.