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Pierre-Marie Girard

Publications and source records attributed to Pierre-Marie Girard.

At least 37 records · Page 2Linked to original sources

Early plasmacytoid dendritic cell changes predict plasma HIV load rebound during primary infection.

During human immunodeficiency virus (HIV) infection, interruption of highly active antiretroviral therapy (HAART) is usually followed by virus load rebound. Previous data have suggested a role for plasmacytoid dendritic cells (pDCs) in anti-HIV innate immunity. Here, the number of pDCs was measured by flow cytometry before, during, and after receipt of HAART in 7 patients with documented primary HIV-1 infection. A negative correlation was evidenced between pDC counts after 1 month of HAART and mean plasma virus load after interruption of HAART (r2=0.85; Spearman's partial rho =-0.92; P=.03). pDC counts during treatment might help predict immune replication control after interruption of HAART.

Adult↗

Analysis of DNA ligase IV mutations found in LIG4 syndrome patients: the impact of two linked polymorphisms.

LIG4 syndrome patients have hypomorphic mutations in DNA ligase IV. Although four of the five identified patients display immunodeficiency and developmental delay, one patient was developmentally normal. The developmentally normal patient had the same homozygous mutation (R278H) in DNA ligase IV as one of the more severely affected patients, who additionally had two linked polymorphisms. Here, we examine the impact of the mutations and polymorphisms identified in the LIG4 syndrome patients. Examination of recombinant mutant proteins shows that the severity of the clinical features correlates with the level of residual ligase activity. The polymorphisms decrease the activity of DNA ligase IV by approximately 2-fold. When combined with the otherwise mild R278H mutation, the activity is reduced to a level similar to other LIG4 patients who display immunodeficiency and developmental delay. This demonstrates how coupling of a mutation and polymorphism can have a marked impact on protein function and provides an example where a polymorphism may have influenced clinical outcome. Analysis of additional mutational changes in LIG4 syndrome (R580X, R814X and G469E) have led to the identification of a nuclear localization signal in DNA ligase IV and sites impacting upon DNA ligase IV adenylation.

Animals↗

Virological and immunological impact of non-nucleoside reverse transcriptase inhibitor withdrawal in HIV-infected patients with multiple treatment failures.

No significant changes in viral load and CD4 cell count were observed 2-4 weeks after the withdrawal of non-nucleoside reverse transcriptase inhibitors (NNRTI) from the current therapy of patients exhibiting resistance mutations to this class of drugs. The data suggest that in the presence of specific resistance mutations NNRTIexert no residual antiretroviral activity and could be withdrawn without viral rebound.

CD4 Lymphocyte Count↗

Interactions between amprenavir and the lopinavir-ritonavir combination in heavily pretreated patients infected with human immunodeficiency virus.

OBJECTIVE: This pharmacokinetic study was designed to characterize interactions between amprenavir and the lopinavir-ritonavir combination in patients infected with human immunodeficiency virus in whom previous antiretroviral therapy had failed. METHODS: Twenty-seven patients included in a randomized clinical trial (ANRS [National Agency for AIDS Research] Protocol 104) participated in this study. They were randomized to receive ritonavir at a dose of either 100 mg twice daily or 200 mg twice daily. For the first 2 weeks of therapy, they were randomly assigned to receive lopinavir (400 mg twice daily) and ritonavir (100 mg twice daily), amprenavir (600 mg twice daily) plus ritonavir (100 mg twice daily), lopinavir (400 mg twice daily) and ritonavir (100 mg twice daily) plus additional ritonavir (100 mg twice daily), or amprenavir (600 mg twice daily) plus ritonavir (200 mg twice daily). From week 3 onward, all patients received amprenavir plus lopinavir-ritonavir with or without an additional ritonavir dose (100 mg twice daily). The pharmacokinetics of the 3 drugs was studied in weeks 2 and 6 of therapy. RESULTS: Median amprenavir concentrations decreased by 54% (P =.004) when lopinavir was added to the amprenavir-ritonavir regimen. Lopinavir weakly displaced amprenavir from plasma proteins: The average unbound fraction of amprenavir was 0.089 in week 2 and 0.114 in week 6 (P =.03), but this did not fully account for the observed interaction. Increasing the ritonavir dose did not affect the amprenavir concentration. The relationship between lopinavir and ritonavir concentrations fitted a maximum effect (E(max)) model;the average concentration of ritonavir that yielded a lopinavir concentration of 8119 ng/mL (50% of E(max)) was 602 ng/mL (coefficient of variation, 22%). There was a significant relationship between the lopinavir inhibitory quotient and the virologic response in week 2 (P =.005). CONCLUSION: Lopinavir markedly decreases the amprenavir concentration during amprenavir and lopinavir-ritonavir combination therapy. The inhibitory quotients were more predictive of the short-term virologic response than was the level of drug exposure.

Administration, Oral↗

Interactions between atazanavir-ritonavir and tenofovir in heavily pretreated human immunodeficiency virus-infected patients.

The aim of the present study was to assess the pharmacokinetic behavior of atazanavir-ritonavir when it is coadministered with tenofovir disoproxil fumarate (DF) in human immunodeficiency virus (HIV)-infected patients. Eleven patients enrolled in Agence Nationale de Recherche sur le SIDA (National Agency for AIDS Research, Paris, France) trial 107 were included in this pharmacokinetic study. They received atazanavir at 300 mg and ritonavir at 100 mg once a day (QD) from day 1 to the end of study. For the first 2 weeks, their nucleoside analog reverse transcriptase inhibitor (NRTI) treatments remained unchanged. Tenofovir DF was administered QD from day 15 to the end of the study. Ongoing NRTIs were selected according to the reverse transcriptase genotype of the HIV isolates from each patient. The values of the pharmacokinetic parameters for atazanavir and ritonavir were measured before (day 14 [week 2]) and after (day 42 [week 6]) initiation of tenofovir DF and are reported for the 10 patients who completed the study. There was a significant decrease in the area under the concentration-time curve from 0 to 24 h (AUC(0-24)) for atazanavir with the addition of tenofovir DF (AUC(0-24) ratio, 0.75; 90% confidence interval, 0.58 to 0.97; P = 0.05). There was a trend for a decrease in the minimum concentrations of atazanavir and ritonavir in plasma when they were combined with tenofovir, but none of the differences reached statistical significance. The median decreases in the HIV RNA loads at week 2 and week 6 were 0.1 and 0.2 log copies/ml, respectively. In summary, our data are consistent with the existence of a significant interaction between atazanavir and tenofovir DF.

Adenine↗

Impact of insertions in the HIV-1 p6 PTAPP region on the virological response to amprenavir.

We evaluated the impact of genetic changes within p6Gag gene on the virological response (VR, mean decrease in plasma viral load at week 12) to unboosted amprenavir (APV). Gag-protease fragments, including gag p2, p7, p1, p6 regions and whole protease (PR) were sequenced from baseline plasma specimens of 84 highly pre-treated but APV-naive patients included in the NARVAL (ANRS 088) trial. The correlation between baseline p6Gag polymorphism, PR mutations, baseline characteristics and VR to APV was analysed in univariate analysis. Insertions (P459Ins) within p6 protein, leading to partial or complete duplication of the PTAPP motif, were significantly associated with a decreased VR (P459Ins versus wild-type; -0.3 +/- 0.8 vs -1.1 +/- 1.2 log copies/ml, P=0.007) and were more frequent when the V82A/F/T/S PR mutation was present (P=0.020). In multivariate analysis, after adjustment on the predictive factors of the VR in the NARVAL trial and on the PR mutations linked with response, there was a strong trend to an association (P=0.058) between the presence of P459Ins and an altered VR. In conclusion, these results suggest that insertions in the p6 region of HIV-1 gag gene may affect the VR, in highly pre-treated patients receiving an unboosted APV-containing regimen.

Adult↗

Persistence of multidrug-resistant HIV-1 without antiretroviral treatment 2 years after sexual transmission.

OBJECTIVES: To understand the virological mechanisms of 2-year persistence of multidrug-resistant virus without selective antiretroviral pressure in HIV-1-infected patients. PATIENTS AND METHODS: Two patients were contaminated recently by their HIV-1-infected partners, who had received, before the transmission, all available antiretroviral drugs and who exhibited a severe therapeutic failure. The resistance mutations analysis was performed by clonal sequencing of 1.2 kb of pol gene in plasma of index and sources patients. Sequencing of HIV-1 DNA was performed in PBMCs of index patients. RESULTS: Genotypic testing performed in index patients at time of seroconversion showed resistance mutations to three classes of drugs. All mutations were linked on the same viral genome and all quasispecies carried all mutations. No wild-type virus was detected. The same results were found in source patients and showed that all mutations were transmitted. In the index patients, all mutations persisted over 2 years without antiretroviral treatment. Moreover, the resistance mutations were all archived in the cellular reservoir. Viral load and CD4 count of index patients remained unchanged during 2 years of follow-up. DISCUSSION: Only multidrug-resistant viruses were detected in the source patients and could be transmitted in index patients. In the latter, an expansion of predominant multidrug-resistant quasispecies and the 'archival' of all mutations were observed. These results explain the persistence of mutations and suggest that it is highly difficult to return to a wild-type viral population, sensitive to an antiretroviral treatment. The treatment of index patients is limited and the major risk is the transmission of these multidrug-resistant viruses. This work was presented in part in the XII International HIV Drug Resistance Workshop, Los Cabos, Mexico, June 2003; and in the 2nd IAS Conference on HIV Pathogenesis & Treatment, Paris, France, July 2003.

Adult↗

Altered fat differentiation and adipocytokine expression are inter-related and linked to morphological changes and insulin resistance in HIV-1-infected lipodystrophic patients.

OBJECTIVE: To achieve a better understand of the pathophysiology of HIV-related lipoatrophy, we compared the mRNA expression of adipocytokines in fat samples from patients and healthy HIV-seronegative controls together with fat morphology and we studied the relationship between changes in fat morphology, adipocytokine expression, markers of adipose tissue differentiation and whole body insulin sensitivity. DESIGN: Cross-sectional analytical study. SUBJECTS AND METHODS: The mRNA expression of adipocytokines and transcriptional factors in fat samples from 26 patients with peripheral lipoatrophy (all under anti-retroviral therapy associating protease inhibitor and nucleoside-analogue reverse transcriptase inhibitors) and from 16 non-HIV-infected controls was measured by real time quantitative RT-PCR. Fat morphology was assessed histologically on a subgroup of 10 patients and six controls: collagen fibres by Sirius Red staining, apoptosis by the TUNEL technique, vessels by smooth muscle alpha-actin staining and macrophages by CD68 staining. Insulin resistance was assessed by using the homeostasis model assessment. RESULTS: The patients' fat showed higher values of apoptosis (P=0.005), fibrosis (P<0.05), vessel density (P=0.001) and macrophage infiltration (P<0.05) than the controls' fat, together with lower adiponectin and leptin mRNA levels and higher interleukin (IL)-6 and tumour necrosis factor (TNF)alpha mRNA levels. TNFa and IL-6 expression correlated positively with the level of apoptosis (P=0.05 and P<0.05, respectively) and negatively with CCAAT-enhancer binding protein (C/EBP)alpha (P<0.001 and P<0.05, respectively). Apoptosis correlated negatively with the expression level of sterol-regulatory-element-binding-protein-1c (SREBP1c) (P=0.01) and C/EBPalpha (P=0.01) whilst the vessel density correlated negatively with SREBP1c (P<0.005), C/EBPalpha (P=0.001) and beta (P=0.001). Adiponectin and leptin expression correlated positively with each other, and also with adipogenic marker expression and overall insulin sensitivity. These relationships were also present when the patient group was studied separately. Finally, fat morphological abnormalities correlated positively with whole body insulin resistance. CONCLUSIONS: Adipose tissue from patients with HIV-1-related lipoatrophy shows increased apoptosis, together with decreased adipocyte differentiation. Increased TNFalpha and IL-6 expression could be a major phenomenon linking these alterations. Decreased adiponectin and leptin expression, which may result from decreased adipocyte differentiation, could be involved in the observed whole body insulin resistance.

Adipocytes↗

Salvage therapy with amprenavir, lopinavir and ritonavir 200 mg/d or 400 mg/d in HIV-infected patients in virological failure.

OBJECTIVES: To compare the antiviral efficacy of a salvage therapy combining lopinavir and amprenavir with 200 mg/d or 400 mg/d ritonavir, together with nucleoside reverse transcriptase inhibitors, over a 26-week period in HIV-infected patients in whom multiple antiretroviral regimens had failed. DESIGN: Phase IIb, randomized, open-label, multicentre trial. Patients were eligible if they had <500 CD4+ cells/mm3 and >4 log10 copies/ml HIV-RNA after treatment with at least two protease inhibitors (PIs) and one non-nucleoside reverse transcriptase inhibitor. RESULTS: At baseline (n=37), the median CD4+ cell count was 207/mm3 and the median plasma HIV-1 RNA level was 4.7 log10 copies/ml; the median number of PI mutations was seven and the median decrease in phenotypic susceptibility to lopinavir and amprenavir was 9.7 and 2.6, respectively. The mean number of antiretrovirals received prior to randomization was 7.7. The fall in the median HIV-1 RNA level at week 26 was -1.4 log10 copies/ml in the 200 mg/d ritonavir group and -2.5 log10 copies/ml in the 400 mg/d group (P=0.02). Viral load fell below 50 copies/ml in 32% and 61% of patients, respectively (P=0.07). After adjustment for the ritonavir dose, a smaller number of PI mutations was the only baseline characteristic associated with a better virological response at week 26. Amprenavir concentrations were significantly lower in presence of lopinavir. The lopinavir inhibitory quotient at week 6 correlated weakly with the change in the HIV-RNA level at week 26. CONCLUSION: Combination of amprenavir, lopinavir and 400 mg/d ritonavir shows significant virological efficacy without increased toxicity in HIV-infected patients in whom multiple antiretroviral regimens have failed.

Adult↗

[HIV infection].

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HIV Infections↗

Once-a-day highly active antiretroviral therapy in treatment-naive HIV-1-infected adults in Senegal.

OBJECTIVES: To study the effectiveness, adherence and tolerance of a once-a-day highly active antiretroviral therapy regimen in adults in Senegal. DESIGN AND METHODS: In a prospective, open-label one-arm study, 40 treatment-naive HIV-1-infected patients took the following three drugs once a day at bedtime: didanosine, lamivudine and efavirenz. The primary endpoint was the percentage of patients with plasma HIV-1 RNA below 500 copies/ml at 6 months. The analysis was done on an intent-to treat basis. RESULTS: Eighty-five per cent of patients were at Centers for Disease Control and Prevention stage B or C and the plasma HIV RNA level was 5.4 +/- 0.4 log(10) copies/ml at baseline. The percentage of patients with plasma HIV-1 RNA below 500 copies/ml at 6 months was 95% [95% confidence interval (CI), 83-99]. The proportions of patients with plasma HIV-1 RNA below 50 copies/ml at months 3, 6, 9, 12 and 15 were 26% (n = 39; 95% CI, 12-39), 78% (n = 40; 95% CI, 65-90), 70% (n = 40; 95% CI, 56-84), 77% (n = 39; 95% CI, 64-90) and 69% (n = 39; 95% CI, 55-84), respectively. The CD4 cell count was 164 +/- 75 x 106/l at baseline and increased by a mean of 199 +/- 101 x 106/l at month 15. Permanent treatment discontinuation was never necessary for serious adverse effects. Adherence was excellent, as shown by plasma drug concentrations and according to the results of the questionnaire. CONCLUSIONS: The once-daily regimen of didanosine, lamivudine and efavirenz was safe, easy-to-take and demonstrated strong antiretroviral and immunologic effects in African patients with advanced HIV infection.

Adult↗

Ku stimulation of DNA ligase IV-dependent ligation requires inward movement along the DNA molecule.

The DNA ligase IV.XRCC4 complex (LX) functions in DNA non-homologous-end joining, the main pathway for double-strand break repair in mammalian cells. We show that, in contrast to ligation by T4 ligase, the efficiency of LX ligation of double-stranded (ds) ends is critically dependent upon the length of the DNA substrate. The effect is specific for ds ligation, and LX/DNA binding is not influenced by the substrate length. Ku stimulates LX ligation at concentrations resulting in 1-2 Ku molecules bound per substrate, whereas multiply Ku-bound DNA molecules inhibit ds ligation. The combined footprint of DNA with Ku and LX bound is the sum of each individual footprint suggesting that the two complexes are located in tandem at the DNA end. Inhibition of Ku translocation by the presence of cis-platinum adducts on the DNA substrate severely inhibits ligation by LX. Fluorescence resonance energy transfer analysis using fluorophore-labeled Ku and DNA molecules showed that, as expected, Ku makes close contact with the DNA end and that addition of LX can disrupt this close contact. Finally, we show that recruitment of LX by Ku is impaired in an adenylation-defective mutant providing further evidence that LX interacts directly with the DNA end, possibly via the 5'-phosphate as shown for prokaryotic ligases. Taken together, our results suggest that, when LX binds to a Ku-bound DNA molecule, it causes inward translocation of Ku and that freedom to move inward on the DNA is essential to Ku stimulation of LX activity.

Antigens, Nuclear↗

High variability of plasma drug concentrations in dual protease inhibitor regimens.

Ritonavir (RTV) strongly increases the concentrations of protease inhibitors (PIs) in plasma in patients given a combination of RTV and another PI. This pharmacological interaction is complex and poorly characterized and shows marked inter- and intraindividual variations. In addition, RTV interacts differently with saquinavir (SQV), indinavir (IDV), amprenavir (APV), and lopinavir (LPV). In this retrospective study on 542 human immunodeficiency virus-infected patients, we compared inter- and intraindividual variability of plasma PI concentrations and correlations between the C(min) (minimum concentration of drug in plasma) values for RTV and the coadministered PI C(min) values. Mean RTV C(min)s are significantly lower in patients receiving combinations containing APV or LPV than in combinations with SQV or IDV. With the most common PI dose regimens (600 mg of IDV twice a day [BID], 800 mg of SQV BID, and 400 mg of LPV BID), the interindividual C(min) variability of patients treated with a PI and RTV seemed to be lower with APV and LPV than with IDV and SQV. As regards intraindividual variability, APV also differed from the other PIs, exhibiting lower C(min) variability than with the other combinations. Significant positive correlations between RTV C(min) and boosted PI C(min) were observed with IDV, SQV, and LPV, but not with APV. Individual dose adjustments must take into account the specificity the pharmacological interaction of each RTV/PI combination and the large inter- and intraindividual variability of plasma PI levels to avoid suboptimal plasma drug concentrations which may lead to treatment failure and too high concentrations which may induce toxicity and therefore reduce patient compliance.

Anti-HIV Agents↗

Predictors of the virological response to a change in the antiretroviral treatment regimen in HIV-1-infected patients enrolled in a randomized trial comparing genotyping, phenotyping and standard of care (Narval trial, ANRS 088).

OBJECTIVE: To identify predictors of the virological response to antiretroviral therapy in patients in whom initial therapy has failed. METHODS: The Narval trial was designed to compare phenotyping, genotyping and standard of care for the choice of antiretroviral therapy in patients in whom a protease inhibitor (PI)-containing regimen had failed. Virological success was defined as viral load below 200 copies/ml at week 12. Baseline variables including demographic, clinical and biological characteristics, HIV reverse transcriptase and protease mutations, the randomization arm, the drugs prescribed, as well as adherence to treatment and plasma concentrations of PIs and non-nucleoside reverse transcriptase inhibitors (NNRTIs) at week 12 were tested in the model. Variables that were significantly associated with virological success in univariate analysis were included in a logistic regression model. RESULTS: Five-hundred-and-forty-one patients were randomized. Virological success at week 12 was obtained in 200 patients. In multivariate analysis, the following factors were significantly associated with virological success: prescription of efavirenz to NNRTI-naive patients (OR=4.37; 95% CI: 2.76-6.90), randomization to the genotyping arm (OR=2.13, 1.20-3.79), prescription of lamivudine (OR=1.69, 1.01-2.83) and prescription of abacavir to abacavir-naive patients (OR=1.66, 1.02-2.72). Factors significantly associated with virological failure were prescription of nelfinavir (OR=0.30, 0.13-0.68), a high baseline viral load (OR=0.37, 0.28-0.50), the presence of at least five PI mutations (OR=0.42, 0.26-0.66), the presence of at least three thymidine analogue mutations (OR=0.61, 0.39-0.97) and at least 30 months of prior PI exposure (OR=0.64, 0.41-0.99). CONCLUSIONS: These results confirm that among heavily pretreated patients, prescription of efavirenz to NNRTI-naive patients is associated with a good virological response, while a high baseline viral load, a large number of PI mutations and nelfinavir prescription at baseline are associated with a poor virological response. Genotyping was found to be beneficial, while this was not the case for phenotyping. This work was presented at the XI International HIV Drug Resistance Workshop, Sevilla, Spain, July 3-6 2002 (Abstract N(o)133); and at the XIV International Conference on AIDS, Barcelona, Spain, July 7-11 2002 (Abstract N(o)ThOrB138).

Adult↗