Utility of week-4 viral response to tailor treatment duration in hepatitis C virus genotype 3/HIV co-infected patients

Prevalence of Hepatitis C Virus Genotypes in Pakistan: Current Scenario and Review of Literature

Hepatitis C virus (HCV) is a major public health concern globally, resulting in liver-related complications. Approximately 6% population of Pakistan is infected with HCV. HCV is error prone, due to which it is classified into 7 genotypes and 67 subtypes. HCV genotype determination is critical for treatment and therapy response. In this study, 3,539 samples were collected from 2015 to 2019 from all over Punjab. RNA was extracted from samples using QIA Amp Viral RNA MINI kit (Qiagen, Germany) and viral genotyping was performed. Furthermore, a systemized literature search (2009-2018) was done to analyze the HCV genotype distribution pattern in Pakistan. In Punjab, genotype 3a (86.46%) is most prevalent, followed by untypable (7.17%) and genotype 1a (3.84%) and 3b (1.04%). Mixed genotype constitutes only 0.67% of total infections. Genotype 2a, 2b, 3c, and 4 were found to be rare. Data available from literature review when compiled showed that HCV genotype 3a (58.16%) was predominant in Pakistan, followed by genotypes 3b (9.05%), 2a (6.70%), 1a (6.22%), and 1b (2.39%). The frequency of mixed genotypes was found to be 4% and 12% of untypable HCV variants. This study highlights the HCV genotype distribution pattern in different regions of Pakistan. Therapy response and disease management depend on genotype, so HCV genotype determination is crucial. In Pakistan, the most prevalent genotype is 3a, followed by untypable genotype. Both interferon and sofosbuvir are effective against genotype 3a, but treatment with sofosbuvir has comparatively high sustained virological response, less adverse effects, and more tolerability.

Liver fibrosis, host genetic and hepatitis C virus related parameters as predictive factors of response to therapy against hepatitis C virus in HIV/HCV coinfected patients

OBJECTIVE

To establish the role of liver fibrosis as a predictive tool of response to pegylated interferon alpha (Peg-IFN) and ribavirin (RBV) treatment in human immunodeficiency (HIV)/hepatitis C virus (HCV) coinfected patients, in addition to recognized predictive factors (HCV load, HCV genotype, IL-28B polymorphism).

PATIENTS AND METHODS

A sample of 267 HIV/HCV coinfected patients was treated with Peg-IFN and RBV. Predictive factors of rapid (RVR) and sustained (SVR) virological response were analyzed. Independent variables were age, sex, IL28B, -238 TNF-α and -592 IL-10 polymorphisms, HCV genotype, HCV-RNA levels, significant fibrosis or cirrhosis and CD4+ T cell count.

RESULTS

Patients infected by HCV genotype 1 (n = 187) showed RVR and SVR in 12% and 39% of cases, respectively. The parameters associated with RVR were IL28B genotype CC and plasma HCV-RNA levels <600,000 IU/ml. Advanced liver fibrosis was negatively associated with SVR in patients without RVR. A SVR was obtained in 42% of subjects with HCV genotype 4, and the independent factors associated with SVR were IL28B genotype CC and an HCV-RNA <600,000 IU/ml. A SVR was obtained in 66% of patients with HCV genotypes 2/3; in this case, the independent parameter associated with SVR was the absence of significant liver fibrosis. TNF-α and IL-10 polymorphisms were not associated with SVR, although a significantly higher percentage of -238 TNF-α genotype GG was detected in patients with significant liver fibrosis.

CONCLUSIONS

In HIV/HCV coinfected patients with HCV genotypes 1 or 4, RVR, mainly influenced by genotype IL28B and HCV-RNA levels, reliably predicted SVR after 4 weeks of therapy with Peg-IFN plus RBV. In patients infected by HCV genotype 3, an elevated relapse rate compromised the influence of RVR on SVR. Relapses were related to the presence of advanced liver fibrosis. Liver cirrhosis was associated with a -238 TNF-α polymorphism in these patients.

HIV coinfection with hepatitis C virus: evolving epidemiology and treatment paradigms

Chronic hepatitis C virus (HCV) infection has become a major threat to the survival of human immunodeficiency virus (HIV)-infected persons in areas where antiretroviral therapy is available. In coinfection, viral eradication has been difficult to attain, and HCV therapy is underused. Novel therapies may be particularly beneficial for this population, yet studies lag behind those for HCV monoinfection. Increasingly, incident HCV among HIV-infected men who have sex with men is associated with sexual risk behavior further research should be performed to refine understanding of the causal mechanism of this association. The phenomenon of aggressive hepatic fibrogenesis when HIV infection precedes HCV acquisition requires longer-term observation to ensure optimal timing of HCV therapy. Medical management in coinfection will be improved by enhancing HCV detection, with annual serologic testing, screening with HCV RNA to detect acute infection, and HIV testing of HCV-infected individuals; by addressing HCV earlier in coinfected persons; and by universal consideration for HCV therapy. HCV drug trials in individuals coinfected with HIV should be expedited. HIV/HCV coinfection remains a growing and evolving epidemic; new developments in therapeutics and improved care models offer promise.

Current treatment for chronic hepatitis C virus/HIV-infected individuals: the role of pegylated interferon-alpha and ribavirin

PURPOSE OF REVIEW

Liver disease is an important cause of morbidity and mortality in the era of combination antiretroviral therapy in HIV/hepatitis C virus (HCV) co-infected patients. This review highlights the role of pegylated interferon-alpha (peg-IFN) and ribavirin (RBV) therapy and examines factors associated with response and strategies to maximize responses.

RECENT FINDINGS

HCV viral clearance is lower in HIV co-infected patients than in HCV mono-infected patients. However, in patients who attain sustained response there is clinical benefit in terms of liver disease associated morbidity and mortality and treatment is costeffective. Predictors of response appear similar, although there are a number of modifiable patient-associated and HIV-associated factors that could be addressed. Moreover, the use of weight-based RBV and treatment length guided by early viral responses improve response rate. Avoidance of drug-drug interactions and use of haematopoietic growth factors reduce adverse events and dose reductions and ultimately increase response rates. Very early prediction of treatment futility is promising. Induction dosing strategies have not yielded positive results, though twice weekly peg-IFN-alpha-2a induction therapy merits further investigation.

SUMMARY

Peg-IFN/RBV therapy plays an important role in the management of HCV in HIV-infected patients. Efforts to maximize response to current therapy need to continue while we await new therapies.

Management of HIV and hepatitis virus coinfection

IMPORTANCE OF THE FIELD

Liver disease related to infection with hepatitis C virus (HCV) and/or hepatitis B virus (HBV) is a frequent cause of morbidity and mortality in those infected with the human immunodeficiency virus (HIV) in this era of highly active antiretroviral therapy (HAART). Although progress has been made in the treatment of HBV and HCV in the setting of HIV-coinfection, there is a lack of data in certain areas and several aspects of the management are unclear at this time.

AREAS COVERED IN THIS REVIEW

Available data on the treatment of HBV and HCV infections, especially in the HIV-coinfected patient, are presented. Practical aspects of the management of these patients are reviewed, including diagnosis, treatment indications, monitoring, and toxicities. The impact of HAART on liver disease, end-stage-liver disease, and new therapeutic approaches are also reviewed.

WHAT THE READER WILL GAIN

There are two modalities for the treatment of chronic HBV infection: interferon and nucleos(t)ide reverse transcriptase inhibitors (NRTI). The latter is the mainstream of therapy for HIV-HBV-coinfected patients. The double antiviral activity of NRTI requires coordination and careful selection of treatment for both viruses to avoid selection of resistance mutations and toxicity. Combination of pegylated interferon and ribavirin, the current standard treatment for chronic hepatitis C, has significant toxicity and limited efficacy in HIV-HCV-coinfected individuals. Oral anti-HCV treatments are currently under development and need to be studied in the HIV-coinfected population. Liver transplantation has a better outcome in HBV- than in HCV-HIV-coinfected patients. HAART seems to have a positive impact on the liver disease of HBV- and/or HCV-coinfected subjects but the CD4 threshold above which the benefit might take place is unknown at this time.

TAKE HOME MESSAGE

Anti-HBV treatment in the HIV-coinfected patient relies on the available NRTIs with activity against both viruses. Whereas HBV suppression can be achieved with this approach, toxicities and the selection of HBV-resistant variants result in challenging clinical scenarios. Current anti-HCV treatment (pegylated interferon and ribavirin) has limited efficacy in the HIV-coinfected patient, and STAT-C drugs are eagerly awaited.

Insulin resistance impairs response to interferon plus ribavirin in patients coinfected with HIV and hepatitis C virus

BACKGROUND/AIMS

Controversy exists about whether insulin resistance (IR) affects response to treatment of hepatitis C. We evaluated the effect of IR on sustained virologic response (SVR) in HIV/hepatitis C virus (HCV)-coinfected patients treated with interferon plus ribavirin.

METHODS

We reviewed the clinical records of HIV/HCV-coinfected patients who received interferon plus ribavirin at our institution between July 2000 and March 2007. IR was defined as a homeostasis model assessment ≥ 3.8. SVR was defined as an undetectable HCV RNA at 24 weeks after the end of treatment. Efficacy was evaluated using an on-treatment (OT) analysis. Multivariate logistic regression analysis was used to evaluate factors associated with SVR.

RESULTS

During the study period, 218 patients were treated with interferon plus ribavirin; IR at baseline was available for 162 patients, and 134 were included in the OT analysis; HCV genotype (G) 1/4, 67%; F3-F4 fibrosis, 36%; IR 31%. SVR was achieved in 67 patients (50%) (79% in G 2/3 vs. 38% in G 1/4). IR was associated with a lower SVR [odds ratio (OR), 0.33; 95% confidence interval (CI): 0.15-0.72; P = 0.006). The independent variables related to SVR were genotype 2/3 (OR, 6.7; 95% CI: 2.71-16.98; P < 0.001), absence of IR at baseline (OR, 3.3; 95% CI: 1.36-8.26; P = 0.008), and nadir CD4 T-cell count (OR, 1.002; 95% CI: 1.00-1.00; P = 0.047).

CONCLUSIONS

Our data suggest that IR is an important determinant of SVR in HIV/HCV-coinfected patients treated with interferon plus ribavirin. Strategies to modify IR should be explored to enhance SVR during anti-HCV therapy.

Antiviral treatment for chronic hepatitis C in patients with human immunodeficiency virus

BACKGROUND

Antiviral treatment for chronic hepatitis C may be less effective if patients are co-infected with human immunodeficiency virus (HIV).

OBJECTIVES

To assess the benefits and harms of antiviral treatment for chronic hepatitis C in patients with HIV.

SEARCH STRATEGY

Trials were identified through manual and electronic searches in 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. The last search was May 2009.

SELECTION CRITERIA

Randomised trials comparing at least 12 weeks of any anti-HCV treatment versus another treatment regimen or no treatment. Included patients had chronic hepatitis C and stable HIV irrespective of previous antiviral therapy.

DATA COLLECTION AND ANALYSIS

Data extraction and assessment of risk of bias were done in duplicate. Analysis was by intention-to-treat.

MAIN RESULTS

Fourteen trials were included. None of the included 2269 patients were previously treated for chronic hepatitis C. Peginterferon (either 2a, 180 microgram, or 2b, 1.5 microgram/kg, once weekly) plus ribavirin was more effective in achieving end of treatment and sustained virological response compared with interferon plus ribavirin (5 trials, 1340 patients) or peginterferon (2 trials, 714 patients). The benefit of peginterferon plus ribavirin was seen irrespective of HCV genotype although patients with genotype 1 or 4 had lower response rates (27%) than patients with genotype 2 or 3 (56%). The remaining trials compared different treatment regimens in patients who were treatment naive or had no virological response after three months of treatment, but overall they had not enough power to show any effect of increasing the dose of interferon or adding both amantadine or ribavirin. The overall mortality was 23/2111 patients with no significant differences between treatment regimens. Treatment increased the risk of adverse events including anaemia and flu-like symptoms, and several serious adverse events occurred including fatal lactic acidosis, liver failure, and suicide due to depression.

AUTHORS' CONCLUSIONS

Peginterferon plus ribavirin may be considered a treatment for patients with chronic hepatitis C and stable HIV who have not received treatment for hepatitis C as the intervention may clear the blood of HCV RNA. Supporting evidence comes mainly from the analysis of this non-validated surrogate outcome assessed in comparisons against other antiviral treatments. There is no evidence on treatment of patients who have relapsed or did not respond to previous therapy. Careful monitoring of adverse events is warranted.

Viral hepatitis and HIV co-infection

Chronic hepatitis B virus (HBV) infection is overall recognised in 10% of HIV+ persons worldwide, with large differences according to geographical region. Chronic hepatitis C virus (HCV) infection affects 25% of HIV+ individuals, with greater rates ( approximately 75%) in intravenous drug users and persons infected through contaminated blood or blood products. HIV-hepatitis co-infected individuals show an accelerated course of liver disease, with faster progression to cirrhosis. The number of anti-HBV drugs has increased in the last few years, and some agents (e.g. lamivudine, emtricitabine, tenofovir) also exert significant activity against HIV. Emergence of drug resistance challenges the long-term benefit of anti-HBV monotherapy, mainly with lamivudine. The results using new more potent anti-HBV drugs (e.g. tenofovir) are very promising, with prospects for stopping or even revert HBV-related liver damage in most cases. With respect to chronic hepatitis C, the combination of pegylated interferon plus ribavirin given for 1 year permits to achieve sustained HCV clearance in no more than 40% of HIV-HCV co-infected patients. Thus, new direct anti-HCV drugs are eagerly awaited for this population. Although being a minority, HIV+ patients with delta hepatitis and those with multiple hepatitis show the worst prognosis. Appropriate diagnosis and monitoring of chronic viral hepatitis, including the use of non-invasive tools for assessing liver fibrosis and measurement of viral load, may allow to confront adequately chronic viral hepatitis in HIV+ patients, preventing the development of end-stage liver disease, for which the only option available is liver transplantation. This article forms part of a special issue of Antiviral Research marking the 25th anniversary of antiretroviral drug discovery and development, Vol 85, issue 1, 2010.

Characteristics and treatment outcomes among HIV-infected individuals in the Australian Trial in Acute Hepatitis C

BACKGROUND

The Australian Trial in Acute Hepatitis C (ATAHC) is a National Institutes of Health-funded prospective cohort study of the natural history and efficacy of treatment in individuals with recently acquired hepatitis C. Enrollment is open to both human immunodeficiency virus (HIV)-infected and -uninfected individuals. The aim of this article was to evaluate characteristics and virological outcomes among HIV-infected individuals enrolled in ATAHC.

METHODS

Eligibility criteria included the first positive result of testing for anti-hepatitis C virus (HCV) antibody within 6 months and either clinical hepatitis diagnosed within the past 12 months or documented anti-HCV seroconversion within the past 24 months.

RESULTS

Of the initial 103 patients enrolled, 27 (26%) were HIV infected. HIV-infected patients were more likely to be older, to have HCV genotype 1 infection and high levels of HCV RNA at baseline than were HCV-monoinfected patients. Sexual acquisition accounted for the majority (56%) of HCV infections among HIV-infected patients, compared with only 8% of HCV-monoinfected patients. The median duration from estimated HCV infection to treatment was 30 weeks. Treatment with 24 weeks of pegylated interferon and ribavirin resulted in rates of undetectability of HCV RNA of 95%, 90%, and 80% at weeks 12, 24, and 48, respectively. Undetectability at week 4 was achieved in 44% of patients and yielded positive and negative predictive values for sustained virological response of 100% and 33%, respectively.

CONCLUSIONS

Significant differences were demonstrated between HIV-infected and HIV-uninfected individuals enrolled in ATAHC. Treatment responses among HIV-infected individuals with both acute and early chronic infection are encouraging and support regular HCV screening of high-risk individuals and early treatment for recently acquired HCV infection.

HIV and hepatitis C coinfection

The significant burden of HIV/hepatitis C virus (HCV) coinfection is increasingly recognized worldwide, and in particular within the Asia-Pacific region. Individuals who are coinfected with both viruses are at risk from accelerated liver disease and consequently cirrhosis, liver failure, and hepatocellular carcinoma. In addition, coinfected individuals may have altered immunological responses to HAART and are at increased risk of highly active antiretroviral therapy (HAART)-related hepatotoxicity. Treatment for HCV infection in HIV-infected individuals is with standard pegylated interferon and ribavirin therapy, and all HIV/HCV coinfected subjects should undergo suitability for HCV treatment assessment. Response rates to HCV therapy are generally 10-15% lower than in HCV monoinfection, and therapy may be complicated by issues of drug interactions and significant toxicity. However, greater understanding of baseline factors can contribute to better prediction of treatment outcome, and monitoring of on-treatment virological responses increasingly allows individualization of therapy. Where possible, treatment of HCV is often advisable before HAART is required to avoid the issues of drug interactions on HCV therapy and the risk of HAART-related hepatotoxicity. Early diagnosis of both HIV and HCV infection is essential to most effectively manage HIV-HCV-coinfected individuals. New therapies, including HCV protease and polymerase inhibitors, are in development and may widen therapeutic options for HIV-HCV-coinfected individuals into the future.

Role of rapid virological response in prediction of sustained virological response to Peg-IFN plus ribavirin in HCV / HIV co-infected individuals

The objective of the study was to evaluate the role of rapid virological response (RVR) in predicting sustained virological response (SVR) rates to hepatitis C virus (HCV) therapy. 65 HIV / HCV co-infected patients commenced HCV treatment per protocol. HIV / HCV patients with a mean CD4 count of 502 were treated for 24-48 weeks depending on genotype. Virological response was assessed at weeks 4 (RVR), 12 [early virological response (EVR)], 24, at end of treatment (EOTR) and 24 weeks post-completion of treatment (SVR). Primary end-point was defined as undetectable HCV RNA at 24 weeks post-treatment completion. Fifty-five per cent of co-infected patients were on highly active anti-retroviral therapy. A majority of patient group were male. 60% of HIV / HCV patients achieved SVR (35% genotype 1 / 4; 77% genotype 2 / 3). 24 HIV / HCV patients achieved undetectable HCV levels compared with baseline by week 4. The positive predictive value (PPV) of RVR at week 4 for subsequent SVR in HIV-HCV co-infected patients was 100%; the negative predictive value (NPV) was 57%. Significant variables associated with SVR were: (i) lower median pre-treatment HCV viral load, (ii) genotype 2 / 3 disease and (iii) achievement of RVR. Independent variables associated with RVR were low pre-treatment HCV viral load and genotype 2 / 3 disease. Achievement of RVR, a negative HCV-PCR, at week 4 of treatment is predictive of SVR in this cohort of patients. This may be used to guide optimal treatment duration in patient groups. More significantly, the data serve to highlight the subgroup of patients who, on achieving RVR, should be actively supported to complete HCV treatment with full dose therapy, especially patients co-infected with G2 / 3 disease for whom 6 months' full dose therapy may be sufficient to obtain a SVR.

Sustained virological response based on rapid virological response in genotype-3 chronic hepatitis C treated with standard interferon in the Pakistani population

AIM: To document the sustained virological response (SVR) in rapid virological responders (RVR) of genotype-3 chronic hepatitis C with standard interferon (SdIF).

METHODS: Hepatitis C genotype-3 patients during the period July 2006 and June 2007 were included. Complete blood counts, prothrombin time, ALT, albumin, qualitative HCV RNA were done. SdIF and ribavirin were given for 4 wk and qualitative HCV RNA was repeated. Those testing negative were allocated to group-A while the rest were allocated to group-B. Treatment was continued a total of 16 and 24 wk for group A and B respectively. HCV RNA was repeated after 24 wk of treatment. End virological and sustained virological responses were compared by χ² test. ROC of pretreatment age, ALT and albumin were plotted for failure to achieve SVR.

RESULTS: Of 74 patients treated, RCV RNA after 16 wk of therapy became undetectable in 34 (45.9%) and was detectable in 40 (54.1%) and were allocated to groups A and B respectively. SVR was achieved in 58.8% and 27.8% in groups A and B respectively. SVR rates were significantly higher in patients who had RVR as compared to those who did not (P = 0.0; γ = 2). Both groups combined ETR and SVR were 70% and 33% respectively. ROC plots of pretreatment age, ALT and albumin for SVR showed only ALT to have a significantly large area under the curve.

CONCLUSION: SVR rates were higher in patients who had RVR with SdIF and high pre treatment ALT values correlated to probability of having RVR.

Undetectable hepatitis C virus RNA at week 4 as predictor of sustained virological response in HIV patients with chronic hepatitis C

BACKGROUND

Low baseline serum hepatitis C virus (HCV)-RNA and clearance of viraemia at week 4 with pegylated interferon (pegIFN) plus ribavirin therapy predict sustained virological response (SVR) and enable a shorter duration of therapy in patients with chronic hepatitis C. It is unclear whether this applies to HIV/HCV-co-infected patients.

PATIENTS AND METHODS

In the Peginterferon Ribavirin ESpaña COinfection (PRESCO) trial, 389 co-infected patients received pegIFN-alpha2a 180 microg/week plus ribavirin 1000-1200 mg/day. Patients with HCV-2/3 were treated for 6 or 12 months, whereas patients with HCV-1/4 were treated for 12 or 18 months. For each genotype, baseline HCV-RNA and rapid virological response (RVR), defined as under 50 IU/ml HCV-RNA at week 4, were evaluated as predictors of SVR in an 'on-treatment' analysis.

RESULTS

Overall, SVR was achieved by 193 patients (49.6%), 68/191 (35.6%) with genotype 1, 110/152 (72.4%) with genotypes 2/3 and 15/46 (32.6%) with genotype 4. RVR was the best predictor of SVR regardless of HCV genotype. Only for HCV-1 patients, baseline HCV-RNA less than 500 000 IU/ml was also associated with SVR. In HCV-3 patients RVR had a positive predictive value (PPV) for SVR of 90%, with treatment for 24 or 48 weeks. The PPV of SVR for patients with RVR was 69% for HCV-1 and 83% for HCV-4.

CONCLUSION

Undetectable HCV-RNA at week 4 is the best predictor of curing chronic hepatitis C in HCV/HIV-co-infected patients. In HCV-1 patients, baseline HCV-RNA also predicts response. HIV patients with HCV-3 and RVR may permit shortening therapy duration to only 24 weeks of pegIFN plus 1000-1200 mg ribavirin.

The changing epidemiology of hepatitis C virus infection in Europe

The epidemic of hepatitis C virus (HCV) infection in Europe is continuously evolving and epidemiological parameters (prevalence, incidence, disease transmission patterns and genotype distribution) have changed substantially during the last 15 years. Four main factors contribute to such changes: increased blood transfusion safety, improvement of healthcare conditions, continuous expansion of intravenous drug use and immigration to Europe from endemic areas. As a result, intravenous drug use has become the main risk factor for HCV transmission, prevalent infections have increased and genotype distribution has changed and diversified. Hence, prevalence data from studies conducted a decade ago may not be useful to estimate the current and future burden of HCV infection and additional epidemiological studies should be conducted, as well as new preventive strategies implemented to control the silent epidemic. This review summarizes recently published data on the epidemiology of HCV infection in Europe focusing on the factors currently shaping the epidemic.

Early Monitoring of Ribavirin Serum Concentration is not Useful to Optimize Hepatitis C Virus treatment in HIV-Coinfected Patients

Background

Emerging data suggest that higher ribavirin (RBV) exposure could improve early hepatitis C virus (HCV) response. Furthermore, interindividual RBV bioavailability shows high variation, and dose-limiting haemolytic anaemia is a common adverse event. Therefore, it has been suggested that monitoring RBV serum levels could be used to drive dose modification and to optimize management of HCV-infected patients receiving combination treatment.

Methods

To assess the effect of RBV serum levels on HCV RNA clearance at week 4 and 12 of treatment, and to determine the correlation between RBV serum concentration and haemoglobin decrease, RBV trough levels were measured by HPLC in stored serum samples obtained from 94 HCV-HIV-coinfected patients at week 4 and 12 of treatment with peginterferon-α2b (1.5 μg/kg/weekly) plus ribavirin (800–1,200 mg/day).

Results

The median RBV levels increased from 1.70 μg/ml at week 4 to 1.97 μg/ml at week 12 of treatment ( P=0.001) and were independently predicted by weight-adjusted dose of RBV and co-administration of tenofovir. Haemoglobin drop was higher among patients who received zidovudine and weakly correlated with RBV level. Although RBV concentration was lower in genotype 1 or 4 HCV-infected patients who cleared the virus at treatment week 4, the ability of this parameter to discriminate between responders and non-responders at treatment week 4 and 12 was poor.

Conclusion

Intracellular RBV accumulation early in treatment might improve the kinetics of HCV response in difficult to treat patients. Although this hypothesis and the potential interaction between RBV and tenofovir warrant further research, our data do not support RBV serum monitoring as a tool to optimize treatment in HCV-HIV-coinfected patients.

Management of HIV/hepatitis C virus-coinfected patient non-responders to hepatitis C virus antiviral therapy and relapsers

PURPOSE OF REVIEW

To examine recent developments in the management of HIV/hepatitis C virus-coinfected patients who relapsed or who responded poorly to initial therapy, with particular emphasis on peginterferon plus ribavirin.

RECENT FINDINGS

End-stage liver disease is the first cause of non-AIDS-related mortality in patients on antiretroviral therapy. A pool analysis of recent studies suggested that only 33% of HIV/hepatitis C virus-coinfected patients will achieve sustained virological response with peginterferon plus ribavirin. A substudy of the APRICOT trial shows that this strategy will benefit liver histology even in non-responding patients. The management of side effects is important and, according to a recent study, erythropoietin can improve clinical outcomes of hepatitis C virus therapy, although no direct association between response and the control of haematological toxicity was demonstrated. Patients who did not clear hepatitis C virus RNA with a slow virological response to previous courses of peginterferon and ribavirin might benefit from prolonging therapy to up to 72 weeks.

SUMMARY

Re-treatment strategies in non-responders to previous interferon-based therapies and relapsers should consider the previous virological response profile and ensure that treatment-related toxicity is controlled to avoid dose reductions or premature treatment interruptions. Further studies are needed to optimize therapeutic regimens.

Hepatitis C viral kinetics during treatment of hepatitis C virus/HIV coinfected patients

PURPOSE OF REVIEW

Studies of hepatitis C virus and HIV kinetics during treatment have been instrumental in elucidating the viral lifecycle and mechanisms of action of antiviral therapies. We sought to review data on hepatitis C virus kinetics in hepatitis C virus/HIV coinfected patients and to illustrate how viral kinetics might direct therapeutic decisions in these patients.

RECENT FINDINGS

Few studies have so far analysed the dynamic changes in hepatitis C virus RNA after treatment initiation in hepatitis C virus/HIV coinfected patients. These studies applied mathematical models previously developed in hepatitis C virus mono-infected patients, and the results obtained did not reveal major differences in viral kinetics between the two patient groups. Similar to mono-infected patients, early measurements of hepatitis C virus RNA levels after treatment initiation have been shown to have utility in predicting treatment response in coinfected patients.

SUMMARY

Confirmatory studies are required to determine definitively whether differences exist between hepatitis C virus kinetics in mono compared with coinfected patients. With additional data, these methods have the potential to direct decisions in hepatitis C virus/HIV coinfection.

Management and therapy of chronic hepatitis C in HIV

PURPOSE OF REVIEW

Chronic hepatitis C is currently one of the leading causes of hospitalization and death in HIV+ persons. Treatment is particularly challenging in coinfected patients due to lower efficacy and more side effects.

RECENT FINDINGS

The combination of pegylated interferon plus ribavirin is the current treatment of choice. In the absence of contraindications, treatment should be provided with no restrictions up front (e.g., asking unnecessarily for a liver biopsy) and revisited at weeks 4 and 12. Treatment should only be continued in early virological responders. The use of standard ribavirin doses (1000-1200 mg/day) and for at least 12 months is crucial to maximize the effect of therapy. In patients with rapid virological response (undetectable viraemia at week 4), shorter periods of therapy (24 weeks) may be advisable for hepatitis C virus genotypes 2 and 3. Patients with low CD4 percentages should defer treatment and prioritize highly active antiretroviral therapy. Didanosine should never be co-administered with ribavirin due to potential life-threatening complications. When possible, zidovudine, stavudine and abacavir should be replaced by other agents having no deleterious interactions with ribavirin.

SUMMARY

The treatment of chronic hepatitis C has become a priority in hepatitis C virus/HIV-coinfected patients, and the best results are obtained by tailoring therapy to the individual patient's characteristics.