Treatment with interferon-alpha2a alone or interferon-alpha2a plus ribavirin in patients with chronic hepatitis C previously treated with interferon-alpha2a. CONSTRUCT Group

A statistical method for removing unbalanced trials with multiple covariates in meta-analysis

In meta-analysis literature, there are several checklists describing the procedures necessary to evaluate studies from a qualitative point of view, whereas preliminary quantitative and statistical investigations on the "combinability" of trials have been neglected. Covariate balance is an important prerequisite to conduct meta-analysis. We propose a method to identify unbalanced trials with respect to a set of covariates, in presence of covariate imbalance, namely when the randomized controlled trials generate a meta-sample that cannot satisfy the requisite of randomization/combinability in meta-analysis. The method is able to identify the unbalanced trials, through four stages aimed at achieving combinability. The studies responsible for the imbalance are identified, and then they can be eliminated. The proposed procedure is simple and relies on the combined Anderson-Darling test applied to the Empirical Cumulative Distribution Functions of both experimental and control meta-arms. To illustrate the method in practice, two datasets from well-known meta-analyses in the literature are used.

Efficacy and tolerability of combination therapy with interferon-alfa plus ribavirin in patients with chronic hepatitis C virus infection: a single-center study in relapsers and nonresponders to previous treatment with high-dose interferon-alfa monotherapy

BACKGROUND

In chronic hepatitis C virus (HCV) infection, interferon (IFN) monotherapy usually is carried out at doses of 3 to 6 million units (MU) 3 times per week, but treatment efficacy is low.

OBJECTIVE

The aim of our study was to assess the efficacy and tolerability of IFN-alfa2b in combination with ribavirin in relapsers and nonresponders to high-dose IFN treatment (5 to 6 MU 3 times per week). We measured the biochemical and virologic responses to treatment and the risk for relapse during the 24 weeks following the end of treatment.

METHODS

Patients with chronic HCV infection (relapsers and nonresponders to a previous treatment with high-dose IFN) received IFN-alfa2b, 3 MU 3 times per week, and ribavirin, 1000 or 1200 mg/d for 24 or 48 weeks. The patients were then followed up for an additional 24 weeks. Sustained response was defined as normal serum alanine aminotransferase (ALT) level and undetectable HCV RNA 24 weeks after treatment was stopped.

RESULTS

Forty-three patients (32 men, 11 women; mean [SD] age, 45 [2] years; 10 relapsers, 33 nonresponders) were included in the study. Four patients were withdrawn from the study at week 4 of treatment because of treatment-related adverse events, and 1 dropped out. At the end of the treatment period, normalization of serum ALT levels and undetectable HCV RNA levels were seen in 58.1% and 30.2% of patients, respectively. No significant difference in virologic response at the end of treatment was found between nonresponders (10/33 [30.3%]) to previous IFN therapy and relapsers (3/10 [30.0%]). At the end of follow-up, 3 (7.0%) treated patients had sustained response (2 nonresponders to the first IFN course and 1 relapser). All of the patients with sustained response were treated for 24 weeks.

CONCLUSION

Based on the results of our study, combination therapy with IFN-alfa and ribavirin may be of value in a limited number of patients with chronic HCV infection who do not respond to, or relapse after, a first course of treatment with high-dose IFN monotherapy.

The Role of Interferon Gamma Gene Polymorphism (+874A/T, +2109A/G, and -183G/T) in Response to Treatment Among Hepatitis C Infected Patients in Fars Province, Southern Iran

BACKGROUND

Hepatitis C virus (HCV) infection as a worldwide health problem is associated with cirrhosis and hepatocellular carcinoma. With current treatment regimen, pegylated interferon (PEG-IFN) plus ribavirin, sustain virological response (SVR) is achieved in only 50% of infected individuals. In HCV infection, an inappropriate ratio of cytokines may affect the benefit of antiviral therapy. Given the polymorphisms in regulatory regions of cytokines genes may influence cytokines production.

OBJECTIVES

We aimed to investigate both the frequency of genotypes and alleles of interferon gamma (IFN-γ) gene at +874A/T, +2109A/G, and -183G/T loci in HCV-infected patients and their associations with response to therapy.

PATIENTS AND METHODS

A total of 158 patients were included and treated with PEG-IFN plus ribavirin. The presence of HCV infection in patients was confirmed by reverse transcription polymerase chain reaction, and genomic DNA was extracted from peripheral leukocytes using salting out method. IFN-γ gene polymorphisms were identified by polymerase chain reaction using sequence specific primers and restriction fragment length polymorphism analysis on genomic DNA.

RESULTS

Of 158 patients, 110 (69.5%) subjects achieved SVR and 48 (30.5%) subjects did not respond to therapy. The frequency of AA genotype (P = 0.001; OR: 11.2; CI: 2.26-63.21) and A allele (P = 0.01; OR: 3.23; CI: 1.23 8.56) of IFN-γ gene at +2109 locus were significantly different between the responder and non-responder subjects infected with genotype 1. Regardless of HCV genotype, the frequency of AG genotype was also higher in responder group than those who did not respond to therapy (P = 0.041; OR: 05.05; CI: 1.05-33.25)). In case of IFN-γ gene at +874 locus, there was no difference in genotypes and alleles frequencies between the responder and non-responder subjects infected with HCV genotypes 1 and 3. Haplotype analysis showed no association between haplotypes and response to therapy. All participants had G/T genotype at -183 locus.

CONCLUSIONS

Our findings indicate that heterogeneity at +2109 locus of IFN-γ gene but not at +874 locus could interfere with successful therapy in patients infected with HCV genotype 1.

Interferon for interferon nonresponding and relapsing patients with chronic hepatitis C

BACKGROUND

The widely-accepted treatment outcome for chronic hepatitis C is the sustained viral response (that is, no measurable viral RNA in blood six months after treatment). However, this surrogate outcome (as well as the previously employed biochemical and histologic ones) has never been validated. This situation exists because there are very few randomized clinical trials that have used clinical events (mortality or manifestations of decompensated cirrhosis) as outcomes, because those clinical events only occur after many years of infection. Patients in whom initial therapy fails to produce sustained viral responses do become potential candidates for retreatment; some of these individuals are not candidates for ribavirin or protease inhibitors and consideration could be given to retreatment with interferon alone.

OBJECTIVES

To assess the benefits and harms of interferon monotherapy retreatment in chronic hepatitis C patients and to validate the currently employed surrogate outcomes in this group of patients.

SEARCH METHODS

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until 16 August 2012.

SELECTION CRITERIA

Randomized trials comparing interferon versus placebo or no treatment in chronic hepatitis C nonresponders and relapsers to previous interferon.

DATA COLLECTION AND ANALYSIS

The primary outcomes were mortality (all-cause and hepatic), quality of life, and adverse events. Secondary outcomes were liver-related morbidity, sustained viral responses, biochemical responses, histologic improvements, and costs. We used both fixed-effect and random-effects model meta-analyses, reporting only the former if no difference existed.

MAIN RESULTS

Seven trials were identified. Two of them were at low risk of bias (the HALT-C and EPIC3 trials) and included 1676 patients. Both of these trials addressed the role of long-term low-dose pegylated interferon therapy in patients with severe fibrosis (demonstrated on liver biopsy) and were designed to assess the clinical outcomes. The remaining five trials included 300 patients and were at high risk of bias. Based on all trials reporting the outcomes, no significant difference was observed in either all-cause mortality (78/843 (9.3%) versus 62/867 (7.2%); risk ratio (RR) 1.30, 95% confidence interval (CI) 0.95 to 1.79; 3 trials) or hepatic mortality (41/532 (7.7%) versus 40/552 (7.2%); RR 1.07, 95% CI 0.70 to 1.63; 2 trials); however, when only the two trials at low risk of bias were combined, all-cause mortality was significantly higher in the recipients of the pegylated interferon (78/828 (9.4%) versus 57/848 (6.7%); RR 1.41, 95% CI 1.02 to 1.96) although trial sequential analysis could not exclude the possibility of random error. There was less variceal bleeding in the recipients of the interferon (4/843 (0.5%) versus 18/867 (2.1%); RR 0.24, 95% CI 0.09 to 0.67; 3 trials), although again trial sequential analysis could not exclude the presence of a type I error and the effect could not be confirmed in a random-effects model meta-analysis. No significant differences were seen with regard to the development of ascites, encephalopathy, hepatocellular carcinoma, or the need for liver transplantation. One trial reported quality of life data; the pain score was significantly worse in the recipients of the pegylated interferon. Adverse effects tended to be more common in the interferon recipients; the ones that were significantly more common included hematologic complications, infections, flu-like symptoms, and rash. The recipients of interferon had significantly more sustained viral responses (20/557 (3.6%) versus 1/579 (0.2%); RR 15.38, 95% CI 2.93 to 80.71; 4 trials) and a type I error was excluded by trial sequential analysis. The METAVIR activity score also improved (36/55 (65%) versus 20/46 (43.5%); RR 1.49, 95% CI 1.02 to 2.18; 2 trials). No significant differences were seen with regard to histologic fibrosis assessments.

AUTHORS' CONCLUSIONS

The clinical data were limited to patients with histologic evidence of severe fibrosis who were retreated with pegylated interferon. In this scenario, retreatment with interferon did not appear to provide significant clinical benefit and, when only the trials at low risk of bias were considered, retreatment for several years may even have increased all-cause mortality. Such treatment also produced adverse events. On the other hand, the treatment did result in improvement in some surrogate outcomes, namely sustained viral responses and histologic evidence of inflammation. Interferon monotherapy retreatment cannot be recommended for these patients. No clinical data are available for patients with less severe fibrosis. The sustained viral response cannot be used as a surrogate marker for hepatitis C treatment in this clinical setting with low sustained viral response rates and needs to be validated in others in which higher sustained viral response rates are reported.

Ribavirin plus interferon versus interferon for chronic hepatitis C

BACKGROUND

Hepatitis C is a major cause of liver-related morbidity and mortality. Standard therapy is ribavirin plus pegylated interferon to achieve undetectable level of virus in the blood, but the effect on clinical outcomes is controversial.

OBJECTIVES

To assess the beneficial and harmful effects of ribavirin and interferon combination therapy versus interferon monotherapy for chronic hepatitis C.

SEARCH STRATEGY

We identified trials through electronic databases, manual searches of bibliographies and journals, approaching authors of trials, and pharmaceutical companies until March 2009.

SELECTION CRITERIA

We included randomised trials, irrespective of blinding, language, or publication status, comparing ribavirin plus interferon versus interferon for treatment of chronic hepatitis C.

DATA COLLECTION AND ANALYSIS

The primary outcome measures were serum sustained loss of hepatitis C virus, liver-related morbidity plus all-cause mortality, and adverse events. We performed subgroup analyses of patients who were naive, relapsers, or non-responders to previous antiviral treatment. All outcomes were analysed with the random-effects model. We used Peto odds ratios (OR) with 95% confidence intervals (CI) for analysis of morbidity plus mortality. The remaining outcomes were presented as relative risks (RR). We used trial sequential analyses to examine the robustness of our findings.

MAIN RESULTS

We included 83 randomised trials with 12,707 patients. Most trials had unclear or high risk of bias. We did not find any significant influence of bias on our results but cannot exclude outcome measure reporting bias as many trials did not report on the primary outcomes of this review. Compared with interferon, ribavirin plus interferon had a significant beneficial effect on sustained virological response in subgroups of naive patients (RR 0.72, 95% confidence interval (CI) 0.68 to 0.75), relapsers (RR 0.62, 95% CI 0.54 to 0.70), non-responders (RR 0.89, 95% CI 0.84 to 0.93), and in all patients (RR 0.75, 95% CI 0.71 to 0.79). Combination therapy significantly reduced morbidity plus mortality in all patients (Peto OR, 0.43, 95% CI 0.23 to 0.79), but not in naive, relapsers, or non-responders individually. Combination therapy significantly increased the risk of haematological, dermatological, gastrointestinal, infectious, and miscellaneous (cough, dyspnoea, fatigue) adverse reactions. Accordingly, combination therapy significantly increased the risk of treatment discontinuation and dose reductions. Trial sequential analyses confirmed our findings regarding virological effects, but not regarding liver-related morbidity and all-cause mortality.

AUTHORS' CONCLUSIONS

Compared with interferon alone, ribavirin plus interferon is more effective in clearing hepatitis C virus from the blood. Combination therapy may reduce liver-related morbidity and all-cause mortality, but we need more evidence. The number needed to treat to obtain a beneficial effect is considerable considering the increased risk of several severe adverse reactions and costs.

Ribavirin monotherapy for chronic hepatitis C

BACKGROUND

Hepatitis C is a major cause of liver-related morbidity and mortality. A high proportion of patients never experience symptoms. Peginterferon plus ribavirin is the recommended treatment for chronic hepatitis C. However, ribavirin monotherapy may be considered for some patients.

OBJECTIVES

To assess the beneficial and harmful effects of ribavirin monotherapy for patients with chronic hepatitis C.

SEARCH STRATEGY

We identified trials through electronic databases, manual searches of bibliographies and journals, authors of trials, and pharmaceutical companies until March 2009.

SELECTION CRITERIA

We included all randomised trials irrespective of blinding, language, or publication status comparing ribavirin versus no intervention, placebo, or interferon for chronic hepatitis C.

DATA COLLECTION AND ANALYSIS

The primary outcome measures were serum sustained virological response (loss of hepatitis C virus RNA at least six months after treatment), liver-related morbidity plus all-cause mortality, and adverse events. Secondary outcome measures were end of treatment virological response, biochemical response (transaminase activity), and histological response. Randomisation methods, blinding, data handling, and funding were extracted as measures of bias control. Random-effects and fixed-effect meta-analyses were performed for all outcomes. We only present the results of the fixed-effect model if both models provide the same result regarding statistical significance. We present data as risk difference (RD) with 95% confidence intervals (CI).

MAIN RESULTS

We included 14 randomised trials with 657 patients. The majority of trials had unclear control of bias. Compared with placebo or no intervention, ribavirin had no significant effect on the sustained virological response (RD 0%, 95% CI -2% to 3%, five trials) or end of treatment virological response (RD 0% 95% CI -3% to 3%, ten trials). Ribavirin had no significant effect on liver-related morbidity plus mortality (RD 0%, 95% CI -2% to 3%, 11 trials). Ribavirin significantly increased the risk of adverse reactions, including anaemia. Ribavirin significantly improved end of treatment biochemical and histological response but not the sustained biochemical response. Ribavirin was significantly inferior to interferon regarding virological and biochemical responses (five trials).

AUTHORS' CONCLUSIONS

Ribavirin seems without beneficial effects on serum virological response and liver-related morbidity or mortality, and significantly increased the risk of adverse reactions. Ribavirin monotherapy seems significantly inferior to interferon monotherapy. The total number of included patients is small, and more trials are perhaps needed. The use of ribavirin monotherapy for chronic hepatitis C cannot be recommended outside randomised trials.

WITHDRAWN: Ribavirin with or without alpha interferon for chronic hepatitis C

BACKGROUND

Hepatitis C is a major cause of liver-related morbidity and mortality. Ribavirin plus interferon combination therapy is presently considered the optimal treatment of interferon naive patients with chronic hepatitis C, but its role in relapsers and non-responders to previous interferon therapy is not established.

OBJECTIVES

To assess the efficacy and safety of ribavirin alone or in combination with alpha interferon in interferon naive patients, relapsers, and non-responders with chronic hepatitis C.

SEARCH STRATEGY

Eligible trials were identified through searches on electronic databases: The Cochrane Hepato-Biliary Group Controlled Trials Register (August 2001), The Cochrane Controlled Trials Register on The Cochrane Library Issue 3, 2001, MEDLINE (1966 - August 2001), and EMBASE (1985 - August 2001). Manual searches of bibliographies and journals were done as well as authors of trials and pharmaceutical companies producing ribavirin or interferon were contacted.

SELECTION CRITERIA

We included all randomised trials comparing ribavirin with or without alpha interferon versus no intervention, placebo, or alpha interferon for chronic hepatitis C.

DATA COLLECTION AND ANALYSIS

The primary outcome measures were the 'sustained' (six months after treatment) virological response, and morbidity plus mortality. The secondary outcome measures were the 'end of treatment' and 'sustained' biochemical response, the 'end of treatment' virologic response, histology, quality of life, and adverse events.

MAIN RESULTS

We included eight trials in which 271 patients were randomised to ribavirin versus placebo or no intervention and 48 trials in which 6585 patients were randomised to interferon with or without ribavirin. Compared with placebo or no intervention, ribavirin monotherapy had no significant effect on the virological response or histology and only a transient effect on the biochemical response. Compared with interferon, combination therapy reduced the risk of not having a sustained virological response by 26% in naive patients (relative risk (RR) 0.74; 95% confidence interval (CI) 0.70-0.78), 33% in relapsers (RR 0.67; 95% CI 0.57-0.78), and 11% in non-responders (RR 0.89; 95% CI 0.83-0.96). There was no significant effect on morbidity plus mortality (Peto odds ratio 0.45; 95% CI 0.19-1.06). Irrespective of previous therapy, combination therapy significantly reduced the risk of not having a sustained biochemical response (RR 0.76; 95% CI 0.59-0.84) or improved histology (RR 0.67; 95% CI 0.56-0.81). Combination therapy also significantly increased the risk of treatment discontinuation (RR 1.28; 95% CI 1.07-1.52) and several types of adverse events.

AUTHORS' CONCLUSIONS

Combination therapy increased the number of naive patients, relapsers, and non-responders with a sustained virological, biochemical, or histological response, but also the occurrence of adverse events.

Treatment and retreatment in patients with chronic hepatitis C: 10 years clinical practice in a single centre

AIM

Therapy for chronic hepatitis C (HCV) has mainly been evaluated in large clinical, select population, trials. We sought to evaluate whether prognostic factors of therapeutic response are similar in clinical practice, where treated population is more diverse.

METHODS

Retrospective study of HCV-infected patients who completed >6 months of treatment/retreatment with various therapeutic regimens, in a single reference centre over a 10-year period. Adjuvant treatment with hemopoetic growth factors was used when warranted by treatment side effects.

RESULTS

Overall, 77/125 patients (61.6%) achieved sustained virological response (SVR). Fifty-four naïve patients (43.2%) achieved SVR; 19 (26%) with interferon-alpha (IFN-alpha), 13 (59.1%) with IFN-alpha and ribavirin, and 22 (73.3%) with pegylated IFN-alpha and ribavirin. Seventeen patients responded after two courses of therapy and six after more than three courses, achieving a total SVR of 32%. Patients with genotype-1 were less probable to achieve SVR [odds ratio (OR)=6.23], while younger patients were more possible to achieve SVR, OR=0.97. Most non-responders after >2 regimens were genotype-1 patients (90%).

CONCLUSIONS

In clinical practice, where strict selection criteria cannot be applied, genotype-1 remains the most significant prognostic factor of response failure. Addition of adjuvant hemopoetic growth factors, when warranted, may increase compliance and thus overall SVR.

Follow-up studies of treatment for hepatitis C virus infection among injection drug users

Physicians are reluctant to treat chronic hepatitis C virus (HCV) infection in active injection drug users (IDUs). An important reason for this is concern about reinfection after successful treatment. However, little is known about this apparent risk; because of lack of protective immunity, reinfection with HCV seems possible. Here, I discuss several cases of probable reinfection in IDUs, 2 of which occurred during or after successful treatment for HCV infection. In a Norwegian trial, 69 IDUs who had abstained from drug use for >or=6 months were treated for HCV infection; of these, 27 tested negative for HCV RNA at 6 months of follow-up (sustained virological response). At 5 years of follow-up, 9 (33%) of the 27 IDUs with sustained virological response had returned to drug use, but only 1 case of reinfection was observed. In another study, 395 subjects with sustained virological response were followed with yearly testing for HCV RNA. Although injection drug use was the route of HCV transmission in 40% of the subjects, only 7 (2%) experienced a late relapse of HCV infection. It has not been determined whether any of these cases were actual reinfections. Available data suggest that the rate of long-term response to treatment for HCV infection is excellent in IDUs.

Combination Therapy of Interferon and Ribavirin Versus Interferon Monotherapy in Treatment of Chronic Hepatitis C: A Meta-analysis of Clinical Trials

This meta-analysis was conducted to assess the efficacy and safety of interferon and ribavirin combination therapy (CT) versus interferon monotherapy (IMT) in inducing sustained response in interferon-naïve, relapser, and nonresponder chronic hepatitis C patients. A literature search was performed using the MEDLINE database for clinical trials published in the period between 1995 and 2003. A total of 31 randomized trials and 7 nonrandomized trials comparing CT with interferon alone or comparing different dose regimens of CT were included in this meta-analysis. The primary outcome measure was sustained virological response. The summary estimate of the odds ratio was obtained using the random effect model. The study showed that sustained virological response rate was significantly higher in interferon-naïve, relapser, and nonrespondent chronic hepatitis C patients who were on CT compared to IMT (odds ratio = 3.23, 17.65, and 4.71, respectively). There was no statistically significant difference in virological and biochemical responses between different dose regimens of CT. Side effects, dose reduction, and treatment discontinuation rates were significantly higher in patients receiving CT compared with IMT. Treatment with interferon plus ribavirin has a significant benefit on the virological and biochemical response in patients with chronic hepatitis C irrespective to the previous treatment, and it should be considered the treatment of choice in naïve, relapser, and nonrespondent chronic hepatitis C patients.

Treatment of Relapsers after Combination Therapy for Chronic Hepatitis C

Sustained virologic response rates are significantly higher in patients who have relapsed after a previous course of therapy compared with patients who did not respond. A meta-analysis of combination therapy in patients who failed IFN monotherapy reported SVR rates of 52% in relapsers to prior therapy and 16% in nonresponders. Similarly, relapsers after combination standard IFN and RBV therapy have higher SVR rates than combination of therapy nonresponders when treated with pegylated interferon and ribavirin. For this reason, patients who relapse after a previous course of therapy should be considered potential candidates for retreatment. Factors that have been associated with SVR in these patients include genotype non-I, low viral loads, and lesser degrees of fibrosis. The course of treatment in all patients who have relapsed after prior therapy should be reviewed to identify possible reasons for failure to achieve an SVR. In particular, optimal dosing of PEG IFN and RBV and the occurrence and timing of treatment dose reductions during prior therapy should be reviewed. The reasons for dose reduction should be addressed before initiating another course of therapy in an effort to optimize the chance for a SVR. Patients who had dose reduction for depression, anemia, or neutropenia, should be considered for antidepressants, erythropoietin, or, if neutropenia is severe, granulocyte colony stimulating factor therapy, respectively, during retreatment. Prolongation of therapy beyond 48 weeks in patients with relapse after a standard course of PEG IFN and RBV may offer a chance of SVR. Novel agents currently in development, including protease and polymerase inhibitors, may prove to be therapeutic options for these patients in the future.

A randomized trial of pegylated interferon alpha-2b plus ribavirin in the retreatment of chronic hepatitis C

OBJECTIVES

The efficacy of combination therapy with pegylated interferon (PEG IFN) alpha plus ribavirin (RBV) in the retreatment of chronic hepatitis C (CHC) in patients who previously failed combination standard IFN plus RBV or IFN monotherapy has not been well established.

METHODS

Three hundred and twenty-one CHC patients including virologic nonresponders to combination IFN plus RBV (n = 219) or IFN monotherapy (n = 47), and relapsers to combination therapy (n = 55) were randomized to receive PEG IFN alpha-2b 1.5 microg/kg per wk plus RBV 800 mg per day (Regimen A, n = 160) or PEG IFN alpha-2b 1.0 microg/kg per wk plus RBV 1,000-1,200 mg per day (Regimen B, n = 161) for 48 wks.

RESULTS

Sustained virologic response (SVR) occurred in 16% of the overall study population (Regimen A vs B, 18%vs 13%, p= 0.21), in 8% of the combination therapy nonresponders (10%vs 6%, p= 0.35), in 21% of the IFN monotherapy nonresponders (16%vs 27%, p= 0.35), and in 42% of the combination therapy relapsers (50%vs 32%, p= 0.18). In nonresponders to prior combination therapy, HCV ribonucleic acid levels <100,000 copies/mL at the end of the prior treatment course were associated with an increased SVR compared with levels >or=100,000 copies/mL (21%vs 5%, p= 0.002). In the overall study population, genotype 1 patients had lower SVR rates than others (14%vs 33%, p= 0.01), and African Americans had lower SVR than Caucasians (4%vs 18%, p= 0.01).

CONCLUSION

Combination therapy with PEG IFN alpha-2b plus RBV is more effective in patients who relapsed after combination standard IFN plus RBV than in nonresponders to either combination therapy or IFN monotherapy. There was no significant effect of dosing regimen.

Ribavirin monotherapy for chronic hepatitis C

BACKGROUND

Hepatitis C is a major cause of liver-related morbidity and mortality. The disease progresses without symptoms for several decades. Ribavirin monotherapy may represent a treatment for some patients.

OBJECTIVES

To assess the beneficial and harmful effect of ribavirin monotherapy for patients with chronic hepatitis C.

SEARCH STRATEGY

We identified trials through electronic databases, manual searches of bibliographies and journals, authors of trials, and pharmaceutical companies until May 2005.

SELECTION CRITERIA

We included all randomised trials irrespective of blinding, language, or publication status comparing ribavirin versus no intervention, placebo, or interferon for chronic hepatitis C.

DATA COLLECTION AND ANALYSIS

The primary outcome measures were the six months sustained loss of hepatitis C virus RNA in blood after end of treatment and liver-related morbidity plus all-cause mortality. Secondary outcome measures were end of treatment virological response, biochemical response, histological response, and adverse events. Random- and fixed-effects meta-analyses with 95% confidence intervals (CI) were performed for all outcomes. We used Peto odds ratios (OR) for analysis of morbidity plus mortality and relative risks (RR) for the remaining outcomes.

MAIN RESULTS

We identified 13 randomised trials including 594 patients with chronic hepatitis C. Most trials had low methodological quality. Compared with placebo/no intervention, ribavirin had no significant effect on sustained (RR 1.01, 95% CI 0.96 to 1.07, five trials) or end of treatment virological response (RR 1.00, 95% CI 0.94 to 1.07, ten trials). Ribavirin had no significant effect on liver-related morbidity plus mortality (Peto OR 1.96, 95% CI 0.20 to 19.0, eleven trials). Ribavirin significantly improved end of treatment biochemical and histological response but not sustained biochemical response. Further, ribavirin significantly increased the risk of anaemia. Ribavirin was significantly inferior to interferon regarding virological and biochemical response (four trials).

AUTHORS' CONCLUSIONS

We found that ribavirin versus placebo/no intervention had no significant beneficial effect on virological response and liver morbidity, but may improve biochemical and histological response transiently. Ribavirin increased the risk of anaemia. Therefore, we cannot recommend ribavirin monotherapy for patients with chronic hepatitis C outside randomised trials.

Ribavirin plus interferon versus interferon for chronic hepatitis C

BACKGROUND

Hepatitis C is a major cause of liver-related morbidity and mortality. The disease progresses without symptoms for several decades and most patients are diagnosed based on the presence of hepatitis C virus ribonucleic acid and elevated transaminases.

OBJECTIVES

To assess the beneficial and harmful effects of ribavirin and interferon combination therapy versus interferon monotherapy for chronic hepatitis C.

SEARCH STRATEGY

We identified trials through electronic databases, manual searches of bibliographies and journals, approaching authors of trials and pharmaceutical companies, until May 2004.

SELECTION CRITERIA

We included randomised trials, irrespective of blinding, language, or publication status, comparing ribavirin plus interferon versus interferon alone for treatment of chronic hepatitis C.

DATA COLLECTION AND ANALYSIS

The primary outcome measures were the sustained loss of hepatitis C virus and liver-related morbidity plus all-cause mortality. We separately analysed patients who were naive, relapsers, or non-responders to previous antiviral treatment. Random-effects and fixed-effect model meta-analyses were performed for all outcomes. We used Peto odds ratios (OR) with 95% confidence intervals (CI) for analysis of morbidity plus mortality. The remaining outcomes were presented as relative risks (RR).

MAIN RESULTS

We included 72 randomised trials with 9991 patients. Most trials had low methodological quality but we did not find any significant influence of quality on our results. Compared with interferon, combination therapy had a significant beneficial effect on sustained virological response (RR 0.73, 95% CI 0.71 to 0.75) and in subgroups of naive patients (RR 0.72, 95% CI 0.68 to 0.76), relapsers (RR 0.63, 95% CI 0.54 to 0.73), and non-responders (RR 0.89, 95% CI 0.84 to 0.94) individually. Combination therapy significantly reduced morbidity plus mortality (Peto OR 0.46, 95% CI 0.22 to 0.96), but not in naive, relapsers, or non-responders individually. Combination therapy also had a significant beneficial effect on the histological response. Combination therapy significantly increased the risk of anaemia (RR 10.48, 95% CI 5.34 to 20.55), which occurred in 22% of patients on combination therapy. Combination therapy also significantly increased the risk of dermatological, gastrointestinal, infectious, and miscellaneous (cough, dyspnea, fatigue) adverse events. Accordingly, combination therapy significantly increased the risk of treatment discontinuation (RR 1.19, 95% CI 1.01 to 1.39).

AUTHORS' CONCLUSIONS

Compared with interferon alone, ribavirin plus interferon is more effective in clearing hepatitis C virus and improving liver histology. This may lead to reduced morbidity and mortality. However, combination therapy significantly increased the risk of several adverse events.

A randomized trial of prolonged high dose of interferon plus ribavirin for hepatitis C patients nonresponders to interferon alone

Retreatment of chronic hepatitis C patients nonresponders to interferon (IFN) alone with the standard dose of IFN [3 million units (MU) thrice weekly (TIW)] plus ribavirin for 24 weeks has yielded low sustained virological response (SVR), averaging 8%. The aim of the present, open-labelled, randomized study was to evaluate the efficacy of IFN induction therapy followed by prolonged high dose of IFN plus ribavirin in nonresponders. One hundred and fifty-one patients were randomized to receive 5 MU daily of IFN alfa-2b (group 1, n = 73) or 5 MU TIW of IFN alfa 2b (group 2, n = 78) for 4 weeks followed by IFN (5 MU TIW) plus ribavirin (1000/1200 mg/daily) for 48 weeks in both groups. In an intention-to-treat analysis, the sustained virological response (SVR) at 24-week follow-up was 33 and 23% for group 1 and 2, respectively (P = 0.17). The overall SVR was 52 and 18% in patients with genotype 2/3 and 1/4, respectively. Among genotype 1/4 patients the SVR was 29 and 11% for age younger or older than 40 years. Compared with genotype 2/3 patients, the risk (95% confidence interval) of nonresponse to retreatment was 3.0-fold (1.17-8.0) in younger genotype 1/4 patients and 8.4-fold (3.0-23.29) in older genotype 1/4 patients. In conclusion these results suggest that retreatment with a reinforced regimen should be focused in nonresponder genotype 2/3 patients and younger genotype 1/4 patients, who are most likely to benefit. Induction therapy does not improve SVR.

Treatment of relapsers after combination therapy for chronic hepatitis C

A significant number of patients with chronic hepatitis C relapse after treatment. As therapy for CHC has improved over the last decade, the issue of retreating patients who did not achieve a sustained virologic response with previous treatment regimens frequently arises. Several studies have assessed the efficacy of pegylated interferon (IFN) and ribavirin (RBV) combination therapy in IFN and RBV therapy relapsers. Patients who have relapsed after therapy have significantly higher SVR rates than those who are nonresponders to therapy and should be considered candidates for retreatment. Predictors of a favorable response to therapy in naïve patients appear to also predict response to therapy in patients who have relapsed previously.

Ribavirin increases mitogen- and antigen-induced expression of CD40L on CD4+ T cells in vivo

Here, CD40L expression and cytokine production have been analysed in peripheral blood cells from orthotopic liver transplantation (OLT) recipients treated with ribavirin for recurrent chronic hepatitis C. The study included 18 OLT recipients treated with ribavirin, eight control OLT recipients and 10 healthy controls. FACS analysis showed that baseline expression of CD40L was not different between ribavirin-treated patients and controls. In contrast, after stimulation with both HCV core antigen and phorbol myristate acetate (PMA) plus ionomycin (IO), the expression of CD40L on CD4 lymphocytes was significantly higher in the ribavirin group compared with controls. In the ribavirin group, the increased expression of CD40L significantly correlated with reduction of HCV RNA levels with respect to pretreatment values. Finally, ribavirin treatment was not associated with modification of PMA-IO-induced cytokine production by T lymphocytes and interleukin (IL)-1beta and tumour necrosis-alpha (TNF)-alpha production by CD40L-stimulated monocytes. In conclusion, these data indicate that ribavirin -upmodulates CD40L expression on CD4 T cells, a property which may account in part for its ability to enhance the antiviral activity of interferon-alpha in the treatment of chronic HCV infection.

Meta-analysis: combination therapy with interferon-alpha 2a/2b and ribavirin for patients with chronic hepatitis C previously non-responsive to interferon

BACKGROUND

The efficacy of interferon-alpha plus ribavirin treatment for patients not responding to interferon monotherapy is not well established.

AIM

To assess the efficacy and safety of combination therapy with interferon-alpha 2a/2b plus ribavirin by performing a meta-analysis of randomized clinical trials.

METHODS

A systematic search of electronic databases for randomized clinical trials of interferon-alpha 2a/2b plus ribavirin was conducted independently by two investigators. Data abstraction was performed. The primary end-point was a sustained virological response. Estimates of the common odds ratio were calculated using a random effects model.

RESULTS

Of the 127 identified studies, 46 were considered for evaluation and 10 were included (1728 patients). The pooled sustained virological response was 12.6% (95% CI, 9.5-16.3%) for combination therapy vs. 2% (95% CI, 0.9-4.0%) for interferon monotherapy, with a common odds ratio of 5.49. Higher doses of interferon, a longer duration of therapy (48 weeks) and genotypes other than 1 and 4 were associated with an improvement in response. More side-effects and discontinuations were observed with combination therapy than with interferon monotherapy.

CONCLUSIONS

Non-responders to interferon may benefit from re-treatment with combination therapy, especially from a 48-week regimen.

Meta-analysis: ribavirin-induced haemolytic anaemia in patients with chronic hepatitis C

AIM

To use meta-analysis to study the risk of anaemiarelated to ribavirin therapy for chronic hepatitisC.

METHODS

The MEDLINE database up to January 2001 was searched for randomized controlled trials of ribavirin (monotherapy or combined with interferon) for chronic hepatitis C. The outcomes evaluated were withdrawal from the study due to anaemia, ribavirin dosage reduction due to a decrease in haemoglobin and haemoglobin levels below 10 g/dL.

RESULTS

Based on 17 studies, the overall risk difference (ribavirin vs. no ribavirin) for anaemia was 0.09 [95% confidence interval (CI), 0.04-0.13]. Two Asian studies reported risk differences of 0.29 and 0.22, greater than the pooled risk difference of 0.07 (95% CI, 0.03-0.12) for 15 non-Asian studies. The risk associated with 1 g or more of ribavirin per day was higher (risk difference, 0.09; 95% CI, 0.04-0.14) than that for 0.8 g of ribavirin per day (risk difference, 0.01; 95% CI, - 0.04-0.06).

CONCLUSIONS

Chronic hepatitis C patients treated with 1 g or more of ribavirin per day were at a higher risk of developing anaemia. Reported risks were higher among Asian studies, which may be due to differences in study entrance criteria, dosage titration strategy or ethnic vulnerability.

Interferon for interferon nonresponding and relapsing patients with chronic hepatitis C

BACKGROUND

Interferon monotherapy leads to sustained virologic clearance in a minority of patients with chronic hepatitis C. Studies have yielded conflicting results regarding retreatment with interferon in nonresponders and relapsers.

OBJECTIVES

To assess the beneficial and harmful effects of retreatment with interferon in chronic hepatitis C nonresponders and relapsers to previous interferon treatment.

SEARCH STRATEGY

Trials were identified through electronic databases, manual searches, authors, and pharmaceutical companies (August 2001).

SELECTION CRITERIA

Randomised trials comparing interferon versus control or different interferon regimens in chronic hepatitis C patients being nonresponders and relapsers to previous interferon were included.

DATA COLLECTION AND ANALYSIS

The primary outcome was failure to achieve a sustained virologic response defined as positive serum hepatitis C virus RNA at least six months following treatment. Secondary outcomes included liver-related morbidity, mortality, biochemical responses, adverse events, and histology.

MAIN RESULTS

Ten randomised trials involving 686 nonresponders and eight trials involving 484 relapsers were included; their methodological quality was poor. In nonresponders, interferon reduced the risk of not achieving an end of treatment biochemical response compared with no treatment (relative risk [RR] 0.77, 95% confidence interval [CI] 0.66 to 0.91); however, virologic responses were not reported. In a post hoc subgroup analysis, doses greater than 3 million units (MU) three times weekly offered no advantage compared with 3 MU three times weekly for biochemical sustained response. Failure to obtain a virologic sustained response was less likely with 48 than 24 weeks of therapy (RR 0.87, 95% CI 0.79 to 0.96). Adverse events did not differ significantly regardless of treatment dose or duration. In relapsers, none of the trials compared interferon with no treatment. In a post hoc analysis, doses greater than 3 MU three times weekly were no more effective in achieving a virologic sustained response than 3 MU three times weekly. Compared with 24 weeks, treatment durations of 48 weeks were less likely to fail to achieve a virologic sustained response (RR 0.69, 95% CI Random 0.51 to 0.95), but associated with more frequent dosage reduction (RR 9.07, 95% CI 1.20 to 68.63). No data regarding clinical outcomes or histology was available in either patient group.

REVIEWER'S CONCLUSIONS

Retreatment with interferon leads to sustained virologic clearance in a minority of chronic hepatitis C patients with nonresponse or relapse following interferon monotherapy. Treatment durations of 48 weeks are superior to 24 weeks, but doses greater than 3 MU three times weekly are no more effective. No data exists regarding the effect on clinical outcomes.

Treatment of chronic hepatitis C in injecting drug users: 5 years' follow-up

AIM OF THE STUDY

To assess the long-term hepatitis C (HCV) treatment outcome in former injecting drug users (IDUs).

MATERIALS AND METHODS

A long-term follow-up of 27 former IDUs who had been successfully treated for chronic hepatitis C was performed. These patients represented all IDUs who had obtained a sustained virological response in a Norwegian HCV treatment trial. The patients had been treated with interferon-alpha alone or in combination with ribavirin. At 5 years' follow-up the 27 IDUs were retested for HCV RNA and risk behaviour for HCV transmission after treatment was assessed. In the control group all 18 non-IDUs who had obtained a sustained virological response in the same treatment trial were included.

RESULTS

At follow-up 13-82 months (median 64) after the end of treatment only one case of probable reinfection was seen among the 27 IUDs. No reoccurrence of HCV was observed in the control group. The IDU who was HCV RNA positive at follow-up had continued injecting drugs and reported frequent needle sharing. At follow-up HCV of genotype 1a was detected in contrast to genotype 1b before treatment indicating that this patient was reinfected with HCV. A return to injecting drug use occurred in 9 (33%) of 27 IDUs.

CONCLUSION

The long-term outcome of HCV treatment in former IDUs was excellent. Despite frequent reinitiation of drug injection all but 1 remained HCV RNA negative.

Effect of HCV viral dynamics on treatment design: lessons learned from HIV

Viral load measurements provide an indication of viral replication, and thereby serve as a valuable tool to guide the initiation of therapy and subsequent changes. Plasma human immunodeficiency viral load strongly predicts the rate of decrease in CD4+ lymphocyte count, and progression to AIDS and death. Furthermore, the efficacy of antiretroviral therapy can be assessed by monitoring changes in plasma human immunodeficiency viral load. Similarly, viral load provides valuable information about the natural history of the hepatitis C virus infection. Hepatitis C viral load can be used to predict the likelihood of response to standard interferon-alpha treatment and other interferon-alpha regimens and to monitor treatment efficacy. Increased understanding of the natural history of the hepatitis C virus infection and the nature of resistance to interferon-alpha therapy suggests that effective treatment regimens must maintain serum levels of interferon-alpha. Ideally, interferon-alpha serum levels should provide constant pressure on the virus and should prevent viral rebound, thereby avoiding continued viral replication and minimizing the potential for emergence of resistant quasi-species. Current regimens designed to address these points include early aggressive intervention, combination drug regimens, prolonged maintenance, and novel interferons. By enabling the design and rapid assessment of new treatment regimens, viral load measurement will revolutionize the clinical management of the hepatitis C virus infection, as it has the HIV.

High-dose prolonged combination therapy in non-responders to interferon monotherapy for chronic hepatitis C

BACKGROUND

Therapy of chronic hepatitis C non- responders to interferon monotherapy with standard doses of interferon plus ribavirin is usually ineffective.

AIM

To evaluate the efficacy and tolerability of high-dose prolonged combination retreatment in non- responder patients.

METHODS

Patients were retreated for 6 months with 6 MU alphaIFN on alternate days and 1000 or 1200 mg/day ribavirin. HCV-RNA negative patients continued therapy for an additional 6 months.

RESULTS

Forty patients (29 males, mean age 49.7 years, 34 genotype 1b, 11 with F3 fibrosis) were treated. At 6 months, 20 (50%) patients were HCV-RNA negative but six of them discontinued therapy because of adverse events. A sustained response was achieved in 28% of patients (11/40). A sustained response was more frequent among patients with genotype non-1b than in those with genotype 1b (67 vs. 21%, P=0.005) and clearance of HCV-RNA in the first 3 months had a high predictive value for sustained response (100% of sustained responders vs. 24% of non-responders, P=0.0001).

CONCLUSIONS

High-dose prolonged combination therapy in non-responders to IFN monotherapy leads to a higher rate of sustained response than the standard combination regimen. Tolerability may be a rate-limiting factor. Maximal effectiveness can be predicted in patients with non-1b genotype and in those who clear HCV-RNA soon after starting retreatment.

Treatment of patients with chronic hepatitis C not responding to interferon with high-dose interferon alpha with or without ribavirin: final results of a prospective randomized trial. Austrian Hepatitis Study Group

OBJECTIVE

To investigate the efficacy of high-dose interferon alpha (IFN-alpha) with or without ribavirin in interferon (IFN) non-responders.

STUDY DESIGN

304 chronic hepatitis C patients received 5 MU IFN-alpha2b (IntronA, Schering-Plough, Kenilworth, NJ, USA) three times a week for 3 months. Non-responders were randomized either to continue with IFN (IFN 5 MU/TIW followed by 10 MU/TIW, each for 3 months) alone (group A: n = 76, m: f = 54: 22, age 45.7 +/- 12 years, 16% cirrhosis, alanine aminotransferase [ALT] 66 +/- 35 U/l) or in combination with ribavirin (approximately 14 mg/kg/day) (group B: n = 81, m: f = 57: 24, age 48.2 +/- 12 years, 17% cirrhosis, ALT 71 +/- 40 U/l). At the end of treatment, patients were followed for 6 months.

MAIN OUTCOME MEASURES

Virological response at end of treatment and 6 months thereafter.

SETTING

University hospitals and tertiary referral centres.

RESULTS

At the end of treatment, eight (10.8%) and 25 (31.3%, P= 0.0066) patients were HCV-RNA negative, and 51 and 39 were HCV-RNA positive, in groups A and B, respectively. There were 17 drop-outs in each group. Six months after treatment, only one patient in group A (1.3%) and seven patients (8.6%, P= 0.06) in group B had normal ALT and undetectable serum HCV-RNA.

CONCLUSIONS

A combination of high-dose IFN with ribavirin induces a short-lasting complete response in about one-third of IFN-non-responders.

Efficacy of high-dose interferon in combination with ribavirin in patients with chronic hepatitis C resistant to interferon alone

OBJECTIVE

Interferon combined with ribavirin has efficacy in the treatment of patients with chronic hepatitis C virus (HCV) infection. However, its utility in patients who have not responded to prior interferon therapy is not clear. Furthermore, the effect of using an increased dose of interferon in combination with ribavirin in patients with chronic hepatitis C resistant to conventional doses of interferon is not known. The aim of our study was to evaluate the effect of high-dose interferon in combination with ribavirin on the efficacy of treating patients with chronic hepatitis C resistant to interferon monotherapy in a large multicenter trial.

METHODS

We randomized 154 patients with chronic hepatitis C who failed to achieve a sustained response with prior interferon therapy to receive either 3 or 5 MU of interferon alpha-2b and ribavirin (1000-1200 mg/day) for 12 months. There were 119 patients who had not responded and 35 who initially responded but relapsed after prior interferon monotherapy. Serum HCV RNA levels were measured at entry, 6, and 12 months of treatment and at the end of a 6-month follow-up period.

RESULTS

The mean age of the subjects was 47 yr (range 28-68 yr), and 110 (71.4%) were men. One hundred thirty-two patients (86%) had HCV genotype 1, whereas 21 (14%) had cirrhosis. Eighty-one subjects (53%) were randomized to receive 3 MU of interferon alpha-2b. Fifteen of 35 relapse subjects (43%) and 12 of 119 prior nonresponder entrants (10%) achieved a sustained virological response to the 12-month course of treatment. Overall, 11 of 81 patients (14%) receiving 3 MU, and 16 of 73 patients (22%) receiving 5 MU of interferon maintained an undetectable HCV RNA level after cessation of therapy. The difference in sustained response rates between the two interferon dosage groups did not reach statistical significance (p = 0.09). However, among the nonresponder patients alone, there was an increased sustained response in the high-dose interferon group compared with the standard interferon dose group (15.5% vs 4.9%, p = 0.055). Twenty-six patients discontinued therapy before 6 months, including 10 patients (12.3%) in the 3-MU and 16 patients (21.9%) in the 5-MU groups (p = 0.17).

CONCLUSIONS

Sustained virological response to combined interferon alpha-2b and ribavirin was significantly higher in relapse patients than those who did not respond to prior interferon monotherapy. Although, when all treated patients were analyzed, there was no significant difference in sustained response between subjects receiving 3 and 5 MU of interferon, among the prior nonresponder patients, treatment with 5 MU of interferon with ribavirin resulted in a slightly increased response compared with treatment with the standard interferon dosage. The tolerability of the treatment regimens was comparable.

Treatment with ribavirin and interferon-alpha reduces interferon-gamma expression in patients with chronic hepatitis C

Recent studies in vitro and in animals have suggested that ribavirin may potentiate the antihepatitis C virus (HCV) activity of interferon-alpha (IFN-alpha) by up-modulating the production of T cell-derived cytokines, such as interleukin (IL)-2 and IFN-gamma, which play a key role in the cellular immune response against HCV. To study the immune-modulatory mechanisms of ribavirin further, cytokine production by activated T cells and circulating cytokine levels were studied by FACS analysis and ELISA testing in 25 patients with chronic hepatitis C unresponsive to IFN-alpha, before and after treatment with either ribavirin plus IFN-alpha or IFN-alpha alone. After 16 weeks of treatment, both the expression of IFN-gamma by activated T cells and the blood levels of IFN-gamma, were significantly reduced with respect to pretreatment values in patients treated with ribavirin and IFN-alpha but not in those undergoing treatment with IFN-alpha alone. The expression of IFN-gamma was significantly lower in patients that gained normal ALT levels with respect to those that did not. No modification of the expression of IL-2, IL-4 and IL-10 was found before and after treatment in either group of patients. In conclusion, the results of this study do not support up-modulation of IFN-gamma and IL-2 production as the mechanism by which ribavirin potentiates IFN-alpha anti HCV activity. In addition, our findings suggest that ribavirin may exert an anti-inflammatory effect and may help reducing IFN-gamma-driven T cell activation and liver damage.

Current therapy for chronic hepatitis C

Chronic hepatitis C virus infection is common in the United States with an estimated prevalence of 2.7 million persons. Fortunately, the incidence of new infections has markedly declined in recent years and the natural history of chronic hepatitis usually only results in significant progression after several decades of infection. However, the majority of chronically infected patients acquired their infections more than 20 years ago; these patients with long-standing chronic hepatitis are now presenting in increasing numbers with decompensated cirrhosis and the need for liver transplantation. Cirrhosis caused by chronic hepatitis C is now the most common indication for liver transplantation. Interferon monotherapy became clinically available 10 years ago but resulted in sustained improvement in liver disease and durable loss of detectable virus in fewer than 10% of treated patients. The recent use of the combination of interferon with the nucleoside analogue ribavirin for 6-12 months results in a sustained virological response in 30%-40% of previously untreated patients. The response to this combination therapy is also excellent in patients who had initially responded to interferon monotherapy and later relapsed. Furthermore, some recent studies suggest that a small proportion of patients who failed to respond to a prior course of interferon (primarily noncirrhotic patients with low levels of virus and genotypes other than 1) may also benefit from retreatment with this combination.