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Makita-Chingombe F, Ocque AJ, DiFrancesco R, Maponga C, Muzambi F, Monera-Penduka TG, Mudzviti T, Mtisi TJ, Morse GD. Development and validation of a high performance liquid chromatography method to determine nevirapine in plasma in a resource-limited setting. Afr J Lab Med 2019; 8:880. [PMID: 31205870 PMCID: PMC6556864 DOI: 10.4102/ajlm.v8i1.880] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 11/02/2018] [Indexed: 12/14/2022] Open
Abstract
Background There are several instances where nevirapine pharmacokinetic monitoring may be useful, such as in special populations or pharmacokinetic drug interaction studies that require the ascertainment of nevirapine pharmacokinetics in the sub-Saharan region. Objectives The main aim of this study was to produce a validated, sustainable and relevant nevirapine assay method that meets bio-analytical regulatory requirements. Methods The developed method utilised a Waters 2795 Alliance high performance liquid chromatography system with a 2996 photo diode array detector, an Atlantis dC18 5 micron, 3.9 mm × 150 mm analytical column and a gradient flow rate of 1 mL/min. Ultraviolet detection data were collected from 210 nm to 400 nm, extracted at 260 nm, and processed for nevirapine and internal standard peak height responses. Results The method proved to be linear (R2 0.995), precise (+1.92% – +9.69%) and accurate (-9.70% – 12.0%). Recovery for the analyte and internal standard was between 98.8% and 114%. The method showed good specificity as no interferences were caused by common African traditional medicines, anti-tuberculosis medications or other concomitant antiretrovirals nor endogenous components. Conclusion The method is reproducible, relevant to our setting and uses considerably low plasma volumes with preservation of some consumables, a desirable key factor in a resource-limited setting.
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Affiliation(s)
- Faithful Makita-Chingombe
- International Pharmacology Specialty Laboratory, School of Pharmacy, University of Zimbabwe College of Health Science, Harare, Zimbabwe
| | - Andrew J Ocque
- Center for Integrated Global Biomedical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Translational Pharmacology Research Core, New York State Center of Excellence in Bioinformatics and Life Sciences, The State University of New York, Buffalo, New York, United States
| | - Robin DiFrancesco
- Center for Integrated Global Biomedical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Translational Pharmacology Research Core, New York State Center of Excellence in Bioinformatics and Life Sciences, The State University of New York, Buffalo, New York, United States
| | - Charles Maponga
- International Pharmacology Specialty Laboratory, School of Pharmacy, University of Zimbabwe College of Health Science, Harare, Zimbabwe.,Center for Integrated Global Biomedical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Translational Pharmacology Research Core, New York State Center of Excellence in Bioinformatics and Life Sciences, The State University of New York, Buffalo, New York, United States
| | - Farai Muzambi
- International Pharmacology Specialty Laboratory, School of Pharmacy, University of Zimbabwe College of Health Science, Harare, Zimbabwe
| | - Tsitsi G Monera-Penduka
- International Pharmacology Specialty Laboratory, School of Pharmacy, University of Zimbabwe College of Health Science, Harare, Zimbabwe
| | - Tinashe Mudzviti
- International Pharmacology Specialty Laboratory, School of Pharmacy, University of Zimbabwe College of Health Science, Harare, Zimbabwe
| | - Takudzwa J Mtisi
- International Pharmacology Specialty Laboratory, School of Pharmacy, University of Zimbabwe College of Health Science, Harare, Zimbabwe
| | - Gene D Morse
- Center for Integrated Global Biomedical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Translational Pharmacology Research Core, New York State Center of Excellence in Bioinformatics and Life Sciences, The State University of New York, Buffalo, New York, United States
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Gopalan BP, Mehta K, D'souza RR, Rajnala N, A. K. HK, Ramachandran G, Shet A. Sub-therapeutic nevirapine concentration during antiretroviral treatment initiation among children living with HIV: Implications for therapeutic drug monitoring. PLoS One 2017; 12:e0183080. [PMID: 28827836 PMCID: PMC5565187 DOI: 10.1371/journal.pone.0183080] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 07/29/2017] [Indexed: 12/04/2022] Open
Abstract
Nevirapine, a component of antiretroviral therapy (ART) in resource-limited settings, known for auto-induction of metabolism, is initiated at half therapeutic dose until day 14 (‘lead-in period’), and subsequently escalated to full dose. However, studies have shown that this dosing strategy based on adult studies may not be appropriate in children, given that younger children have higher drug clearance rates. In this prospective cohort study, we studied trough plasma nevirapine levels by high performance liquid chromatography (HPLC) at days 7, 14 (lead-in period) and 28 (full dose period) after ART initiation amongst HIV-1 infected children initiating nevirapine-based ART in southern India. Among the 20 children (50% male, median age 9 years) included in the study, sub-therapeutic trough plasma nevirapine concentration (<4μg/ml) was seen in 65% (13/20) of children during the lead-in period within two weeks of ART initiation and among 10% of children at 4 weeks during full-dose nevirapine. Adherence was documented as ≥95% in all children by both caregiver self-report and pill count. Median nevirapine concentrations achieved at week 1 was 4.8 μg/ml, significantly lower than 8 μg/ml, the concentration achieved at week 4 (p = 0.034). Virological failure at one year of ART was observed in six children, and was not associated with median nevirapine concentration achieved during week 1, 2 or 4. We conclude that the dose escalation strategy currently practiced among young children living with HIV-1 resulted in significant subtherapeutic nevirapine concentration (≤4μg/ml) during the lead-in period. We call for a closer look at pediatric-focused dosing strategies for nevirapine initiation in young children. Further studies to establish age-appropriate threshold nevirapine concentration are warranted in young children to corroborate the role of therapeutic drug monitoring in predicting virological outcome.
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Affiliation(s)
- Bindu Parachalil Gopalan
- Division of Infectious Diseases, St. John’s Research Institute, St. John’s National Academy of Health Sciences, Bangalore, Karnataka, India
- The Institute Of Trans-Disciplinary Health Sciences and Technology (TDU), Bangalore, Karnataka, India
| | - Kayur Mehta
- Department of Pediatrics, St. John's Medical College Hospital, Bangalore, Karnataka, India
| | - Reena R. D'souza
- Division of Infectious Diseases, St. John’s Research Institute, St. John’s National Academy of Health Sciences, Bangalore, Karnataka, India
| | - Niharika Rajnala
- Division of Infectious Diseases, St. John’s Research Institute, St. John’s National Academy of Health Sciences, Bangalore, Karnataka, India
| | - Hemanth Kumar A. K.
- National Institute for Research in Tuberculosis (Indian Council of Medical Research), Chennai, Tamil Nadu, India
| | - Geetha Ramachandran
- National Institute for Research in Tuberculosis (Indian Council of Medical Research), Chennai, Tamil Nadu, India
| | - Anita Shet
- Division of Infectious Diseases, St. John’s Research Institute, St. John’s National Academy of Health Sciences, Bangalore, Karnataka, India
- * E-mail:
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Bienczak A, Cook A, Wiesner L, Mulenga V, Kityo C, Kekitiinwa A, Walker AS, Owen A, Gibb DM, Burger D, McIlleron H, Denti P. Effect of diurnal variation, CYP2B6 genotype and age on the pharmacokinetics of nevirapine in African children. J Antimicrob Chemother 2017; 72:190-199. [PMID: 27707991 PMCID: PMC5161049 DOI: 10.1093/jac/dkw388] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 08/16/2016] [Accepted: 08/17/2016] [Indexed: 12/21/2022] Open
Abstract
OBJECTIVES To characterize the effects of CYP2B6 polymorphisms, diurnal variation and demographic factors on nevirapine pharmacokinetics in African children. METHODS Non-linear mixed-effects modelling conducted in NONMEM 7.3 described nevirapine plasma concentration-time data from 414 children aged 0.3-15 years. RESULTS Nevirapine pharmacokinetics was best described using a one-compartment disposition model with elimination through a well-stirred liver model accounting for a first-pass effect and transit-compartment absorption. Intrinsic clearance was affected by diurnal variation (characterized using a cosine function with peak amplitude 29% at 12 noon) and CYP2B6 metabolizer status [extensive metabolizer (EM) 516GG|983TT, reference; intermediate metabolizer (IM) 516GT|983TT or 516GG|983TC, 17% lower; slow metabolizer (SM) 516TT|983TT or 516GT|983TC, 50% lower; ultra-slow metabolizer (USM) 516GG|983CC, 68% lower]. Age was found to affect pre-hepatic bioavailability: 31.7% lower at birth and increasing exponentially. Median (90% CI) evening Cmin values in the different metabolizer groups were 5.01 (3.01-7.47), 6.55 (3.65-13.32), 11.59 (5.44-22.71) and 12.32 (12.32-27.25) mg/L, respectively. Evening Cmin values were <3 mg/L in 43% of EM weighing <6 kg and 26% of IM weighing <6 kg, while 73% of SM and 88% of USM in all weight-bands had evening Cmin values >8 mg/L. Cmin was not markedly affected by administration time, but was altered by unequal splitting of the daily dose. CONCLUSIONS Diurnal variation does not greatly affect nevirapine exposure. However, when daily doses cannot be split equally, the larger dose should be given in the morning. To achieve homogeneous exposures, nevirapine doses for SM and USM should be reduced by 50%, and children weighing <6 kg with EM or IM metabolizer status should receive the same dose as children weighing 6-10 kg.
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Affiliation(s)
- Andrzej Bienczak
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Adrian Cook
- MRC Clinical Trials Unit at University College London, London, UK
| | - Lubbe Wiesner
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Veronica Mulenga
- Department of Paediatrics and Child Health, University Teaching Hospital, Lusaka, Zambia
| | - Cissy Kityo
- Joint Clinical Research Centre, Kampala, Uganda
| | - Addy Kekitiinwa
- Baylor College of Medicine Bristol-Myers Squibb Children's Clinical Centre of Excellence, Kampala, Uganda/Gulu Regional Centre of Excellence, Gulu, Uganda
| | - A Sarah Walker
- MRC Clinical Trials Unit at University College London, London, UK
| | - Andrew Owen
- Department of Molecular and Clinical Pharmacology, University of Liverpool, Liverpool, UK
| | - Diana M Gibb
- MRC Clinical Trials Unit at University College London, London, UK
| | - David Burger
- Department of Pharmacy, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Helen McIlleron
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Paolo Denti
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
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Mukherjee A, Singla M, Velpandian T, Sirohiwal A, Vajpayee M, Singh R, Kabra SK, Lodha R. Pharmacokinetics of nevirapine, stavudine and lamivudine in Indian HIV-infected children receiving generic fixed dose combinations. Indian Pediatr 2015; 51:191-7. [PMID: 24736906 DOI: 10.1007/s13312-014-0382-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To determine the trough and two hour plasma levels of nevirapine, stavudine, and lamivudine when administered in fixed dose combinations (FDC). DESIGN Cross sectional. SETTING Tertiary care hospital in Northern India. PARTICIPANTS 79 HIV-infected children receiving antiretroviral therapy with FDCs for more than month. INTERVENTION Two-point sampling (0 and 2 hours after the morning dose). OUTCOME MEASURES Plasma concentrations of all three drugs were simultaneously assayed by liquid chromatography/mass spectroscopy. RESULTS Majority (77%) of children were receiving fixed dose combination of stavudine, lamivudine, nevirapine in the ratio of 6:30:50 mg. The median (IQR) trough and 2-hour plasma levels (µg/mL) of nevirapine, stavudine and lamivudine were 5.2 (4.0, 6.3) and 7.9 (6.0, 9.7); 0.1 (0.06, 0.16) and 1.1 (0.59, 1.6); 0.1 (0.02, 0.2) and 2.5 (1.4, 3.1), respectively. Very few children had sub-therapeutic plasma drug levels of stavudine (2.5%), lamivudine (7.6%) and nevirapine (10%). Inadequate viral suppression at 6 months follow up was significantly associated with initial high viral load, low CD4 percentage at the time of enrolment in study, and lower doses of lamivudine and stavudine. CONCLUSIONS The currently available generic pediatric fixed dose antiretroviral combinations in India provide adequate drug exposure in majority of children.
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Affiliation(s)
- Aparna Mukherjee
- Departments of Pediatrics, *Ocular Pharmacology and #Microbiology, All India Institute of Medical Sciences, New Delhi, India. Correspondence to: Dr Rakesh Lodha, Additional Professor, Department of Pediatrics, AIIMS, New Delhi, India.
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Impact of adherence and anthropometric characteristics on nevirapine pharmacokinetics and exposure among HIV-infected Kenyan children. J Acquir Immune Defic Syndr 2014; 67:277-86. [PMID: 25140906 DOI: 10.1097/qai.0000000000000300] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
BACKGROUND There are insufficient data on pediatric antiretroviral therapy (ART) pharmacokinetics (PK), particularly for children in low- and middle-income countries. METHODS We conducted a prospective nevirapine (NVP) PK study among HIV-infected Kenyan children aged 3-13 years initiating an NVP-based ART regimen. NVP dose timing was measured through medication event monitors. Participants underwent 2 inpatient assessments: 1 at 4-8 weeks after ART initiation and 1 at 3-4 months after ART initiation. Allometric scaling of oral clearance (CL)/bioavailability (F) and volume of distribution (Vd)/F values were computed. Nonlinear mixed-effects modeling using the first-order conditional estimation with interaction method was performed with covariates. The impact of adherence on time below minimum effective concentration was assessed in the final PK model using medication event monitors data and model-estimated individual parameters. RESULTS Among 21 children enrolled, mean age was 5.4 years and 57% were female. CL/F was 1.67 L/h and Vd/F was 3.8 L for a median child weighing 15 kg. Participants' age had a significant impact on CL/F (P < 0.05), with an estimated decrease in CL of 6.2% for each 1-year increase in age. Total body water percentage was significantly associated with Vd/F (P < 0.001). No children had >10% of time below minimum effective concentration when the PK model assumed perfect adherence compared with 10 children when adherence data were used. CONCLUSIONS Age and body composition were significantly associated with children's NVP PK parameters. ART adherence significantly impacted drug exposure over time, revealing subtherapeutic windows that may lead to viral resistance.
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Foissac F, Bouazza N, Frange P, Blanche S, Faye A, Lachassinne E, Dollfus C, Hirt D, Benaboud S, Treluyer JM, Urien S. Evaluation of nevirapine dosing recommendations in HIV-infected children. Br J Clin Pharmacol 2014; 76:137-44. [PMID: 23278548 DOI: 10.1111/bcp.12069] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Accepted: 12/16/2012] [Indexed: 11/28/2022] Open
Abstract
AIMS Nevirapine (NVP) is a non-nucleoside reverse transcriptase inhibitor used for chronic human immunodeficiency virus infections in adults and children. The aims of this study were to investigate the population pharmacokinetics of NVP in children, establish factors that influence NVP pharmacokinetics and evaluate the current dosing recommendations. METHODS Concentrations were measured on a routine basis in 94 children aged from 2 months to 17 years. A total of 390 NVP plasma concentrations were retrospectively collected, and a population pharmacokinetic model was developed with Monolix 4.0. RESULTS Nevirapine pharmacokinetics was best described by a one-compartment model with first-order absorption and elimination. After standardization to a 70 kg adult using allometry, postmenstrual age had a significant effect on the bioavailability. Estimates of apparent clearance and volume of distribution were 3.9 l h(-1) (70 kg)(-1) and 140 l (70 kg)(-1) , respectively. Based on simulations of European Medicines Agency (EMA) and World Health Organization (WHO) dosing recommendations, the probability of observing minimal concentrations below the efficacy target of 3 mg l(-1) is higher following the EMA recommendations than the WHO recommendations. However, NVP underdosing persists for the 3-6 and 6-10 kg weight ranges following the WHO recommendations. CONCLUSIONS It is suggested to increase doses to 75 and 100 mg twice daily for the 3-6 and 6-10 kg weight ranges, respectively, in order to obtain more than 95% of children with concentrations above 3 mg l(-1) .
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Affiliation(s)
- Frantz Foissac
- EA 3620-Université Paris Descartes Sorbonne Paris Cité, Unité de RechercheClinique, Hôpital Tarnier, 89 rue d’Assas, Paris, France.
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Fillekes Q, Mulenga V, Kabamba D, Kankasa C, Thomason MJ, Cook A, Ferrier A, Chintu C, Walker AS, Gibb DM, Burger DM. Pharmacokinetics of nevirapine in HIV-infected infants weighing 3 kg to less than 6 kg taking paediatric fixed dose combination tablets. AIDS 2012; 26:1795-800. [PMID: 22739394 DOI: 10.1097/qad.0b013e32835705fd] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
OBJECTIVES To evaluate pharmacokinetics of nevirapine, lamivudine and stavudine in HIV-infected Zambian infants receiving fixed dose combination (FDC) antiretroviral tablets (Triomune Baby). DESIGN Phase I/II study. METHODS Sixteen HIV-infected children at least 1 month, weighing 3 kg to less than 6 kg were enrolled. Blood was sampled at t = 0, 2, 6 and 12 h after observed intake of one FDC tablet (50 mg nevirapine, 6 mg stavudine, 30 mg lamivudine) 4 weeks after starting treatment. Safety and viral load response over 48 weeks were determined. RESULTS The median [interquartile range (IQR)] age, body weight and daily nevirapine dose in 15 included children (eight girls) were 4.8 (4.2, 8.4) months, 5.3 (4.3, 5.5) kg and 348 (326 385) mg/m, respectively. The median (IQR) nevirapine area under the concentration-time curve (AUC0-12 h), Cmax and C12 h were 70 (56, 104) h mg/l, 7.5 (6.2, 10) mg/l, and 4.3 (2.9, 6.9) mg/l, respectively. Values were on average higher than reported in adults, but approximately 20% lower than previously reported in children weighing at least 6 kg. Four of 15 (27%) children had a subtherapeutic nevirapine C12 h (defined as <3.0 mg/l) compared to only three of 63 (5%) children weighing at least 6 kg (P = 0.02), whereas children aged less than 5 months [three of six (50%)] may have the highest risk for subtherapeutic nevirapine C12 h (P = 0.24). No association was found between viral load values and nevirapine plasma pharmacokinetic parameters (P > 0.3). Stavudine-lamivudine pharmacokinetic parameters were broadly comparable to heavier children. CONCLUSION Exposure to nevirapine in African, HIV-infected infants with low body weight taking FDC tablets appears on average to be adequate, but due to large intersubject variability a relatively high proportion had subtherapeutic nevirapine C12 h levels, particularly those aged less than 5 months.
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Affiliation(s)
- Quirine Fillekes
- Department of Pharmacy, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
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Purchase SE, Van der Linden DJ, McKerrow NH. Feasibility and effectiveness of early initiation of combination antiretroviral therapy in HIV-infected infants in a government clinic of Kwazulu-Natal, South Africa. J Trop Pediatr 2012; 58:114-9. [PMID: 21705764 DOI: 10.1093/tropej/fmr053] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A recent randomized trial showed dramatic improvement in survival of HIV-infected infants receiving early combination antiretroviral therapy (cART). However, few data are available for resource-limited settings. Therefore we conducted a chart review of HIV-infected infants initiated on cART between 2005 and 2008. Of 129 treated infants, 94 completed 6 months, 62 completed 12 months, and 39 completed 18 months of cART. Median age at initiation of cART was 8.6 months (range 2.1-11.9) and 77.2% had advanced disease. Undetectable VL was found in 78.8% of children who reached 18 months of treatment. CD4% increased from a median of 15.4% at baseline to 33.1% at 18 months. Weight for age Z-score increased from a mean ± SD of -2.7 ± 1.97 to 0.02 ± 1.10 at 18 months. Findings show favourable response to cART in HIV-infected infants outside a research environment, despite initial advanced disease. Efforts should be made to initiate cART as early as possible.
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Affiliation(s)
- Susan E Purchase
- Department of Paediatrics, Pietermarizburg Metropolitan Hospitals Complex, Pietermaritzburg, 3200, South Africa
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Muret P, Piedoux S, Solas C, Quaranta S. Niveau de preuve du suivi therapeutique pharmacologique de la névirapine. Therapie 2011; 66:187-95. [DOI: 10.2515/therapie/2011030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Accepted: 04/19/2011] [Indexed: 11/20/2022]
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Swaminathan S, Ramachandran G, Agibothu Kupparam HK, Mahalingam V, Soundararajan L, Perumal Kannabiran B, Navaneethapandian PGD, Shah I, Karunaianandham R, Sikhamani R. Factors influencing plasma nevirapine levels: a study in HIV-infected children on generic antiretroviral treatment in India. J Antimicrob Chemother 2011; 66:1354-9. [PMID: 21393201 DOI: 10.1093/jac/dkr075] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Nevirapine is an important component of paediatric combination HIV therapy. Adequate drug exposure is necessary in order to achieve long-lasting viral suppression. OBJECTIVES To study the influence of age, drug dose and formulation type, nutritional status and CYP2B6 516G>T polymorphism on blood concentrations of nevirapine in children treated with generic antiretroviral drugs. METHODS A multicentre study was conducted at four sites in India. HIV-infected children receiving generic nevirapine-based fixed-dose combinations were recruited. Trough and 2 h nevirapine plasma concentrations were determined by HPLC. Characterization of the CYP2B6 gene polymorphism was performed using direct sequencing. Clinical and nutritional status was recorded. Groups were compared using the Mann-Whitney U-test and multivariable logistic regression analysis was performed to identify factors contributing to low drug levels. RESULTS Ninety-four children of median age 78 months were studied; 60% were undernourished or stunted. Stunted children had a significantly lower 2 h nevirapine concentration compared with non-stunted children (P < 0.05); there were no significant differences in trough concentrations between different nutritional groups. Nevirapine levels were significantly higher in children with TT compared with GG and GT CYP2B6 genotypes (P < 0.01). Children ≤ 3 years had a 3.2 (95% confidence interval 1.07-9.45) times higher risk of having sub-therapeutic nevirapine concentrations. CONCLUSIONS Nevirapine blood concentrations are affected by many factors, most notably age ≤ 3 years; a combination of young age, stunting and CYP2B6 GG or GT genotype could potentially result in sub-therapeutic nevirapine concentrations. Dosing recommendations for children should be reviewed in the light of these findings.
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Affiliation(s)
- Soumya Swaminathan
- Tuberculosis Research Centre (Indian Council of Medical Research), Chennai, India.
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