Fabrice Carrat

Bio: Fabrice Carrat is an academic researcher from University of Paris. The author has contributed to research in topics: Population & Medicine. The author has an hindex of 67, co-authored 394 publications receiving 18450 citations. Previous affiliations of Fabrice Carrat include Sorbonne & French Institute of Health and Medical Research.

Time Lines of Infection and Disease in Human Influenza: A Review of Volunteer Challenge Studies

Abstract: The dynamics of viral shedding and symptoms following influenza virus infection are key factors when considering epidemic control measures. The authors reviewed published studies describing the course of influenza virus infection in placebo-treated and untreated volunteers challenged with wild-type influenza virus. A total of 56 different studies with 1,280 healthy participants were considered. Viral shedding increased sharply between 0.5 and 1 day after challenge and consistently peaked on day 2. The duration of viral shedding averaged over 375 participants was 4.80 days (95% confidence interval: 4.31, 5.29). The frequency of symptomatic infection was 66.9% (95% confidence interval: 58.3, 74.5). Fever was observed in 37.0% of A/H1N1, 40.6% of A/H3N2 (p = 0.86), and 7.5% of B infections (p = 0.001). The total symptoms scores increased on day 1 and peaked on day 3. Systemic symptoms peaked on day 2. No such data exist for children or elderly subjects, but epidemiologic studies suggest that the natural history might differ. The present analysis confirms prior expert opinion on the duration of viral shedding or the frequency of asymptomatic influenza infection, extends prior knowledge on the dynamics of viral shedding and symptoms, and provides original results on the frequency of respiratory symptoms or fever.

Pegylated interferon alfa-2b vs standard interferon alfa-2b, plus ribavirin, for chronic hepatitis C in HIV-infected patients: a randomized controlled trial.

Abstract: ContextTreatment of chronic hepatitis C virus (HCV) infection in human immunodeficiency virus (HIV)–infected patients is a growing concern. Most data on the virologic efficacy and safety of the combination of peginterferon alfa-2b and ribavirin in coinfected patients come from uncontrolled studies.ObjectiveTo study the safety and efficacy of peginterferon alfa-2b plus ribavirin vs standard interferon alfa-2b plus ribavirin in HIV-HCV coinfected patients.Design and SettingsA multicenter, randomized, parallel-group, open-label trial. Patients were enrolled from February 2000 to February 2002 and followed up for 72 weeks.PatientsFour hundred twelve HIV-HCV coinfected patients with detectable serum HCV-RNA, abnormal liver histology, a CD4 cell count of at least 200 × 106/L, and stable plasma HIV-RNA.InterventionTreatment with ribavirin 400 mg twice a day, orally, plus either peginterferon alfa-2b (1.5 μg/kg subcutaneous injection once a week) or standard interferon alfa-2b (3 million units of subcutaneous injection 3 times a week) for 48 weeks.Main Outcome MeasuresSustained virologic response, defined by undetectable serum HCV-RNA at week 72.ResultsMore patients had sustained virologic responses in the peginterferon group than in the standard interferon group (27% vs 20%, P = .047). This difference between the treatments was found in patients with HCV genotype 1 or 4 infection (17% for peginterferon vs 6% for standard interferon, P = .006) but was not found in patients with HCV genotype 2, 3, or 5 (44% for peginterferon vs 43% for standard interferon, P = .88). Together, a decline in HCV-RNA of less than 2 log10 from baseline and detectable serum HCV-RNA at week 12 predicted 99% of treatment failures. Histologic activity diminished and fibrosis stabilized in virologic responders. The 2 regimens showed similar tolerability although dose modifications for clinical and biological events were more frequent with peginterferon. Eleven cases of pancreatitis or symptomatic hyperlactatemia were observed, all in patients receiving didanosine-containing antiretroviral regimens.ConclusionIn combination with ribavirin, treatment with peginterferon alfa-2b is more effective than standard interferon alfa-2b for HCV infection in HIV-infected patients.

Regulatory T-cell responses to low-dose interleukin-2 in HCV-induced vasculitis.

Abstract: Background Patients with vasculitis induced by the hepatitis C virus (HCV) have reduced levels of regulatory T cells (Tregs). Resolution of HCV infection correlates with cure of vasculitis and the recovery of Treg levels. We reasoned that interleukin-2, a cytokine that promotes Treg survival and function, could be beneficial for patients with vasculitis that is resistant to HCV therapy. Methods We investigated the safety and immunologic effects of the administration of low-dose interleukin-2 in a prospective open-label, phase 1–phase 2a study. Ten patients with HCV-induced vasculitis that was refractory to conventional antiviral therapy, rituximab therapy, or both and who were not receiving glucocorticoid or immunosuppressant therapy received one course of interleukin-2 (1.5 million IU per day) for 5 days, followed by three 5-day courses of 3 million IU per day at weeks 3, 6, and 9. Both the safety of the treatment and its effectiveness were evaluated, the latter by monitoring the Treg response and the cl...

Microenvironmental regulation of tumor progression and metastasis.

Abstract: Cancers develop in complex tissue environments, which they depend on for sustained growth, invasion and metastasis. Unlike tumor cells, stromal cell types within the tumor microenvironment (TME) are genetically stable and thus represent an attractive therapeutic target with reduced risk of resistance and tumor recurrence. However, specifically disrupting the pro-tumorigenic TME is a challenging undertaking, as the TME has diverse capacities to induce both beneficial and adverse consequences for tumorigenesis. Furthermore, many studies have shown that the microenvironment is capable of normalizing tumor cells, suggesting that re-education of stromal cells, rather than targeted ablation per se, may be an effective strategy for treating cancer. Here we discuss the paradoxical roles of the TME during specific stages of cancer progression and metastasis, as well as recent therapeutic attempts to re-educate stromal cells within the TME to have anti-tumorigenic effects.