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Background: Rilpivirine is widely prescribed in people living with HIV. Although trough plasma concentrations have been associated with virological response, the drug pharmacodynamics remain incompletely characterized.Objectives: To develop the first pharmacodynamic model of rilpivirine in order to establish the rilpivirine concentration-response relationship for future treatment optimization.Methods: A retrospective observational study was conducted in patients receiving the once-daily rilpivirine/tenofovir disoproxil fumarate/emtricitabine regimen. Individual rilpivirine trough plasma concentrations over time were predicted using a previous pharmacokinetic model. An established susceptible, infected, recovered model was used to describe HIV dynamics without assuming disease steady-state. Population analysis was performed with MONOLIX 2018 software. Simulations of the viral load evolution as a function of time and rilpivirine trough plasma concentration were performed.Results: Overall, 60 naive and 39 pre-treated patients were included with a follow-up ranging from 2 to 37 months. The final model adequately described the data and the pharmacodynamic parameters were estimated with a good precision. The population typical value of rilpivirine EC50 was estimated at 65 ng/mL. A higher infection rate constant of CD4 cells for HIV-1 was obtained in pre-treated patients. Consequently, the time to obtain virological suppression was longer in pre-treated than in naive patients.Conclusions: The concentration-response relationship of rilpivirine was satisfactorily described for the first time using an original population pharmacodynamic model. Simulations performed using the final model showed that the currently used 50 ng/mL rilpivirine trough plasma concentration efficacy target might need revision upwards, particularly in pre-treated patients. [ABSTRACT FROM AUTHOR]

Objectives As recommended by the French ANRS programme for the surveillance of HIV-1 resistance, we estimated the prevalence of transmitted drug resistance-associated mutations (RAMs) in antiretroviral-naive, chronically HIV-1-infected patients. Methods RAMs were sought in samples from 661 newly diagnosed HIV-1-infected patients in 2010/11 at 36 HIV clinical care centres. Weighted analyses were used to derive representative estimates of the percentage of patients with RAMs. Results At patient inclusion, the prevalence of virus with protease (PR) or reverse transcriptase (RT) RAMs was 9.0% (95% CI 6.8%–11.2%). No integrase RAMs were observed. The prevalences of protease inhibitor, nucleoside RT inhibitor and non-nucleoside RT inhibitor RAMs were 1.8%, 6.2% and 2.4%, respectively. Resistance to one, two and three classes of antiretroviral agent was observed in 7.9%, 0.9% and 0.2% of patients, respectively. The frequency of RAMs was higher in patients infected with B compared with non-B subtype virus (11.9% versus 5.1%, P = 0.003). Baseline characteristics (gender, age, country of transmission, CD4 cell count and viral load) were not associated with the prevalence of transmitted RAMs. However, men having sex with men (MSM) were more frequently infected with resistant virus than were other transmission groups (12.5% versus 5.8%, P = 0.003). Compared with the 2006/07 survey, the overall prevalence of resistance remained stable. However, a significant decrease in the frequency of virus with PR RAMs was observed in 2010/11 compared with the 2006/07 survey (1.8% versus 5.0%, P = 0.003). Conclusions In France in 2010/11, the global prevalence of transmitted drug-resistant variants was 9.0%, and the prevalence was stable compared with the 2006/07 survey. MSM and B subtype-infected patients are the groups with a higher prevalence of drug resistance. [ABSTRACT FROM PUBLISHER]

Objectives To estimate the prevalence of transmitted drug resistance mutations and non-B subtype circulation in antiretroviral-naive chronically HIV-1-infected patients in France. Methods Resistance mutations were sought in samples from 530 newly diagnosed HIV-1-infected patients from October 2006 to March 2007. Protease and reverse transcriptase mutations were identified from the 2007 Stanford Resistance Surveillance list. Results Reverse transcriptase and protease resistance mutations were determined in 466 patients with duration of seropositivity <5 years. 42% of patients were infected with non-B subtype strains (CRF02 18.3%). The overall prevalence of viruses with protease or reverse transcriptase mutations was 10.6% (95% confidence interval 6.7–16.3). The prevalence of protease inhibitor, nucleoside reverse transcriptase inhibitor and non-nucleoside reverse transcriptase inhibitor resistance-associated mutations was 4.7%, 5.8% and 2.8%, respectively. Frequency of resistance was not different in patients infected with B (9.5%) and non-B (CRF02 7.8% and other 11.2%) subtypes. Baseline characteristics such as gender, age, transmission group, country of transmission, disease stage, CD4 counts and viral load were not associated with the prevalence of transmitted drug resistance. Conclusions In France in 2006/2007, the prevalence of transmitted drug-resistant variants was 10.6%. Prevalence of transmitted drug resistance was comparable in B and non-B subtypes. Prevalence of non-B subtypes is still rising. [ABSTRACT FROM PUBLISHER]

We report a case of hepatitis B virus reactivation that occurred after immunosuppressive treatment in a hepatitis B surface antigen-negative patient with detectable antibodies to hepatitis B core antigen and hepatitis B surface antigen. Sequence analysis revealed an 11-bp insertion in the core promoter region of hepatitis virus DNA, creating a novel hepatocyte nuclear factor-i binding site. This led to enhanced viral replication and fulminant hepatitis. [ABSTRACT FROM AUTHOR]

Virologic studies of human immunodeficiency virus type 1--infected patients have investigated either the emergence of resistance mutations according to the treatment received (type I) or their effect on subsequent regimens (type II). Type I studies provide an estimation of the frequency distribution of mutations for a given duration of therapy, but the delay to emergence of these mutations cannot be assessed. We suggest using a nonparametric estimator that generalizes the Kaplan-Meier method to data from type II studies to estimate the time to occurrence of mutations. Patients had no treatment interruption before viral genotyping. Although the curves should be interpreted with caution, they provide useful information about the kinetics of the emergence of mutations. The method was applied to the emergence of thymidine analogue mutations in patients previously treated with zidovudine (ZDV) plus didanosine or zalcitabine. Although K70R has been described as the first mutation to appear in patients receiving ZDV monotherapy, the T215Y/F mutation appeared first in patients receiving dual-nucleoside combination therapy. [ABSTRACT FROM AUTHOR]

Presents a study which developed a method for the identification of non-B HIV virus type 1 subtypes with the use of drug resistance sequence data. Assessment of the molecular epidemiology of HIV virus type 1; Methodology; Results and discussion.

A combination of zidovudine, didanosine, and lamivudine was used to treat 10 patients with primary human immunodeficiency virus type 1 (HIV-1) infection 5–28 days after the onset of symptoms. When therapy began, the mean plasma HIV-1 RNA level was 5.31 ± 0.33 log10 copies/ mL and the mean CD4 T cell count was 630 ± 112 × 106/L. The plasma HIV-1 RNA level decreased rapidly, and levels dropped below the cutoff in each case after 108 ± 32 days. Lymph nodes from 5 patients were biopsied before therapy and during follow-up. Infectious HIV-1 could not be cultivated from any lymph node mononuclear cells taken on day 90, and HIV-1 RNA was at very low levels in lymph nodes after 1 year. In some cases, waning of the antibody response to HIV-1 was shown by Western blot after several months of undetectable plasma RNA. These data demonstrate that triple-drug therapy has a potent antiviral effect during primary HIV-1 infection. [ABSTRACT FROM PUBLISHER]

As lymphoid organs are the major reservoir of human immunodeficiency virus type 1 (HIV-l), the rates at which HIV-1 RNA decreases from the plasma and from a series of lymph node biopsies from 4 patients treated with a combination of zidovudine, didanosine, and lamivudine were measured. The concentrations of HTV-l RNA in the plasma and in lymph nodes declined exponentially, with mean half-lives of 1.88 ± 0.86 days for plasma and 6.01 ± 3.44 days for lymph nodes. These data show that most of the HIV-1 in lymphoid organs is due to the infection of new cells and demonstrate that a triple-drug combination is able to target this compartment. [ABSTRACT FROM PUBLISHER]

The activity of pefloxacin against Rickettsia conorii and R. rickettsii was determined by several methods. The mean survival time of embryonated eggs infected with R. conorii was increased by pefloxacin 50 micrograms/egg; plaque formation in Vero cells was inhibited by 1 mg/l. In a microplate assay, the MIC of pefloxacin was 0.5 mg/l for R. conorii and 1 mg/l for R. rickettsii. The results support the use of pefloxacin in treating spotted fever rickettsioses. [ABSTRACT FROM AUTHOR]

Human immunodeficiency virus type 1 (HIV-1) RNA was measured in total lymph node (LN) tissue and isolated LN mononuclear cells (LNMC) in sequential LN biopsy samples from 1 patient with primary HIV-1 infection and from 5 previously untreated patients with chronic disease. HIV-1 RNA levels were an average of 210-fold higher in total LN tissue compared with levels in LNMC, even during primary infection, when circulating antibodies were absent. After the patients were treated with a three- or four-drug regimen, total HIV-1 RNA decreased exponentially in total LN tissue and in LNMC (mean half-lives of 8.5 ± 1.8 and 7.9 ± 2.2 days, respectively). In addition, the evolution of the infectious virus in LNMC was analyzed for the 5 patients with chronic disease: Titers decreased, with a mean half-life of 7.5 ± 2.3 days. Extracellular virions are the most important virus compartments in LNs; however, they exhibit the same dynamics as virions situated in LNMC, with a mean virus decay half-life of ∼1 week. [ABSTRACT FROM PUBLISHER]

The article discusses a case report of a 52-year-old woman who presented with a skin tumour on the groin, diagnosed as human papillomavirus (HPV) type-16 induced skin squamous cell carcinoma (SCC). Topics discussed include symptoms of the disease manifested in the patient, medical tests conducted, and treatment applied.

: Objectives We studied gp41 mutations associated with failing enfuvirtide salvage therapy. : Methods This multicentre study involved patients with HIV-1 plasma viral load (pVL) > 5000 copies/mL after at least 3 months of uninterrupted enfuvirtide therapy and with plasma samples available at inclusion (T0), at initial enfuvirtide failure (T1) and at last follow-up visit during continued failing enfuvirtide therapy (T2). The HR-1 and HR-2 domains of the gp41 gene were sequenced at T0, T1 and T2. : Results Ninety-nine patients were enrolled. At baseline, the median pVL and CD4 cell count were 5.1 log copies/mL and 72 cells/mm3, respectively. Based on the ANRS Resistance Group algorithm, the proportion of patients harbouring viruses with enfuvirtide resistance mutations increased significantly between T0 and T1. In the HR-1 domain, the V38A/M, Q40H, N42T, N43D and L45M mutations wereselected (P < 0.02). In the HR-2 domain, no mutations were significantly selected during the follow-up. None of the mutations was associated with a CD4 cell count increment. : Conclusions Mutations selected during failing enfuvirtide salvage therapy are mainly located in the HR-1 domain of the gp41 gene, between codons 38 and 45. No mutations were associated with an increase in the CD4 cell count. [ABSTRACT FROM AUTHOR]

Background We developed clinically relevant genotypic scores for resistance to fosamprenavir/ritonavir in HIV-1 protease inhibitor (PI)-experienced patients. Methods PI-experienced patients with virological failure receiving fosamprenavir/ritonavir as the sole PI for at least 3 months and with detectable fosamprenavir plasma levels were included. The impact of baseline protease mutations on virological response (VR, i.e. decrease in plasma HIV-1 RNA between baseline and month 3) was analysed using the Mann–Whitney test. Mutations with prevalence >10% and P value Results In the 73 patients included, the median baseline HIV-1 RNA was 4.6 log10 copies/mL (range: 2.7–6.9) and the mean decrease at month 3 was −1.07 ± 1.40 log10 copies/mL. Ninety per cent of the patients were infected by HIV-1 subtype B variants. Two fosamprenavir/ritonavir mutation scores were constructed: score A (L10F/I/V + L33F + M36I + I54L/M/V/A/T/S + I62V + V82A/F/C/G + I84V + L90M) was based only on mutations associated with a worse VR, whereas score B (L10FIV + L33F + M36I + I54L/M/V/A/T/S + A71V − V77I − N88S + L90M) also took into account favourable mutations. Both scores were independent predictors of VR, however, co-administration of tenofovir was associated with a worse VR and the presence of the N88S protease mutation and co-administration of enfuvirtide with a better VR. Conclusions These clinically validated mutation scores should be of interest for the clinical management of PI-experienced patients. The fosamprenavir/ritonavir score A was introduced in the 2006 ANRS algorithm along with isolated mutations I50V and V32I + I47V. [ABSTRACT FROM AUTHOR]