Interferon-ribavirin in association with stavudine has no impact on plasma human immunodeficiency virus (HIV) type 1 level in patients coinfected with HIV and hepatitis C virus: a CORIST-ANRS HC1 trial

The determination of human peripheral blood mononuclear cell counts using a genomic DNA standard and application in tenofovir diphosphate quantitation

A fluorescent quantitation method to determine PBMC-derived DNA amounts using purified human genomic DNA (gDNA) as the reference standard was developed and validated. gDNA was measured in a fluorescence-based assay using a DNA intercalant, SYBR green. The fluorescence signal was proportional to the amount (mass) of DNA in the sample. The results confirmed a linear fit from 0.0665 to 1.17 μg/μL for gDNA, corresponding to 2.0 × 10⁶ to 35.0 × 10⁶ cells/PBMC sample. Intra-batch and inter-batch accuracy (%RE) was within ±15%, and precision (%CV) was <15%. Benchtop stability, freeze/thaw stability and long term storage stability of gDNA in QC sample matrix, PBMC pellets samples, and pellet debris samples, respectively, as well as dilution linearity had been established. Consistency between hemocytometry cell counting method and gDNA-based counting method was established. 6 out of 6 evaluated PBMC lots had hemocytometry cell counts that were within ±20% of the cell counts determined by the gDNA method. This method was used in conjunction with a validated LC-MS/MS method to determine the level of tenofovir diphosphate (TFV-DP), the active intracellular metabolite of the prodrugs tenofovir alafenamide (TAF) and tenofovir disoproxil fumarate (TDF), measured in PBMCs in clinical trials of TAF or TDF-containing fixed dose combinations.

Intracellular Tenofovir and Emtricitabine Anabolites in Genital, Rectal, and Blood Compartments from First Dose to Steady State

The pharmacokinetics (PK) of tenofovir-diphosphate (TFV-DP) and emtricitabine-triphosphate (FTC-TP), the active anabolites of tenofovir disoproxil fumarate (TDF), and emtricitabine (FTC) in blood, genital, and rectal compartments was determined in HIV-positive and seronegative adults who undertook a 60-day intensive PK study of daily TDF/FTC (plus efavirenz in HIV positives). Lymphocyte cell sorting, genital, and rectal sampling occurred once per subject, at staggered visits. Among 19 HIV-positive (3 female) and 21 seronegative (10 female) adults, TFV-DP in peripheral blood mononuclear cells (PBMC) accumulated 8.6-fold [95% confidence interval (CI): 7.2-10] from first-dose to steady-state concentration (Css) versus 1.7-fold (95% CI: 1.5-1.9) for FTC-TP. Css was reached in ∼11 and 3 days, respectively. Css values were similar between HIV-negative and HIV-positive individuals. Css TFV-DP in rectal mononuclear cells (1,450 fmol/10⁶ cells, 898-2,340) was achieved in 5 days and was >10 times higher than PBMC (95 fmol/10⁶ cells, 85-106), seminal cells (22 fmol/10⁶ cells, 6-79), and cervical cells (111 fmol/10⁶ cells, 64-194). FTC-TP Css was highest in PBMC (5.7 pmol/10⁶ cells, 5.2-6.1) and cervical cells (7 pmol/10⁶ cells, 2-19) versus rectal (0.8 pmol/10⁶ cells, 0.6-1.1) and seminal cells (0.3 pmol/10⁶ cells, 0.2-0.5). Genital drug concentrations on days 1-7 overlapped with estimated Css, but accumulation characteristics were based on limited data. TFV-DP and FTC-TP in cell sorted samples were highest and achieved most rapidly in CD14⁺ compared with CD4⁺, CD8⁺, and CD19⁺ cells. Together, these findings demonstrate cell-type and tissue-dependent cellular pharmacology, preferential accumulation of TFV-DP in rectal mononuclear cells, and rapid distribution into rectal and genital compartments.

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.

Protein versus DNA as a marker for peripheral blood mononuclear cell counting

Quantitative analysis of intracellular analytes requires an accurate and precise assay not only for the quantitation of the analytes, but also for the quantitation of the number of cells in which they were determined. In this technical note we compare protein and DNA as markers for the number of peripheral blood mononuclear cells (PBMCs) isolated from whole blood. The protein content of samples was highly influenced by red blood cell contamination and was, therefore, a less suitable marker. The DNA-based method was unaffected by red blood cell contamination and was finally validated over a range from 10 × 10⁶ to 300 × 10⁶ PBMCs/mL.

Figure

Nanomedicines in the treatment of patients with hepatitis C co-infected with HIV--focus on pegylated interferon-alpha

In immuno-competent individuals, the natural course of chronic hepatitis C virus (HCV) infection is highly variable and 5%–30% of patients develop cirrhosis over 20 years. Co-infection with HCV and human immunodeficiency virus (HIV) is an important prognostic factor and associated with more frequent and accelerated progression to cirrhosis. Until recently HIV/AIDS-related complications were life limiting in patients co-infected with HCV; the introduction of highly active antiretroviral treatment (HAART) and the better prognosis of HIV infection has made HCV-related complications an emerging health problem in HCV/HIV co-infected individuals. Treatment of chronic HCV infection has also evolved since the introduction of interferon-alpha. Recently, introduction of pegylated interferon-alpha (peginterferon-alpha) has resulted in an increase in sustained virus clearance rates of up to 80% in selected genotypes and patient populations. The safety and efficacy of modern anti HCV treatment regimens – based on peginterferon-alpha in combination with ribavirin – was evaluated in 4 controlled trials. Sustained clearance of hepatitis C virus can be achieved in up to 35% of patients with HIV/HCV co-infection, and novel HCV treatment regimens based on peginterferon-alpha have no negative effect on the control of HIV disease. In conclusion, if HIV infection is well controlled and CD4⁺ cell counts >100/mm³, treatment of chronic hepatitis C with peginterferon in combination with ribavirin is safe and should be given for 48 weeks regardless of the HCV genotype. Introduction of peginterferon-alpha has significantly improved adherence to treatment and treatment efficacy; in particular sustained virologic response in patients with HCV genotype 1 or 4 infection improved, but sustained viral clearance in only 7%–38% of patients infected with genotype 1 and 4 cannot be the final step in development of effective treatments in patients with HCV/HIV co-infection.

Therapeutic issues in HIV/HCV-coinfected patients

The importance of treating hepatitis C virus (HCV)-associated morbidities in a growing population of patients coinfected with human immunodeficiency virus (HIV) has increased since the introduction of highly active antiretroviral therapy. As a result, investigative attention is turning to HCV-related liver disease and treatment-associated issues in coinfection. HIV/HCV-coinfected patients have higher HCV RNA loads and show more rapid progression of fibrosis than do monoinfected patients. Combination therapy with pegylated interferon plus ribavirin (RBV) is the standard of care for HCV in coinfected patients. Therapy slows fibrosis progression, but toxicity prevents identification of the most effective RBV dose. Coinfected patients have about a threefold greater risk of antiretroviral therapy-associated hepatotoxicity than patients with HIV only. Other challenges include anaemia, mitochondrial toxicity, drug-drug interactions and leucopenia. Thus, chronic hepatitis C should be treated in HIV/HCV-coinfected patients, but steps must be taken to prevent and treat potential toxicities. The first European Consensus Conference on the Treatment of Chronic Hepatitis B and C in HIV Co-infected Patients was held March 2005 in Paris to address these issues. This article reviews the peer-reviewed literature and expert opinion published from 1990 to 2005, and compares results with presentations and recommendations from the Consensus Conference to best present current issues in coinfection.

Antiviral hepatitis and antiretroviral drug interactions

More and more HIV-infected patients are treated for viral hepatitis, increasing interactions. HEPATITIS C: The concomitant use of didanosine and ribavirin increases the risk of mitochondrial toxicity, responsible for pancreatitis and/or lactic acidosis. Lactic acidosis is characterized by a high mortality rate. Thus, didanosine, but also stavudine, should not be co-administered with ribavirin. Cases of hepatic decompensation have been reported in cirrhotics concomitantly receiving ribavirin and didanosine. Thus, this co-admininistration should be contraindicated in patients with advanced liver fibrosis. Anemia is a frequent side effect of ribavirin. In patients with zidovudine-related anemia, this drug should be discontinued before prescribing ribavirin. Erythropoietin may help to improve the haemoglobin level. HEPATITIS B: Adefovir significantly decreases the plasma levels of saquinavir. Pancreatitis may occur with the co-administration of didanosine and tenofovir. Thus this co-administration should be avoided. Atazanavir concentrations are decreased when tenofovir is co-administered. Thus, atazanavir should be boosted with ritonavir, when combined with tenofovir. Atazanavir increases the concentrations of tenofovir, with the potential risk of increasing the adverse events of tenofovir, including renal disorders. Tenofovir area under the curve is increased if lopinavir-ritonavir are co-administered. The main interactions, with a fatal risk, are observed with didanosine, when co-administered with ribavirin (hepatitis C) or with tenofovir (hepatitis B). Anemia is frequent, but usually moderate, when zidovudine is co-administered with ribavirin. Other interactions are usually easy to manage.

Eligibility for and Outcome of Hepatitis C Treatment of HIV-Coinfected Individuals in Clinical Practice: The Swiss HIV Cohort Study

Background

Morbidity and mortality of individuals co-infected with HIV and hepatitis C virus (HCV) is often determined by the course of their HCV infection. Only a selected proportion of those in need of HCV treatment are studied in randomized controlled trials (RCTs). We analysed the prevalence of HCV infection in a large cohort, the number of individuals requiring treatment, the eligibility for HCV treatment, and the outcome of the combination therapy with pegylated interferon-α and ribavirin in routine practice.

Methods

We analysed prescription patterns of HCV treatment and treatment outcomes among participants from the Swiss HIV Cohort Study with detectable hepatitis C viraemia (between January 2001 and October 2004). Efficacy was measured by the number of patients with undetectable HCV RNA at the end of therapy (EOTR) and at 6 months after treatment termination (SVR). Intention-to-continue-treatment principles were used.

Results

A total of 2,150 of 7,048 (30.5%) participants were coinfected with HCV; HCV RNA was detected in 60%, and not assessed in 26% of HCV-antibody-positive individuals. One hundred and sixty (12.5%) of HCV-RNA-positive patients started treatment. In patients infected with HCV genotypes 1/4 or 2/3, EOTR was achieved in 43.3% and 81.2% of patients, respectively, and SVR rates were 28.4% and 51.8%, respectively. More than 50% of the HCV-treated patients would have been excluded from two large published RCTs due to demographic, clinical and laboratory criteria.

Conclusions

Despite clinical and psychosocial obstacles encountered in clinical practice, HCV treatment in HIV-coinfected individuals is feasible with results similar to those obtained in RCTs.

Effect of ribavirin on intracellular and plasma pharmacokinetics of nucleoside reverse transcriptase inhibitors in patients with human immunodeficiency virus-hepatitis C virus coinfection: results of a randomized clinical study

The intracellular triphosphorylation and plasma pharmacokinetics of lamivudine (3TC), stavudine (d4T), and zidovudine (ZDV) were assessed in a pharmacokinetic substudy, in 56 human immunodeficiency virus-hepatitis C virus (HIV-HCV) coinfected patients receiving peginterferon alfa-2a (40KD) 180 microg/week plus either placebo or ribavirin (RBV) 800 mg/day in the AIDS PEGASYS Ribavirin International Coinfection Trial. There were no significant differences between patients treated with RBV and placebo in plasma pharmacokinetics parameters for the nucleoside reverse transcriptase inhibitors (NRTIs) at steady state (weeks 8 to 12): ratios of least squares mean of area under the plasma concentration-time curve (AUC(0-12 h)) were 1.17 (95% confidence interval, 0.91 to 1.51) for 3TC, 1.44 (95% confidence interval, 0.58 to 3.60) for d4T and 0.85 (95% confidence interval, 0.50 to 1.45) for ZDV, and ratios of least squares mean plasma C(max) were 1.33 (95% confidence interval, 0.99 to 1.78), 1.06 (95% confidence interval, 0.68 to 1.65), and 0.84 (95% confidence interval, 0.46 to 1.53), respectively. Concentrations of NRTI triphosphate (TP) metabolites in relation to those of the triphosphates of endogenous deoxythymidine-triphosphate (dTTP) and deoxcytidine-triphosphate (dCTP) were similar in the RBV and placebo groups. Differences (RBV to placebo) in least squares mean ratios of AUC(0-12 h) at steady state were 0.274 (95% confidence interval, -0.37 to 0.91) for 3TC-TP:dCTP, 0.009 (95% confidence interval, -0.06 to 0.08) for d4T-TP:dTTP, and -0.081 (95% confidence interval, -0.40 to 0.24) for ZDV-TP:dTTP. RBV did not adversely affect HIV-1 replication. In summary, RBV 800 mg/day administered in combination with peginterferon alfa-2a (40KD) does not significantly affect the intracellular phosphorylation or plasma pharmacokinetics of 3TC, d4T, and ZDV in HIV-HCV-coinfected patients.

Measurement of intracellular didanosine and tenofovir phosphorylated metabolites and possible interaction of the two drugs in human immunodeficiency virus-infected patients

Recent work has demonstrated the existence of a systemic interaction between didanosine (ddI) and tenofovir disoproxyl fumarate (TDF) that leads to a significant increase in plasma ddI levels when coadministered with TDF (40 to 50% increase). These two drugs are, respectively, nucleoside and nucleotide analogues of adenosine and efficiently inhibit the human immunodeficiency virus (HIV) reverse transcriptase when transformed to their triphosphate moieties in the intracellular (IC) medium (ddA-TP and TFV-DP, respectively). Since ddI and TDF partly share the same IC metabolic pathway leading to the active triphosphates, we investigated a putative IC interaction. We used high-performance liquid chromatography-tandem mass spectrometry techniques to determine ddA-TP and TFV-DP IC levels in HIV-infected patients cotreated with both drugs, in comparison with patients treated with just one of the two drugs. These measurements revealed no significant differences in IC levels of the corresponding triphosphates when ddI (250 mg, once a day [QD]) was coadministered with TDF (300 mg, QD) compared to ddI 400 mg (QD) administered without TDF, thus supporting the dose adaptation proposed for this combination. However, we observed that both ddA-TP and TFV-DP have very long IC half-lives, resulting in unusual IC pharmacokinetic profiles with no significant changes in triphosphate concentrations between two dosings. In the case of TFV-DP, this t(1/2) of elimination was roughly estimated to be 180 h (7.5 days). This characteristic is certainly interesting in terms of efficacy but could have some drawbacks in terms of virus resistance for patients discontinuing these drugs.

Delivering Therapy for Hepatitis C Virus Infection to Incarcerated HIV-Seropositive Patients

The increase in morbidity and mortality due to end-stage liver disease has fueled recent guidelines that recommend consideration of treatment for hepatitis C in human immunodeficiency virus (HIV)-infected patients. Unfortunately, studies indicate that few patients coinfected with HIV and hepatitis C virus (HCV) are treated for their underlying hepatitis because of ongoing substance abuse, depression, chaotic lifestyles, homelessness, and perceived nonadherence. The structured environment of the prison system enables clinicians to provide complicated therapies for HCV to HIV-infected patients in combination with substance abuse programs. Furthermore, adherence to and adverse effects of therapy can be closely monitored. Offering treatment for HCV infection during incarceration to HIV-seropositive persons is highly efficient and targets underserved minority patients who have limited access to care in the community.

Efficacité et tolérance de l'association interféron pégylé-ribavirine chez les patients co-infectés VIH-VHC en pratique clinique : étude observationnelle de 32 patients

OBJECTIVE

To describe efficacy and safety in clinical practice of pegylated interferon plus ribavirin (INFpeg-Riba) in the treatment of hepatitis C viral infection (HCV) in HIV infected patients.

METHODS

Monocentric retrospective study with inclusion of all patients who received at least once INFpeg-Riba before April 1st 2003. All patients were followed up to six months after the end of HCV therapy.

RESULTS

Thirty two HIV-positive patients (23 men and 9 women) with chronic hepatitis C treated by INFpeg-Riba were included. The mean age was 43 years. Fourteen patients carried HCV genotype 2 or 3 (43 %) and 18 patients carried genotype 1 or 4 (57%). The Metavir score of fibrosis showed fibrosis F1 (N =3), F2 (N =14), F3 (N =7) and F4 - cirrhosis (N =8). Twenty six patients (81%) were naive for anti hepatitis C drugs. Thirty one per cent of patients were at AIDS stage and 84% were receiving antiretroviral drugs. The mean CD4 cell count was 469 /ml and the plasma RNA HIV was less than 50 copies /ml in 57% of the cases. Adverse events leading to reduction of dose of drugs occurred in 40% and adverse events leading to discontinuation treatment occurred in 12%. A decline of CD4 cell count <200 CD4/ml was observed in 15%. Clearance of HCV-RNA in end of treatment was seen in 46 % and sustained virological response in 34 %. The main predictors of sustained virological response were HCV genotype 2 or 3 (P =0.04) and plasma HIV RNA less than 50 copies/ml (P =0.001). The predictive value of good virological response of a CD4 cell count >350/ml before treatment was very near the statistical significancy (p =0.07).

CONCLUSIONS

The efficacy of pegylated interferon plus ribavirin in HIV-HCV co-infected patients is disappointing mainly due to a poor tolerance. In addition to HCV genotype, plasma HIV RNA level and CD4 cell count were essential to predict INFpeg-Riba response and should be taken into account in the process leading to the initiation of such therapy in HIV-HCV co-infected patients.

Tolérance et interactions médicamenteuses des traitements anti-VIH et anti-VHC

Treating Hepatitis C among HIV patients under antiretroviral drug therapy requires a high degree of vigilance and continuous monitoring because of frequent problems with intolerance and/or drug interactions. Recent studies, including three therapeutic trials, on Ribavic, APRICOT, and ACTG A5671, have given some insights on following these patients up. The adverse effects are relatively similar in HCV-HIV-co-infected patients and patients infected by HCV only. Their frequency is, on the other hand, higher among HCV-HIV-Co-infected patients. The adverse-effects are consistent, in a non-exhaustive way, with pseudo influenza-like symptoms, fever, myalgia, cephalgia, with psychiatric disorders (irritability, depression, etc.); endocrine disorders (thyroid dysfunction, diabetes...); and with hematological anomalies especially anemia and leucopenia. But the percentage of lymphocyte T CD4 is not modified, therefore there is no risk of opportunistic infection. Pharmacokinetic interactions between antiretroviral drugs and treatment for HCV infection including ribavirin plus interferon alpha (IFN-alpha) or pegylated IFN are described. They are almost exclusively due to the combination of ribavirin and of nucleoside analogue reverse transcriptase inhibitors. One of the principal consequences is the emergence of mitochondrial toxicity defined by the occurrence of hyperlactatemia, or acute pancreatitis). Thus, some combinations should be avoided such as ddI+ribavirin and ddI+d4T+ribavirin. The d4T+ribavirin combination must also be used with caution.

Treatment of chronic hepatitis C in HIV/HCV-coinfection with interferon alpha-2b+ full-course vs. 16-week delayed ribavirin

Human immunodeficiency virus (HIV)-infected patients increasingly experience the consequences of chronic hepatitis C virus (HCV) coinfection. This trial randomized 107 patients coinfected with HIV and HCV to receive 48 weeks of interferon alfa-2b (IFN) 3 million units three times weekly plus either a full course of ribavirin (RBV) at 800 mg/day (group A; n = 53) or 16 weeks of placebo, followed by RBV (group B; n = 54). The primary endpoint of sustained viral response (SVR) rate (undetectable HCV RNA at posttreatment week 24) was not different between groups A (11.3%) and B (5.6%; P =.32). Within group A, the SVR rate was lower in genotype 1 (2.5%) than in genotypes 2 through 4 (41.7%; P =.002). Fifty-five patients discontinued therapy prematurely, mostly because of adverse events or patient decisions. At treatment week 12, the percentage of CD4+ cells rose in group A (+4.1%; P <.001), but not in group B (-0.3%). A significant proportion (22%) of patients who were HIV viremic at baseline had undetectable HIV RNA at week 12. By week 16, the hemoglobin level decreased more in group A (-2,52 g/dL) than in group B (-1.02 g/dL; P <.001). In group A, the hemoglobin decline was steeper in patients receiving zidovudine (azidothymidine [AZT], -3.64 g/dL vs. no AZT, -2.08 g/dL), and patients receiving zidovudine had more anemia-related RBV dose reductions (AZT, 60% vs. no AZT, 16%). In conclusion, HCV therapy with IFN plus RBV is relatively safe in patients coinfected with HIV and HCV, but frequent treatment discontinuations and anemia-related RBV dose reductions contribute to a poor SVR rate. Control of HIV infection improves rather than worsens during therapy.

The cellular pharmacology of nucleoside- and nucleotide-analogue reverse-transcriptase inhibitors and its relationship to clinical toxicities

Nucleoside- and nucleotide-analogue reverse-transcriptase inhibitors (NRTIs) require intracellular phosphorylation for anti-human immunodeficiency virus (HIV) activity and toxicity. Long-term toxicities associated with NRTIs may be related to overactivation of this process. In vitro experiments have shown increased rates of NRTI and endogenous nucleoside phosphorylation to be associated with cellular activation. Patients with advanced HIV disease often have overexpression of cytokines, which corresponds to an elevated cellular activation state. These patients also have higher rates of NRTI phosphorylation and NRTI toxicity, suggesting an interaction between a proinflammatory biological state, NRTI phosphorylation, and toxicity. Studies suggest that women may have higher rates of NRTI phosphorylation than do men, as well as increased risk for NRTI-induced toxicity. Future research is needed to understand the NRTI activation process and improve the long-term toxicity profile of NRTIs. Such research should include comparisons of NRTI phosphorylation according to sex and cellular activation state (i.e., elevated vs. low).