Efficacy of pegylated interferon plus ribavirin treatment in HIV/hepatitis C virus co-infected patients receiving abacavir plus lamivudine or tenofovir plus either lamivudine or emtricitabine as nucleoside analogue backbone

Hepatitis C virus treatment failure: Clinical utility for testing resistance-associated substitutions

The hepatitis C virus has a high mutation capacity that leads to the emergence of resistance-associated substitutions (RAS). However, the consequence of resistance selection during new direct-acting antiviral drug (DAA) treatment is not necessarily the therapeutic failure. In fact, DAA treatment has shown a high rate (> 95%) of sustained virological response even when high baseline RAS prevalence has been reported. In the context of RAS emergence and high rates of sustained viral response, the clinical relevance of variants harboring RAS is still controversial. Therefore, in order to summarize the data available in international guidelines, we have reviewed the clinical utility of testing RAS in the era of new pangenotypic DAA drugs.

Drug-drug interactions with candidate medications used for COVID-19 treatment: An overview

Drug-drug interaction (DDI) is a common clinical problem that has occurred as a result of the concomitant use of multiple drugs. DDI may occur in patients under treatment with medications used for coronavirus disease 2019 (COVID-19; i.e., chloroquine, lopinavir/ritonavir, ribavirin, tocilizumab, and remdesivir) and increase the risk of serious adverse reactions such as QT-prolongation, retinopathy, increased risk of infection, and hepatotoxicity. This review focuses on summarizing DDIs for candidate medications used for COVID-19 in order to minimize the adverse reactions.

Plasma and intracellular ribavirin concentrations are not significantly altered by abacavir in hepatitis C virus-infected patients

OBJECTIVES

The objective of this study was to evaluate the effects of abacavir on intracellular ribavirin triphosphate and plasma ribavirin trough concentrations.

METHODS

Hepatitis C virus-infected subjects who had been cured or failed prior treatment were randomized to 8 weeks of ribavirin alone (N = 14; weight-based dosing) or weight-based ribavirin + abacavir (N = 14; 300 mg orally every 12 h). Ribavirin trough concentrations were measured on days 14, 28, 42 and 56; PBMCs for ribavirin triphosphate determination were sampled on days 28 and 56, pre-dose and at 6 and 12 h post-dose. ClinicalTrials.gov: NCT01052701.

RESULTS

Twenty-six subjects completed the study (24 males, 17 Caucasians, median age 52 years); 2 were excluded for missed pharmacokinetic visits. Fourteen subjects received ribavirin + abacavir and 12 received ribavirin alone. Mean ± SD plasma ribavirin trough concentrations (μg/mL) on days 14, 28, 42 and 56, respectively, were not significantly different with coadministration of abacavir (1.54 ± 0.60, 1.93 ± 0.54, 2.14 ± 0.73 and 2.54 ± 1.05) compared with ribavirin alone (1.48 ± 0.32, 2.08 ± 0.41, 2.32 ± 0.47 and 2.60 ± 0.62) (P > 0.40). Mean ribavirin triphosphate intracellular concentrations (pmol/10(6) cells) on days 28 and 56, respectively, did not differ statistically between abacavir users (11.98 ± 9.86 and 15.87 ± 12.52) and non-users (15.91 ± 15.58 and 15.93 ± 12.69) (P > 0.4). Adverse events were mild or moderate, except for three grade 3 occurrences of transaminitis, cholecystitis and low absolute neutrophil count that resolved and were judged not attributable to study medications.

CONCLUSIONS

Abacavir did not significantly alter ribavirin or ribavirin triphosphate concentrations.

Smit C, Arends J, Peters L, Montforte AD, Dabis F, Zangerle R, Daikos G, Mussini C, Mallolas J, de Wit S, Zinkernagel A, Cosin J, Chene G, Raben D, Rockstroh J. Effect of abacavir on sustained virologic response to HCV treatment in HIV/HCV co-infected patients, Cohere in Eurocoord

BACKGROUND

Contradicting results on the effect of abacavir (ABC) on hepatitis C virus (HCV) treatment responses in HIV/HCV co-infected patients have been reported. We evaluated the influence of ABC on the response to pegylated interferon (pegIFN) and ribavirin (RBV)-containing HCV treatment in HIV/HCV co-infected patients in a large European cohort collaboration, including data from different European countries.

METHODS

HIV/HCV co-infected patients were included if they were aged ≥16 years, received pegIFN alfa-2a or 2b and RBV combination treatment and were enrolled in the COHERE cohort collaboration. Logistic regression was used to evaluate the impact of abacavir on achieving a sustained virologic response (SVR) to HCV treatment.

RESULTS

In total 1309 HIV/HCV co-infected patients who had received HCV therapy were included, of whom 490 (37 %) had achieved an SVR. No statistically significant difference was seen for patients using ABC-containing regimens compared to patients using an emtricitabine + tenofovir (FTC + TDF)-containing backbone, which was the most frequently used backbone. In the multivariate analyses, patients using a protease inhibitor (PI)-boosted regimen were less likely to achieve an SVR compared to patients using a non-nucleoside reverse-transcriptase inhibitor (NNRTI)-based regimen (OR: 0.61, 95 % CI: 0.41-0.91). The backbone combinations zidovudine&lamivudine (AZT + 3TC) and stavudine&lamivudine (d4t + 3TC) were associated with lower SRV rates (0.45 (0.24-0.82) and 0.46 (0.22-0.96), respectively).

CONCLUSION

The results of this large European cohort study validate that SVR rates are generally not affected by ABC. Use of d4T or AZT as part of the HIV treatment regimen was associated with a lower likelihood of achieving an SVR.

The 2015 Clinical Guidelines for the Diagnosis and Treatment of HIV/AIDS in HIV-Infected Koreans

The Committee for Clinical Guidelines for the Diagnosis and Treatment of HIV/AIDS of the Korean Society for AIDS was founded in 2010. The first edition of the Korean guidelines was published in 2011, and revised in 2013. The recommendations in the guideline contain important information for physicians working with HIV/AIDS in the clinical field. However, due to the rapid discovery of new data in the field of HIV and the evolution of the clinical environment in Korea, it has become necessary to revise the guideline again. This guideline aims to provide up-to-date comprehensive information regarding the diagnosis and management of HIV/AIDS in Korea. This guideline deals with issues regarding the initial assessment of newly diagnosed patients, timing of antiretroviral treatment (ART) initiation, preferred ART regimens in treatment-naïve as well as treatment-experienced patients and special populations such as HBV/HCV co-infected patients, or pregnant women. A brief summary of the revised guidelines and key changes to the original version of the guidelines are summarized below.

Hepatitis C virus infection in patients with HIV-1: epidemiology, natural history and management

Hepatitis C virus (HCV)-related liver diseases have contributed to increased morbidity and mortality in HIV-1-infected individuals in the era of effective antiretroviral therapy. HCV transmission patterns have changed among the HIV co-infected population during the last decade, with acute HCV infection emerging worldwide. HIV infection accelerates the progression of HCV-related liver diseases and consequently cirrhosis, liver failure, and hepatocellular carcinoma. However, the current standard treatment of HCV infection with pegylated interferon plus ribavirin results in only a limited viral response. Furthermore, cumbersome pill regimens, antiretroviral related hepatotoxicity, and drug interactions of HCV and HIV regimens complicate therapy strategies. Fortunately, in the near future, new direct-acting anti-HCV agents will widen therapeutic options for HCV/HIV co-infection. Liver transplantation is also gradually accepted as a therapeutic option for end stage liver disease of HCV/HIV co-infected patients.

Prediction of hepatic fibrosis in patients coinfected with HIV and hepatitis C virus based on genetic markers

OBJECTIVE

To assess the ability of the cirrhosis risk score (CRS) to predict liver fibrosis progression in HIV/hepatitis C virus (HCV)-coinfected patients.

DESIGN

Retrospective follow-up study.

METHODS

Based on a minimum follow-up time of 10 years with HCV infection, 190 HIV/HCV-coinfected patients were classified according to their METAVIR score: (1) 25 nonprogressor patients who did not develop fibrosis (F0) and (2) 165 progressor patients who developed fibrosis (F ≥ 1). Seven polymorphisms of CRS signature and IL28B genotype were performed using the GoldenGate assay. The CRS signature was calculated by naive Bayes formula as previously described.

RESULTS

Nonprogressors had CRS values significantly lower than progressors (0.61 versus 0.67; P = 0.043). Among the progressors, we observed similar CRS values through all the fibrosis stages (F1/F2/F3/F4). The percentage of patients with CRS > 0.70 (high risk of developing fibrosis) was higher in progressors than in nonprogressors; but the percentages with values between 0.50 and 0.70 (intermediate risk) and <0.50 (low risk) were quite similar for each of the fibrosis stages (P = 0.047). The area under the receiver-operating characteristic curve of CRS for discriminating nonprogressor versus progressor was 0.625 (P = 0.043). When clinical variables were considered (age at HCV infection, intravenous drug use, gender, IL28B, and HCV genotype), the area under the receiver-operating characteristic curve of CRS improved up to 0.739 (P < 0.001).

CONCLUSIONS

CRS itself seems not to be a good marker for identifying HIV/HCV-coinfected patients who are at high risk of developing liver fibrosis. However, CRS score coupled with clinical factors might help to distinguish between nonprogressors and progressors patients.

The Korean Society for AIDS. The 2013 Clinical Guidelines for the Diagnosis and Treatment of HIV/AIDS in HIV-Infected Koreans

While a variety of clinical guidelines for the diagnosis and treatment of HIV/AIDS are used extensively around the world, the implementation of such guidelines is not assured in Korea due to constraints with respect to the diagnostic tests and antiretroviral drugs currently available in the country. Consequently, the Committee for Clinical Guidelines for the Diagnosis and Treatment of HIV/AIDS of the Korean Society for AIDS was founded in 2010, and the first edition of the Korean guidelines was published a year later. However, due to the rapid discovery of new data in the field of HIV and the evolution of the clinical environment in Korea in the last few years, it has become necessary to revise the first set of guidelines. This guideline aims to provide comprehensive information regarding the diagnosis and management of HIV/AIDS in Korea. The recommendations contain important information for physicians working with HIV/AIDS in the clinical field. A brief summary of the revised guidelines and key changes to the original version of the guidelines are summarized below.

[Consensus Statement by GeSIDA/National AIDS Plan Secretariat on antiretroviral treatment in adults infected by the human immunodeficiency virus (Updated January 2013)]

OBJECTIVE

This consensus document is an update of combined antiretroviral therapy (cART) guidelines for HIV-1 infected adult patients.

METHODS

To formulate these recommendations a panel composed of members of the GeSIDA/National AIDS Plan Secretariat (Grupo de Estudio de Sida and the Secretaría del Plan Nacional sobre el Sida) reviewed the efficacy and safety advances in clinical trials, cohort and pharmacokinetic studies published in medical journals (PubMed and Embase) or presented in medical scientific meetings. The strength of the recommendations and the evidence which support them are based on a modification of the criteria of Infectious Diseases Society of America.

RESULTS

cART is recommended in patients with symptoms of HIV infection, in pregnant women, in serodiscordant couples with high risk of transmission, in hepatitisB co-infection requiring treatment, and in HIV nephropathy. cART is recommended in asymptomatic patients if CD4 is <500cells/μl. If CD4 are >500cells/μl cART should be considered in the case of chronic hepatitisC, cirrhosis, high cardiovascular risk, plasma viral load >100.000 copies/ml, proportion of CD4 cells <14%, neurocognitive deficits, and in people aged >55years. The objective of cART is to achieve an undetectable viral load. The first cART should include 2 reverse transcriptase inhibitors (RTI) nucleoside analogs and a third drug (a non-analog RTI, a ritonavir boosted protease inhibitor, or an integrase inhibitor). The panel has consensually selected some drug combinations, for the first cART and specific criteria for cART in acute HIV infection, in tuberculosis and other HIV related opportunistic infections, for the women and in pregnancy, in hepatitisB or C co-infection, in HIV-2 infection, and in post-exposure prophylaxis.

CONCLUSIONS

These new guidelines update previous recommendations related to first cART (when to begin and what drugs should be used), how to monitor, and what to do in case of viral failure or adverse drug reactions. cART specific criteria in comorbid patients and special situations are similarly updated.

IL28B polymorphisms are associated with severity of liver disease in human immunodeficiency virus (HIV) patients coinfected with hepatitis C virus

OBJECTIVE

To evaluate the association of IL28B polymorphisms and severity of liver disease among human immunodeficiency virus (HIV)/hepatitis C virus (HCV) coinfected patients.

METHODS

We carried out a cross-sectional study on 223 patients. Liver biopsies were evaluated according to Metavir score. IL28B polymorphisms (rs12980275, rs8099917, rs7248668, and rs11881222) were genotyped using GoldenGate(®) assay.

RESULTS

IL28B polymorphisms were in strong linkage disequilibrium, especially the couples rs12980275/rs11881222 and rs8099917/rs7248668. For all patients, the rs12980275 A allele increased the odds for significant fibrosis (F ≥ 2) odds ratio (OR) = 1.68; p = 0.018) and more rapid fibrosis progression (FPR ≥ 0.075 fibrosis units/year) (OR = 1.64; p = 0.035), and decreased the odds for liver steatosis (OR = 0.61; p = 0.046). Furthermore, the rs8099917 T allele increased the odds for F ≥ 2 (OR = 1.93; p = 0.020), FPR ≥ 0.075 (OR = 2.08; p = 0.021), and elevated ALT (≥80 IU/l) (OR = 1.78; p = 0.048). For HCV-genotype 1 patients, rs12980275 A and rs8099917 T alleles decreased the odds for liver steatosis (OR = 0.22; p < 0.001 and OR = 0.39; p = 0.048; respectively). For HCV-genotype 3 patients, the rs12980275 A allele increased the odds for F ≥ 2 ((OR = 6.30; p = 0.012), FPR ≥ 0.075 (OR = 6.40; p = 0.025), and elevated ALT (OR = 4.12; p = 0.037); and the rs8099917 T allele also increased the odds for F ≥ 2 (OR = 7.56; p = 0.027), FPR ≥ 0.075 (OR = 50.8; p = 0.012), and elevated ALT (OR = 5.39; p = 0.043). However, we did not find significant trends in patients infected with HCV-genotype 4.

CONCLUSION

The major alleles of IL28B (rs12980275 A, rs11881222 A, rs8099917 T, and rs7248668 G) are associated with increased odds of liver disease severity in HIV patients infected with HCV-genotype 3. In contrast, HCV-genotype 1 patients carrying the major alleles of IL28B polymorphisms had lower odds for liver steatosis.

The treatment of chronic hepatitis C virus infection in HIV co-infection

Chronic HCV co-infection is present in up to one third of HIV-positive patients in Europe. In recent years, apart from the traditional transmission route of intravenous drug abuse, outbreaks of sexually transmitted acute HCV infections, mainly among HIV-positive men who have sex with men, have contributed to the overall disease burden.

Because the natural course of HCV infection is substantially accelerated in HIV-co-infection, end-stage liver disease has become the most frequent cause of non-AIDS related death in this population. Therefore every HIV/HCV co-infected patient should be evaluated for possible anti-HCV therapy with the goal of reaching a sustained virological response and thus cure of hepatitis C infection. The standard of care for the treatment of chronic HCV infection in HIV-infected remains a pegylated interferon in combination with weight-adapted ribavirin.

HAART should not be withheld from HCV co-infected patients due to concerns of drug related hepatotoxicity and in patients with reduced CD4-cell counts HAART should be started first. Under pegylated interferon and ribavirin combination therapy drug to drug interactions and cumulated toxicity between nucleoside analogues and anti-HCV therapy may be observed and concomitant didanosine use is contraindicated and zidovudine and stavudine should be avoided if possible.

The development of new drugs for the treatment of chronic hepatitis C represents a promising perspective also for HIV positive patients. However, these substances will probably reach clinical routine for HIV patients later than HCV monoinfected patients. Therefore at present waiting for new drugs is not an alternative to a modern pegylated interferon/ribavirin therapy.

CIHR Canadian HIV Trials Network Coinfection and Concurrent Diseases Core: Canadian guidelines for management and treatment of HIV/hepatitis C coinfection in adults

BACKGROUND

Hepatitis C virus (HCV) coinfection occurs in 20% to 30% of Canadians living with HIV, and is responsible for a heavy burden of morbidity and mortality. HIV-HCV management is more complex due to the accelerated progression of liver disease, the timing and nature of antiretroviral and HCV therapy, mental health and addictions management, socioeconomic obstacles and drug-drug interactions between new HCV direct-acting antiviral therapies and antiretroviral regimens.

OBJECTIVE

To develop national standards for the management of HCV-HIV coinfected adults in the Canadian context.

METHODS

A panel with specific clinical expertise in HIV-HCV co-infection was convened by The CIHR HIV Trials Network to review current literature, existing guidelines and protocols. Following broad solicitation for input, consensus recommendations were approved by the working group, and were characterized using a Class (benefit verses harm) and Level (strength of certainty) quality-of-evidence scale.

RESULTS

All HIV-HCV coinfected individuals should be assessed for HCV therapy. Individuals unable to initiate HCV therapy should initiate antiretroviral therapy to slow liver disease progression. Standard of care for genotype 1 is pegylated interferon and weight-based ribavirin dosing plus an HCV protease inhibitor; traditional dual therapy for 24 weeks (for genotype 2/3 with virological clearance at week 4); or 48 weeks (for genotypes 2-6). Therapy deferral for individuals with mild liver disease may be considered. HIV should not be considered a barrier to liver transplantation in coinfected patients.

DISCUSSION

Recommendations may not supersede individual clinical judgement.

Ribavirin and abacavir drug interaction in HIV-HCV coinfected patients: fact or fiction?

OBJECTIVE(S)

To examine the impact of ribavirin and abacavir coadministration on hepatitis C virus (HCV) virological response and trough ribavirin plasma concentration (Cmin) in HIV-HCV coinfected patients.

DESIGN

Pharmacokinetic substudy on patients from the ANRS CO-13 HEPAVIH cohort.

METHODS

Patients receiving ribavirin-pegylated interferon for whom a ribavirin steady state Cmin was prospectively determined were included. Rapid virological response (RVR), early virological response (EVR) and sustained virological response (SVR) as well as HCV-RNA decline were evaluated.

RESULTS

Overall, 124 HIV-HCV coinfected patients (95% on antiretroviral therapy) were enrolled. Of these patients, 22% received abacavir. The overall median (interquartile range) ribavirin Cmin was 1.6 mg/l (1.2-2.2) with no statistical difference between abacavir users and nonusers [1.5 mg/l (0.99-2.1) and 1.7 (1.2-2.3), P = 0.15]. RVR and EVR were 52 and 72%, respectively. There was no difference observed in the proportion of abacavir users vs. nonusers achieving RVR (respectively 59 vs. 50%, P = 0.40) or EVR (72 vs. 73%, P = 0.94), or in the HCV-RNA decline at week 4 [-2.24 log(10) IU/ml, (-3.58; -0.81) and -1.27 (-2.8; -0.47) P = 0.28] or at week 12 [-1.76 log(10) IU/ml (-3.67; -0.35) and -1.85 (-3.13; -1.13) (P = 0.58)]. The SVR rate was 45% for abacavir users and 24% for abacavir nonusers, but the difference was not statistically significant (P = 0.059).

CONCLUSION

In our study, there was no evidence that abacavir affected HCV treatment outcomes and the ribavirin Cmin was similar in abacavir users and nonusers, confirming the absence of pharmacokinetic interaction between abacavir and ribavirin. An abacavir-containing regimen is, therefore, a well tolerated treatment alternative for coinfected patients starting HCV treatment.

[Consensus document of Gesida and Spanish Secretariat for the National Plan on AIDS (SPNS) regarding combined antiretroviral treatment in adults infected by the human immunodeficiency virus (January 2012)]

This consensus document has been prepared by a panel consisting of members of the AIDS Study Group (Gesida) and the Spanish Secretariat for the National Plan on AIDS (SPNS) after reviewing the efficacy and safety results of clinical trials, cohort and pharmacokinetic studies published in medical journals, or presented in medical scientific meetings. Gesida has prepared an objective and structured method to prioritise combined antiretroviral treatment (cART) in naïve patients. Recommendations strength (A, B, C) and the evidence which supports them (I, II, III) are based on a modification of the Infectious Diseases Society of America criteria. The current antiretroviral treatment (ART) of choice for chronic HIV infection is the combination of three drugs. ART is recommended in patients with symptomatic HIV infection, in pregnancy, in serodiscordant couples with high transmission risk, hepatitis B fulfilling treatment criteria, and HIV nephropathy. Guidelines on ART treatment in patients with concurrent diagnosis of HIV infection and an opportunistic type C infection are included. In asymptomatic patients ART is recommended on the basis of CD4 lymphocyte counts, plasma viral load and patient co-morbidities, as follows: 1) therapy should be started in patients with CD4 counts <350 cells/μL; 2) when CD4 counts are between 350 and 500 cells/μL, therapy will be recommended and only delayed if patient is reluctant to take it, the CD4 are stabilised, and the plasma viral load is low; 3) therapy could be deferred when CD4 counts are above 500 cells/μL, but should be considered in cases of cirrhosis, chronic hepatitis C, high cardiovascular risk, plasma viral load >10(5) copies/mL, proportion of CD4 cells <14%, and in people aged >55 years. ART should include 2 reverse transcriptase inhibitors nucleoside analogues and a third drug (non-analogue reverse transcriptase inhibitor, ritonavir boosted protease inhibitor or integrase inhibitor). The panel has consensually selected and given priority to using the Gesida score for some drug combinations, some of them co-formulated. The objective of ART is to achieve an undetectable viral load. Adherence to therapy plays an essential role in maintaining antiviral response. Therapeutic options are limited after ART failures, but an undetectable viral load may be possible nowadays. Adverse events are a fading problem of ART. Guidelines in acute HIV infection, in women, in pregnancy, and to prevent mother-to-child transmission and pre- and post-exposition prophylaxis are commented upon. Management of hepatitis B or C co-infection, other co-morbidities, and the characteristics of ART in HIV-2 infection are included.

Directly acting antivirals for hepatitis C and antiretrovirals: potential for drug-drug interactions

PURPOSE OF REVIEW

Boceprevir and telaprevir are directly acting antivirals (DAAs) that have recently been licensed for treatment of hepatitis C virus (HCV) infection. Data in both untreated and previously treated patients indicate a significantly increased sustained virological response (SVR) compared with that observed with conventional therapy. However, the advent of DAA therapy poses specific challenges for HCV treatment in terms of managing drug-drug interactions (DDIs). This review aims to provide a comprehensive summary of DDI with the recently licensed DAAs, including pharmacokinetic data and current recommendations made by the manufacturers and with particular reference to antiretrovirals. Potential for DDIs with the DAAs in clinical development and the mechanisms of interaction are also discussed.

RECENT FINDINGS

Targeted pharmacokinetic drug interaction studies have demonstrated that both boceprevir and telaprevir are potent inhibitors of the metabolic enzyme cytochrome P4503A4, making them perpetrators of interactions with co-administered medications which are metabolized by this enzyme. In addition, co-administered medications may affect plasma levels of boceprevir and telaprevir via various mechanisms, some of which remain to be fully elucidated.

SUMMARY

As a result of DDIs, the concomitant use of some medicines with DAA will be contraindicated, whereas other combinations may require caution, monitoring, or dose modification of the co-administered drug. Management of DDIs with these novel agents will pose a new challenge, and prescriber awareness of the potential for DDIs is fundamental for safe prescribing. Online resources are likely to play a key role in prescriber education and clinical decision-making.

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.

Effect of accompanying antiretroviral drugs on virological response to pegylated interferon and ribavirin in patients co-infected with HIV and hepatitis C virus

OBJECTIVES

The effects of antiretroviral drugs on the response to pegylated interferon plus ribavirin remain uncertain. We evaluated whether antiretroviral drugs affected the response to pegylated interferon plus ribavirin in patients co-infected with HIV and hepatitis C virus (HCV).

METHODS

We conducted a retrospective analysis of two cohorts of HIV/HCV-co-infected patients treated with pegylated interferon plus ribavirin between 2001 and 2007 in Spain. The outcome measure was sustained virological response (SVR). Logistic regression models were used to test possible associations between non-response and pre-treatment characteristics, including accompanying antiretroviral drugs.

RESULTS

The study sample comprised 1701 patients: 63% were infected with HCV genotype (G) 1 or 4 and 88% were taking highly active antiretroviral therapy (HAART). Factors independently associated with increased odds of SVR were G2 or 3, HVC RNA <500,000 IU/mL and CDC clinical category A or B. When we adjusted for these prognostic factors and dose of ribavirin/kg, the adjusted odds ratio (AOR) of SVR for patients without HAART was 1.31 [95% confidence interval (CI) 0.91-1.88; P = 0.144]. Taking the backbone of tenofovir and lamivudine/emtricitabine as a reference, we found that, with the exception of regimens including zidovudine, the effect of other nucleoside reverse transcriptase inhibitor backbones had little effect on SVR. The AOR of SVR for zidovudine and lamivudine was 0.65 (95% CI 0.46-0.93, P = 0.017). We carried out several sensitivity analyses, the results of which were consistent with the findings of the primary analysis.

CONCLUSIONS

Our results suggest that, with the exception of regimens including zidovudine, accompanying antiretroviral drugs have little effect on the virological response to pegylated interferon plus ribavirin in HIV/HCV-co-infected patients.

Challenges and opportunities for hepatitis C drug development in HIV-hepatitis C virus-co-infected patients

The approval of the first direct-acting antivirals (DAAs) against the hepatitis C virus (HCV) has been eagerly expected for treating chronic hepatitis C in HIV individuals given that progression to cirrhosis and end-stage liver disease occurs faster in the co-infected population. The appropriate and judicious use of DAAs may provide cure to a large number of HIV-HCV patients. On the contrary, the widespread use of DAAs will occasionally be off-label or under unsatisfactory medical conditions, which may result in undesirable toxicities, drug interactions or selection of drug resistance in HCV. As a result of using first-generation DAAs in HIV-HCV-co-infected patients, a growing proportion of the remaining hepatitis C individuals will be those harboring non-HCV 1 genotypes or drug-resistant HCV variants. Over time, the largest reservoir of HCV genotype 1 patients will accumulate in resource-poor nations where access to hepatitis C therapy has been elusive and HIV treatment remains the primary health issue for the co-infected population.

Host genetics

PURPOSE OF REVIEW

To update the information on genetic markers influencing the outcome of hepatitis C virus (HCV) infection.

RECENT FINDINGS

Single-nucleotide polymorphisms (SNPs) in the region of the IL28B gene on chromosome 19, coding for the interferon (IFN)-λ3, are involved in HCV spontaneous and treatment-induced clearance, and may have an influence on liver fibrosis and inflammation in chronic carriers. The rs12979860 SNP has been recommended as single diagnostic genotype. IL28B variations are strongly associated with response to pegylated-IFN plus ribavirin (Peg-IFN/RBV) in patients with chronic infection by HCV genotype 1 or 4. Thus, the rs12979860 CC genotype is associated with a two-fold increase in the sustained virological response (SVR) rate in this setting. SVR is less influenced by IL28B variants in HCV genotype 2 or 3 carriers. The rs12979860 CC genotype frequencies vary among diverse genetic ancestor groups, explaining partly the differences in SVR among them. The underlying mechanisms are unclear, but it may involve the expression of IFN-stimulated genes in the liver. Inosine triphosphatase genotype is predictive of RBV-induced anemia, but its clinical usefulness is less straightforward than that of IL28B SNPs.

SUMMARY

IL28B genotyping can aid in Peg-IFN/RBV clinical decision-making, and it may be useful in the selection of candidates for triple therapy with Peg-IFN/RBV plus direct-acting antiviral drugs.

[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.

Effect of an induction period of pegylated interferon-α2a and ribavirin on early virological response in HIV-HCV-coinfected patients: results from the CORAL-2 study

BACKGROUND

It is uncertain whether a 4-week induction period of pegylated interferon and ribavirin increases early virological response (EVR) in HIV-HCV-coinfected patients.

METHODS

HIV and HCV genotype 1- and 4-coinfected subjects were randomized to receive pegylated interferon-α2a 270 μg/week plus ribavirin 1,600 mg daily and epoetin-β for 4 weeks, followed by pegylated interferon-α2a at standard dosages plus weight-based ribavirin (WBR) dosage for 8 weeks (induction arm [IA]), or pegylated interferon-α2a plus WBR for 12 weeks (standard therapy arm [SA]). HCV RNA was determined at weeks 0, 1, 2, 3, 4, 8 and 12. Ribavirin plasma trough concentrations were determined at weeks 4 (RBV-C(4)) and 12 (RBV-C(12)).

RESULTS

A total of 67 patients were included; 33 in the SA and 34 in the IA. Overall, 25% received nucleoside reverse transcriptase inhibitor (NRTI)-sparing regimens. More patients achieved an HCV RNA decrease ≥1 log(10) at week 4 in the IA than in the SA (62% versus 38%; P=0.017), but EVR rates were similar in the two groups (74% versus 59% in the IA and SA, respectively; P=0.15). Independent predictors of faster HCV RNA decrease at 12 weeks were higher RBV-C(4) and younger age. RBV-C(4) were higher in patients allocated in the IA and in those receiving NRTIs (P=0.039).

CONCLUSIONS

A 4-week induction with pegylated interferon-α2a plus ribavirin was associated with a greater decrease in HCV RNA at week 4; however, this did not translate into higher EVR rates. Higher RBV doses and avoidance of NRTI-sparing antiretroviral regimens might improve HCV treatment efficacy.

Interferon combination therapy for HIV/hepatitis C virus coinfection

IFN-α has been the cornerstone of chronic hepatitis C virus (HCV) treatment for over a decade. Yet, rates of sustained virologic response of HCV infection to interferon-based therapy, particularly in difficult-to-treat populations, have been disappointingly low. This is particularly true in HIV/HCV coinfection, in which less than a third of patients typically respond to therapy. New HCV protease inhibitors, most of which will need to be administered with pegylated interferon, are in development, but comprehensive, long-term data for their use in coinfected patients is not yet available. Understanding the basis of this population's poor response to interferon-based therapy is crucial to future exploration of new therapeutic options, immunotherapy and prognosis in HIV/HCV-coinfected population.

[Coinfection with HIV and HCV: abacavir and ribavirine, why not?]

A 48-year old male coinfected by human immunodeficiency virus and hepatitis C virus (HCV) genotype 3a. The patient was under clinically and virologically effective treatment with Trizivir (zidovudine, lamivudine and abacavir) when it was decided to initiate treatment for the chronic HCV infection with peginterferon and ribavirin. Should the ongoing antiretroviral treatment be adjusted?

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.

Liver transplantation in human immunodeficiency virus-positive patients

With the successful introduction of combined antiretroviral therapy (cART), human immunodeficiency virus (HIV) is now regarded as a chronic illness with excellent long-term outcomes. However, chronic exposure to viral etiologies (ie, chronic hepatitis B and hepatitis C) and drug-induced toxicity secondary to cART have resulted in increasing rates of mortality and morbidity due to end-stage liver disease. HIV disease is no longer considered an absolute contraindication to liver transplantation (LT) by most transplant centers worldwide. Because the burden of liver disease in this cohort is likely to increase, this review addresses the key etiologies and the management strategies available for HIV-positive patients undergoing LT.

The influence of HAART on the efficacy and safety of pegylated interferon and ribavirin therapy for the treatment of chronic HCV infection in HIV-positive Individuals

Objective

This study was performed to investigate the impact of HAART versus no HAART and nucleoside free versus nucleoside containing HAART on the efficacy and safety of pegylated interferon and ribavirin therapy for the treatment of chronic HCV infection in HIV/HCV co-infected patients. In addition a control group of HCV mono-infected patients undergoing anti-HCV therapy was evaluated.

Methods

Multicenter, partially randomized, controlled clinical trial. HIV-negative and -positive patients with chronic HCV infection were treated with pegylated interferon alfa-2a and ribavirin (800 - 1200 mg/day) for 24 - 48 weeks in one of four treatment arms: HIV-negative (A), HIV-positive without HAART (B) and HIV-positive on HAART (C). Patients within arm C were randomized to receive open label either a nucleoside containing (C1) or a nucleoside free HAART (C2).

Results

168 patients were available for analysis. By intent-to-treat analysis similar sustained virological response rates (SVR, negative HCV-RNA 24 weeks after the end of therapy) were observed comparing HIV-negative and -positive patients (54% vs. 54%, p = 1.000). Among HIV-positive patients SVR rates were similar between patients off and on HAART (57% vs. 52%, p = 0.708). Higher SVR rates were observed in patients on a nucleoside free HAART compared to patients on a nucleoside containing HAART, though confounding could not be ruled out and in the intent-to-treat analysis the difference was not statistically significant (64% vs. 46%, p = 0.209).

Conclusions

Similar response rates for HCV therapy can be achieved in HIV-positive and -negative patients. Patients on nucleoside free HAART reached at least equal rates of sustained virological response compared to patients on standard HAART.

[AIDS Study Group/Spanish AIDS Plan consensus document on antiretroviral therapy in adults with human immunodeficiency virus infection (updated January 2010)]

OBJECTIVE

This consensus document is an update of antiretroviral therapy recommendations for adult patients with human immunodeficiency virus infection.

METHODS

To formulate these recommendations a panel made up of members of the Grupo de Estudio de Sida (Gesida, AIDS Study Group) and the Plan Nacional sobre el Sida (PNS, Spanish AIDS Plan) reviewed the advances in the current understanding of the pathophysiology of human immunodeficiency virus (HIV) infection, the efficacy and safety of clinical trials, and cohort and pharmacokinetic studies published in biomedical journals or presented at scientific meetings. Three levels of evidence were defined according to the data source: randomized studies (level A), cohort or case-control studies (level B), and expert opinion (level C). The decision to recommend, consider or not to recommend ART was established in each situation.

RESULTS

Currently, the treatment of choice for chronic HIV infection is the combination of three drugs of two different classes, including 2 nucleosides or nucleotide analogs (NRTI) plus 1 non-nucleoside (NNRTI) or 1 boosted protease inhibitor (PI/r), but other combinations are possible. Initiation of ART is recommended in patients with symptomatic HIV infection. In asymptomatic patients, initiation of ART is recommended on the basis of CD4 lymphocyte counts, plasma viral load and patient co-morbidities, as follows: 1) therapy should be started in patients with CD4 counts below 350 cells/microl; 2) When CD4 counts are between 350 and 500 cells/microl, therapy should be started in case of cirrhosis, chronic hepatitis C, high cardiovascular risk, HIV nephropathy, HIV viral load above 100,000 copies/ml, proportion of CD4 cells under 14%, and in people aged over 55; 3) Therapy should be deferred when CD4 are above 500 cells/microl, but could be considered if any of previous considerations concurs. Treatment should be initiated in case of hepatitis B requiring treatment and should be considered for reduce sexual transmission. The objective of ART is to achieve an undetectable viral load. Adherence to therapy plays an essential role in maintaining antiviral response. Therapeutic options are limited after ART failures but undetectable viral loads maybe possible with the new drugs even in highly drug experienced patients. Genotype studies are useful in these situations. Drug toxicity of ART therapy is losing importance as benefits exceed adverse effects. Criteria for antiretroviral treatment in acute infection, pregnancy and post-exposure prophylaxis are mentioned as well as the management of HIV co-infection with hepatitis B or C.

CONCLUSIONS

CD4 cells counts, viral load and patient co-morbidities are the most important reference factors to consider when initiating ART in asymptomatic patients. The large number of available drugs, the increased sensitivity of tests to monitor viral load, and the ability to determine viral resistance is leading to a more individualized therapy approach in order to achieve undetectable viral load under any circumstances.

The influence of abacavir and other antiretroviral agents on virological response to HCV therapy among antiretroviral-treated HIV-infected patients

BACKGROUND

It remains unclear if certain antiretroviral medications, particularly abacavir, compromise response to HCV therapy. Such data could inform the selection of appropriate antiretrovirals in HIV/HCV-coinfected patients. The aim of this study was to determine if use of abacavir, as well as other antiretrovirals, was associated with reduced response to pegylated interferon (PEG-IFN) plus ribavirin.

METHODS

A cohort study was performed among antiretroviral-treated HIV/HCV-coinfected patients initiating PEG-IFN plus ribavirin between January 2001 and June 2007 at six sites in the United States. Abacavir and other antiretrovirals represented exposures of interest. Study outcomes included an early virological response (> or =2 log IU/ml decrease in HCV viral load at 12 weeks) and sustained virological response (undetectable HCV viral load 24 weeks after treatment discontinuation).

RESULTS

Among 212 patients, 74 (35%) received abacavir. For patients infected with HCV genotype 1 or 4, no differences were observed between abacavir users and non-users in early virological response (26 [40%] versus 53 [44%]; adjusted odds ratio [OR] 1.00; 95% confidence interval [CI] 0.50-2.00) or sustained virological response (8 [13%] versus 13 [12%]; adjusted OR 1.34; 95% CI 0.50-3.62). Among genotype 2 and 3 patients, rates of early virological response (7 [78%] versus 16 [89%]; OR 0.44; 95% CI 0.05-3.76) and sustained virological response (3 [33%] versus 8 [44%]; OR 0.63; 95% CI 0.12-3.32) were also similar between abacavir users and non-users. No association was found between other antiretrovirals and a lack of early or sustained response.

CONCLUSIONS

Use of abacavir or other antiretroviral medications was not associated with reduced early or sustained virological response rates.

Ability of treatment week 12 viral response to predict long-term outcome in genotype 1 hepatitis C virus/HIV coinfected patients

OBJECTIVE

Guidelines recommendation to extend treatment duration in genotype 1 hepatitis C virus (HCV)/HIV-coinfected patients who clear the virus later than treatment week 4 is not evidence-based. Our main objective was to study the ability of week 12 viral response [early virologic response (EVR)] to predict long-term outcome in patients treated for 48 weeks.

DESIGN

Multicenter retrospective cohort analysis.

METHODS

Genotype 1 HCV treatment-naive, HIV-coinfected adult patients with compensated liver disease who started combination therapy with fixed-dose pegylated-interferon (pegIFN) alfa-2a or weight-based pegIFN alfa-2b plus ribavirin were included. Univariate and forward stepwise logistic regression analysis were used to identify predictors of sustained viral response (SVR) and relapse.

RESULTS

By intention-to-treat analysis, 31.3% (87/278) of patients achieved an SVR. SVR rate was more than three-fold higher in patients who cleared the virus by week 12 of treatment compared with late responders. Among 123 end-of-treatment responders, 36 (29.3%) relapsed. Relapse risk increased in patients with cirrhosis, in those with ribavirin dose reductions and in late responders: more than 65% of patients who cleared the virus between weeks 12 and 24 relapsed following 48 weeks of treatment compared with 10% of those attaining a complete EVR (<15 IU/ml) at treatment week 12 (risk ratio 6.4, 95% confidence interval 2.9-14.4).

CONCLUSION

Viral response at treatment week 12 is a strong predictor of long-term outcome. Genotype 1 HCV/HIV-coinfected patients who achieve a complete EVR (<15 IU/ml) are at low risk of viral relapse after completing the standard 48 weeks of therapy.

HIV/HCV-coinfection: which role can new antiretrovirals such as integrase inhibitors play?

End-stage liver disease has become one of the most frequent causes of death in HIV/HCV-coinfected patients. The role of new antiretrovirals in the progression of liver fibrosis has yet to be defined. However with significant toxicities and drug-to-drug interactions of nucleoside reverse transcriptase inhibitors in combination with ribavirin, with drug to drug interaction of HIV protease inhibitors with HCV protease inhibitors and calcineurin-inhibitors, new antiretrovirals lacking these interactions represent attractive alternatives in the setting of anti-HCV therapy or post liver transplantation. In the following review we want to focus on the new class of HIV integrase inhibitors and discuss present data with regard to special issues of HIV and HCV co-infection.

HCV drug discovery aimed at viral eradication

Hepatitis C virus (HCV) causes significant morbidity and mortality worldwide with nearly 3% of the world population infected by this virus. Fortunately, this virus does not establish latency, and hence it may be possible to eradicate it. HCV is strongly associated with liver cirrhosis and hepatocellular carcinoma and is currently treated with pegylated interferon-alpha (peg-IFN-alpha) and ribavirin. Unfortunately, these limited treatment options often produce significant side effects, and currently, complete eradication of virus with combined drug modalities has not yet been achieved for the majority of chronically HCV-infected individuals. Restricted treatment options, lack of a universal cure for HCV and the link between chronic infection, liver cirrhosis and hepatocellular carcinoma necessitate design of novel drugs and treatment options. Understanding the relationship between the immune response, viral clearance and inhibition of viral replication with pharmacology-based design can ultimately allow for complete eradication of HCV. This review focuses upon significant novel preclinical and clinical specifically targeted antiviral therapy (STAT-C) drugs under development, highlights their mechanism of action, and discusses their impact on systemic viral loads and permanent clearance of infection.

[Treatment of chronic hepatitis C in HIV-infected patients]

Since the pivotal trials conducted over the last few years which have used the combination of pegylated interferon along with fixed low doses (800 mg/day) of ribavirin and have provided treatment for 12 months, regardless the kinetics of hepatitis C virus (HCV) viral load during therapy, great progress has been made in the treatment of chronic hepatitis C in HIV-infected patients. Results approaching those seen in HCV-monoinfected patients can be obtained with optimal dosages of ribavirin, extension of treatment beyond 48 weeks in the absence of rapid virologic response and/or in patients older than 40 years, with severe fibrosis (METAVIR score F3 or F4) and/or with high HCV viral load and with a better management of HIV treatment in order to avoid a negative interaction between HCV and HIV therapies (interaction between abacavir and ribavirin) and to improve the tolerance of HCV therapy (Didanosine should never be used with ribavirin, Zidovudine and Stavudine should be avoided when possible with ribavirin).

Plasma ribavirin trough concentrations at week 4 predict hepatitis C virus (HCV) relapse in HIV-HCV-coinfected patients treated for chronic hepatitis C

The influence of ribavirin trough concentrations (RBV C(trough)) on the risk of hepatitis C virus (HCV) relapse was retrospectively analyzed in 99 HIV-HCV-coinfected patients who achieved end-of-treatment response with pegylated alpha interferon plus weight-based RBV. The independent predictors (odds ratio [OR] [95% confidence interval (CI)]) of HCV relapse were RBV plasma C(trough) of <2.5 microg/ml (4.5 [1.3 to 15.5]), baseline serum HCV RNA (2.5 [1.2 to 5.1]), and HCV genotype 1 or 4 (13.3 [2.6 to 66.7]). Monitoring of RBV C(trough) may permit early adjustment of RBV dosage to avoid HCV relapse.

Understanding and managing the adverse effects of antiretroviral therapy

Highly active antiretroviral therapy (HAART) has changed the landscape of HIV disease in a way that seemed unthinkable a decade ago; from an almost uniformly fatal disease to a chronic manageable one. The first HAART regimens worked in suppressing virus, but were encumbered by a variety of short term and long term side effects. More recent regimens became simpler, easier to take, and with fewer adverse events. As we look to people living perhaps a normal life span with HIV, the increasing number of antiretroviral agents available means that individualizing treatment has become more feasible and the longer downstream adverse events related to HAART, such as its effect on cardiovascular disease and diabetes, renal and hepatic disease, have begun to dominate our choice of drugs. A knowledge of both the short and long term adverse events associated with HAART is essential for providers and for patients. For new drugs to be acceptable in the current field, they will have to pass a litmus test of tolerability. Since adverse events are often remarkably idiosyncratic, pharmacogenomics may offer a way of predicting side effects and their severity from a particular drug or drug class in individual patients. 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.

Insulin resistance is not a relevant predictor of sustained virological response to pegylated interferon plus ribavirin in HIV/HCV co-infected patients

BACKGROUND/AIMS

To evaluate the possible influence of baseline insulin resistance in sustained virological response.

METHODS

One hundred and fifty-five consecutive individuals from a multicentric cohort of HIV/HCV co-infected patients who underwent therapy with pegylated interferon plus ribavirin were included. The main outcome variable was sustained virological response, defined as undetectable plasma HCV RNA at week 24 after the end of the therapy. Insulin resistance was determined using the HOMA method.

RESULTS

Sustained virological response was achieved in 55 (36%) patients. Forty-two (38%) patients with a HOMA lower than 4 developed sustained virological response vs 13 (29%) of those with a HOMA above 4 (p=0.27). Analyses restricted to patients harbouring genotype 1 or 4 showed similar rates of sustained virological response among patients with a HOMA below and above 4 [19 (27%) vs 7 (24%); p=0.8]. In the multivariate analysis, genotype 3 [AOR 9.26; 95% CI 3.03-28.30; p<0.0001], a baseline HCV viral load below 600.000IU/mL [AOR 2.97; 95% CI 1.03-8.57; p=0.04] and baseline LDL cholesterol above 100mg/dL [AOR 6.62; 95% CI 1.97-22.19; p=0.002] were independently associated with sustained virological response.

CONCLUSIONS

Insulin resistance is not a relevant predictor of sustained virological response to pegylated interferon plus ribavirin in HIV/HCV co-infected patients.

Co-infections and co-therapies: treatment of HIV in the presence of hepatitis C and hepatitis B

An increasing number of people are chronically infected with HIV and HCV, and/or HBV owing to shared routes of transmission. With the advent of HAART, liver disease secondary to hepatitis co-infections has emerged as a leading cause of morbidity and mortality in HIV-infected persons. There is increasing need to manage dual infection, but treatment is complicated by co-morbidities, overlapping toxicities, drug activities and resistance. A model of treatment that builds on the lessons learned from the treatment of HIV has evolved to maximize success of treating dual infections. This review will address current strategies for the management of HIV in the setting of HCV and HBV co-infection and discuss future treatment directions and challenges.

Abacavir does not Influence the Rate of Virological Response in HIV–HCV-Coinfected Patients Treated with Pegylated Interferon and Weight-Adjusted Ribavirin

Background

The combination of pegylated interferon (PEG-IFN) plus ribavirin (RBV) is the standard of care for hepatitis C virus (HCV) treatment in HIV-coinfected individuals. In 2007, abacavir (ABC)-based antiretroviral therapy was, for the first time, reported to be associated with early virological failure during HCV treatment. The aim of our study was to evaluate the effect of ABC on the response rate to HCV therapy.

Methods

A retrospective analysis of HIV–HCV- coinfected patients treated with PEG-IFN and weight-adjusted RBV in four hospitals in Spain was performed. An analysis of baseline descriptive variables was conducted. Logistic regression models were used to test possible associations between non-response and pretreatment characteristics, including antiretroviral drugs.

Results

A total of 244 HIV–HCV-coinfected patients treated with PEG-IFN and RBV were included. Overall, 85% of patients were on highly active antiretroviral therapy; of these patients, 24% received ABC-based regimens. The most frequent genotypes were 1 and 3. RBV dosing was ≥13.2 mg/kg/day in 97% of the patients. In the global intent-to-treat analyses, 46.3% of patients reached a sustained virological response (SVR; 46.2% in ABC group versus 46.7% in non-ABC group, P=1). The only two factors in the multivariate analysis that were statistically associated with an increased risk of failure to achieve SVR were HCV genotypes 1 or 4 and older age. The use of ABC was not associated with failure to achieve SVR at any of the other time points evaluated.

Conclusions

Our data suggest that the use of ABC-based regimens in the context of HCV therapy does not negatively affect the outcome of this treatment.