Open, randomized, multicentre italian trial on PEG-IFN plus ribavirin versus PEG-IFN monotherapy for chronic hepatitis C in HIV-coinfected patients on HAART

BACKGROUND: Chronic hepatitis C is common and aggressive in HIV-positive patients, so the development of a well-tolerated HCV therapy is a priority. We evaluated the efficacy and safety of pegylated interferon alpha2b (PEG-IFN) plus ribavirin (RBV) versus PEG-IFN monotherapy in HIV/HCV-coinfected patients undergoing highly active antiretroviral therapy (HAART), and analysed the predictive factors of response. METHODS: An Italian, multicentre, open-label trial including 135 coinfected patients, randomized to PEG-IFN 1.5 microg/kg/week plus RBV 400 mg twice daily (n=69, arm A) or PEG-IFN 1.5 microg/kg/week (n=66, arm B) for 48 weeks. We assessed the predictive values of early virological response (EVR) at week 8 (HCV-RNA drop >2 log10 compared with baseline or undetectable levels) on sustained virological response (SVR). RESULTS: Fifty-five patients (28 from arm A and 27 from arm B) completed 48 weeks of therapy. At the end of treatment, 20/28 patients in arm A and 11/27 in arm B had HCV-RNA <50 IU/ml. In a per-protocol analysis, SVR was reached by 54% of patients in arm A (genotype 2-3, 11/16; genotype 1-4, 4/12) and 22% in arm B (genotype 2-3, 3/15; genotype 1-4, 3/12). In an intention-to-treat analysis, the SVR was 22% in arm A (genotype 2-3, 11/32; genotype 1-4, 4/37) versus 9% in arm B (genotype 2-3, 3/32; genotype 1-4, 3/34). The best predictors of SVR were the use of combination therapy, infection with HCV genotype 3 versus genotype 1, and EVR at week 8. Thirty patients (15 from arm A and 15 from arm B) dropped out of the trial prematurely due to side effects. The positive predictive value of EVR at week 8 was 65%, the negative predictive value was 86%. CONCLUSIONS: PEG-IFN plus RBV can be considered a solid option for the treatment of HIV/HCV-coinfected patients. The key to successfully improving efficacy is strong compliance through strict overall patient monitoring, in order to best manage drug toxicity. EVR assessment at week 8 may become a useful stategy in the management of therapy.     

Hepatitis C virus-RNA clearance in HIV-coinfected patients with chronic hepatitis C treated with pegylated interferon plus ribavirin

Hepatitis C virus (HCV)-RNA clearance seems to occur more slowly in HIV/HCV-coinfected patients than in HCV-monoinfected subjects treated with pegylated interferon alpha (peg-IFN) plus ribavirin (RBV). As a consequence, concern has arisen over the feasibility of following the treatment rules applied to HIV-negative patients with chronic hepatitis C. A total of 89 HIV/HCV-coinfected patients who had fully completed a course of peg-IFN plus RBV were analysed. Of these, 29 (32.6%) reached sustained virological response (SVR). Reductions >2 logs in plasma HCV-RNA occurred in 52 (58%) patients at week 12 of treatment (early virological response; EVR). None of patients who showed HCV-RNA drops <2 logs at week 12 reached SVR (negative predictive value: 100%). The positive predictive value of EVR was 56%. On the other hand, relapses occurred in 19 (39.6%) out of the 48 patients who had negative HCV-RNA at the end of treatment, and there were no differences noted when comparing patients with HCV genotypes 2/3 and 1/4. In summary, the quantitative assessment of plasma HCV-RNA at week 12 predicts the chance of SVR using peg-IFN plus RBV in HIV-positive patients with chronic hepatitis C, as it does in HIV-negative individuals. Thus, discontinuation of anti-HCV therapy, which is associated with frequent side effects, might be warranted in HIV/HCV-coinfected patients showing HCV-RNA reductions <2 logs at week 12 of treatment. On the other hand, relapses in virological responders were unexpectedly high in HIV/HCV-coinfected patients when treatment was provided following the rules applied to HIV-negative subjects. This is particularly relevant for HCV genotypes 2/3, which only rarely relapse in HIV-negative patients. Therefore, extending therapy (for 12 months in HCV genotypes 2/3 and perhaps for 18 months in HCV genotypes 1/4) might be warranted in HIV/HCV-coinfected patients showing EVR.     

Long-term follow-up of HIV-infected patients with chronic hepatitis C virus infection treated with interferon-based therapies

BACKGROUND: Chronic hepatitis C virus (HCV) infection is frequent among HIV-infected patients. Clearance of serum HCV RNA 6 months after discontinuing HCV therapy is generally interpreted as a cure of HCV infection in HIV-negative subjects. However, the occurrence of liver complications (including hepatocellular carcinoma) and/or HCV relapses in coinfected patients when followed for long periods of time after HCV therapy is not well known. METHODS: All HIV-infected patients who had been treated for chronic hepatitis C at our institution and had a minimum follow-up of 6 months after discontinuing therapy were retrospectively analysed. They had received one of three HCV treatment modalities: IFN monotherapy, IFN plus ribavirin (RBV) or pegylated interferon (PEG-IFN) plus RBV. RESULTS: A total of 351 patients were retrospectively analysed. Sustained virological response (SVR) to HCV therapy had been reached by 77 (22%) of them: 22/119 (18.5%) with IFN monotherapy, 17/106 (16%) with IFN plus RBV and 38/126 (30.2%) with PEG-IFN plus RBV. Considering the HCV genotypes, SVR had been reached by 19/184 (10.3%) of patients with genotype 1, 54/138 (39.1%) with genotypes 2 or 3, and 4/29 (13.8%) of those with genotype 4. Within a total of 4466 patient-months follow-up (mean of 58 months), none of the 77 patients with SVR showed HCV-RNA rebounds, elevations in liver enzymes potentially linked to HCV, development of hepatocellular carcinoma or episodes of decompensated cirrhosis. In contrast, all 274 patients who did not reach SVR with HCV therapy showed evidence of persistent serum HCV RNA and 90% of them showed liver enzyme elevations during a total of 15344 patient-months follow-up (mean of 56 months). Moreover, 11 (4%) developed clinical complications of liver cirrhosis and two of them died of end-stage liver disease. CONCLUSIONS: HCV replication and HCV-related liver disease seem to be permanently halted in HIV/HCV-coinfected patients showing HCV-RNA clearance 6 months after completing any kind of IFN-based therapy. In contrast, complications of liver disease due to persistent HCV infection continue to occur in non-responders. The role of maintenance HCV therapy should be explored in HIV/HCV-coinfected patients.     

Impact of ribavirin exposure on early virological response to hepatitis C therapy in HIV-infected patients with chronic hepatitis C

BACKGROUND: The use of pegylated interferon (PEG-IFN) plus ribavirin (RBV) is currently the recommended treatment for chronic hepatitis C virus (HCV) infection. Coinfection with HIV is a negative predictor of response, for reasons not well understood. METHODS: We examined the virological response at weeks 4 and 12 in 198 HCV/HIV-coinfected patients enrolled in a prospective trial in which PEG-IFN alpha 2a (180 microg per week) and RBV (1000-1200 mg daily) were provided. RESULTS: In an on-treatment analysis, 52.8% of patients achieved undetectable HCV-RNA (<600 IU/ml) at week 4, while 63% and 77.2% of patients had a decline of at least 2 and 1 log10, respectively. At week 12, 73.1% of patients reached undetectable HCV-RNA, and 83.5% and 89% achieved at least a 2- and 1-log10 drop, respectively. More than 85% of HCV genotypes 2/3 cleared HCV-RNA at week 4, a proportion significantly higher when compared with genotypes 1 (33.8%) and 4 (28.6%). Multivariate logistic regression analysis identified genotype 3 and RBV exposure (mg/kg of body weight) as independent predictors of virological response at week 12 of therapy. CONCLUSION: Early virological response rates to PEG-IFN plus RBV in HCV/HIV-coinfected patients seem to be similar to those reported for HCV-monoinfected subjects. The use of suboptimal doses of RBV in most earlier trials might account for the low response rates seen in coinfected patients. To our knowledge, this is the first report demonstrating that RBV exerts a significant independent effect on early virological response. Therefore, strategies aimed at optimizing doses and adherence to RBV might help to improve responses to HCV therapy in coinfected patients.     

An inadequate dose of ribavirin is related to virological relapse by chronic hepatitis C patients treated with pegylated interferon alpha-2b and ribavirin

The aim of this large-scale analysis was to assess the effect of 48-week pegylated interferon (PEG-IFN) α-2b and ribavirin (RBV) therapy on virological relapse by patients infected with hepatitis C virus (HCV) genotype 1. The relationship between virological relapse and the dose of PEG-IFNα-2b and RBV was investigated in 619 patients who had once cleared HCV RNA during PEG-IFNα-2b and RBV treatment for 48 weeks. The overall virological relapse rate was 34.1% (211 of 619). The relapse rate was 59.5% (22 of 37) for patients who received <6 mg/kg/day of RBV, even if a sufficient dose of PEG-IFNα-2b (≥1.5 μg/kg/day) was received. In contrast, the relapse rate was 28.1% (16 of 57) for patients who received ≥12 mg/kg/day of RBV, irrespective of the PEG-IFNα-2b dose. The relapse rates were significantly increased with the reduction of the RBV dose for both PEG-IFNα-2b doses of ≥1.2 and <1.2 μg/kg/week (P < 0.0001 and P = 0.0006, respectively). Moreover, the relapse rate was 41.2% (35 of 85) for patients with an early virological response (EVR) who received <6 mg/kg/day of RBV. The relapse rates were significantly increased with the reduction of the RBV dose in both those patients with an EVR and those with a late virological response (P = 0.0006 and P = 0.0088, respectively). To summarize, for HCV genotype 1 patients treated with PEG-IFNα-2b and RBV, the virological relapse of HCV was RBV dose-dependent, irrespective of the dose of PEG-IFNα or the effect of early viral kinetics.     

Sustained negativity for HCV-RNA over 24 or more months by long-term interferon therapy correlates with eradication of HCV in patients with hepatitis C virus genotype 1b and high viral load

OBJECTIVE: We assessed whether sustained negativity for HCV-RNA over 24 or more months by long-term interferon (IFN) therapy correlates with eradication of HCV in patients with hepatitis C virus genotype 1b and high viral load or not. METHODS: The number of patients with HCV-genotype 1b and high viral load exceeding 1 Meq/ml who received 6 MU of natural IFN-alpha daily for 2-8 weeks, followed by three times/week for 16-22 weeks and negativity for HCV-RNA during IFN administration was 403. Forty-one of 403 patients received 6 MU of natural IFN-alpha three times/week for more than 18 months after the initial IFN therapy (long-term-IFN-group). Three hundred and two patients did not receive any IFN treatment for 6 months after the termination of the 6-month course (6-month-IFN-group). Sustained virological response (SVR) was defined as negative HCV-RNA at both 3 and 6 months after the completion of IFN therapy. RESULTS: SVR was noted in 73.2% (30/41) of long-term-IFN-group and 18.2% (55/302) of 6-month-IFN-group. Multivariate analysis showed that long-term IFN therapy was the most significant contributor to SVR (p < 0.0001). CONCLUSION: Sustained negativity of HCV-RNA for 24 or more months by long-term IFN therapy correlated with SVR in patients with genotype 1b and high viral load.     

Response to interferon-based therapies in HIV-infected patients with chronic hepatitis C due to genotype 4

BACKGROUND: The hepatitis C virus (HCV) genotype is the main predictor of response to interferon (IFN)-based therapies. HCV genotype 4 is spreading among European intravenous drug users, who are frequently coinfected with HIV. Information about treatment response in this subset of patients is scarce and conflicting results have been reported. METHODS: All HIV-infected patients treated for chronic hepatitis C at our institution with a minimum follow-up of 6 months after discontinuing therapy were retrospectively analysed. They had received one of three HCV treatment modalities: IFN monotherapy, IFN plus ribavirin (RBV) or pegylated interferon (PEG-IFN) plus RBV. Treatment responses were stratified according to HCV genotype. RESULTS: A total of 390 patients were analysed. Sustained virological response (SVR) to HCV therapy had been reached by 90 (23.1%): 22/119 (18.5%) with IFN monotherapy; 17/106 (16%) with IFN plus RBV; and 51/165 (30.9%) with PEG-IFN plus RBV. SVR was significantly higher among those with HCV genotypes 2 or 3 (40.4%; 61/151) than in patients with either HCV genotype 1 (11.2%; 22/197) or HCV genotype 4 (16.7%; 7/42) (P<0.0001). In contrast, there were no significant differences in the response rate comparing HCV genotypes 1 and 4 (P=0.53). CONCLUSIONS: Response to IFN-based therapies in HIV-positive patients with hepatitis C due to HCV genotype 4 is poor, similar to that obtained for HCV genotype 1 and much lower than for HCV genotypes 2 and 3. Therefore, HIV-infected patients with hepatitis C due to genotype 4 should be considered as a particular subset of difficult-to-treat patients. New treatment strategies and drugs for these patients are eagerly awaited.     

Usefulness of a new immunoradiometric assay of HCV core antigen to predict virological response during PEG-IFN/RBV combination therapy for chronic hepatitis with high viral load of serum HCV RNA genotype 1b

We investigated the clinical usefulness of a new immunoradiometric (IRM) assay of hepatitis C virus (HCV) core antigen in predicting virological response during pegylated interferon plus ribavirin (PEG-IFN/RBV) combination therapy for chronic hepatitis with high viral loads of serum HCV RNA genotype 1b. Thirty-nine patients received a regimen of PEG-IFNalpha-2b (1.5 microg/kg/week s.c.) in combination with RBV (600-1,000 mg/day). Of the 39 patients, 18 (46.2%) achieved sustained virological response (SVR), 11 (28.2%) attained partial response (PR) and 10 (25.6%) showed no response (NR). Four weeks after the start of therapy, 1- and 2-log reductions in the amount of HCV core antigen were observed in 20 (2/10) and 0% (0/10) showing NR, 91 (10/11) and 63.6% (7/11) with PRs, and 88.9 (16/18) and 55.6% (10/18) of patients with SVR, respectively. The 1- and 2-log reductions 4 weeks after the start of therapy were not a defining condition for PR and SVR. The amount of HCV core antigen was significantly different between SVR and PR patients on days 1 and 7, and between patients with NR and SVR at all points of time. In conclusion, this new IRM assay is useful in predicting virological response during PEG-IFN/RBV therapy.     

Prolonged negative HCV-RNA status led to a good outcome in chronic hepatitis C patients with genotype 1b and super-high viral load

OBJECTIVE: We examined whether a sustained negative HCV-RNA status for 48 weeks affects the outcome in patients with genotype 1b and super-high viral load, and also investigated whether the outcome is affected by the induction therapy of twice-daily pre-administrated interferon (IFN)-beta. METHODS: 78 eligible patients were divided into four groups. 40 were patients assigned to the short treatment protocol. 13 patients received 3 MU IFN-beta twice daily for 2 weeks followed by IFN-alpha2b+ribavirin for 22 weeks (beta-induction group: group 1). 27 patients received IFN-alpha2b+ribavirin for 24 weeks (standard combination group: group 2). 38 patients were assigned to the maintenance treatment protocol. All of the 13 in the beta-induction group (group 3) and 21 of 25 patients in the standard combination group (group 4) who were negative HCV-RNA PCR at week 24 had IFN monotherapy to maintain a negative HCV-RNA result for 48 weeks. RESULTS: An HCV-RNA-negative status at week 24 was observed in 96% (25/26) of groups 1 and 3 versus in 79% (41/52) of groups 2 and 4 (p<0.01). The sustained virological response (SVR) was 38% (5/13) in group 1 and 11% (3/27) in group 2 (p<0.05). In the maintenance treatment, SVR was observed in 46% (6/13) of group 3 and 32% (8/25) of group 4 (NS). CONCLUSIONS: A sustained negative HCV-RNA status for 48 weeks might be associated with viral elimination in patients with genotype 1 and super-high viral load.     

Rapid virological response at week 4 predicts response to pegylated interferon plus ribavirin among HIV/HCV-coinfected patients

INTRODUCTION: The clinical applicability of early viral kinetics at week 4 in predicting sustained virological response (SVR) of pegylated interferon (peg-IFN) plus ribavirin (RBV) in HIV/HCV-coinfected patients is unclear. Our objective was to determine if rapid virological response (RVR) at week 4 of therapy with peg-IFN and RBV could predict SVR among HIV/HCV-coinfected patients. METHODS: HIV/HCV-coinfected patients in whom an HCV viral load determination had been carried out at week 4 of therapy were included in the study. The positive predictive value (PPV) and the negative predictive value (NPV) of RVR (undetectable serum HCV RNA at 4 week) for SVR were calculated in the study population. Receiver operating characteristic curves were calculated to determine the best cutoff of HCV RNA decrease to predict treatment failure. RESULTS: A total of 101 HIV/HCV-coinfected patients were included. RVR and SVR were observed in 39 (39%) and in 49 (48%) individuals, respectively. Of patients with RVR, 37/39 patients achieved SVR (PPV: 95%), whereas 50/62 individuals without RVR did not show SVR (NPV: 81%). The highest NPV (96%) was reached by using a cutoff level of HCV RNA decrease of 0.6 log10. By applying this cutoff level, treatment could have been discontinued in 25 (25%) patients. CONCLUSIONS: An undetectable serum HCV RNA determination at week 4 of treatment with peg-IFN plus RBV is a reliable predictor of SVR in HIV/HCV-coinfected patients. In addition, a decrease of HCV RNA less than 0.6 log10 at this point of treatment could identify an appreciable proportion of individuals who will fail to achieve SVR.     

Role of viral kinetics under HCV therapy in HIV/HCV-coinfected patients

Patients coinfected with hepatitis C virus (HCV) and human immunodeficiency virus (HIV) are less responsive to anti-HCV therapies and are at a higher risk of toxicity than HCV monoinfected patients. HCV viral kinetics is the basis for the study of response to interferon-based therapy and for predicting sustained virological response (SVR). A lack of early virological response (EVR; undetectable HCV RNA or a decrease of >/=2 log(10) from baseline) after 12 weeks of pegylated interferon (peg-IFN) plus ribavirin (RBV) is an equally reliable predictor of lack of SVR in HIV/HCV-coinfected patients and in the monoinfected HCV population. Early stopping rules are particularly important in coinfected HIV/HCV patients, considering their low chances of response in the more difficult-to-treat HCV genotypes 1 and 4 (<30%). Several factors have been involved in this low efficacy, including higher baseline HCV viraemia, slower viral kinetics decay under interferon pressure and a defective immune substratum. A better understanding of HCV viral kinetics under HCV therapy may be the basis for assaying different peg-IFN plus RBV schedules, such as induction or extending strategies, and may help physicians to make tailored decisions for the management of their patients.     

2'-,5'-Oligoadenylate synthetase response ratio predicting virological response to PEG-interferon-alpha2b plus ribavirin therapy in patients with chronic hepatitis C

OBJECTIVE: Although all the mechanisms of elimination of hepatitis C virus (HCV) by Interferon (IFN) have not been fully elucidated, the 2'-5'-oligoadenylate (2-5A) system is one of the mechanisms of the antiviral effect of IFN. Consequently, the measurement of 2'-5'-oligoadenylate synthetase (2-5AS) activity could be useful for the evaluation of IFN treatment. This retrospective study was aimed at assessing whether 2-5AS activity functions as a clinical marker of virological response to PEG-interferon-alpha2b (PEG-IFN) plus ribavirin therapy of chronic hepatitis C. METHODS: The 32 patients included in this study had high viral loads of serum HCV-RNA of genotype 1b with chronic hepatitis C. All the patients received a regimen of PEG-IFN plus ribavirin for 48 weeks, and were then divided into two groups: one group (effective group) with undetectable serum HCV-RNA levels at 24 weeks (n = 22) of therapy, the other group (ineffective group) with persistent presence of HCV-RNA in serum at 24 weeks (n = 10). The 2-5AS activity in serum was measured 2, 8 and 12 weeks before initial administration. RESULTS: The 2-5AS response ratio (measured value/measured value of baseline 2-5AS) at 2, 8 and 12 weeks after the administration in the effective group was significantly higher than that in the ineffective group. CONCLUSIONS: These results suggest that the ratio of 2-5AS is closely related to the antiviral effect, and that the measurement of 2-5AS response ratio may be a useful clinical parameter of virological response to PEG-IFN plus ribavirin therapy of chronic hepatitis C.     

Treatment of chronic hepatitis C in southern Taiwan

Chronic hepatitis C virus (HCV) infection may lead to cirrhosis and hepatocellular carcinoma. Interferon (IFN)-alpha is effective in the treatment of chronic hepatitis C. The rate of response to IFN is enhanced by increasing the IFN dose. Extending the treatment duration can reduce the relapse rate. Addition of ribavirin to IFN increases the sustained virological response (SVR). Thus, combination therapy with IFN and ribavirin was adopted for the treatment of chronic hepatitis C in Kaohsiung Medical University Hospital in 1998. Approximately 60% of patients receiving IFN/ribavirin therapy gained SVR. IFN 6 million units three times per week combined with daily ribavirin for 6 months achieved SVR more frequently than combination therapy with 3 million units. Factors for SVR in these combination regimens were HCV genotype, viral load and early virological response. Long-term follow-up of patients treated with IFN has shown that SVR might reduce the risk of progression to cirrhosis and hepatocellular carcinoma. Pegylated (peg)-IFN has a longer half-life and better efficacy. Combination therapy with peg-IFN and ribavirin accomplished higher SVR than conventional IFN and ribavirin. A multicenter clinical trial was conducted in Taiwan to compare the efficacy of combination therapy between peg-IFN/ribavirin and conventional IFN/ribavirin for 6 months. SVR was higher in patients receiving peg-IFN and ribavirin, especially in those infected with HCV genotype 1b. Based on the results obtained, the national health insurance started to sponsor the combination therapy in October 2003, with a suggested duration for 6 months. Some small-scale studies in Taiwan have postulated higher SVR for treatment duration of 12 than of 6 months in patients with genotype 1b. Further investigation should be conducted in the near future.     

Therapy for treatment-refractory chronic hepatitis C virus genotype 1b infection: A retrospective analysis

Background:

The most effective current therapy for hepatitis C virus (HCV) infection is the combination of pegylated interferon (peg-IFN) plus ribavirin (RBV).

Objective:

The aim of this retrospective analysis was to determine the rateof response to this therapy, and the factors affecting outcome, in patients with treatment-refractory chronic HCV genotype l b.

Methods:

The records of patients with chronic HCV infection and HCV geno-type1b who failed (nonresponse or relapse) previous treatment with standard interferon (IFN) + RSV were retrospectively analyzed for demographic data, virologic load, liver histology, biochemistry, treatment-related adverse effects (AEs), and the effects of dose reduction during treatment with peg-IFN + RBV for 48 weeks. Early virologic response (EVR) was defined as ≥2-log (copies/mL) decrease from baseline in serum HCV RNA concentration or the absence of detectable serum HCV RNA at treatment week 12. End-of-treatment response (ETR) was defined as the absence of detectable serum HCV RNA at treatment week 48. Sustained virologic response (SVR) was defined as the absence of detectable serum HCV RNA 24 weeks after treatment was discontinued. Factors affecting treatment outcome were determined using correlation analyses.

Results:

Data from the files of 17 patients (12 men, 5 women; mean [SD] age, 48 [2] years) were analyzed. EVR was achieved in 7 patients; however, viral breakthrough occurred in 2 of these patients during the treatment period, and 5 of these patients discontinued treatment because of severe treatment-related AEs (depression [1 patient] and neutropenia [4]). Seven patients achieved ETR, but HCV infection relapsed during the follow-up period. Three (18%) patients achieved SVR. Data concerning previous patterns of response to IFN + RBV therapy were available in 10 patients. Of these, 3 of 6 patients who had experienced relapse with the previous treatment achieved SVR with peg-IFN + RBV; neither of the 2 patients with nonresponse to the previous treatment achieved SVR. Major determinants of failure to reach SVR in these patients included previous nonresponder pattern, noncompliance with the therapy, and advanced-stage liver fibrosis. Tolerability was similar to that with the previous treatment.

Conclusions:

In this study in patients with chronic HCV genotype lb infectionand a history of relapse or nonresponse to standard IFN + RSV treatment, treatment with peg-IFN + RBV achieved an SVR rate of 18%. Further research is needed to determine the role of peg-IFN + RBV in the re-treatment of HCV infection.     

Optimizing outcomes in patients with hepatitis C virus genotype 1 or 4

Currently, many decisions for the treatment of hepatitis C virus (HCV) are based on genotype, which is the most significant baseline predictor of response to therapy; however, it has become increasingly apparent that fixed treatment durations might not be appropriate for all patients. The use of on-treatment predictors such as rapid virological response (RVR) at week 4 and early virological response (EVR) at week 12 can be used to predict the likelihood of achieving a sustained virological response (SVR), helping to tailor treatment to the individual. Until now, EVR has been defined as achieving either undetectable HCV RNA (< 50 IU/ml) or a > 2 log drop in HCV RNA, but still detectable, at week 12. However, rates of SVR in patients achieving an EVR are heterogeneous. It has recently been suggested that by subdividing EVR into RVR (< 50 IU/ml at week 4), complete EVR (HCV RNA < 50 IU/ml at week 12) or partial EVR (HCV RNA > 2 log drop in HCV RNA but still detectable [> 50 IU/ml] at week 12), it might be possible to further improve the prediction of patients likely to achieve an SVR and may allow for tailoring of treatment duration. Genotype 1 and 4 patients achieving an RVR have high rates of SVR and may be candidates for shorter treatment duration. Patients with a complete EVR achieve high SVR rates with the current treatment duration of 48 weeks, whereas patients achieving a partial EVR have lower rates of SVR and could benefit from treatment intensification to 72 weeks. Here, we discuss the importance of baseline predictors of response and the emerging concept of response-guided therapy in genotype 1 and 4 patients.     

Impaired response to interferon-alpha2b plus ribavirin in cirrhotic patients with genotype 3a hepatitis C virus infection

Patients with chronic infection with the 3a genotype of hepatitis C virus (HCV) are considered as 'easy-to-treat' with interferon/ribavirin (IFN/RBV), independent of liver disease severity. However, patients with extensive fibrosis or cirrhosis were under-represented in all the registration Phase III trials performed so far. To assess the influence of liver fibrosis on the outcome of anti-HCV therapy, all patients with genotype 3a hepatitis C who were naive to IFN-based therapies, and received RBV combined with standard IFN or pegylated IFN-(alpha2b (peg-IFN-alpha2b) as standard of care for their disease, were investigated at our centre. A sustained virological response (SVR) was achieved in 68 of 91 patients (75%) independent of IFN type, pretreatment viraemia, clearance of HCV RNA at week 4 and relevant co-morbidities. A SVR was less common in cirrhotics (6 of 17) than in non-cirrhotics (62 of 74; 35% vs 84%; P<0.0005). Compared to non-cirrhotics, the age and sex adjusted odds ratio (OR) of treatment failure for cirrhotics was 10.1 (95% confidence interval: 2.4-41.7). By multivariate analysis, cirrhosis was the only predictor of non-SVR. In conclusion, cirrhosis is an independent predictor of IFN/RBV treatment failure in patients chronically infected with HCV 3a and is associated with an increased risk of post-treatment hepatitis relapse. Evaluation of liver fibrosis is important in the management of patients with genotype 3a hepatitis C, since it helps to predict response to IFN/RBV therapy.     

Prediction of treatment outcome in chronic hepatitis C patients based on early viral dynamics during high-dose induction interferon and ribavirin therapy

OBJECTIVE: In chronic hepatitis C, early viral load decline after interferon administration is dose dependent and reflects the intrinsic viral susceptibility to the antiviral action of interferon. We examined whether the augmented suppression of susceptible viral loads by high-dose induction interferon could possibly discriminate responsive patients from non-responsive patients at an early stage of treatment. METHODS: Fifty-nine chronic hepatitis C patients were randomly allocated to receive one of two treatment regimens; 3 MU interferon three times weekly plus ribavirin 1,000 mg/day for 24 weeks in the CR group (n = 30), and the same regimen as in the CR group except 10 MU interferon daily for the first week in the HR group (n = 29). Changes in viral loads during the first week of treatment were analyzed in terms of sustained virological response (SVR). RESULTS: The positive predictive values of undetectable (<100 IU/ml) or low serum HCV RNA (<2,000 IU/ml) after 1 week of treatment for SVR were 100% in both treatment groups, whereas the negative predictive values of the low viral titer were 91% in the HR group and 70% in the CR group. CONCLUSION: One-week virological response to high-dose induction interferon/ribavirin combination therapy is more predictive of SVR than conventional combination therapy in chronic hepatitis C.     

Results of a study of prolonging treatment with pegylated interferon-alpha2a plus ribavirin in HIV/HCV-coinfected patients with no early virological response

OBJECTIVE: To assess the efficacy and safety of an extended treatment period in HIV/hepatitis C virus (HCV)-coinfected patients without early virological response (EVR). METHODS: Patients received pegylated interferon (peg-INF)-alpha2a 180 microg/week plus ribavirin 800 mg/d for 12 weeks. Patients achieving EVR at week 12 continued under therapy for an additional 12 or 36 weeks depending on genotype. Patients without EVR were randomized to complete the standard treatment or treatment lasting 72 weeks (extension arm). RESULTS: One hundred and ten patients were included (mean age 38.7 years, mean weight 68 kg, 74% males, 74% on highly active antiretroviral therapy, mean CD4+ T-cell count 564 cells/mm3). Fifty-one patients harboured genotype 1, 44 genotype 2/3, and 15 genotype 4. Fifty-three had an HCV load >800,000 IU/ml. Premature interruptions occurred in 32.7%. EVR was achieved in 63.6% (51% in genotype 1, 88.6% in genotype 2/3, 33.3% in genotype 4). End-of-treatment response was 52.7% (47.2% in genotype 1, 68.2% in genotype 2/3, 26.7% in genotype 4). Sustained virological response (SVR) was achieved in 41.8% (37.3% in genotype 1, 54.6% in genotype 2/3, 20% in genotype 4). Only one patient allocated to the extended arm achieved SVR. The rate of drop-outs in the extension arm was 68%. The negative predictive value of EVR was 97.5%. CONCLUSIONS: This study shows no benefit of extending therapy in patients without EVR at week 12. Measures to improve adherence to HCV antiviral therapy should be considered when new approaches based on extended periods of treatment are investigated.     

Low response to pegylated interferon plus ribavirin in HIV-infected patients with chronic hepatitis C treated with abacavir

BACKGROUND: There is little information about the influence of antiretroviral drugs on the antiviral activity of pegylated interferon (PEG-IFN) plus ribavirin (RBV) against hepatitis C virus (HCV). METHODS: All HIV-infected patients with chronic hepatitis C who received first-line PEG-IFN plus RBV were retrospectively analyzed. Only patients in whom virological stopping rules were applied and who did not change their antiretrovirals were chosen. Plasma RBV concentrations were measured at week 4. RESULTS: A total of 493 patients (78% males, mean age 41 years, 78% on antiretroviral therapy, mean CD4+ T-cell count 561 cells/microl) fit the study inclusion criteria. Mean baseline serum HCV RNA was 5.89 log10 IU/ml, 65% were infected by genotypes 1 or 4 and 40% had advanced liver fibrosis (Metavir F3F4). The overall rate of sustained virological response (SVR) was 38%. Factors associated with lack of SVR in the multivariate analyses (odds ratio [95% confidence interval], P-value) were higher baseline serum HCV RNA (2.42 per log10 IU/ml [1.31-4.46], 0.005), HCV genotypes 1 or 4 (5.95 [2.50-14.29], < 0.001) and lower RBV plasma trough concentrations (1.74 per microg/ml [1.15-2.63], 0.009). Interestingly, a trend was noticed for abacavir use (2.22 [0.91-5.40], 0.08), which become significant when only considering the subset of patients with RBV plasma levels < 2.3 microg/ml (7.63 [1.39-41.67], 0.02). CONCLUSIONS: The use of abacavir might interfere with the anti-HCV activity of PEG-IFN plus RBV. As both antivirals are guanosine analogues, an inhibitory competition between abacavir and RBV might explain this observation, which is more prominent in patients with lower RBV exposure.     

Dose-dependent and genotype-independent sustained virological response of a 12 week pegylated interferon alpha-2b treatment for acute hepatitis C

OBJECTIVES: The optimal regimen for acute hepatitis C (AHC) is considered to be a 24 week treatment with interferon (IFN) alpha-2b. A 24 week treatment with pegylated IFN (PEG-IFN) alpha-2b is also effective. This study was designed to assess response rates to a 12 week regimen of PEG-IFN alpha-2b. PATIENTS AND METHODS: Patients with AHC were treated with PEG-IFN alpha-2b for 12 weeks in an open, non-randomized, prospective cohort study. Diagnosis of AHC was made with positive serum HCV RNA and elevated alanine aminotransferase (ALT) levels with a documented seroconversion or a known risk factor in the preceding 6 months. Treatment was administered within a median of 31 days (range 0-116) of the ALT level peak at a dosage varying from 1.06 to 1.66 microg/kg/week. The primary end-point was a sustained virological response (SVR). RESULTS: Nineteen patients were treated, of whom 11 patients (57.9%) had HCV genotype 1. Fourteen patients were asymptomatic. An SVR was achieved in 74% of patients and the SVR rate was 100 and 83.3%, respectively, in genotype 1 and non-1 infected patients treated with a dosage>or=1.33 microg/kg, compared with 40 and 50%, respectively, in those who received a lower dosage. An SVR was significantly associated by multivariate analysis only with PEG-IFN dosage>or=1.33 microg/kg/week. No significant association was found with any viral genotype. CONCLUSIONS: The rate of SVR was independent of the HCV genotype and was significantly associated by multivariate analysis only with the higher PEG-IFN dosage. Early identification and treatment of AHC is likely to decrease the burden of chronic hepatitis, especially when caused by HCV genotype 1.