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Biomedical subjects

Gilles Peytavin

Publications and source records attributed to Gilles Peytavin.

At least 37 records · Page 2Linked to original sources
PubMed2005

Intermittent viremia during first-line, protease inhibitors-containing therapy: significance and relationship with drug resistance.

BACKGROUND: In HIV-infected patients on first-line antiretroviral therapy, the significance of intermittent viremia and their relationship with drug resistance remain unclear. OBJECTIVE: To study the virological characteristics of intermittent viremia (IV) and the association between IV and later virological failure (VF) in patients on a first-line, PI-containing therapy. STUDY DESIGN: Antiretroviral-naive patients were enrolled in the APROVIR substudy of the prospective, multicenter APROCO cohort at the time they initiated a PI-containing therapy and were followed-up at month 1 and every 2 months. IV was defined as plasma HIV-1 RNA > 500 copies/ml on a single specimen. VF were defined as: (1) viral rebound on two consecutive plasma specimens with HIV-1 RNA > 500 copies/ml after an initial response below 500 copies/ml, or (2) persistence of plasma HIV-1 RNA> or =500 copies/ml during the first year of follow-up. Genotypic resistance analysis was performed at baseline and at the time of IV. PI plasma concentrations were determined at the time of IV. RESULTS: IV was found in 20/219 patients in a 2 years follow-up. The occurrence of IV in the first year of therapy was associated with a higher risk of virological failure during the second year (p = 0.03). Genotypic resistance at the time of IV was found in only 4/16 patients and was not predictive of a subsequent virological failure. PI plasma levels suggested lack of adherence in 50% of patients with IV. CONCLUSION: The occurrence of IV > 500 copies/ml among patients on first-line, PI-containing ART is suggestive of a lack of adherence rather than the selection of resistant variants and should lead to an intensification of adherence monitoring in order to reduce the risk of subsequent VF.

Anti-HIV Agents↗
PubMed2005

Indinavir plasma concentration and adherence score are codeterminant of early virologic response in HIV-infected patients of the APROCO cohort.

To study the respective roles of indinavir concentrations and treatment adherence as predictors of early virologic response, we analyzed the patients of the APROCO cohort treated by indinavir 800 mg TID during the first 4 months. Minimum (Cmin), maximum (Cmax), and the ratio of the measured to expected concentrations (CR) were estimated for each patient at M4, from a population pharmacokinetic analysis of all data. The relationship among virologic success at M4 [plasma HIV RNA (VL) <500 copies/mL], baseline characteristics, estimated indinavir concentrations, and adherence score measured by a self-administered questionnaire, was analyzed by multivariate logistic regression. In the 216 studied patients, baseline median HIV RNA was 4.4 log10 copies/mL, and CD4 cell count was 309/mm. Virologic success was achieved in 195 (90%) patients; it was independently related to baseline viral load (OR = 0.524, CI 0.29-0.93; P = 0.03), antiretroviral treatment naive status (OR = 3.89, CI 1.29-11.76; P = 0.01), and indinavir Cmin (OR = 1.06, CI 1.02-1.10; P = 0.004) when adherence score was not included in the model, whereas full adherence was the only independent related factor when included in the model (OR = 8.8, 95% CI 2.85-27.3; P < 10). In the 168 fully adherent patients, virologic success was more frequent in patients with shorter duration of antiretrovirals at baseline (P = 0.03), lower baseline HIV RNA (P = 0.03), and higher indinavir CR (P < 10); the most discriminating Cmin cut-off was 194 ng/mL. Data on the relationship between indinavir plasma concentration and virologic success are therefore misleading without a concomitant assessment of adherence. These data suggest that any strategy of therapeutic drug monitoring must imply first a combined evaluation of plasma concentrations and adherence level and second an intervention target based on the results of both assessments.

Adult↗
PubMed2005

Virological and pharmacological parameters predicting the response to lopinavir-ritonavir in heavily protease inhibitor-experienced patients.

The genotypic inhibitory quotient (GIQ) has been proposed as a way to integrate drug exposure and genotypic resistance to protease inhibitors and can be useful to enhance the predictivity of virologic response for boosted protease inhibitors. The aim of this study was to evaluate the predictivity of the GIQ in 116 protease inhibitor-experienced patients treated with lopinavir-ritonavir. The overall decrease in human immunodeficiency virus type 1 (HIV-1) RNA from baseline to month 6 was a median of -1.50 log(10) copies/ml and 40% of patients had plasma HIV-1 RNA below 400 copies/ml at month 6. The overall median lopinavir study-state C(min) concentration was 5,856 ng/ml. Using univariate linear regression analyses, both lopinavir GIQ and the number of baseline lopinavir mutations were highly associated with virologic response through 6 months. In the multivariate analysis, only lopinavir GIQ, baseline HIV RNA, and the number of prior protease inhibitors were significantly associated with response. When the analysis was limited to patients with more highly mutant viruses (three or more lopinavir mutations), only lopinavir GIQ remained significantly associated with virologic response. This study suggests that GIQ could be a better predictor of the virologic response than virological (genotype) or pharmacological (minimal plasma concentration) approaches used separately, especially among patients with at least three protease inhibitor resistance mutations. Therapeutic drug monitoring for patients treated by lopinavir-ritonavir would likely be most useful in patients with substantially resistant viruses.

Adult↗
PubMed2005

Comparative selection of the K65R and M184V/I mutations in human immunodeficiency virus type 1-infected patients enrolled in a trial of first-line triple-nucleoside analog therapy (Tonus IMEA 021).

Tonus was a pilot study in which previously untreated human immunodeficiency virus type 1 (HIV-1)-infected patients received the combination of abacavir, lamivudine, and tenofovir once a day. There was a high rate of early virological failure, and the M184V and K65R mutations were frequently detected at week 12 (W12). The objective of this study was to examine the selection dynamics of the K65R and M184V/I mutations. Bulk sequencing of the reverse transcriptase (RT) gene was performed on plasma HIV-1 RNA at baseline, W4, and W12 for 21 patients with detectable viral loads. The RT genes from baseline, W4, and W12 plasma samples from five patients who developed both M184V and K65R but with different mutational patterns were also cloned and screened for the K65R mutation by selective real-time PCR. At baseline, bulk sequencing and clonal analysis showed only wild-type RT sequences. At W4, M184V/I was detected in 12/19 patients and K65K/R in 2 patients by bulk sequencing. At W12, M184V/I was found in 18/20 patient, together with the K65R in 13 patients. At W4, clonal analysis revealed the K65R mutation in 0.6 to 48% of clones in the five patients studied. At W12, the K65R mutation was found in 30 to 100% of clones. K65R and M184V/I seemed to arise in separate clones, followed by an enrichment of viruses containing both mutations. The clinical relevance of this independent evolution is unclear. M184V/I was selected more frequently than K65R at W4. However, K65R was also detected early using a clone-sensitive genotyping method. All three nucleoside analogs are known to select the K65R and/or M184V/I mutation. This convergent genetic pathway to resistance, associated with lower antiretroviral potency, may explain the high selection rate of these mutations in this trial.

Adenine↗
PubMed2005

High variability of indinavir and nelfinavir pharmacokinetics in HIV-infected patients with a sustained virological response on highly active antiretroviral therapy.

OBJECTIVES: To describe plasma concentrations of indinavir alone or combined with ritonavir, and of nelfinavir and its active metabolite M8, and to measure their variabilities in HIV-infected patients treated with a stable antiretroviral regimen and experiencing a sustained virological response for at least 12 months. PATIENTS AND METHODS: In this prospective trial, blood samples were drawn during a 6-hour time interval between two doses at enrolment to assess protease inhibitor (PI) pharmacokinetic parameters, and 4 months later to assess plasma trough and peak concentrations. Safety and adherence assessments and laboratory data were collected during an 8-month period. PI pharmacokinetic characteristics were analysed using a non-compartmental approach. Inter- and intrapatient variabilities were estimated using a linear mixed-effect model. The impact of different covariates on plasma trough concentrations was investigated. Eighty-eight patients were analysed: 42 treated with indinavir and 46 with nelfinavir. RESULTS: The interquartile range (IQR) of the plasma trough concentration corrected for the sampling time (Ccalc) was 116-374 microg/L for indinavir alone and 163-508 microg/L for indinavir/ritonavir. Ritonavir significantly increased indinavir elimination half-life and plasma exposure. For nelfinavir, the IQR of Ccalc was 896-2059 microg/L for three-times-daily administration and 998-2124 microg/L for twice-daily administration. Variabilities were high for both PIs. Intrapatient variability for indinavir alone (and indinavir + ritonavir) was 76% (107%) and interpatient variability was 58% (10%) in adherent patients. Intrapatient variability for nelfinavir three times daily (and twice daily) was 41% (74%) and interpatient variability was 62% (50%). Intrapatient variability was lowered in patients with a high adherence level. CONCLUSION: Although performed in a homogeneous population, this study documented a high interpatient but also intrapatient variability of indinavir and nelfinavir pharmacokinetics, which should be taken into account when interpreting therapeutic drug monitoring. Once patients have reached a sustained virological response, plasma PI monitoring may have a limited impact.

Adult↗
PubMed2005

Current status and future prospects of therapeutic drug monitoring and applied clinical pharmacology in antiretroviral therapy.

The consensus of current international guidelines for the treatment of HIV infection is that data on therapeutic drug monitoring (TDM) of non-nucleoside reverse transcriptase inhibitors and protease inhibitors provide a framework for the implementation of TDM in certain defined scenarios in clinical practice. However, the utility of TDM is considered to be on an individual basis until more data are obtained from large clinical trials showing the benefit of TDM. In April 2004, a panel of experts met in Rome, Italy. This followed an inaugural meeting in Perugia, Italy, in October 2000, which resulted in the article published in AIDS 2002, 16(Suppl 1):S5-S37. The objectives of this second meeting were to review the questions surrounding TDM of antiretroviral drugs and discuss the clinical utility, current concerns and future prospects of drug concentration monitoring in the care of HIV-1-infected individuals. This report, which has been updated to include material published or presented at international conferences up to the end of September 2004, reviews pharmacokinetic and pharmacodynamic data and reports the issues discussed by the panel, offering advice to clinical care providers who may be currently, or are considering incorporating TDM into the routine care of their patients. In addition, the panel formulated a series of position statements that are relevant to the interpretation of current data and can aid the design of future clinical trials.

Anti-HIV Agents↗
PubMed2005

Therapeutic drug monitoring and drug-drug interactions involving antiretroviral drugs.

The consensus of current international guidelines for the treatment of HIV infection is that data on therapeutic drug monitoring (TDM) of non-nucleoside reverse transcriptase inhibitors (NNRTIs) and protease inhibitors (Pls) provide a framework for the implementation of TDM in certain defined scenarios in clinical practice. However, the utility of TDM is considered to be on an individual basis until more data are obtained from large clinical trials showing the benefit of TDM. In April 2004, a panel of experts met for the second time in Rome, Italy. This was following the inaugural meeting in Perugia, Italy, in October 2000, which resulted in the manuscript published in AIDS 2002, 16(Suppl 1):S5-S37. The objectives of this second meeting were to review and update the numerous questions surrounding TDM of antiretroviral drugs and discuss the clinical utility, current concerns and future prospects of drug concentration monitoring in the care of HIV-1-infected individuals. A major focus of the meeting was to discuss and critically analyse recent and precedent clinical drug-drug interaction data to provide a clear framework of the pharmacological basis of how one drug may impact the disposition of another. This report, which has been updated to include material published or presented at international conferences up to the end of December 2004, reviews recent pivotal pharmacokinetic interaction data and provides advice to clinical care providers on how some drug-drug interactions may be prevented, avoided or managed, and, when data are available, on what dose adjustments and interventions should be performed.

Anti-HIV Agents↗
PubMed2005

Letter. In vitro phenotypic susceptibility to nucleoside reverse transcriptase inhibitors of HIV-2 isolates with the Q151M mutation in the reverse transcriptase gene.

In HIV-2 infection, many studies have reported a high frequency of selection of the Q151M mutation, but its impact on phenotypic susceptibility of HIV-2 isolates remains unclear. Four HIV-2 infected patients from the French ANRS HIV-2 cohort, with evidence of Q151M mutation in both plasma and available peripheral blood mononuclear cells (PBMCs) co-cultivated supernatants, were selected. In vitro phenotypic susceptibilities to different nucleoside reverse transcriptase inhibitors (NRTIs) were determined using a PBMC assay. In HIV-2 isolates, the Q151M mutation alone impacts only the phenotypic susceptibility to stavudine and abacavir. A decrease in susceptibility to all NRTIs was observed when Q151M was selected with V111I, a mutation of unknown impact on HIV-1 resistance. Clinical relevance of these phenotypic susceptibility results needs to be evaluated in HIV-2 treated patients.

Drug Resistance, Multiple, Viral↗
PubMed2004

Penetration of enfuvirtide, tenofovir, efavirenz, and protease inhibitors in the genital tract of HIV-1-infected men.

One likely mechanism of virological failure is poor antiretroviral drug diffusion in sites of viral replication such as the genital tract. We measured antiretroviral drug concentrations in blood and semen in 13 HIV-infected men failing treatment. Enfuvirtide did not cross the blood-testis barrier, whereas tenofovir accumulated in semen. Unlike indinavir, semen concentrations of lopinavir, amprenavir, saquinavir and efavirenz were ineffective. These are worrying findings, because suboptimal semen drug concentrations may enhance the risk of sexually transmitted drug-resistant HIV variants.

Adenine↗
PubMed2004

Benefit of treatment interruption in HIV-infected patients with multiple therapeutic failures: a randomized controlled trial (ANRS 097).

BACKGROUND: Both highly potent antiretroviral drug rescue therapy and treatment interruption have been suggested to be effective in patients with multiple treatment failure. OBJECTIVE: To assess both the benefits and risks of an 8-week treatment interruption associated with a six to nine-drug rescue regimen in patients with multiple treatment failures. DESIGN: A randomized comparative controlled trial in 19 university hospitals in France. PATIENTS: Sixty-eight HIV-infected patients with multiple previous treatment failures and CD4 cell counts less than 200 x 10(6) cells/l and plasma HIV-1-RNA levels of 50,000 copies/ml or greater. MEASUREMENTS: The primary efficacy outcome was the proportion of patients with at least a 1 log10 decrease (copies/ml) in the plasma HIV-1-RNA level after 12 weeks of therapy. RESULTS: Treatment interruption followed by multidrug salvage therapy led to a greater proportion of patients achieving virological success (i.e. 1 log10 decrease) at 12 weeks compared with patients receiving multidrug therapy alone (62 versus 26%, intent-to-treat analysis; P = 0.007). The median decrease in the HIV-1-RNA level was -1.91 and -0.37 log10 copies/ml (P = 0.008), respectively. Treatment interruption led to an increase in the number of sensitive drugs of the multidrug regimen (71 versus 35% of regimen with at least two sensitive drugs; P = 0.004). Factors associated with virological success were treatment interruption, the reversion of at least one mutation to wild type, adequate plasma drug concentration, and the use of lopinavir. CONCLUSION: Treatment interruption was beneficial for treatment-experienced HIV-infected patients with advanced HIV disease and multidrug-resistant virus.

Adolescent↗
PubMed2004

Resistance profiles observed in virological failures after 24 weeks of amprenavir/ritonavir containing regimen in protease inhibitor experienced patients.

Amprenavir (APV) is an HIV protease inhibitor (PI) used for the treatment of either naive or PI-experienced HIV-infected patients. Several genotypic resistance pathways in protease gene have been described to be associated to unboosted APV failure (I50V, V32I + I47V, I54L/M, or less commonly I84V, which may be accompanied by one ore more accessory mutations such as L10F, L33F, M46I/L). The aims of this study were to investigate the efficacy up to week 24 of an APV plus ritonavir containing regimen in PI experienced patients and to determine the genotypic resistance profiles emerging in patients failing to this therapy. Forty-nine, PI experienced but APV naïve patients were treated with APV (600 mg bid) plus ritonavir (100 mg bid). By intent-to-treat analysis, the median decrease in viral load (VL) was -1.32 log10 (min +0.6; max -2.8) and -1.46 log10 (min +0.5; max -2.8) 12 and 24 weeks after initiating APV plus ritonavir regimen, respectively. Twelve patients harboured a VL >200 copies/ml at week 24. Among these patients, the selection of mutations previously described with the use of APV as first PI (V32I, L33F, M46I/L, I50V, 54M/L, and I84V) was observed. However, in some cases, mutations classically described after the use of other PIs (V82F and L90M) were selected but always with APV-specific mutations. There was no relation between the resistance pathways selected with either APV or ritonavir plasma minimal concentration, but higher APV plasma minimal concentration were associated with a lower rate of resistance mutations selection.

Adult↗
PubMed2004

Tubulopathy consecutive to tenofovir-containing antiretroviral therapy in two patients infected with human immunodeficiency virus-1.

Tenofovir disopril fumarate, a new nucleotide analogue against human immunodeficiency virus-1 (HIV-1), can induce hypophosphataemia, the mechanism of which is unclear. Moreover, a renal tubulopathy can occur in long-term treated patients, as observed in 2 HIV-1-infected patients after 12 months of tenofovir therapy, with polyuria-polydipsia, proteinuria, glycosuria and amino-aciduria, which resolved after discontinuation of tenofovir. The risk of renal tubulopathy symptoms in patients on long-term tenofovir therapy should be noted.

Adenine↗
PubMed2004

Evolution of human immunodeficiency virus type 1 (HIV-1) resistance mutations in nonnucleoside reverse transcriptase inhibitors (NNRTIs) in HIV-1-infected patients switched to antiretroviral therapy without NNRTIs.

We studied the evolution of nonnucleoside reverse transcriptase inhibitor (NNRTI) resistance mutations among 29 human immunodeficiency virus type 1 (HIV-1)-infected patients who experienced virologic failure when receiving an NNRTI-containing regimen (nevirapine, delavirdine, or efavirenz) and subsequently switched to antiretroviral therapy without NNRTIs. Genotypic resistance was determined from plasma samples collected at the time of NNRTI withdrawal (baseline) and during follow-up. At baseline, 83% of patients had more than two thymidine analog resistance mutations (TAMs), and all had NNRTI resistance mutations. Mutations at codons 103, 181, and 190 were found in 62, 62, and 34% of the patients, respectively. Follow-up samples were available after a median time of 6 months in all patients and at 12 months in 22 patients. The mean number of resistance mutations to NNRTIs was significantly lower at months 6 (1.34 +/- 1.04) and 12 (1.18 +/- 1.05) than at month 0 (2.03 +/- 1.02) (P < 0.009). The percentages of patients with at least one NNRTI resistance mutation were 100, 76, and 73% at baseline, month 6, and month 12, respectively (P < 0.0044). Overall, 70% of the patients had a mutation at codon 103 or 181 at month 12. The mean number of TAMs did not vary significantly during follow-up. Our data show that, in the context of maintained antiretroviral therapy, NNRTI resistance mutations persist in two-thirds of the patients in spite of NNRTI withdrawal. These results argue for the low impact of NNRTI resistance mutations on viral fitness and suggest that resistance mutations to different classes of drugs are associated on the same genome, at least in some of the resistant strains.

Antiretroviral Therapy, Highly Active↗
PubMed2004

Clinically relevant interpretation of genotype and relationship to plasma drug concentrations for resistance to saquinavir-ritonavir in human immunodeficiency virus type 1 protease inhibitor-experienced patients.

It has been shown that virological protease inhibitor (PI) resistance mutations present at the initiation of saquinavir (SQV) plus ritonavir (RTV) therapy in PI-experienced patients are the strongest predictors of virological response. But most of the current resistance algorithms are adapted for unboosted SQV regimens. We applied a stepwise methodology for the development and validation of a clinically relevant genotypic resistance score for an SQV (800 mg twice per day [b.i.d.]) plus RTV (100 mg b.i.d.)-containing regimen. PI-experienced patients treated by this regimen achieved a human immunodeficiency virus plasma viral load (VL) of <200 copies/ml at months 3 to 5 for 41.7% of subjects. Adjusted in a multivariate analysis, taking into account all the confounding factors, such as the nucleoside used, five mutations were combined in a resistance score associated with a reduced virological response to an SQV-plus-RTV regimen: L24I, I62V, V82A/F/T/S, I84V, and L90IM. Patients with isolates harboring 0 to 1 mutation among the score achieved -2.20 log10 and -1.23 log10 copies/ml of VL reduction, respectively, while it was -0.27 log10 copies/ml for those with at least two mutations, classifying the isolates as "no evidence of resistance" (0 or 1 mutation) or "resistance " (> or =2 mutations). The minimum concentration in plasma (Cmin) of SQV alone was not associated with the virological response. However, the combination of the SQV Cmin and the genotypic score, expressed as the genotypic inhibitory quotient, was predictive of the virological response, suggesting that the interpretation of SQV concentrations in plasma should be done only in the context of the resistance index provided by viral genotype for PI-experienced patients.

Codon↗
PubMed2004

Once-daily dosing of saquinavir soft-gel capsules and ritonavir combination in HIV-1-infected patients (IMEA015 study).

This was a prospective pilot study evaluating a saquinavir (SQV) soft-gel capsules (SGC)/ritonavir (RTV)-containing once-daily regimen over a follow-up of 3 months. The primary end-point was to determine the number of patients both remaining on treatment at month 3 and with trough SQV plasma concentration 24 h after the last intake (C24h) exceeding the inhibition of 95% of viral replication in vitro (IC95). The secondary end-points were to investigate the immuno-virological efficacy and safety of SQV-SGC/RTV once daily, and to explore SQV concentrations in peripheral blood mononuclear cells (PBMCs). Twenty-three antiretroviral-naive and 17 protease inhibitors (PIs) experienced HIV-1-infected patients with plasma HIV-1 RNA level below 200 copies/ml were enrolled. They were assigned to SQV-SGC/RTV (1600/100 mg once daily) combined with nucleoside and/or non-nucleoside reverse transcriptase inhibitors. In a subgroup of 13 patients, both plasma and intracellular SQV concentrations were determined. By intent to treat analysis the percentage of success at month 3 was 87.5% (confidence interval: 73.2-95.8%) with 78.3% in naive and 100% in PI-experienced patients. SQV C24h and intracellular concentrations [median (range, n)] were 241 ng/ml (40-1209, 35) and 323 ng/ml (168-475, 12), respectively. Intracellular concentrations showed an accumulation of SQV in PBMCs persisting during 24 h. Neither immunological nor virological failure was observed. Clinical and biological tolerance was acceptable in all patients but three with adverse effects leading to discontinuation. These data confirmed the short-term efficacy of SQV-SGC/RTV once-daily regimen based on SQV therapeutic drug monitoring.

Adult↗