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2.
Gastroenterology ; 154(4): 976-988.e4, 2018 03.
Article in English | MEDLINE | ID: mdl-29146520

ABSTRACT

BACKGROUND & AIMS: Little is known about substitutions that mediate resistance of hepatitis C virus (HCV) to direct-acting antivirals (DAAs), due to the small number of patients with treatment failure in approval studies. It is important to identify resistance patterns to select effective salvage treatments. METHODS: We performed a comprehensive analysis for resistance-associated substitutions (RASs) in HCV genes (nonstructural protein [NS]3, NS5A, NS5B) targeted by DAAs. We compared NS3, NS5A, and NS5B sequences from 626 patients in Europe with DAA failure with sequences from 2322 DAA-naïve patients, infected with HCV genotypes 1 to 4. We considered RASs to be relevant if they were associated with DAA failure in patients or conferred a greater than twofold change in susceptibility compared with a reference strain in in vitro replicon assays. Data were collected on pretreatment status, DAA regimen, the treatment initiation date and duration, and virologic response. Patients who received at least 4 weeks of antiviral treatment were included in the analysis. RESULTS: RASs in NS3 associated with simeprevir or paritaprevir failure include R155K and D168E/V. In addition, several RASs were specifically associated with failure of simeprevir (Q80K/R in patients with genotype 1a or 4) or paritaprevir (Y56H in combination with D168V in patients with genotype 1b). Y93H in NS5A was the RAS most frequently associated with failure of daclatasvir, ledipasvir, or ombitasvir in patients with genotype 1b infection, and L31M was associated with failure of daclatasvir or ledipasvir, but not ombitasvir. RASs in NS5A were heterogeneous among patients with HCV genotype 1a or genotype 4 infections. In patients with HCV genotype 3, Y93H was associated with resistance to daclatasvir, but no RASs were associated with ledipasvir failure, pointing to a limited efficacy of ledipasvir in patients with genotype 3. Among patients failed by sofosbuvir-containing regimens, L159F was enriched in patients with genotype 1b (together with C316N) or genotype 3 infection, whereas the RAS S282T was rarely observed. CONCLUSIONS: We compared RASs in NS3, NS5A, and NS5B among patients failed by DAA therapy. Theses varied with the HCV genotype and subtype, and the different drug classes. These findings might be used to select salvage therapies.


Subject(s)
Antiviral Agents/therapeutic use , Drug Resistance, Viral/genetics , Hepacivirus/drug effects , Hepatitis C, Chronic/drug therapy , Protease Inhibitors/therapeutic use , Viral Nonstructural Proteins/antagonists & inhibitors , Antiviral Agents/adverse effects , Drug Substitution , Drug Therapy, Combination , Europe , Genotype , Hepacivirus/enzymology , Hepacivirus/genetics , Hepatitis C, Chronic/diagnosis , Hepatitis C, Chronic/virology , Humans , Phenotype , Protease Inhibitors/adverse effects , Retreatment , Retrospective Studies , Time Factors , Treatment Failure , Viral Nonstructural Proteins/genetics , Viral Nonstructural Proteins/metabolism
3.
Infection ; 46(3): 405-408, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29478091

ABSTRACT

PRUPOSE: To examine current risk behavior, awareness, experience, and attitudes towards pre-exposure-prophylaxis (PrEP), and to estimate a potential impact on the prevention of HIV transmission among HIV-negative MSM in Germany. PrEP was not officially licensed at the time of survey. METHODS: Web-based questionnaire from 03-06/2016. Potential participants were informed through social media, flyers, and advertisements. Risk contacts were defined as unprotected sexual intercourse under the influence of recreational drugs in the past 6 months. RESULTS: In total, 1208 subjects participated, 342 subjects were excluded for being HIV-infected or non-MSM, leaving 866 subjects to be evaluated in this analysis. Mean age was 37.0 ± 10.4 years. 593 participants (68.5%) were tested for HIV within the past 12 months. A total of 206 STDs in the past 6 months were reported by 144 (16.6%). Aware of PrEP was 748 (86.4%) respondents, while 65.1% reported willingness to use it. Risk behavior was significantly associated with higher PrEP acceptance (OR 2.90, 95% CI 2.14-3.90), as was a history of STDs (OR 1.85, 95% CI 1.17-2.91). The use of condoms would forgo 52.3% of subjects if taking PrEP. Sixty-five respondents (7.5%) reported PrEP use. Only 19 (29.2%) had accessed PrEP under medical supervision. PrEP use was reported by 14.8% with > 5 risk contacts in the past 6 months, compared to 6.3% with one risk contact (p < 0.001). CONCLUSION: We found a high PrEP awareness and acceptance, especially among subgroups of MSM at highest risk of HIV infection. Structured access and availability of PrEP to this population may have an important impact on the HIV epidemic in Germany.


Subject(s)
HIV Infections/psychology , Health Knowledge, Attitudes, Practice , Homosexuality, Male/psychology , Pre-Exposure Prophylaxis , Adult , Germany , Humans , Male , Middle Aged , Surveys and Questionnaires
4.
Infection ; 46(3): 341-347, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29460228

ABSTRACT

PURPOSE: Sexually transmitted infections (STIs) occur frequently in risk populations. Hereby, the role of screening-programmes remains controversial. Our study aimed to determine the prevalence of STI infections in HIV-positive men-who-have-sex-with-men (MSM). METHODS: We enrolled asymptomatic, HIV-MSM in a prospective cross-sectional study from February to August 2016 at seven German HIV-centres. All subjects were screened for Treponema-pallidum (TP) and hepatitis-B/C-infection. HIV RNA and screening for oral, rectal and urethral colonisation by Chlamydia-trachomatis (CT) and/or Neisseria-gonorrhoeae (NG) was performed. All subjects were asked to complete a sexual-risk-behaviour-questionnaire. RESULTS: In total, 296 subjects with a median age of 43.2 (36.2-49.5) years were enrolled; 99.3% were on ART for 5.5 (2.3-11.2) years. HIV RNA was < 50 copies/mL in 93.6%. Active syphilis infection was found in 5.0% of all patients, whereas 55.4% had history of infection. HCV seropositivity was found in 33 patients (13.2%) and positive HCV RNA was available in 39.4%. 66/294 (22.5%) showed negative anti-HBs-antibodies, indicating lack of immunity. Overall, 40/296 (13.5%) had positive CT/NG swabs (CT in 8.8%; 7.3% anorectal, 1.7% oropharyngeal, 1.0% urethral and NG in 6.8%; 4.5% anal, 2.0% oropharyngeal, 1.4% urethral). Time since HIV infection < 7 years (OR 2.6 (1.2-5.5); p = 0.012), the use of inhalative nitrites ("poppers") (OR 2.8 (1.3-5.9; p = 0.008) and reporting unprotected intercourse with > 20 partners within the last 6 months [OR 3.0 (1.2-7.8); p = 0.003] were significantly associated in multivariate analysis. CONCLUSION: We found high numbers of asymptomatic syphilis, hepatitis-C and CT/NG infections in HIV-MSM, remarkably in patients with shorter duration of HIV-infection with more sexual partners within last 6 months.


Subject(s)
Asymptomatic Infections/epidemiology , HIV Seropositivity/epidemiology , Sexual Behavior , Sexual and Gender Minorities/statistics & numerical data , Sexually Transmitted Diseases/epidemiology , Adult , Cross-Sectional Studies , Germany/epidemiology , Humans , Male , Middle Aged , Prevalence , Prospective Studies , Sexually Transmitted Diseases/etiology
5.
Int J Mol Sci ; 17(6)2016 Jun 13.
Article in English | MEDLINE | ID: mdl-27304952

ABSTRACT

Hepatitis C virus (HCV) substantially affects lipid metabolism, and remodeling of sphingolipids appears to be essential for HCV persistence in vitro. The aim of the current study is the evaluation of serum sphingolipid variations during acute HCV infection. We enrolled prospectively 60 consecutive patients with acute HCV infection, most of them already infected with human immunodeficiency virus (HIV), and serum was collected at the time of diagnosis and longitudinally over a six-month period until initiation of antiviral therapy or confirmed spontaneous clearance. Quantification of serum sphingolipids was performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Spontaneous clearance was observed in 11 out of 60 patients (18.3%), a sustained viral response (SVR) in 43 out of 45 patients (95.5%) receiving an antiviral treatment after follow-up, whereas persistence of HCV occurred in six out of 60 patients (10%). C24-ceramide (C24-Cer)-levels increased at follow-up in patients with spontaneous HCV eradication (p < 0.01), as compared to baseline. Sphingosine and sphinganine values were significantly upregulated in patients unable to clear HCV over time compared to patients with spontaneous clearance of HCV infection on follow-up (p = 0.013 and 0.006, respectively). In summary, the persistence of HCV after acute infection induces a downregulation of C24Cer and a simultaneous elevation of serum sphingosine and sphinganine concentrations.


Subject(s)
Ceramides/metabolism , Hepacivirus , Hepatitis C/metabolism , Hepatitis C/virology , Sphingosine/analogs & derivatives , Sphingosine/blood , Adult , Angiopoietin-Like Protein 3 , Angiopoietin-like Proteins , Angiopoietins/metabolism , Antiviral Agents/therapeutic use , Biomarkers , Coinfection , Female , Genotype , HIV Infections , Hepacivirus/genetics , Hepatitis C/diagnosis , Hepatitis C/drug therapy , Humans , Male , Middle Aged , Viral Load , Young Adult
6.
Med Microbiol Immunol ; 202(2): 117-24, 2013 Apr.
Article in English | MEDLINE | ID: mdl-22983722

ABSTRACT

To explore CD4-cell and viral evolution in relation to different levels of HIV-1 replication, as observed during protease inhibitor (PI)-based antiretroviral therapy. Adult HIV-1 infected cohort patients, receiving historical salvage therapy with daily doses of saquinavir (2,000 mg), ritonavir (200 mg) and either lopinavir (800 mg) or atazanavir (300 mg) for >36 weeks were retrospectively analysed for highest detectable viral load up to week 96 and assigned to groups according to the viral load level: always <50 copies/ml (1), 50-199 copies/ml (2), 200-499 copies/ml (3) and ≥500 copies/ml (4). A total of 126 patients were evaluated; at baseline, median CD4-cell count was 204/mm(3), HIV-1 RNA was 5.13 Log10-copies/ml and duration of prior HIV-1 infection was 11.7 years. Patients were assigned by 43, 30, 7 and 20 % to groups 1-4. Median observation time was 136 weeks (range: 38-304); at weeks 48/96, the CD4-cell gains for groups 1-4 were +88/+209, +209/+349, +67/+300 and +114.5/+ 128, respectively. After fitting data in a linear fixed effect model, ascending CD4 slopes were continuously increasing for group 1, similarly for 2 and clearly decreasing for 3-4 (p = 0.0006). Of 25 individuals from group 4, patient number with major IAS-USA protease mutations increased from 5 to 10 before and after failing PI therapy, whereas minor mutations remained stable (n = 18). On double-boosted PI therapy, CD4-cell increases through week 96 were similar for patients at always undetectable or with detection of low viral load. Viral detection >200 copies/ml was associated with decreasing CD4-cell slopes and emergence of major mutations, supporting this as benchmark for virological failure definition on PI therapy.


Subject(s)
Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , HIV Infections/immunology , HIV Protease Inhibitors/therapeutic use , HIV-1/physiology , Virus Replication , Adult , Aged , Anti-HIV Agents/pharmacology , CD4 Lymphocyte Count , Drug Resistance, Viral/genetics , Female , HIV Infections/virology , HIV Protease Inhibitors/pharmacology , HIV-1/drug effects , Human Immunodeficiency Virus Proteins/genetics , Humans , Male , Middle Aged , Mutation , Risk Factors , Treatment Failure , Treatment Outcome , Viral Load
7.
JHEP Rep ; 5(7): 100701, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37305441

ABSTRACT

Background & Aims: Ongoing transmission of HCV infections is associated with risk factors such as drug injection, needlestick injuries, and men who have sex with men (MSM). Ways of transmission, the course of acute infection, changes of virologic features, and incidence over time are not well known. Methods: Over a period of 10 years, n = 161 patients with recently acquired HCV infection (RAHC) (median follow-up 6.8 years) were prospectively enrolled. NS5B sequencing was performed to re-evaluate the HCV genotype (GT) and for phylogenetic analyses. Results: Patients with RAHC were mainly male (92.5%), MSM (90.1%), and HIV-coinfected (86.3%). Transmission risk factors for MSM and non-MSM were sexual risk behaviour (100 and 6.3%, respectively), injection drug use (9.7 and 37.5%, respectively), and nasal drug use (15.2 and 0%, respectively). Spontaneous and interferon- or direct-acting antiviral-based clearance rates were 13.6, 84.3 and 93.4%, respectively. Mean RAHC declined from 19.8 in the first to 13.2 in the past five study years. Although the majority of infections was caused by HCV GT1a, the frequency of HCV GT4d and slightly HCV GT3a increased over time. No relevant clustering of HCV isolates was observed in non-MSM. However, 45% of HCV GT1a and 100% of HCV GT4d MSM cases clustered with MSM isolates from other countries. Travel-associated infections were supported by personal data in an MSM subgroup. No international clustering was detected in MSM with HCV GT1b or HCV GT3a. Conclusions: RAHCs were mainly diagnosed in HIV-coinfected MSM patients and were associated with sexual risk behaviour. Spontaneous clearance rates were low, and phylogenetic clusters were observed in the majority of patients. Impact and Implications: We evaluated the occurrence and transmission of recently acquired HCV infections (RAHCs) over a period of 10 years. Our data demonstrate that the presence of RAHC was mainly found in HIV-coinfected MSM, with internationally connected transmission networks being observed in the majority of patients. Spontaneous clearance rates were low, and reinfection rates increased mainly driven by a small subset of MSM patients with high-risk behaviour.

8.
BMC Gastroenterol ; 12: 27, 2012 Mar 27.
Article in English | MEDLINE | ID: mdl-22453133

ABSTRACT

BACKGROUND: Liver fibrosis in human immunodeficiency virus (HIV)-infected individuals is mostly attributable to co-infection with hepatitis B or C. The impact of other risk factors, including prolonged exposure to combined antiretroviral therapy (cART) is poorly understood. Our aim was to determine the prevalence of liver fibrosis and associated risk factors in HIV-infected individuals based on non-invasive fibrosis assessment using transient elastography (TE) and serum biomarkers (Fibrotest [FT]). METHODS: In 202 consecutive HIV-infected individuals (159 men; mean age 47 ± 9 years; 35 with hepatitis-C-virus [HCV] co-infection), TE and FT were performed. Repeat TE examinations were conducted 1 and 2 years after study inclusion. RESULTS: Significant liver fibrosis was present in 16% and 29% of patients, respectively, when assessed by TE (≥ 7.1 kPa) and FT (> 0.48). A combination of TE and FT predicted significant fibrosis in 8% of all patients (31% in HIV/HCV co-infected and 3% in HIV mono-infected individuals). Chronic ALT, AST and γ-GT elevation was present in 29%, 20% and 51% of all cART-exposed patients and in 19%, 8% and 45.5% of HIV mono-infected individuals. Overall, factors independently associated with significant fibrosis as assessed by TE (OR, 95% CI) were co-infection with HCV (7.29, 1.95-27.34), chronic AST (6.58, 1.30-33.25) and γ-GT (5.17, 1.56-17.08) elevation and time on dideoxynucleoside therapy (1.01, 1.00-1.02). In 68 HIV mono-infected individuals who had repeat TE examinations, TE values did not differ significantly during a median follow-up time of 24 months (median intra-patient changes at last TE examination relative to baseline: -0.2 kPa, p = 0.20). CONCLUSIONS: Chronic elevation of liver enzymes was observed in up to 45.5% of HIV mono-infected patients on cART. However, only a small subset had significant fibrosis as predicted by TE and FT. There was no evidence for fibrosis progression during follow-up TE examinations.


Subject(s)
Elasticity Imaging Techniques , HIV Infections/complications , Hepatitis C/complications , Liver Cirrhosis/blood , Liver Cirrhosis/pathology , Adult , Alanine Transaminase/blood , Anti-Retroviral Agents/adverse effects , Apolipoprotein A-I/blood , Aspartate Aminotransferases/blood , Bilirubin/blood , Biomarkers/blood , Coinfection/complications , Confidence Intervals , Female , Haptoglobins/metabolism , Humans , Liver Cirrhosis/etiology , Longitudinal Studies , Male , Middle Aged , Odds Ratio , Risk Factors , alpha-Macroglobulins/metabolism , gamma-Glutamyltransferase/blood
9.
Antimicrob Agents Chemother ; 55(11): 5362-6, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21825300

ABSTRACT

Genotypes of samples from protease inhibitor-naïve patients in Frankfurt's HIV Cohort were analyzed with five tipranavir resistance prediction algorithms. Mean scores were higher in non-B than in B subtypes. The proportion of non-B subtypes increased with increasing scores, except in weighted algorithms. Virtual and in vitro phenotype analyses of samples with increased scores showed no reduced tipranavir susceptibility. Current algorithms appear suboptimal for interpretation of resistance to tipranavir in non-B subtypes; increased scores might reflect algorithm bias rather than "natural resistance."


Subject(s)
Anti-HIV Agents/therapeutic use , Drug Resistance, Viral/genetics , HIV Infections/drug therapy , HIV Protease Inhibitors/therapeutic use , Pyridines/therapeutic use , Pyrones/therapeutic use , Genotype , Humans , Mutation , Sulfonamides
10.
Liver Int ; 30(8): 1169-72, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20633101

ABSTRACT

BACKGROUND: An ongoing HCV epidemic currently affects a growing proportion of HIV-positive men who have sex with men (MSM) in Europe. Recently in the North-Rhine region of Germany, we have observed an increase in acute HCV infections of genotype 4 (HCV-4). AIMS: To characterize the current spread of HCV-4 among German MSM using a molecular epidemiological approach. METHODS: Patient characteristics and sera were collected for HIV-positive MSM diagnosed with acute HCV-4 infections in the North-Rhine region (n=14), Hamburg (n=14), Frankfurt (n=4) and Berlin (n=4). Part of the HCV NS5B region (436 bp) was amplified, sequenced and compared with HCV-4 sequences from HIV-positive Dutch, English and French MSM (n=50) as well as unrelated HCV risk groups (n=61). RESULTS: NS5B sequences were obtained from 35/36 (97%) of German cases, all of which were HCV subtype 4d (HCV-4d). The phylogenetic analysis of HCV sequences revealed two MSM-specific HCV-4d clusters of 71 and 12 sequences. All except one of the German MSM belonged to a large MSM-specific HCV cluster containing MSM from all four different European countries. None of the HCV-4 strains circulating among injecting drug users or in HCV-4 endemic areas were part of the MSM-specific clusters. CONCLUSIONS: HCV rapidly spreads among European HIV-positive MSM through a joint international transmission network, separate from that of injecting drug users. In order to contain this epidemic, non-parenteral routes of transmission, such as unsafe sex, must be taken into consideration and prevention measures should be refocused accordingly.


Subject(s)
HIV Infections/complications , Hepacivirus/genetics , Hepatitis C/complications , Hepatitis C/epidemiology , Hepatitis C/virology , Homosexuality, Male , Phylogeny , Adult , Base Sequence , Computational Biology , Germany/epidemiology , Humans , Likelihood Functions , Male , Middle Aged , Models, Genetic , Molecular Sequence Data , Sequence Analysis, DNA , Viral Nonstructural Proteins/genetics
11.
Antivir Ther ; 12(1): 25-30, 2007.
Article in English | MEDLINE | ID: mdl-17503744

ABSTRACT

OBJECTIVE: Long-term evaluation of viral evolution in patients who continued first-line therapy with zidovudine/lamivudine/abacavir (Trizivir [TZV]) in the presence of low-level viral replication and assessment of the impact of mutational patterns selected under TZV on viral load (VL), CD4+ T-cell count (CD4) and subsequent therapeutic options. DESIGN: Analysis of viral evolution based on genotypic resistance tests (GRT) from samples collected during non-suppressive first-line therapy with TZV. METHODS: Patients from the Frankfurt HIV cohort with at least 3 months uninterrupted first-line therapy with TZV in whom VL and CD4 measurements were performed at baseline and at follow up were identified. Criteria for virological failure (VF) were two consecutive VL >400 copies/ml. GRTs were required at baseline, VF and last visit (LV). RESULTS: Initially, 23/119 patients were classified as VF; 4/23 were lost to follow up. Median time to VF was 48 weeks. Because of the observed virological and immunological benefit, patients continued TZV for a median of 87 weeks despite detectable viraemia. Median CD4 increase and VL reduction at LV were 120 cells/mm3 and 317,100 copies/ml, respectively, compared to baseline. After 54 weeks of treatment with detectable VL, three mutational patterns were observed: Group A (n=4) characterized by M184V without further regimen-associated mutations, group B (n=9) by M184V accompanied by one to three thymidine analogue mutations (TAMs), and group C (n=6) by M184V and four to six TAMs. No virological or CD4 parameters correlated with these patterns. Group A remained unchanged, thus preserving activity of most nucleoside analogues (NA). However, in the majority of patients (groups B and C) accumulation of mutations at different rates was observed, leading to a sequential loss of NA options. CONCLUSIONS: Continuous treatment with TZV in the presence of viral replication is associated with a stepwise accumulation of resistance mutations. M184V was present in all cases, not followed by further selection of TAMs in a small, unpredictable subgroup of patients. However, in the majority of patients selection of M184V was associated with accumulation of TAMs at different rates leading to a substantial loss of active NAs, despite continuous virological and immunological benefit when compared with baseline.


Subject(s)
Anti-HIV Agents/therapeutic use , DNA, Viral/blood , Dideoxynucleosides/therapeutic use , Drug Resistance, Viral/genetics , HIV Infections/drug therapy , HIV-1/genetics , Lamivudine/therapeutic use , Mutation , Reverse Transcriptase Inhibitors/therapeutic use , Zidovudine/therapeutic use , Anti-HIV Agents/pharmacology , Antiretroviral Therapy, Highly Active , CD4 Lymphocyte Count , Cohort Studies , Dideoxynucleosides/pharmacology , Drug Combinations , Drug Monitoring , Follow-Up Studies , Genotype , Germany , HIV Infections/blood , HIV Infections/genetics , HIV Infections/immunology , HIV Infections/virology , HIV-1/drug effects , HIV-1/physiology , Humans , Lamivudine/pharmacology , Methionine , Reverse Transcriptase Inhibitors/pharmacology , Thymidine , Time Factors , Treatment Failure , Valine , Viral Load , Virus Replication/drug effects , Zidovudine/pharmacology
12.
Virology ; 485: 213-22, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26295281

ABSTRACT

Little is known about the importance of the hepatitis C virus (HCV) NS3 protease in acute hepatitis C. In this prospective study, 82 consecutive patients with acute hepatitis C and human immunodeficiency virus (HIV) coinfection were enrolled. Individuals were infected with highly related HCV strains and the baseline NS3 quasispecies diversity and complexity was higher compared to a chronic hepatitis C control group (P<0.0001). Both parameters were comparable in patients with spontaneous clearance (n=6) versus treatment-induced SVR (n=5) or development of chronic hepatitis C (n=9). Longitudinal NS3 quasispecies kinetics showed a trend to a decreasing diversity and complexity (P<0.05) within 4 weeks in patients with spontaneous clearance compared to the other groups. The innate immune signalling protein CARDIF was cleaved to a similar extent independent of the outcome. Together with a more pronounced viral load decline (P<0.05), an early decreasing NS3 quasispecies evolution indicates spontaneous clearance of acute hepatitis C.


Subject(s)
Coinfection , Evolution, Molecular , HIV Infections/virology , Hepacivirus/genetics , Hepatitis C/virology , Viral Nonstructural Proteins/genetics , Acute Disease , Adaptor Proteins, Signal Transducing/metabolism , Adult , Female , Genotype , HIV Infections/diagnosis , Hepatitis C/diagnosis , Humans , Male , Middle Aged , Patient Outcome Assessment , Phylogeny , Prospective Studies , Proteolysis , Reassortant Viruses/genetics , Viral Nonstructural Proteins/classification , Viral Nonstructural Proteins/metabolism
13.
J Virol Methods ; 190(1-2): 34-40, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23454647

ABSTRACT

Detection of minor variant viral quasispecies of the rtV173L+rtL180M+rtM204V combination mutation in the hepatitis B virus (HBV) polymerase mediating both lamivudine resistance and vaccine escape is potentially important for tracking the development and evolution of resistance within both individuals and populations. A highly sensitive and specific assay to quantitate HBV genomes was developed with this mutation combination directly from viral DNA in serum using allele-specific quantitative PCR with locked nucleic acid primers and a minor groove binder probe. This combination of primers and probe yields a linear detection range down to 150 copies. This strategy has 100% specificity even in mixtures of predominately wild type genomes. The assay accurately detected 3×10² copies of the triple mutant spiked into 3 × 108 copies of the wild-type genomes (0.0001%), while maintaining 100% specificity. This approach was validated using serum from a subject infected with known lamivudine-resistant HBV. The triple mutant viral population was quantitated at 2.86 × 108 copies/ml within a total viral concentration of 1.03 × 10¹° copies/ml of serum (2.8%). This quantitative allele-specific PCR strategy therefore is a useful method for highly sensitive and specific detection of point mutation combinations that are clinically important in the pathogenesis of drug resistance and/or immune escape.


Subject(s)
Alleles , DNA, Viral/genetics , Drug Resistance, Viral , Hepatitis B virus/drug effects , Hepatitis B virus/genetics , Hepatitis B, Chronic/virology , Mutation , Antiviral Agents/pharmacology , DNA Primers , Hepatitis B virus/immunology , Hepatitis B virus/isolation & purification , Hepatitis B, Chronic/drug therapy , Humans , Immune Evasion , Lamivudine/pharmacology , Microbial Sensitivity Tests/methods , Molecular Diagnostic Techniques/methods , Oligonucleotide Probes , Sensitivity and Specificity
14.
Br J Clin Pharmacol ; 62(5): 552-9, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17061962

ABSTRACT

AIMS: To evaluate the pharmacokinetics of nevirapine and any possible influencing factors in pregnant women (n = 16), nonpregnant women (n = 13) and men (n = 14), who received nevirapine 200 mg twice daily together with nucleoside reverse transcriptase inhibitors. METHODS: Blood samples were taken for 12 h at steady state. Nevirapine concentrations were measured by liquid chromatography-tandem mass spectrometry. The influence of gender, age, body weight and comedication on minimum and maximum concentrations (C(min), C(max)), area under the concentration-time curve (AUC), total clearance (CL(tot)), half-life (t(1/2)) and volume of distribution (V(d)) was analysed by multivariate techniques. RESULTS: Mean [95% confidence interval (CI)]C(max), AUC(ss) and clearance were 5221 ng ml(-1) (4267, 6175), 50 789 ng (-1)h ml(-1) (43 453, 58 125) and 69.9 ml min(-1) for men, 5871 ng ml(-1) (4848, 6895), 57 045 ng h(-1) ml(-1) (45 997, 68 093) and 65.6 ml min(-1) for nonpregnant women and 4505 ng ml(-1) (3644, 5366), 44 579 ng h(-1) ml(-1) (36 564, 52 594) and 82.1 ml min(-1) for pregnant women. The differences between pregnant and nonpregnant women (% difference, 95% CI) in C(max) (-30.3; -28.5, -33.0), AUC(ss) (-28.0; - 25.8, - 29.5) and clearance (20.2; 26.6, 15.6) reached statistical significance (P = 0.010, P = 0.028 and P = 0.028, respectively). The multivariate analysis underscored the influence of bodyweight on the plasma exposure to nevirapine. CONCLUSIONS: Pregnant women exhibited an increased nevirapine clearance and comparably low plasma concentrations, whereas women with a low bodyweight achieved high plasma nevirapine concentrations. The large variability in nevirapine concentrations in women may lead to loss of efficacy and viral resistance, or drug toxicity, and therefore these patients should be monitored frequently.


Subject(s)
Anti-HIV Agents/pharmacokinetics , HIV Infections/drug therapy , Nevirapine/pharmacokinetics , Pregnancy Complications, Infectious/drug therapy , Reverse Transcriptase Inhibitors/pharmacokinetics , Adult , Anti-HIV Agents/therapeutic use , Female , Humans , Male , Middle Aged , Nevirapine/therapeutic use , Pregnancy , Pregnancy Trimester, Third , Reverse Transcriptase Inhibitors/therapeutic use
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