Predictive Value of Early Virologic Response in HIV/Hepatitis C Virus-Coinfected Patients Treated With an Interferon-Based Regimen Plus Ribavirin

In HIV/hepatitis C virus co-infected patients, higher 25-hydroxyvitamin D concentrations were not related to hepatitis C virus treatment responses but were associated with ritonavir use

BACKGROUND

Among patients with hepatitis C virus (HCV) monoinfection, 25-hydroxyvitamin D [25(OH)D] concentrations are positively associated with a response to peg-interferon/ribavirin. Data on the relation between 25(OH)D concentrations and HCV treatment response in HIV-infected patients are limited.

OBJECTIVE

The objective was to determine whether baseline 25(OH)D concentrations predict virologic response in HIV/HCV co-infected patients and to examine variables associated with 25(OH)D concentrations ≥30 ng/mL.

DESIGN

Data and samples from 144 HCV genotype 1, treatment-naive patients from a completed HCV treatment trial were examined in this retrospective study. Early virologic response (EVR) was defined as ≥2 log10 reduction in HCV RNA and/or HCV RNA <600 IU/mL at week 12 of peg-interferon/ribavirin treatment. Baseline 25(OH)D was measured by liquid chromatography/tandem mass spectrometry.

RESULTS

Compared with the non-EVR control group (n = 68), the EVR group (n = 76) was younger, had fewer cirrhotic subjects, had a higher proportion with the IL28B CC genotype, had a higher albumin concentration, and had a lower HCV viral load at baseline (P ≤ 0.05). The difference in baseline 25(OH)D concentrations between EVR and non-EVR patients was not statistically significant (median: 25 ng/mL compared with 20 ng/mL; P = 0.23). Similar results were found for sustained virologic response (SVR). In multivariable analysis, white and Hispanic race-ethnicity (OR: 6.26; 95% CI: 2.47, 15.88; P = 0.0001) and ritonavir use (OR: 2.68; 95% CI: 1.08, 6.65; P = 0.033) were associated with higher 25(OH)D concentrations (≥30 ng/mL).

CONCLUSION

Baseline 25(OH)D concentrations did not predict EVR or SVR. Because ritonavir impairs the conversion of 25(OH)D to the active metabolite, utilization of 25(OH)D may have been impaired in subjects taking ritonavir. This trial was registered at www.clinicaltrials.gov as NCT00078403.

IL28RA polymorphism is associated with early hepatitis C virus (HCV) treatment failure in human immunodeficiency virus-/HCV-coinfected patients

Due to the poor rate of response to hepatitis C virus (HCV) with pegylated interferon and ribavirin treatment in HCV/HIV coinfected patients, key factors for predicting failure would be useful. We performed a retrospective study on 291 patients on HCV treatment, who had early virological response (EVR) data. IL28B and IL28RA polymorphisms were performed using the GoldenGate(®) assay. Unfavourable genotypes at IL28B (rs12980275 AG/GG and rs8099917 GT/GG) and an unfavourable allele at IL28RA (rs10903035 G) were associated with early treatment failure. However, only the rs12980275 AG/GG genotype and rs10903035 G allele remained independently associated with early failure in the overall population (OR = 4.15 (95% CI = 1.64-10.54) and OR = 2.00 (95% CI = 1.19-3.36), respectively) as well as in GT1/4 patients (OR = 5.07 (95% CI = 1.81-14.22) and OR = 2.03 (95% CI = 1.13-3.66), respectively). Next, a decision tree showed early treatment failure increased from 37.1% to 65.5% when the unfavourable rs12980275 AG/GG and rs10903035 AG/GG genotypes and HCV-RNA≥ 500.000 IU/mL were taken into account in GT1/4 patients. In contrast, the failure rate decreased from 37.1% to 11.9% when the favourable rs12980275 AA and rs10903035 AA genotypes were detected. The percentage of patients correctly classified was 78.4%, and AUROC was 0.802 ± 0.028. Regarding GT3 patients, the presence of the GCGCA haplotype (all unfavourable alleles) was associated with early treatment failure, while no association was observed for the IL28B polymorphisms. In conclusion, the IL28RA polymorphism was associated with early treatment failure independently of the IL28B SNPs. The combination of IL28B and IL28RA polymorphisms might be a valuable tool for predicting early treatment failure before starting HCV treatment.

Pharmacogenetics of efficacy and safety of HCV treatment in HCV-HIV coinfected patients: significant associations with IL28B and SOCS3 gene variants

BACKGROUND AND AIMS

This was a safety and efficacy pharmacogenetic study of a previously performed randomized trial which compared the effectiveness of treatment of hepatitis C virus infection with pegylated interferon alpha (pegIFNα) 2a vs. 2b, both with ribavirin, for 48 weeks, in HCV-HIV coinfected patients.

METHODS

The study groups were made of 99 patients (efficacy pharmacogenetic substudy) and of 114 patients (safety pharmacogenetic substudy). Polymorphisms in the following candidate genes IL28B, IL6, IL10, TNFα, IFNγ, CCL5, MxA, OAS1, SOCS3, CTLA4 and ITPA were assessed. Genotyping was carried out using Sequenom iPLEX-Gold, a single-base extension polymerase chain reaction. Efficacy end-points assessed were: rapid, early and sustained virological response (RVR, EVR and SVR, respectively). Safety end-points assessed were: anemia, neutropenia, thrombocytopenia, flu-like syndrome, gastrointestinal disturbances and depression. Chi square test, Student's T test, Mann-Whitney U test and logistic regression were used for statistic analyses.

RESULTS

As efficacy is concerned, IL28B and CTLA4 gene polymorphisms were associated with RVR (p<0.05 for both comparisons). Nevertheless, only polymorphism in the IL28B gene was associated with SVR (p = 0.004). In the multivariate analysis, the only gene independently associated with SVR was IL28B (OR 2.61, 95%CI 1.2-5.6, p = 0.01). With respect to safety, there were no significant associations between flu-like syndrome or depression and the genetic variants studied. Gastrointestinal disturbances were associated with ITPA gene polymorphism (p = 0.04). Anemia was associated with OAS1 and CTLA4 gene polymorphisms (p = 0.049 and p = 0.045, respectively), neutropenia and thromobocytopenia were associated with SOCS3 gene polymorphism (p = 0.02 and p = 0.002, respectively). In the multivariate analysis, the associations of the SOCS3 gene polymorphism with neutropenia (OR 0.26, 95%CI 0.09-0.75, p = 0.01) and thrombocytopenia (OR 0.07, 95%CI 0.008-0.57, p = 0.01) remained significant.

CONCLUSIONS

In HCV-HIV coinfected patients treated with PegIFNα and ribavirin, SVR is associated with IL28B rs8099917 polymorphism. HCV treatment-induced neutropenia and thrombocytopenia are associated with SOCS3 rs4969170 polymorphism.

IL28B alleles exert an additive dose effect when applied to HCV-HIV coinfected persons undergoing peginterferon and ribavirin therapy

BACKGROUND

Genetic studies have demonstrated a strong association between single nucleotide polymorphisms (SNPs) at IL28B and response to treatment with peginterferon (PEG) and ribavirin (RBV) in HCV monoinfected persons. We sought to test these associations in a prospective PEG / weight based ribavirin (WBR) treatment trial (ACTG A5178) (National Institution of Health registration number NCT00078403) in persons with HCV-HIV coinfection, and to develop a prediction score.

METHODS

We selected subjects enrolled in A5178 who completed at least the first 12 weeks of the trial and had DNA available, and genotyped three SNPs at IL28B (rs12979860, rs12980275, rs8099917). We used multivariate logistic regression analysis to evaluate the association between IL28B SNPs and HCV treatment outcomes and to develop the prediction score.

RESULTS

231 HCV/HIV coinfected subjects were included. We observed a strong association between IL28B genotype and response to therapy among those with genotypes 1 or 4 (odds ratio for complete early virologic responses (cEVR) and sustained virologic response (SVR) was 2.98 [1.7-5.3] and 3.4 [1.7-6.9], respectively, for each additional copy of the C allele of rs12979860). Differences in frequency of the responder allele explained some of the discrepancy in HCV treatment outcomes between blacks and whites. A simple pretreatment prediction score that incorporates the IL28B genotype and baseline HCV viral load has a 93% negative predictive value (NPV) for SVR.

CONCLUSIONS

IL28B SNPs have an additive allele dose effect in predicting HCV treatment outcomes in HCV/HIV coinfected persons and can be incorporated into a simple pretreatment prediction score that could minimize the risk of exposure to PEG/RBV therapy for persons with unfavorable scores.

Early viral kinetics: a novel guide for optimal dosing frequency of pegylated interferon-α-2a in HIV/HCV-coinfected patients

The success rate in HCV treatment of HIV/HCV-coinfected patients is still unsatisfactory and new strategies are required to improve the effectiveness of current regimens and eventually optimize the oncoming new antiviral drugs. This article assesses the findings of a recently published paper comparing pharmacokinetics, pharmacodynamics and HCV decay with twice-weekly dosing of pegylated IFN-α-2a versus the standard weekly dosing, and weight-based ribavirin. A more rapid HCV-RNA decline was observed in the twice-weekly pegylated interferon arm and associated with a higher induction of interferon-stimulated genes, despite a similar pharmacokynetic profile between the two dosing schedules. This promising novel therapeutic approach to improve sustained virologic response in difficult-to-treat populations is discussed in relation to the key findings of the article.

[Human immunodeficiency virus infection and viral hepatitis]

Hepatic complications currently represent one of the leading reasons for medical consultations, hospitalisation, and death in the HIV-infected population. This is due to a large extent to viral hepatitis, given its disproportionate frequency in this population. Chronic hepatitis B affects 5-10% of the HIV-infected population. Vaccination has reduced the incidence of liver disease related to hepatitis-B virus (HBV), and the availability of tenofovir has dramatically improved the prognosis of HIV/HBV carriers. Delta hepatitis affects around 15% of HIV-infected individuals in Europe harbouring positive HBsAg. It has the worst prognosis, given its accelerated course to cirrhosis and the absence of successful therapy. Lastly, chronic hepatitis C is the major cause of liver disease in the HIV population. Although classically linked to persons infected parenterally (i.e., intravenous drug users), outbreaks of acute hepatitis C among homosexual men have been reported over the last decade. Treatment with pegylated interferon plus ribavirin provides a cure in less than 40% of patients. However, the introduction of new direct acting antivirals against hepatitis- C virus (HCV) (telaprevir, boceprevir) has revolutionised the field, as HAART did in 1996 in the HIV field, improving the prognosis of co-infected patients. However, interactions between these drugs and antiretroviral agents and the risk of selective resistance pose huge threats in this population.

Very early prediction of response to HCV treatment with PEG-IFN-alfa-2a and ribavirin in HIV/HCV-coinfected patients

The objective of this study was to find very early viral kinetic markers to predict nonresponse to hepatitis C virus (HCV) therapy in a group of human immunodeficiency virus (HIV)/HCV-coinfected patients. Twenty-six patients (15 HCV genotype-1 and 11 genotype-3) were treated with a 48-week regimen of peginterferon-alfa-2a (PEG-IFN) (180 μg/week) and weight-based ribavirin (11 mg/kg/day). Samples were collected at baseline; 4, 8, 12, 18, 24, 30, 36 and 42 h; days 2, 3, 4, 7, 8, 15, 22, 29, 43 and 57 then weekly and monthly. Five patients discontinued treatment. Seven patients (27%) achieved a sustained virological response (SVR). Nadir HCV RNA levels were observed 1.6 ± 0.3 days after initiation of therapy, followed by a 0.3- to 12.9-fold viral rebound until the administration of the second dose of PEG-IFN, which were not associated with SVR or HCV genotype. A viral decline <1.19 log for genotype-1 and <0.97 log for genotype-3, 2 days after starting therapy, had a negative predictive value (NPV) of 100% for SVR. The day 2 virological response had a similar positive predictive value for SVR as a rapid virological response at week 4. In addition, a second-phase viral decline slope (i.e., measured from day 2 to 29) <0.3 log/week had a NPV = 100% for SVR. We conclude that first-phase viral decline at day 2 and second-phase viral decline slope (<0.3 log/week) are excellent predictors of nonresponse. Further studies are needed to validate these viral kinetic parameters as early on-treatment prognosticators of nonresponse in patients with HCV and HIV.

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.

Therapeutic response to peg-IFN-alpha-2b and ribavirin in HIV/HCV co-infected African-American and Caucasian patients as a function of HCV viral kinetics and interferon pharmacodynamics

METHOD

In this study we sought to characterize the relationship between several pharmacokinetic and pharmacodynamic parameters and virologic responses among HIV/hepatitis C virus genotype-1 co-infected patients receiving pegylated interferon-alpha-2b (peg-IFN2b) and ribavirin. We also tried to establish the underlying mechanisms that lead to poor sustained virologic responder rates observed with African-Americans against Caucasians and compared their results with those observed in a cohort of hepatitis C virus mono-infected patients.

RESULTS

Among our studied population, a viral decline of more than 1.0 log at day 3 combined with viral load of less than 5.0 log IU/ml at day 28 predicted sustained virologic responders with negative predictive value 100% and positive predictive value 100%. African-Americans had significantly (P < 0.01) slower hepatitis C virus viral kinetics as compared to Caucasians. However, peg-IFN2b concentrations and pharmacokinetic parameters, peg-IFN2b(max) and peg-IFN2b half-life, were similar in both groups and did not predict sustained virologic responders. Nevertheless, the pharmacodynamic parameter EC(50), estimated from nonlinear fitting of the viral kinetics together with peg-IFN2b concentration data, showed that HIV/ hepatitis C virus co-infected African-Americans have lower sensitivity to interferon-alpha thus giving rise to slower viral decline. The combined pharmacokinetic/pharmacodynamic parameter IFN(max)/EC(90) was an excellent predictor of sustained virologic responders, thus showing the importance of maintaining peg-IFN2b levels above EC(90) to achieve successful treatment.

CONCLUSION

Further studies are needed to evaluate whether these pharmacodynamic predictions are a result of differential host response to peg-IFN2b or other viral factors conferring relative resistance to peg-IFN2b.

Randomized trial comparing pegylated interferon alpha-2b versus pegylated interferon alpha-2a, both plus ribavirin, to treat chronic hepatitis C in human immunodeficiency virus patients

Although two pegylated interferons (Peg-IFN) are available to treat chronic hepatitis C virus (HCV) infection, no head-to-head comparative studies have been published. We aim to compare the efficacy and safety of PEG IFN alfa-2b (PEG 2b) versus PEG IFN alfa-2a (PEG 2a), plus ribavirin (RBV). A prospective, randomized, multi-center, open-label clinical trial including 182 human immunodeficiency virus (HIV)-hepatitis C virus (HCV) patients naïve for HCV therapy was performed. Patients were assigned to PEG 2b (80-150 mug/week; n = 96) or PEG 2a (180 mug/week; n = 86), plus RBV (800-1200 mg/day) for 48 weeks. The primary endpoint was sustained virological response (SVR: negative HCV-RNA 24 weeks after completion of treatment). At baseline, both groups were well balanced: 73% male; 63% HCV genotype 1 or [corrected] 4; 29% had fibrosis index of 3 or greater. The overall SVR was 44% (42% PEG 2b versus 46% PEG 2a, P = 0.65). Among genotypes 1 or [corrected] 4, SVRs were 28% versus 32% (P = 0.67) and 62% versus 71% (P = 0.6) in genotypes 2 or [corrected] 3 for PEG 2b and PEG 2a, respectively. Early virological response (EVR; >or=2 log reduction from baseline or negative HCV-RNA at week 12) was 70% in the PEG 2b group and 80% in the PEG 2a group (P = 0.13), reaching a positive predictive value of SVR of 64% and a negative predictive value of 100% in both arms. Side effects were present in 96% of patients but led to treatment discontinuation in 10% of patients (8% on PEG 2b and 13% on PEG 2a, P = 0.47).

CONCLUSION

In patients with HIV, HCV therapy with PEG 2b or PEG 2a plus RBV had no significant differences in efficacy and safety.

Serum concentrations of ribavirin and pegylated interferon and viral responses in patients infected with HIV and HCV

The hepatitis C virus (HCV) infects a substantial proportion of patients infected with human immunodeficiency virus (HIV). Patients infected with both HCV and HIV respond poorly to anti-HCV treatment with pegylated interferon alpha and ribavirin. But few data are available on the influence of ribavirin and interferon concentrations on treatment outcome for these patients. This study investigated the relationship between the serum pegylated interferon and ribavirin concentrations 3 and 6 months after treatment initiation, and treatment outcome in 35 HCV-HIV coinfected patients. The pegylated interferon and ribavirin concentrations at months 3 and 6 were similar. The pegylated interferon concentrations at 3 months in responders and nonresponders were similar. However, responders tended to have higher ribavirin concentrations (2,322 ng/ml) than nonresponders (1,833 ng/ml; P = 0.08). Responders infected with HCV genotype 1 or 4 had higher ribavirin concentrations (2,672 ng/ml) than did similarly infected nonresponders (1,758 ng/ml; P = 0.04). ROC curve analysis showed that a ribavirin concentration of 2,300 ng/ml was the best threshold for predicting a nonresponse (ROC area = 0.80 +/- 0.12). Thus ribavirin concentrations influence treatment outcome in HIV patients infected with HCV genotype 1 or 4. Monitoring ribavirin concentrations could help adapt ribavirin concentrations and improve the sustained virological response.

Hepatitis infection in the treatment of opioid dependence and abuse

Many new and existing cases of viral hepatitis infections are related to injection drug use. Transmission of these infections can result directly from the use of injection equipment that is contaminated with blood containing the hepatitis B or C virus or through sexual contact with an infected individual. In the latter case, drug use can indirectly contribute to hepatitis transmission through the dis-inhibited at-risk behavior, that is, unprotected sex with an infected partner. Individuals who inject drugs are at-risk for infection from different hepatitis viruses, hepatitis A, B, or C. Those with chronic hepatitis B virus infection also face additional risk should they become co-infected with hepatitis D virus. Protection from the transmission of hepatitis viruses A and B is best achieved by vaccination. For those with a history of or who currently inject drugs, the medical management of viral hepatitis infection comprising screening, testing, counseling and providing care and treatment is evolving. Components of the medical management of hepatitis infection, for persons considering, initiating, or receiving pharmacologic therapy for opioid addiction include: testing for hepatitis B and C infections; education and counseling regarding at-risk behavior and hepatitis transmission, acute and chronic hepatitis infection, liver disease and its care and treatment; vaccination against hepatitis A and B infection; and integrative primary care as part of the comprehensive treatment approach for recovery from opioid abuse and dependence. In addition, participation in a peer support group as part of integrated medical care enhances treatment outcomes. Liver disease is highly prevalent in patient populations seeking recovery from opioid addiction or who are currently receiving pharmacotherapy for opioid addiction. Pharmacotherapy for opioid addiction is not a contraindication to evaluation, care, or treatment of liver disease due to hepatitis virus infection. Successful pharmacotherapy for opioid addiction stabilizes patients and improves patient compliance to care and treatment regimens as well as promotes good patient outcomes. Implementation and integration of effective hepatitis prevention programs, care programs, and treatment regimens in concert with the pharmacological therapy of opioid addiction can reduce the public health burdens of hepatitis and injection drug use.

CTN-194 (PICCO): design of a trial of citalopram for the prevention of depression and its consequences in HIV-hepatitis C co-infected individuals initiating pegylated interferon/ribavirin therapy

Hepatitis C (HCV)-related end stage liver disease is a primary cause of morbidity and mortality in people with HIV. Despite this, co-infected patients have low rates of HCV treatment initiation and completion. This is in large part due to the risk of pegylated-interferon alpha (PEG-IFN-alpha)-related neuropsychiatric complications. We describe the design of a multicentre randomized, placebo-controlled trial that evaluates whether antidepressant prophylaxis is superior to early detection and treatment of depression in increasing the successful completion of HCV therapy. Seventy-six HIV+ adults with chronic HCV infection requiring therapy and with no contraindications to PEG-IFN-alpha/ribavirin will be randomized in a 1:1 ratio to receive citalopram or placebo starting three weeks prior to HCV treatment. A novel aspect of the trial design is the built-in management of emergent depression while maintaining the blinded treatment assignment. This will permit the comparison of prophylactic versus therapeutic use of citalopram. The primary outcome is the average proportion of prescribed PEG-IFN-alpha and ribavirin doses taken per month at weeks 12 and 24, and will be compared between treatment arms. The study will also compare the development of moderate-to-severe depression between treatment arms. A unique feature of this trial will be the use of Telepsychiatry to standardize observer-administered neuropsychiatric evaluations. Assessments of anxiety, quality of life, and adherence to therapy, as well as pathogenetic studies of neuropsychiatric side effects, will be conducted. Intention-to-treat analyses using random regression modeling will be employed to analyze longitudinal data on prescribed PEG-IFN-alpha and ribavirin doses. Survival analyses will be used to compare the time to the development of depression between the two arms. Effective prevention of a broad range of neuropsychiatric symptoms by citalopram has the potential to diminish PEG-IFN-alpha associated morbidity and consequently, allow a greater number of patients to complete full therapy.

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.