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Featured researches published by A. Pivert.


Gut | 2007

Rapid and early virological response to chronic hepatitis C treatment with IFN α2b or PEG-IFN α2b plus ribavirin in HIV/HCV co-infected patients

Christopher Payan; A. Pivert; Patrice Morand; Samira Fafi-Kremer; Fabrice Carrat; Stanislas Pol; Patrice Cacoub; Christian Perronne; Françoise Lunel

Background and aims: An algorithm based on a 2 log10 decline in hepatitis C virus (HCV) RNA at week (W) 12 has been proposed in US and European recommendations for the management of patients with chronic hepatitis C treated with pegylated-interferon and ribavirin. Methods: We examined rapid virological response (RVR; at W2 and W4 after the initiation of therapy) in HIV/HCV co-infected patients. Using HCV RNA measurements (Versant HCV RNA 3.0, Cobas Amplicor HCV 2.0), RVR was studied in 323 patients from the ANRS HC02 RIBAVIC trial, comparing interferon α2b 3 MU ×3/week with pegylated interferon α2b 1.5 μg/kg/week, each combined with ribavirin 800 mg/day over 48 weeks. Results: The best positive and negative predictive values of sustained virological response (SVR) were obtained with an undetectable HCV RNA at W4 (97%) and with more than a 2 log10 decrease at W12 (99%), respectively. Prediction of non-SVR was obtained in all patients by using HCV RNA cut-off levels above 460 000 IU/ml at W4 and above 39 000 UI/ml at W12 irrespective of the HCV genotype and arm of treatment. Conclusion: We propose a new algorithm based on RVR thresholds using HCV RNA that allows for excellent prediction of non-SVR as early as W4.


Journal of Clinical Virology | 2010

Resolution of chronic hepatitis Delta after 1 year of combined therapy with pegylated interferon, tenofovir and emtricitabine.

Wael Mansour; Alexandra Ducancelle; Frédéric Le Gal; Hélène Le Guillou-Guillemette; Pierre Abgueguen; A. Pivert; Paul Calès; Emmanuel Gordien; Françoise Lunel

BACKGROUND Hepatitis Delta virus (HDV) Infection has a worldwide distribution, with approximately 20 millions infected persons. Interferon (IFN) is the only approved drug for the treatment of HDV infection which is still a difficult to treat disease. OBJECTIVES To report a successful treatment of a patient with a chronic severe hepatitis Delta using combination therapy with Pegylated interferon (PegIFN), Tenofovir disoproxil fumarate (TDF) and Emtricitabine (FTC). STUDY DESIGN The patient, a 47 years -old male patient, originating from Dagestan (East Asia), suffered of chronic hepatitis Delta infection. The patient was HBsAg, HBeAg, and anti-Delta Ab (IgG) positive. Serum HBV-DNA level was elevated (more than 9 log UI/mL). Serum HDV-RNA level was up to 5.6 log (copies/ml). Genotypes HBV/D and HDV-1 were demonstrated. The liver histology revealed chronic active hepatitis (Metavir score: A2F2). The treatment was started with PegIFN (180 microg/week) for two months and then TDF (300 mg/day) (combined later with FTC) was added. RESULTS Sustained response was obtained after 10 months of treatment and was accompanied by the clearance of serum hepatitis B virus surface antigen with seroconversion to anti-HBs. CONCLUSION This case report suggests that Delta infection may co-exist with high replicative HBV infection and that combination therapy with PegIFN and nucleoside/tide analogues seems to be more effective than IFN alone. Given that only a single case is reported, further studies including more patients are warranted.


Journal of Medical Virology | 2015

Correlation between the promoter basal core and precore mutations and HBsAg quantification in French blood donors infected with hepatitis B virus

A. Pivert; A. Servant-Delmas; Françoise Lunel-Fabiani; H. Le Guillou-Guillemette; Syria Laperche; A. Ducancelle

Hepatitis B virus (HBV) basal core promoter (BCP) and precore (PC) mutations, HBV viral load and HBV surface antigen (HBsAg) quantitation were screened to assess correlations between these HBV markers in asymptomatic chronic hepatitis B carriers in France. From January 2006 to July 2007, 200 sera were collected from patients who were discovered to be HBsAg‐positive when they volunteered to give blood. Direct sequencing of precore/core gene was used to detect A1762T/G1764A mutations in the BCP and G1896A in the PC region. HBV viral load and HBsAg were quantified with two commercials assays. The prevalence of the BCP and PC mixed/mutants were 37% and 60% respectively (P = 0.0001). HBV DNA level and HBsAg titer were significantly lower in subjects harboring the mixed/mutant PC virus compared to those infected by the wild phenotype. No significant difference was observed in HBV viral loads of blood donors infected by wild or mixed/mutant BCP viruses. Mutant or mixed PC virus was associated with male gender, HBeAb‐positive status and HBV/D and HBV/E genotypes. BCP mutations were associated with age, and both HBV/A‐HBV/E genotypes.The genetic properties of HBV in this cohort showed that most of the blood donors had a negative HBeAg serological status and harbored the PC mutant phenotype in combination with low levels of both HBV DNA and HBsAg. As the study was conducted in healthy subjects who could be considered as asmptomatic carriers, these results suggest a possible protective effect of the G1896A mutation against severe liver lesions. J. Med. Virol. 87:529–535, 2015.


Journal of Clinical Microbiology | 2006

Comparison of Serum Hepatitis C Virus (HCV) RNA and Core Antigen Levels in Patients Coinfected with Human Immunodeficiency Virus and HCV and Treated with Interferon plus Ribavirin

A. Pivert; C. Payan; Patrice Morand; Samira Fafi-Kremer; Juliette Deshayes; Fabrice Carrat; Stanislas Pol; Patrice Cacoub; Christian Perronne; Françoise Lunel

ABSTRACT Trak-C (Ortho-Clinical Diagnostics) is an enzyme-linked immunosorbent assay-based method capable of quantifying hepatitis C virus (HCV) core antigen (CA) in serum and could be an alternative to molecular detection and quantification of HCV RNA. We have evaluated the Trak-C assay in comparison with an HCV RNA quantitative assay (Versant HCV v3.0; Bayer Diagnostics) in the follow-up of 348 treated, human immunodeficiency virus (HIV)/HCV-coinfected patients included in the ANRS HC02 RIBAVIC trial. ANRS HC02 RIBAVIC is a therapeutic, multicenter, randomized protocol comparing the efficacy of alpha interferon 2b (IFN-α2b) (3 million units three times a week)-ribavirin (800 mg/day) to that of pegylated IFN-α2b (1.5 μg/kg of body weight/week)-ribavirin (800 mg/day) during 48 weeks of treatment of HIV/HCV-coinfected patients naïve to HCV treatment. Patients were assessed for virological analysis at day 0 and weeks 4, 12, 24, 48, and 72. Correlation of HCV RNA and HCV CA at the initiation of treatment was excellent (r = 0.92). HCV RNA and CA kinetics were similar during follow-up of HCV treatment from day 0 to week 72 whatever the group of response and genotype. The positive and negative predictive values of response to the treatment at week 4 were 59 and 94%, respectively, for HCV RNA load reduction of >2 log and 54 and 94%, respectively, for HCV CA below the threshold value (4.18 log10 pg/ml · 104). Trak-C, a new assay able to quantify CA in HIV/HCV-coinfected patients, correlates well with quantitative HCV RNA assays and is cheaper and easier to perform than molecular technology. HCV CA could be a valuable alternative test for therapeutic follow-up of coinfected patients treated with IFN plus ribavirin in developing countries.


Journal of Infection | 2015

Home-based urinary HPV DNA testing in women who do not attend cervical cancer screening clinics.

Alexandra Ducancelle; Justine Reiser; A. Pivert; Hélène Le Guillou-Guillemette; Anne Sophie Le Duc-Banaszuk; Françoise Lunel-Fabiani

In France, cervical cancer screening is currently based on cytological examination of a Pap smear for women aged 25 to 65, but screening coverage is unsatisfactory. Previous studies have shown that self-sampling for human papillomavirus (HPV) testing increases rates of compliance. With this purpose in mind, we performed the CapU study to evaluate the acceptance of a urinary HPV test. Letters proposing a new cervical cancer screening method using at-home urine self-sampling were sent to 5000 women aged 40-65 years who had not had a Pap smear over the past three years. The participating patients had to send their urine samples to the Angers Hospital Virology Laboratory for analysis using real-time PCR. Of the 771 samples received, 687 were analyzed. High-risk HPV were detected in 29 women. In follow-up, 28 women with positive urinary HPV results had a Pap smear or colposcopy done. The cytological results showed nine abnormal Pap smears, among which histology studies confirmed three cases of cervical intraepithelial neoplasia grade III lesions. Our study shows that urinary HPV testing may be pertinent to women who do not have cervical Pap smears done and lead to the diagnosis of high-grade cervical lesions.


Journal of Gastroenterology and Hepatology | 2016

Different precore/core mutations of hepatitis B interact with, limit or favor liver fibrosis severity

Alexandra Ducancelle; A. Pivert; S. Bertrais; Jérôme Boursier; Viorica Balan; Pascal Veillon; Hélène Le Guillou-Guillemette; Vincent Thibault; Sandrine Castelain; Bénédicte Roquebert; Marianne Coste-Burel; Vincent Mackiewicz; Evelyne Schvoerer; Sylvie Larrat; Sarah Maylin; Sophie Alain; V. Loustaud-Ratti; Emmanuel Gordien; Joël Gozlan; Véronique Brodard; Stéphane Chevaliez; Paul Calès; Françoise Lunel-Fabiani

The impact of basal core promoter (BCP) and precore (PC) mutants of the hepatitis B virus (HBV) on liver disease severity remains controversial. The aim of the present study was to screen BCP and PC mutations in 252 HBV surface antigen (HBsAg) positive carriers in France and to assess relationships between these mutations and severe fibrosis.


Journal of Clinical Virology | 2015

Identification of a duplicated V3 domain in NS5A associated with cirrhosis and hepatocellular carcinoma in HCV-1b patients

H. Le Guillou-Guillemette; Alexandra Ducancelle; S. Bertrais; Christophe Lemaire; A. Pivert; Pascal Veillon; E. Bouthry; Sophie Alain; Vincent Thibault; Florence Abravanel; Arielle R. Rosenberg; Cécile Henquell; Elisabeth André-Garnier; O. Petsaris; Sonia Vallet; J.-B. Bour; Yazid Baazia; Pascale Trimoulet; Patrice André; Catherine Gaudy-Graffin; Dominique Bettinger; Sylvie Larrat; Anne Signori-Schmuck; Henia Saoudin; Bruno Pozzetto; Gisèle Lagathu; S. Minjolle-Cha; Françoise Stoll-Keller; Jean-Michel Pawlotsky; Jacques Izopet

BACKGROUND The NS5A protein of the hepatitis C virus has been shown to be involved in the development of hepatocellular carcinoma. OBJECTIVES In a French multicenter study, we investigated the clinical and epidemiological features of a new HCV genotype 1b strain bearing a wide insertion into the V3 domain. STUDY DESIGN We studied NS5A gene sequences in 821 French patients infected with genotype 1b HCV. RESULTS We identified an uncharacterized V3 insertion without ORF disruption in 3.05% of the HCV sequences. The insertion comprised 31 amino-acids for the majority of patients; 3 patients had 27 amino-acids insertions and 1 had a 12 amino-acids insertion. Sequence identity between the 31 amino-acids insertions and the V3 domain ranged from 48 to 96% with E-values above 4e(-5), thus illustrating sequence homology and a partial gene duplication event that to our knowledge has never been reported in HCV. Moreover we showed the presence of the duplication at the time of infection and its persistence at least during 12 years in the entire quasispecies. No association was found with extrahepatic diseases. Conversely, patients with cirrhosis were two times more likely to have HCV with this genetic characteristic (p=0.04). Moreover, its prevalence increased with liver disease severity (from 3.0% in patients without cirrhosis to 9.4% in patients with both cirrhosis and HCC, p for trend=0.045). CONCLUSIONS We identified a duplicated V3 domain in the HCV-1b NS5A protein for the first time. The duplication may be associated with unfavorable evolution of liver disease including a possible involvement in liver carcinogenesis.


Journal of Clinical Microbiology | 2013

Multicenter Quality Control of Hepatitis C Virus Protease Inhibitor Resistance Genotyping

Sophie Vallet; Sylvie Larrat; Syria Laperche; Hélène Le Guillou-Guillemette; Florence Legrand-Abravanel; Françoise Bouchardeau; A. Pivert; Cécile Henquell; Audrey Mirand; Elisabeth André-Garnier; Valérie Giordanengo; Gisèle Lagathu; Vincent Thibault; Caroline Scholtes; Evelyne Schvoerer; Catherine Gaudy-Graffin; Sarah Maylin; Pascale Trimoulet; Etienne Brochot; Sébastien Hantz; Joël Gozlan; Anne-Marie Roque-Afonso; Patrick Soussan; Jean-Christophe Plantier; Charlotte Charpentier; Stéphane Chevaliez; Philippe Colson; Vincent Mackiewicz; Lina Aguilera; Sylvain Rosec

ABSTRACT Hepatitis C virus (HCV) protease inhibitor resistance-associated substitutions are selected during triple-therapy breakthrough. This multicenter quality control study evaluated the expertise of 23 French laboratories in HCV protease inhibitor resistance genotyping. A panel of 12 well-defined blinded samples comprising two wild-type HCV strains, nine transcripts from synthetic NS3 mutant samples or from clinical strains, and one HCV RNA-negative sample was provided to the participating laboratories. The results showed that any laboratory with expertise in sequencing techniques should be able to provide reliable HCV protease inhibitor resistance genotyping. Only a 0.7% error rate was reported for the amino acid sites studied. The accuracy of substitution identification ranged from 75% to 100%, depending on the laboratory. Incorrect results were mainly related to the methodology used. The results could be improved by changing the primers and modifying the process in order to avoid cross-contamination. This study underlines the value of quality control programs for viral resistance genotyping, which is required prior to launching observational collaborative multicenter studies on HCV resistance to direct-acting antiviral agents.


PLOS ONE | 2017

Natural non-homologous recombination led to the emergence of a duplicated V3-NS5A region in HCV-1b strains associated with hepatocellular carcinoma

Hélène Le Guillou-Guillemette; A. Pivert; Elise Bouthry; Cécile Henquell; O. Petsaris; Alexandra Ducancelle; Pascal Veillon; Sophie Vallet; Sophie Alain; Vincent Thibault; Florence Abravanel; Arielle A. Rosenberg; Elisabeth André-Garnier; Jean-Baptiste Bour; Yazid Baazia; Pascale Trimoulet; Patrice André; Catherine Gaudy-Graffin; Dominique Bettinger; Sylvie Larrat; Anne Signori-Schmuck; Henia Saoudin; Bruno Pozzetto; Gisèle Lagathu; Sophie Minjolle-Cha; Françoise Stoll-Keller; Jean-Michel Pawlotsky; Jacques Izopet; C. Payan; Françoise Lunel-Fabiani

Background The emergence of new strains in RNA viruses is mainly due to mutations or intra and inter-genotype homologous recombination. Non-homologous recombinations may be deleterious and are rarely detected. In previous studies, we identified HCV-1b strains bearing two tandemly repeated V3 regions in the NS5A gene without ORF disruption. This polymorphism may be associated with an unfavorable course of liver disease and possibly involved in liver carcinogenesis. Here we aimed at characterizing the origin of these mutant strains and identifying the evolutionary mechanism on which the V3 duplication relies. Methods Direct sequencing of the entire NS5A and E1 genes was performed on 27 mutant strains. Quasispecies analyses in consecutive samples were also performed by cloning and sequencing the NS5A gene for all mutant and wild strains. We analyzed the mutant and wild-type sequence polymorphisms using Bayesian methods to infer the evolutionary history of and the molecular mechanism leading to the duplication-like event. Results Quasispecies were entirely composed of exclusively mutant or wild-type strains respectively. Mutant quasispecies were found to have been present since contamination and had persisted for at least 10 years. This V3 duplication-like event appears to have resulted from non-homologous recombination between HCV-1b wild-type strains around 100 years ago. The association between increased liver disease severity and these HCV-1b mutants may explain their persistence in chronically infected patients. Conclusions These results emphasize the possible consequences of non-homologous recombination in the emergence and severity of new viral diseases.


Journal of Hepatology | 2011

802 CHARACTERIZATION OF A MAJOR V3 DUPLICATION IN THE NS5A REGION OF GENOTYPE IB HCV BY QUASISPECIES ANALYSIS IN A FRENCH MULTICENTER STUDY

H. Le Guillou-Guillemette; E. Bouthry; A. Pivert; Arielle R. Rosenberg; Sophie Alain; Vincent Thibault; Florence Abravanel; S. Minjolle-Cha; Elisabeth André-Garnier; D. Moradpour; Cécile Henquell; J.-B. Bour; O. Petsaris; Yazid Baazia; Patrice André; Pascale Trimoulet; C. Gaudy-Graffln; Dominique Bettinger; Henia Saoudin; Evelyne Schvoerer; Jacques Izopet; C. Payan; Françoise Lunel-Fabiani

4. the dose-dependent neutralization of HCV infection by CD81 specific antibodies and convalescent serum from a recovered HCV genotype 1 patient. Conclusion: This new ex vivo model allows to support HCV replication. It provides a powerful tool for studying the viral life cycle, the dynamics of viral spread in the native tissue and for evaluating the potency and resistance profile of new antiviral therapies.

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C. Payan

Scripps Research Institute

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Pascale Trimoulet

Université Bordeaux Segalen

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