Peginterferon alfa-2a (40KD) (PEGASYS) plus ribavirin (COPEGUS) in retreatment of chronic hepatitis C patients, nonresponders and relapsers to previous conventional interferon plus ribavirin therapy

Cost-effectiveness analysis is a mandatory strategy for health systems: evidence from a study involving therapies for hepatitis C

Cost-effectiveness analysis is essential in health decision making. Several countries use it as synthesis of evidence to incorporate health technologies. The protease inhibitors (PI) boceprevir (BOC) and telaprevir (TVR) are indicated for chronic hepatitis C treatment and were incorporated in guidelines worldwide. Pre-marketing clinical trials showed higher sustained virological response rates in relation to previous therapies, but the incorporation of PIs generated a significant financial impact. The aim of this study was to discuss the relevance of cost-effectiveness analysis through a study that involved the inclusion of PIs in a clinical protocol. The analysis was part of a real-life study that included patients infected with hepatitis C virus genotype 1 treated in a tertiary university hospital in Brazil. Triple therapies (TT) with ribavirin (RBV), peginterferon α-2a (Peg-INF α-2a) and BOC or TVR were compared to dual therapy with RBV and Peg-INF α-2a. Sensitivity analysis of the cost-effectiveness ratio indicated an 88.2% chance of TTs presenting a higher cost per cure. The incremental cost-effectiveness ratios (ICER) exceeded the Brazilian gross domestic product (GDP) per capita by three times in all proposed scenarios. The sensitivity of ICER showed an 88.4% chance of TT not being cost-effective. The impact of PI incorporation was negative and the conduct about this could have been different if a previous cost-effectiveness analysis had been conducted.

Boceprevir for chronic HCV genotype 1 infection in patients with prior treatment failure to peginterferon/ribavirin, including prior null response

BACKGROUND & AIMS

Boceprevir with peginterferon/ribavirin (BOC/PR) leads to significantly higher sustained virological response (SVR) rates in patients with chronic hepatitis C and partial response or relapse after prior treatment with peginterferon/ribavirin. We studied the efficacy of BOC/PR in patients with prior treatment failure, including those with a null response (<2-log10 decline in HCV RNA), to peginterferon/ribavirin.

METHODS

Patients in the control arms of boceprevir Phase 2/3 studies who did not achieve SVR were re-treated with BOC/PR for up to 44 weeks. Patients enrolling >2 weeks after end-of-treatment in the prior study received PR for 4 weeks before adding boceprevir.

RESULTS

Of 168 patients enrolled, four discontinued from the PR lead-in and 164 received BOC/PR. Baseline viral load was >800,000 IU/ml in 77% of patients; 62% had HCV genotype 1a, and 10% were cirrhotic. In the ITT analysis (all 168 patients), SVR was achieved in 20 (38%) of 52 patients with prior null response, 57 (67%) of 85 with prior partial response, and 27 (93%) of 29 with prior relapse. In the mITT analysis (164 BOC/PR-treated patients), SVR rates were 41% (20/49), 67% (57/85), and 96% (27/28), respectively. SVR was achieved by 48% of patients with <1-log10 decline in HCV-RNA after lead-in and 76% of those with ⩾ 1-log10 decline or undetectable HCV-RNA after lead-in. The most common adverse events were anemia (49%), fatigue (48%), and dysgeusia (35%); 8% of patients discontinued due to adverse events.

CONCLUSIONS

Re-treatment with BOC/PR improved SVR rates in all patient subgroups, including those with prior null response.

Pegylated interferon and ribavirin in the retreatment of chronic hepatitis C in Korea

Background/Aims

Pegylated interferon (peginterferon) and ribavirin is the current standard therapy for chronic hepatitis C. The aims of this study were to evaluate the efficacy of peginterferon and ribavirin and to identify predictors of a sustained virological response (SVR) to the retreatment of chronic hepatitis C in Korea.

Methods

The clinical records of 91 patients with chronic hepatitis C who were retreated with peginterferon and ribavirin were retrospectively analyzed. None of the patients had previously attained a SVR, and the patients were categorized according to their previous responses (nonresponder, relapser, or inadequate treatment) to conventional interferon/ribavirin.

Results

The overall SVR rate was 54.9%. Independent predictors of a SVR were genotypes 2 and 3, relapse, an adherence to peginterferon of over 80%, and an early virological response (EVR). For genotype 1 patients, an adherence to peginterferon of over 80% was an independent predictor of a SVR.

Conclusions

Peginterferon and ribavirin therapy is effective for the retreatment of Korean chronic hepatitis C patients who have failed interferon/ribavirin, especially in patients with genotypes 2 and 3, relapse, an adherence to peginterferon over 80%, and an EVR. For genotype 1 patients, retreatment was effective in patients with an adherence to peginterferon over 80%.

Boceprevir with peginterferon alfa-2a-ribavirin is effective for previously treated chronic hepatitis C genotype 1 infection

BACKGROUND & AIMS

The addition of boceprevir to therapy with peginterferon alfa-2b and ribavirin results in significantly higher rates of sustained virologic response (SVR) in previously treated patients with chronic hepatitis C virus (HCV) genotype-1 infection, compared with peginterferon alfa-2b and ribavirin alone. We assessed SVR with boceprevir plus peginterferon alfa-2a-ribavirin (PEG2a/R) in patients with identical study entry criteria.

METHODS

In a double-blind, placebo-controlled trial, 201 patients with HCV genotype-1 who had relapsed or not responded to previous therapy were assigned to groups (1:2) and given a 4-week lead-in phase of PEG2a/R, followed by placebo plus PEG2a/R for 44 weeks (PEG2a/R) or boceprevir plus PEG2a/R for 44 weeks (BOC/PEG2a/R). The primary end point was SVR 24 weeks after therapy ended.

RESULTS

The addition of boceprevir after 4 weeks of lead-in therapy with PEG2a/R significantly increased the rate of SVR from 21% in the PEG2a/R group to 64% in the BOC/PEG2a/R group (P < .0001). Among patients with poor response to interferon therapy (<1-log(10) decline in HCV RNA at week 4), 39% in the BOC/PEG2a/R group had SVRs, compared with none of the patients in the PEG2a/R group. Among patients with good response to interferon (≥1-log(10) decline), 71% in the BOC/PEG2a/R group had SVRs, compared with 25% in the PEG2a/R group. A ≥1-log(10) decline in HCV RNA at treatment week 4 was the strongest independent predictor of SVR, exceeding that of IL-28B genotype. Among 8 patients who began the study with HCV amino acid variants associated with boceprevir resistance, 3 (38%) achieved SVRs. Fifty percent of patients in the BOC/PEG2a/R group developed anemia (hemoglobin <10.0 g/dL), compared with 27% in the PEG2a/R group; 43% vs 21%, respectively, developed neutropenia (neutrophil count <750/mm(3)).

CONCLUSIONS

The addition of boceprevir after 4 weeks of lead-in therapy with PEG2a/R caused significantly higher rates of SVR in previously treated patients with chronic HCV genotype-1 infection, compared with patients given only PEG2a/R. ClinicalTrials.gov Identifier: NCT00845065.

The effectiveness of retreatment with peginterferon alfa and ribavirin in patients with chronic viral hepatitis C genotype 2 and 3: a prospective cohort study in Brazil

Background

More than 50% of patients infected with chronic hepatitis C virus (HCV) do not respond to treatment with conventional interferon (IFN) combined with ribavirin (RBV). The aim of our study was to evaluate the effectiveness of retreatment with peginterferon alfa-2a or 2b (PEG-IFN 2a or 2b) concomitantly with RBV in patients with HCV genotype 2 and 3, which were non-responders or relapsers to initial treatment with IFN / RBV and to identify possible predictors of sustained virological response (SVR).

Methods

From September 2003 to March 2009 a cohort of 216 patients who had previously failed therapy with a regimen of standard interferon and ribavirin, were followed in a specialized service implemented in the Brazilian Unified Health System, Rio Grande do Sul. All patients were retreated with PEG-IFN 2a or 2b per week, associated with RBV, through oral route, with doses determined according to weight (1,000 mg if weight ≤ 75 Kg and 1,250 mg if ≥ 75 Kg) per day for 48 weeks. The HCV-RNA was tested by Polymerase Chain Reaction (PCR). Virological Response (VR) within 48 weeks and SVR in the 72 weeks was considered for evaluation of treatment efficacy. Analyses were performed in patients who received at least one dose of PEG-IFN.

Results

The SVR rate for non-responders to previous treatment was 34.4% and for relapsers was 50% (p = 0.031). As predictive factors that contribute to improve SVR, were identified the age (p = 0.005), to be relapsers to previous treatment (p = 0.023) and present liver biopsy examination Metavir F0-F2 (p = 0.004). In assessing the safety profile, 51 patients (23.6%) discontinued treatment prematurely.

Conclusions

This alternative retreatment for patients who have failed prior therapies for anti-HCV, has demonstrated promising SVR rate, provided that it includes a careful selection of patients with predictors of response and adverse events monitored.

Impact of ribavirin dose on retreatment of chronic hepatitis C patients

AIM: To study the efficacy and factors associated with a sustained virological response (SVR) in chronic hepatitis C (CHC) relapsing patients.

METHODS: Out of 1228 CHC patients treated with pegylated interferon (PEG-IFN) and ribavirin (RBV), 165 (13%) had a relapse. Among these, 62 patients were retreated with PEG-IFN-α2a or -α2b and RBV. Clinical, biological, virological and histological data were collected. Initial doses and treatment modifications were recorded. The efficacy of retreatment and predictive factors for SVR were analyzed.

RESULTS: An SVR was achieved in 42% of patients. SVR was higher in young (< 50 years) (61%) than old patients (27%) (P = 0.007), and in genotype 2 or 3 (57%) than in genotype 1 or 4 (28%) patients (P = 0.023). Prolonging therapy for at least 24 wk more than the previous course was associated with higher SVR rates (53% vs 28%, P = 0.04). Also, a better SVR rate was observed with RBV dose/body weight > 15.2 mg/kg per day (70% vs 35%, P = 0.04). In logistic regression, predictors of a response were age (P = 0.018), genotype (P = 0.048) and initial RBV dose/body weight (P = 0.022). None of the patients without a complete early virological response achieved an SVR (negative predictive value = 100%).

CONCLUSION: Retreatment with PEG-IFN/RBV is eff-ective in genotype 2 or 3 relapsers, especially in young patients. A high dose of RBV seems to be important for the retreatment response.

Retreatment of patients with chronic hepatitis C relapsers to a previous antiviral treatment

BACKGROUND

The efficacy of retreatment with pegylated interferon (PEG-IFN) plus ribavirin for patients relapsing after a previous treatment remains to be fully elucidated, although extended treatment seems to be the best option in such cases.

AIM

To evaluate the efficacy of two extended protocols in patients with genotypes 1 or 4, or those with genotypes 2 or 3.

METHODS

A total of 181 patients who had relapsed after a previous antiviral treatment with PEG-IFNα2a plus weight-based ribavirin were offered retreatment with the same dose of both PEG-IFN plus ribavirin, to be continued for 48 weeks in those with genotypes 2 or 3 (group 1), and for 72 weeks in those with genotypes 1 or 4 (group 2).

RESULTS

A total of 59 patients (32.5%) refused the retreatment, while 122 (78 men, 44 women) patients were enrolled in the study: 41 were allocated in group 1 and 81 in group 2. Cirrhosis at baseline (staging 5/6 according to Ishak's score was recorded in 11 patients, six in group 1 and five in group 2). Nine patients (7.3%) in group 2 discontinued the treatment (due to lack of response). The remaining patients completed the treatment and were followed-up for at least 12 months after the treatment. Sustained virological response (SVR) rate was 82.9% in group 1 and 50.6% in group 2.

CONCLUSION

Patients with chronic hepatitis C with 'easy genotypes' relapsers to a previous antiviral treatment have more than 80% probability of achieving a SVR with a 48-week retreatment. Patients with 'difficult genotypes' have more than 50% chance of a SVR after a 72-week extended treatment.

S-adenosyl-methionine and betaine improve early virological response in chronic hepatitis C patients with previous nonresponse

BACKGROUND/AIMS

Treatment of chronic hepatitis C (CHC) with pegylated interferon α (pegIFNα) and ribavirin results in a sustained response in approximately half of patients. Viral interference with IFNα signal transduction through the Jak-STAT pathway might be an important factor underlying treatment failure. S-adenosyl-L-methionine (SAMe) and betaine potentiate IFNα signaling in cultured cells that express hepatitis C virus (HCV) proteins, and enhance the inhibitory effect of IFNα on HCV replicons. We have performed a clinical study with the aim to evaluate efficacy and safety of the addition of SAMe and betaine to treatment of CHC with pegIFNα/ribavirin.

METHODS

In this open-label pilot study, 29 patients with CHC who failed previous therapy with (peg)IFNα/ribavirin were treated with SAMe, betaine, pegIFNα2b and ribavirin. Treatment duration was 6 or 12 months, depending on genotype, and the protocol comprised a stopping rule at week 12 if early virological response (EVR) was not achieved. Virological and biochemical response and safety were assessed throughout the treatment.

RESULTS

29 patients were enrolled and treated according to the study protocol. 79% of the patients were infected with genotype 1, 72% had advanced fibrosis, 76% had previously received pegIFNα/ribavirin, and only 14% achieved EVR to the previous treatment. When treated with the study medications, 17 patients (59%) showed an EVR, only 3 (10%) however achieved a sustained virological response (SVR). SAMe and betaine were found to be safe when used with pegIFNα/ribavirin.

CONCLUSION

The addition of SAMe and betaine to pegIFNα/ribavirin improves early virological response in CHC.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00310336.

Retreatment of hepatitis C patients with pegylated interferon combined with ribavirin in non-responders to interferon plus ribavirin. Is it different in real life?

BACKGROUND

More than 50% of hepatitis C viruses (HCV)-infected patients do not respond to the classical Interferon (IFN)/Ribavirin (RBV) combination therapy. The aim of this study was to evaluate the efficacy of retreatment with Peg-Interferon alpha-2b (PEG-IFN alpha-2b) plus RBV, in patients with HCV, genotypes 1 or 3, who were non-responders to the previous standard treatment with IFN/RBV.

METHODS

In the period 2005-2007, a total of 238 HCV chronic patients were non-responders to previous treatment with IFN plus RBV. Of these 130 agreed to be retreated with PEG-IFN alpha-2b and participated in this evaluation (90 with genotype 1 HCV and 40 with genotype 3 HCV). Patients were retreated at assisted IFN application hubs in compliance with the country's public health system rules. They received subcutaneous PEG-IFN alpha-2b, 1.5 microg, once weekly, associated with RBV, through the oral route, with doses determined according to weight (1,000 mg if weight <or= 75 kg and 1,250 mg if > 75 kg). Patients with genotype 1 HCV were retreated for over 48 weeks and patients with genotype 3 HCV for over 24 weeks. HCV-RNA was tested by polymerase chain reaction (PCR) at baseline, at week 12, at the end of the treatment, and 6 months thereafter. The predictiveness of week 12 in the development of a sustained virologic response (SVR) was also evaluated. Patients with negative HCV-RNA at week 12 were considered as early virologic responders (EVR).

RESULTS

EVR was observed in 25% of the patients with genotype 1 HCV and in 64% of the patients genotype 3 HCV (risk = 2.075 and p-value = 0.0414). SVR was observed in 22.2% of the patients with genotype 1 HCV and in 40% with genotype 3 HCV (intention-to-treat analysis). The positive predictive value (PPV) of the HCV-RNA testing at week 12, in order to obtain the SVR, was 65% for genotype 1 and 56% for genotype 3, and the negative predictive value (NPV) was 88% for genotype 1 and 89% for genotype 3.

CONCLUSIONS

PEG-IFN alpha-2b plus weight-based ribavirin is effective in re-treating previous interferon-alpha plus RBV failure; 22.2% of the patients with genotype 1 HCV and 40% of patients with genotype 3 HCV achieved SVR.

Management of chronic hepatitis C patients who have relapsed or not responded to pegylated interferon alfa plus ribavirin

Development of therapeutic strategies for patients with chronic hepatitis C who experience virological breakthrough, relapse or nonresponse lag behind those for treatment-naïve patients. The probability of a previously treated patient responding to re-treatment depends on the nature of the previous regimen, the magnitude of the response to previous treatment and the patient's characteristics. Relapsers have higher sustained virological response rates than nonresponders when re-treated with pegylated interferon plus ribavirin. Re-treatment of nonresponders to pegylated interferon plus ribavirin with the standard 48-week regimen resulted in an approximate 6% sustained response rate in the EPIC-3 program. In the REPEAT trial, the sustained response rate was significantly higher in nonresponders to pegylated interferon alfa-2b (12 kD) plus ribavirin randomized to 72 weeks of peginterferon alfa-2a (40 kD) plus ribavirin, compared with a 48-week regimen (16%vs 8%, P = 0.0006). Based on available data, extended treatment is the best option for these individuals. Undetectable viral RNA at week 12 is an important criterion for re-treatment in the REPEAT and EPIC studies. Maintenance therapy with pegylated interferon is generally ineffective in nonresponders and cannot be recommended. Directly acting antivirals may increase response rates and the burden of adverse events when combined with the standard of care, but will not be available for some years. In conclusion, after careful evaluation of an individual's benefit-risk ratio, a 72-week regimen is the preferred strategy for optimizing sustained response rates in patients who have not responded to the standard of care, provided that viral RNA is undetectable at week 12 of re-treatment.

Retreatment with pegylated interferon plus ribavirin of chronic hepatitis C non-responders to interferon plus ribavirin: a meta-analysis

BACKGROUND/AIMS

Efficacy of retreatment with pegylated interferon (PEG-IFN) plus ribavirin of non-responders to standard or pegylated IFN plus ribavirin has been assessed in various studies, but sustained virologic response (SVR) rates are variable and factors influencing efficacy and tolerability still remain incompletely defined. We aimed to focus on SVR rates and to identify factors influencing them in this meta-analysis.

METHODS

MEDLINE as well as a manual search were used. Studies were included if they were controlled or uncontrolled trials, if they had been published as full-length papers and if they included non-responders to standard or pegylated IFN and ribavirin therapy. Fourteen trials were included in the meta-analysis. Data on study populations, interventions, and outcomes were extracted from trials using a random-effects model. Primary outcome was the SVR rate.

RESULTS

The pooled estimate of SVR rate was 16.3% (95% Confidence Interval - 95% CI, 8.3-29.6%). There was a significant heterogeneity among studies (p<0.0001). Heterogeneity was less apparent in studies that included fewer patients with cirrhosis or overweight. By meta-regression, higher SVR rate was observed in trials with a lower prevalence of subjects with genotype 1 infection and with fewer overweight patients. The use of a 24-week retreatment stopping rule did not affect SVR rate.

CONCLUSIONS

The overall modest efficacy argues against an indiscriminate retreatment with PEG-IFN and ribavirin of all non-responders. Restricting retreatment to non-overweight patients or to those with genotype 2 or 3 infection, using a 24-week retreatment stopping rule, would optimize the potential benefit with a scarce likelihood of missing a curative response.

Treatment outcomes with pegylated interferon and ribavirin for male prisoners with chronic hepatitis C

GOALS

To report our experience with pegylated interferon and ribavirin treatment of hepatitis C virus (HCV) RNA-positive inmates at the Rhode Island Department of Corrections.

BACKGROUND

An estimated 1 out of 3 HCV-infected individuals will spend time in a jail or prison within a 1-year period, making prisons a unique setting for management of chronic HCV.

STUDY

Chart review of all inmates identified as having initiated HCV treatment between October 2000 and April 2004. HCV-infected individuals were identified by HCV antibody screening at intake for known risk factors, elevated aminotransferase levels, or per individual request. Treatment followed standard guidelines with weight-based dosing of pegylated interferon-alpha2b and ribavirin. End points were completion of therapy plus 6 months for sustained virologic response (SVR), therapy discontinuation, and loss to follow-up.

RESULTS

The cohort included 71 male patients, was mostly white (80%), and genotype 1 (65%). All 9 African Americans (AA) had genotype 1. Of 59 patients having liver biopsy, 41 had early stage disease. Overall SVR was 28%. Response rate was lower for genotype 1 compared with genotypes 2 and 3 (SVR 18% vs. 60% and 50%). Of inmates with genotype 1, no difference existed in treatment response by race (SVR 22% AA vs. 18% white). Thirty-three patients completed treatment, 26 stopped for side effects, and 5 for initial nonresponse. Eleven were lost to follow-up.

CONCLUSIONS

Acceptable HCV treatment outcomes can be achieved in prisons. Our small study indicates no difference in treatment response by AA versus white race for genotype 1.

Peginterferon alfa-2b and ribavirin: effective in patients with hepatitis C who failed interferon alfa/ribavirin therapy

BACKGROUND & AIMS

Treatment with peginterferon alfa and ribavirin produces a sustained virologic response (SVR) in approximately 60% of hepatitis C virus (HCV)-infected patients. Alternate options are needed for patients who relapse or do not respond to therapy.

METHODS

This prospective, international, multicenter, open-label study evaluated efficacy and safety of peginterferon alfa-2b (1.5 microg/kg/wk) plus weight-based ribavirin (800-1400 mg/day) in 2333 chronic HCV-infected patients with significant fibrosis/cirrhosis whose previous interferon alfa/ribavirin therapy failed. Patients with undetectable HCV-RNA at treatment week (TW) 12 received 48 weeks of therapy; patients with detectable HCV-RNA at TW12 could enter maintenance studies at TW18; 188 patients with low/detectable HCV-RNA at TW12 continued therapy at the investigator's request.

RESULTS

Overall, 22% of the patients attained SVR (56% with undetectable HCV-RNA and 12% with low/detectable HCV-RNA at TW12). SVR was better in relapsers (38%) than nonresponders (14%), regardless of previous treatment, and in patients previously treated with interferon-alfa/ribavirin (25%) than peginterferon alfa-ribavirin (17%). Predictors of response in patients with undetectable HCV-RNA at TW12 were genotype (2/3 vs 1, respectively; odds ratio [OR] 2.4; P < .0001), fibrosis score (F2 vs F4; OR, 2.2; F3 vs F4; OR, 1.7; P < .0001), and baseline viral load (< or =600,000 vs >600,000 IU/mL; OR, 1.4; P = .0223). These factors plus previous treatment and response were overall predictors of SVR. Safety was similar among fibrosis groups.

CONCLUSIONS

Peginterferon alfa-2b plus weight-based ribavirin is effective and safe in patients who failed interferon alfa/ribavirin therapy. Genotype, baseline viral load, and fibrosis stage were predictors of response.

Expert opinion on the treatment of patients with chronic hepatitis C

The current preferred treatment for patients with hepatitis C virus (HCV) is combination therapy consisting of pegylated interferon alfa and ribavirin (RBV) for 24-48 weeks. Although this approach appears to be highly effective for patients with HCV genotypes 2 or 3, who have a sustained virological response (SVR) of approximately 80%, the treatment algorithm is less effective for patients with HCV genotype 1, as these patients have SVR rates of just 40-50%. In order to improve treatment outcomes, this article explores potential approaches for the optimization of treatment for patients with HCV genotype 1: considering shorter treatment periods for patients with a rapid virological response (RVR), increasing treatment periods for slow responders, and increasing RBV dose are all suggestions. Results from clinical trials suggest that approximately 20% of the HCV genotype 1-infected population are slow responders, and around 15% of all HCV genotype-1 infected patients could benefit from a shorter treatment duration without compromising the SVR rate. Interest has also focused on whether treatment duration could be individualized in some patients with genotype 2 and 3 infection. Here all the findings from recent studies are translated into practical advice, to help practitioners make evidence-based treatment decisions in everyday clinical practice. Although there are areas where currently available data do not provide conclusive evidence to suggest amending treatment approaches, there is clearly potential for individualized treatment in all aspects of hepatitis treatment in the future.

Peginterferon-α2a in the treatment of chronic hepatitis C

Chronic hepatitis C virus infection occurs worldwide and affects over 2.7 million adults in North America. Current standard of care is the combination of pegylated (peg) interferon and ribavirin for 24 weeks in hepatitis C virus genotypes 2 or 3 and at least 48 weeks in chronic hepatitis C virus infection genotypes 1 or 4. Peginterferon-α2a is a 40-kDa linear pegylated molecule that alters the pharmacokinetic properties of unmodified interferon-α. In clinical trials evaluating the combination of peginterferon-α2a and ribavirin in chronic chronic hepatitis C virus infection, sustained virologic response rates have been achieved in 46–52% of patients with genotype 1 and 76–80% of patients with genotypes 2 or 3. Studies on the role of longer treatment duration and retreatment in prior nonresponders are in progress. The main toxicities of peginterferon-α2a are flu-like symptoms and neuropsychiatric disorders, especially depression and cytopenias, and are found in similar rates to those observed with regular inteferon. Future areas of study include the role of peginterferon-α2a in combination with the newer oral chronic hepatitis C virus infection active agents in development.