Browsing by Author "Frenkel L"

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    Association of Maternal Viral Load and CD4 Count With Perinatal HIV-1 Transmission Risk During Breastfeeding in the PROMISE Postpartum Component.
    (2021-Oct-01) Flynn PM; Taha TE; Cababasay M; Butler K; Fowler MG; Mofenson LM; Owor M; Fiscus S; Stranix-Chibanda L; Coutsoudis A; Gnanashanmugam D; Chakhtoura N; McCarthy K; Frenkel L; Beck I; Mukuzunga C; Makanani B; Moodley D; Nematadzira T; Kusakara B; Patil S; Vhembo T; Bobat R; Mmbaga BT; Masenya M; Nyati M; Theron G; Mulenga H; Shapiro DE; University of North Carolina Project-Malawi, Kamuzu Central Hospital, Lilongwe, Malawi.; Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA.; Wits Reproductive Health and HIV Institute, Johannesburg, South Africa.; Division of AIDS, National Institute of Allergy and Immunology, National Institutes of Health, Bethesda, MD.; Elizabeth Glaser Pediatric AIDS Foundation, Washington, DC.; Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD.; Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, NC.; Maternal and Pediatric Infectious Disease Branch, Division of Extramural Research, Eunice Kennedy Shriver Institute of Child Health and Human Development, National Institutes of Health, Rockville, MD.; Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN.; Department of Pediatrics and Child Health, Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa.; Makerere University-Johns Hopkins University Research Collaboration, Kampala, Uganda.; Department of Obstetrics and Gynaecology, Centre for the AIDS Programme of Research in South Africa and School of Clinical Medicine, College of Health Sciences, University of KwaZulu Natal, Durban, South Africa.; University of Zimbabwe Clinical Trials Research Centre, Harare, Zimbabwe.; Department of Obstetrics and Gynecology, College of Medicine, University of Malawi, Blantyre, Malawi.; Perinatal HIV Research Unit, Chris Baragwanath Hospital, Johannesburg, South Africa.; Department of Paediatrics and Child Health, Faculty of Medicine and Health Sciences, University of Zimbabwe, Harare, Zimbabwe.; Department of Obstetrics and Gynecology, Byramjee Jeejeebhoy Government Medical College and Johns Hopkins Clinical Trials Unit, Pune, India.; Department of Pediatrics and Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA.; Department of Pediatrics, Kilimanjaro Christian Medical Centre and Kilimanjaro Christian Medical University College, Moshi, Tanzania.; Center for Biostatistics in AIDS Research, Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, MA.; Department of Pediatrics and Child Health, University of KwaZulu-Natal, Durban, South Africa.; Department of Obstetrics and Gynecology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa; and.; Centre for Infectious Disease Research in Zambia, Lusaka, Zambia.; Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD.; FHI 360, Durham, NC.; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)
    BACKGROUND: Breastfeeding mothers with HIV infection not qualifying for antiretroviral therapy (ART) based on country-specific guidelines at the time of the Promoting Maternal-Infant Survival Everywhere trial and their uninfected neonates were randomized to maternal ART (mART) or infant nevirapine prophylaxis (iNVP) postpartum. HIV transmission proportions were similar (<1%) in the 2 arms. We assessed whether maternal viral load (MVL) and CD4 cell counts were associated with breastfeeding HIV transmission. METHODS: MVL was collected at entry (7-14 days postpartum) and at weeks 6, 14, 26, and 50 postpartum. CD4 cell counts were collected at entry and weeks 14, 26, 38, and 50 postpartum. Infant HIV-1 nucleic acid test was performed at weeks 1 and 6, every 4 weeks until week 26, and then every 12 weeks. The associations of baseline and time-varying MVL and CD4 cell counts with transmission risk were assessed using time-to-event analyses by randomized treatment arm. RESULTS: Two thousand four hundred thirty-one mother-infant pairs were enrolled in the study. Baseline MVL (P = 0.11) and CD4 cell counts (P = 0.51) were not significantly associated with infant HIV-1 infection. Time-varying MVL was significantly associated with infant HIV-1 infection {hazard ratio [95% confidence interval (CI)]: 13.96 (3.12 to 62.45)} in the mART arm but not in the iNVP arm [hazard ratio (95% CI): 1.04 (0.20 to 5.39)]. Time-varying CD4 cell counts were also significantly associated with infant HIV-1 infection [hazard ratio (95% CI): 0.18 (0.03 to 0.93)] in the mART arm but not in the iNVP arm [hazard ratio (95% CI): 0.38 (0.08 to 1.77)]. CONCLUSIONS: In women receiving mART, increased MVL and decreased CD4 cell counts during breastfeeding were associated with increased risk of infant HIV-1 infection.
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    Impact of CYP2B6 genotype, tuberculosis therapy, and formulation on efavirenz pharmacokinetics in infants and children under 40 months of age.
    (2022-Mar-15) Nikanjam M; Tran L; Chadwick EG; Bwakura-Dangarembizi M; Bolton Moore C; Samson P; Spector SA; Chakhtoura N; Jean-Philippe P; Frenkel L; Zimmer B; Benns A; Libous J; Capparelli EV; Maternal and Pediatric Infectious Disease Branch (MPIDB), Eunice Kennedy Shriver National Institute for Child Health and Human Development, National Institutes of Health.; Department of Paediatrics and Child Health, University of Zimbabwe College of Health Sciences, Harare, Zimbabwe.; Frontier Science and Technology Research Foundation, Amherst, New York.; Division of Pharmacotherapy and Experimental Therapeutics, School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina.; Department of Pediatrics, School of Medicine, University of California San Diego, La Jolla, California.; Department of Pediatrics, University of Washington, Seattle, Washington.; Department of Pediatrics, Northwestern University's Feinberg School of Medicine, Chicago, Illinois, USA.; Statistical and Data Management Center (SDMC) Harvard T.H. Chan School of Public Health, Center for Biostatistics in AIDS Research/Frontier Science Foundation, Boston, Massachusetts.; Division of AIDS, National Institutes of Allergy and Infectious Diseases, Bethesda, Maryland, USA.; Centre for Infectious Disease Research in Zambia, Lusaka, Zambia.; Centre for Infectious Diseases, University of Alabama at Birmingham, Birmingham, Alabama.; IMPAACT Operations Center, FHI360, Durham, North Carolina, USA.; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)
    OBJECTIVE: Dosing efavirenz (EFV) in children less than 3 years of age is challenging due to large variability in drug levels. This study evaluated differences in pharmacokinetics with tuberculosis (TB) therapy, formulation, age, and CYP2B6 genotype. DESIGN: Pharmacokinetic data from three IMPAACT/PACTG studies (P382, P1021, and P1070) for children initiating therapy less than 40 months of age were evaluated. METHODS: Pharmacokinetic data were combined in a population pharmacokinetic model. Exposure from the 2-week pharmacokinetic visit was compared with changes in viral RNA between the Week 0 and Week 4 visits. RESULTS: The model included 103 participants (19 on TB therapy). CYP2B6 516 genotype information was available for 82 participants (TT: 15, GT: 28, GG: 39). Median age at the first pharmacokinetic visit was 17.0 months (range: 2.0-39.0 months). Liquid formulation led to a 42% decrease in bioavailability compared with opened capsules. TB therapy (isoniazid and rifampin) led to a 29% decreased clearance, however Monte Carlo simulations demonstrated the majority of participants on TB therapy receiving standard EFV dosing to be in the target area under the curve range. Clearance was 5.3-fold higher for GG than TT genotype and 3.3-fold higher for GT than TT genotype. Age did not have a significant effect on clearance in the final model. Initial viral RNA decay was lower for patients in the lowest quartile of exposures (area under the curves) than for higher quartiles (P = 0.013). CONCLUSION: EFV dosing should account for CYP2B6 516 genotype and formulation, but does not require adjustment for concurrent TB therapy.