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Daly MB, Wong-Sam A, Li L, Krovi A, Gatto GJ, Norton C, Luecke EH, Mrotz V, Forero C, Cottrell ML, Schauer AP, Gary J, Nascimento-Seixas J, Mitchell J, van der Straten A, Heneine W, Garcίa-Lerma JG, Dobard CW, Johnson LM. Pharmacokinetic Study of Islatravir and Etonogestrel Implants in Macaques. Pharmaceutics 2023; 15:2676. [PMID: 38140017 PMCID: PMC10747562 DOI: 10.3390/pharmaceutics15122676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 11/02/2023] [Accepted: 11/16/2023] [Indexed: 12/24/2023] Open
Abstract
The prevention of HIV and unintended pregnancies is a public health priority. Multi-purpose prevention technologies capable of long-acting HIV and pregnancy prevention are desirable for women. Here, we utilized a preclinical macaque model to evaluate the pharmacokinetics of biodegradable ε-polycaprolactone implants delivering the antiretroviral islatravir (ISL) and the contraceptive etonogestrel (ENG). Three implants were tested: ISL-62 mg, ISL-98 mg, and ENG-33 mg. Animals received one or two ISL-eluting implants, with doses of 42, 66, or 108 µg of ISL/day with or without an additional ENG-33 mg implant (31 µg/day). Drug release increased linearly with dose with median [range] plasma ISL levels of 1.3 [1.0-2.5], 1.9 [1.2-6.3] and 2.8 [2.3-11.6], respectively. The ISL-62 and 98 mg implants demonstrated stable drug release over three months with ISL-triphosphate (ISL-TP) concentr54ations in PBMCs above levels predicted to be efficacious for PrEP. Similarly, ENG implants demonstrated sustained drug release with median [range] plasma ENG levels of 495 [229-1110] pg/mL, which suppressed progesterone within two weeks and showed no evidence of altering ISL pharmacokinetics. Two of the six ISL-98 mg implants broke during the study and induced implant-site reactions, whereas no reactions were observed with intact implants. We show that ISL and ENG biodegradable implants are safe and yield sufficient drug levels to achieve prevention targets. The evaluation of optimized implants with increased mechanical robustness is underway for improved durability and vaginal efficacy in a SHIV challenge model.
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Affiliation(s)
- Michele B. Daly
- Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Andres Wong-Sam
- Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Linying Li
- RTI International, Durham, NC 27709, USA
| | | | | | | | | | - Victoria Mrotz
- Division of Scientific Resources, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Catalina Forero
- Division of Scientific Resources, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Mackenzie L. Cottrell
- Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Amanda P. Schauer
- Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Joy Gary
- Division of Scientific Resources, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Josilene Nascimento-Seixas
- Division of Scientific Resources, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - James Mitchell
- Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Ariane van der Straten
- ASTRA Consulting, Kensington, CA 94708, USA
- Center for AIDS Prevention Studies, Department of Medicine, University of California San Francisco, San Francisco, CA 94104, USA
| | - Walid Heneine
- Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - J. Gerardo Garcίa-Lerma
- Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - Charles W. Dobard
- Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
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Matoga M, Chen JS, Massa C, Thengolose I, Tegha G, Ndalama B, Bonongwe N, Mathiya E, Jere E, Banda G, Khan S, Loftis AJ, Kashuba A, Cottrell ML, Schauer AP, Van Horne B, Tompkins LA, Lancaster KE, Miller WC, Eron JJ, Hoffman IF, Cohen MS. HIV and urethritis: time required for antiretroviral therapy to suppress HIV in semen. AIDS 2023; 37:2233-2238. [PMID: 37534689 PMCID: PMC10621634 DOI: 10.1097/qad.0000000000003679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 07/20/2023] [Accepted: 07/28/2023] [Indexed: 08/04/2023]
Abstract
OBJECTIVES To examine the time required to suppress HIV in the genital tract with antiretroviral therapy (ART) in men with urethritis. DESIGN An observational cohort study. METHODS Men with HIV and urethritis not on ART were enrolled at an STI clinic in Malawi and offered to initiate ART. Blood and semen samples were collected pretreatment and at 1, 2, 4, 8, 12 and 24 weeks posturethritis treatment. Median viral loads (VLs) were calculated by ART initiation groups: 'within 1 week', 'between 1 and 4 weeks' and 'no ART before 4 weeks', based on the men's choice about whether or not to initiate ART. The presence of ART at each visit was confirmed by bioanalytical methods. FINDINGS Between January 2017 and November 2018, 74 men presented with urethritis and HIV and were confirmed ART naive. The median age was 32 years. Forty-one (55% of men) initiated ART within 1 week; 12 (16%) between 1 and 4 weeks; and 21 (28%) did not initiate ART by week 4. Within the 1 week group, median VL was suppressed within 4 weeks in both semen and blood. Among the 1-4 weeks group, VL was suppressed within 4 weeks in semen and 5 weeks in blood. Among the no ART before 4 weeks group, VL in semen declined within the first 4 weeks but remained unsuppressed through week 24, and there was no significant decline in blood HIV. CONCLUSION Treatment of urethritis and prompt initiation of ART with counseling for safer sex for at least one month is a critical measure to reduce transmission of HIV.
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Affiliation(s)
- Mitch Matoga
- University of North Carolina Project Malawi, Lilongwe, Malawi
| | - Jane S. Chen
- Institute for Global Health and Infectious Diseases
| | - Cecilia Massa
- University of North Carolina Project Malawi, Lilongwe, Malawi
| | | | - Gerald Tegha
- University of North Carolina Project Malawi, Lilongwe, Malawi
| | | | - Naomi Bonongwe
- University of North Carolina Project Malawi, Lilongwe, Malawi
| | - Esther Mathiya
- University of North Carolina Project Malawi, Lilongwe, Malawi
| | - Edward Jere
- University of North Carolina Project Malawi, Lilongwe, Malawi
| | - Gabriel Banda
- University of North Carolina Project Malawi, Lilongwe, Malawi
| | - Shiraz Khan
- University of North Carolina Project Malawi, Lilongwe, Malawi
| | | | - Angela Kashuba
- Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC
| | | | - Amanda P. Schauer
- Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC
| | - Brian Van Horne
- Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC
| | - Lauren A. Tompkins
- Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC
| | | | - William C. Miller
- The Ohio State University College of Public Health, Columbus, OH, USA
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3
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Fashe MM, Miner TA, Fallon JK, Schauer AP, Sykes C, Smith PC, Lee CR. Pregnancy related hormones increase CYP3A mediated buprenorphine metabolism in human hepatocytes: a comparison to CYP3A substrates nifedipine and midazolam. Front Pharmacol 2023; 14:1218703. [PMID: 37475714 PMCID: PMC10354249 DOI: 10.3389/fphar.2023.1218703] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 06/22/2023] [Indexed: 07/22/2023] Open
Abstract
Introduction: Pregnancy increases the clearance of CYP3A4 substrate drugs and pregnancy-related hormones (PRHs) induce hepatic CYP3A4 expression and metabolism. However, it remains unclear to what extent the magnitude of PRH-evoked changes in hepatic CYP3A metabolism varies across multiple substrates. This study quantified the impact of PRHs on CYP3A protein concentrations and buprenorphine metabolism in human hepatocytes, and compared the magnitude of these effects to nifedipine and midazolam metabolism. Methods: Sandwich-cultured human hepatocytes (SCHH) from female donors were exposed to PRHs, administered in combination across a range of physiologically relevant concentrations, for 72 h. Absolute protein concentrations of CYP3A4, CYP3A5, and CYP3A7 in SCHH membrane fractions were quantified by nanoLC-MS/MS, and norbuprenorphine (nor-BUP), dehydro-nifedipine (dehydro-NIF), and 1-hydroxy-midazolam (1-OH-MDZ) formation was evaluated. Results: Compared to control, PRH exposure increased CYP3A4, CYP3A7, and total CYP3A protein concentrations, but not CYP3A5 concentrations, and increased nor-BUP, dehydro-NIF, and 1-OH-MDZ formation in a concentration-dependent manner. The formation of nor-BUP, dehydro-NIF, and 1-OH-MDZ each positively correlated with PRH-mediated changes in total CYP3A protein concentrations. The PRH-evoked increase in nor-BUP formation was evident in all donors; however, the PRH induction of dehydro-NIF and 1-OH-MDZ formation was diminished in a hepatocyte donor with high basal CYP3A5 expression. Discussion: These findings demonstrate that PRHs increase buprenorphine, nifedipine, and midazolam metabolism in SCHH via induction of CYP3A4 and total CYP3A protein concentrations, and the magnitude of these effects vary across hepatocyte donors in a substrate-specific manner. These data provide insight into the contribution of PRH induction of CYP3A4 metabolism to increased buprenorphine clearance during pregnancy.
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Affiliation(s)
- Muluneh M. Fashe
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Taryn A. Miner
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - John K. Fallon
- Division of Pharmacoengineering and Molecular Pharmaceutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Amanda P. Schauer
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Craig Sykes
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Philip C. Smith
- Division of Pharmacoengineering and Molecular Pharmaceutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Craig R. Lee
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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Young IC, Thorson AL, Shrivastava R, Sykes C, Schauer AP, Cottrell ML, Kashuba ADM, Benhabbour SR. Dose-Ranging Plasma and Genital Tissue Pharmacokinetics and Biodegradation of Ultra-Long-Acting Cabotegravir In Situ Forming Implant. Pharmaceutics 2023; 15:1487. [PMID: 37242729 PMCID: PMC10222572 DOI: 10.3390/pharmaceutics15051487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 05/02/2023] [Accepted: 05/11/2023] [Indexed: 05/28/2023] Open
Abstract
HIV continues to affect millions of men and women worldwide. The development of long-acting injectables for HIV prevention can overcome adherence challenges with daily oral prevention regimens by reducing dosing frequency and stigma. We previously developed an ultra-long-acting injectable, biodegradable, and removeable in situ forming implant (ISFI) with cabotegravir (CAB) that demonstrated protection after multiple rectal SHIV challenges in female macaques. Here, we sought to further characterize CAB ISFI pharmacokinetics (PK) in mice by assessing the effect of dose and number of injections on CAB PK, time to completion of CAB release and polymer degradation, long-term genital tissue PK, and CAB PK tail after implant removal. CAB concentrations in plasma were above the benchmark for protection for 11-12 months with proportionality between dose and drug exposure. CAB ISFI exhibited high concentrations in vaginal, cervical, and rectal tissues for up to 180 days. Furthermore, depots were easily retrievable up to 180 days post-administration with up to 34% residual CAB and near complete (85%) polymer degradation quantified in depots ex vivo. After depot removal, results demonstrated a median 11-fold decline in CAB plasma concentrations across all doses. Ultimately, this study provided critical PK information for the CAB ISFI formulation that could aid in its future translation to clinical studies.
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Affiliation(s)
- Isabella C. Young
- Division of Pharmacoengineering and Molecular Pharmaceutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Allison L. Thorson
- Joint Department of Biomedical Engineering, North Carolina State University and The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Roopali Shrivastava
- Joint Department of Biomedical Engineering, North Carolina State University and The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Craig Sykes
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Amanda P. Schauer
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Mackenzie L. Cottrell
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Angela D. M. Kashuba
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Soumya Rahima Benhabbour
- Division of Pharmacoengineering and Molecular Pharmaceutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Joint Department of Biomedical Engineering, North Carolina State University and The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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5
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Devanathan AS, Dumond JB, Anderson DJC, Moody K, Poliseno AJ, Schauer AP, Sykes C, Gay CL, Rosen EP, Kashuba ADM, Cottrell ML. A Novel Algorithm to Improve PrEP Adherence Monitoring Using Dried Blood Spots. Clin Pharmacol Ther 2023; 113:896-903. [PMID: 36622798 PMCID: PMC10023501 DOI: 10.1002/cpt.2845] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 01/03/2023] [Indexed: 01/10/2023]
Abstract
Tenofovir diphosphate (TFVdp; an active metabolite of oral HIV pre-exposure prophylaxis (PrEP)) is measured in dried blood spots (DBS) to estimate adherence. However, TFVdp's long half-life in whole blood may lead to misclassification following a recent change in adherence. PrEP's other metabolite, emtricitabine triphosphate (FTCtp), has a shorter half-life in whole blood but adherence thresholds are undefined. We characterized DBS TFVdp and FTCtp concentrations across many dosing scenarios. Population pharmacokinetic models were fit to TFVdp and FTCtp DBS concentrations from a directly observed therapy study (NCT03218592). Concentrations were simulated for 90 days of daily dosing followed by 90 days of 1 to 7 doses/week and for event-driven PrEP (edPrEP) scenarios. Thresholds of 1,000 and 200 fmol/punch, for TFVdp and FTCtp, respectively, were reflective of taking 4 doses/week (a minimum target for effective PrEP in men). TFVdp was < 1,000 fmol/punch for 17 days after initiating daily PrEP and > 1,000 fmol/punch for 62 days after decreasing to 3 doses/week. Respectively, FTCtp was < 200 fmol/punch for 4 days and > 200 fmol/punch for 6 days. Accuracy of edPrEP adherence classification depended on duration between last sex act and DBS sampling for both measures with misclassification ranging from 9-100%. These data demonstrate adherence misclassification by DBS TFVdp for 2 months following a decline in adherence, elucidating the need for FTCtp to estimate recent adherence. We provide proof of principle that individualized interpretation is needed to support edPrEP adherence monitoring. Our collective approach facilitates clinicians' ability to interpret DBS results and administer patient-centric interventions.
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Affiliation(s)
- Aaron S. Devanathan
- University of North Carolina Eshelman School of Pharmacy, Chapel Hill, NC, USA
| | - Julie B. Dumond
- University of North Carolina Eshelman School of Pharmacy, Chapel Hill, NC, USA
| | - Daijha JC Anderson
- University of North Carolina Eshelman School of Pharmacy, Chapel Hill, NC, USA
| | - Kristen Moody
- University of North Carolina Eshelman School of Pharmacy, Chapel Hill, NC, USA
| | - Amanda J. Poliseno
- University of North Carolina Eshelman School of Pharmacy, Chapel Hill, NC, USA
| | - Amanda P. Schauer
- University of North Carolina Eshelman School of Pharmacy, Chapel Hill, NC, USA
| | - Craig Sykes
- University of North Carolina Eshelman School of Pharmacy, Chapel Hill, NC, USA
| | - Cynthia L. Gay
- University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Elias P. Rosen
- University of North Carolina Eshelman School of Pharmacy, Chapel Hill, NC, USA
| | - Angela DM Kashuba
- University of North Carolina Eshelman School of Pharmacy, Chapel Hill, NC, USA
- University of North Carolina School of Medicine, Chapel Hill, NC, USA
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6
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Schauer AP, Sykes C, Cottrell ML, Imaz A, Podzamczer D, Kashuba AD. Validation of an LC-MS/MS assay for the simultaneous determination of bictegravir, doravirine, and raltegravir in human plasma. J Pharm Biomed Anal 2022; 220:115010. [PMID: 36030752 DOI: 10.1016/j.jpba.2022.115010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 08/10/2022] [Accepted: 08/16/2022] [Indexed: 11/20/2022]
Abstract
Bictegravir (BIC), an integrase inhibitor, and doravirine (DOR), a non-nucleoside reverse transcriptase inhibitor, were recently approved by the US FDA for HIV treatment and are recommended first line treatment options. Because certain clinical scenarios warrant using them in combination, we developed a fully validated LC-MS/MS method for simultaneous measurement of BIC and DOR, along with a legacy integrase inhibitor, raltegravir (RAL), in human plasma over a clinically relevant 1000-fold range for each analyte. These analytes were extracted from the plasma by protein precipitation with their stable, isotopically labeled internal standards (BIC-d5, 13C6-DOR, and RAL-d6). Following extraction, samples were analyzed by reverse phase chromatography on a Waters Atlantis T3 C18 (50 ×2.1 mm, 3 µm particle size) column with subsequent detection by electrospray ionization in positive ion mode on an AB Sciex API-5000 triple quadrupole mass spectrometer. The assay was linear (R2 >0.994) over the selected calibration ranges (20.0-20,000 ng/mL (BIC), 3.00-3000 ng/mL (DOR), and 10.0-10,000 (RAL)). The assay was accurate (inter-assay %Bias ≤ ± 8.5) and precise (inter-assay %CV ≤11.4). This method was validated according to FDA guidance for industry and can be used to assess the pharmacokinetics of two newly approved antiretrovirals, or to support therapeutic drug monitoring for modern antiretroviral therapy.
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Affiliation(s)
- Amanda P Schauer
- Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
| | - Craig Sykes
- Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Mackenzie L Cottrell
- Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Arkaitz Imaz
- HIV and STI Unit, Department of Infectious Diseases, Bellvitge University Hospital, Bellvitge Biomedical Research Institute (IDIBELL), University of Barcelona, L'Hospitalet de Llobregat, Spain
| | - Daniel Podzamczer
- HIV and STI Unit, Department of Infectious Diseases, Bellvitge University Hospital, Bellvitge Biomedical Research Institute (IDIBELL), University of Barcelona, L'Hospitalet de Llobregat, Spain
| | - Angela Dm Kashuba
- Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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7
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Khatri R, Fallon JK, Sykes C, Kulick N, Rementer RJB, Miner TA, Schauer AP, Kashuba ADM, Boggess KA, Brouwer KLR, Smith PC, Lee CR. Pregnancy-Related Hormones Increase UGT1A1-Mediated Labetalol Metabolism in Human Hepatocytes. Front Pharmacol 2021; 12:655320. [PMID: 33995076 PMCID: PMC8115026 DOI: 10.3389/fphar.2021.655320] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 03/11/2021] [Indexed: 11/25/2022] Open
Abstract
Pregnancy-related hormones (PRH) are recognized as important regulators of hepatic cytochrome P450 enzyme expression and function. However, the impact of PRH on the hepatic expression and function of uridine diphosphate glucuronosyltransferases (UGTs) remains unclear. Using primary human hepatocytes, we evaluated the effect of PRH exposure on mRNA levels and protein concentrations of UGT1A1, UGT2B7, and other key UGT enzymes, and on the metabolism of labetalol (a UGT1A1 and UGT2B7 substrate commonly prescribed to treat hypertensive disorders of pregnancy). Sandwich-cultured human hepatocytes (SCHH) from female donors were exposed to the PRH estradiol, estriol, estetrol, progesterone, and cortisol individually or in combination. We quantified protein concentrations of UGT1A1, UGT2B7, and four additional UGT1A isoforms in SCHH membrane fractions and evaluated the metabolism of labetalol to its glucuronide metabolites in SCHH. PRH exposure increased mRNA levels and protein concentrations of UGT1A1 and UGT1A4 in SCHH. PRH exposure also significantly increased labetalol metabolism to its UGT1A1-derived glucuronide metabolite in a concentration-dependent manner, which positively correlated with PRH-induced changes in UGT1A1 protein concentrations. In contrast, PRH did not alter UGT2B7 mRNA levels or protein concentrations in SCHH, and formation of the UGT2B7-derived labetalol glucuronide metabolite was decreased following PRH exposure. Our findings demonstrate that PRH alter expression and function of UGT proteins in an isoform-specific manner and increase UGT1A1-mediated labetalol metabolism in human hepatocytes by inducing UGT1A1 protein concentrations. These results provide mechanistic insight into the increases in labetalol clearance observed in pregnant individuals.
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Affiliation(s)
- Raju Khatri
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - John K Fallon
- Division of Pharmacoengineering and Molecular Pharmaceutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Craig Sykes
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Natasha Kulick
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Rebecca J B Rementer
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Taryn A Miner
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Amanda P Schauer
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Angela D M Kashuba
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Kim A Boggess
- Department of Obstetrics and Gynecology, UNC School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Kim L R Brouwer
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Philip C Smith
- Division of Pharmacoengineering and Molecular Pharmaceutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Craig R Lee
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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8
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Guzman BB, Schauer AP, Dunn JA, Cottrell ML, Sykes C. A quantitative LC-MS/MS method for the determination of tissue brincidofovir and cidofovir diphosphate in a MuPyV-infected mouse model. Biomed Chromatogr 2021; 35:e5061. [PMID: 33398885 DOI: 10.1002/bmc.5061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 12/16/2020] [Accepted: 12/23/2020] [Indexed: 11/06/2022]
Abstract
Brincidofovir (BCV) is an investigational lipid conjugate of the nucleotide analog cidofovir (CDV), which is being developed as a medical countermeasure for the treatment of smallpox. BCV is active against double-stranded DNA viruses including BK and JC viruses. Here, we validated procedures for quantifying BCV and its pharmacologically active moiety cidofovir diphosphate (CDV-PP) in mouse kidney, brain and spleen tissue homogenates. Following homogenization, BCV and CDV-PP were extracted from the tissues by protein precipitation with their stable, isotopically labeled internal standards, BCV-d6 and 13 C3 15 N2 -CDV-PP. Then, samples were analyzed for BCV by reverse-phase chromatography on a Waters Xterra MS C18 (50 × 2.1 mm, 3.5 μm particle size) column while CDV-PP was analyzed on a Thermo BioBasic AX (50 × 2.1 mm, 5 μm particle size) column using anion exchange chromatography. Detection was achieved by electrospray ionization in positive ion mode on an AB Sciex API-5000 triple quadrupole mass spectrometer. The calibration curves were linear over a range of 1.00-1,000 ng/ml homogenate and 0.050-50.0 ng/ml homogenate for BCV and CDV-PP, respectively. These methods were validated according to US Food and Drug Administration guidance for industry and may be used to characterize the tissue pharmacology of both analytes to advance its preclinical development.
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Affiliation(s)
- Bryan B Guzman
- Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Amanda P Schauer
- Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | | | - Mackenzie L Cottrell
- Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Craig Sykes
- Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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9
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Cottrell ML, Prince HMA, Schauer AP, Sykes C, Maffuid K, Poliseno A, Chun TW, Huiting E, Stanczyk FZ, Peery AF, Dellon ES, Adams JL, Gay C, Kashuba ADM. Decreased Tenofovir Diphosphate Concentrations in a Transgender Female Cohort: Implications for Human Immunodeficiency Virus Preexposure Prophylaxis. Clin Infect Dis 2020; 69:2201-2204. [PMID: 30963179 DOI: 10.1093/cid/ciz290] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 04/04/2019] [Indexed: 12/21/2022] Open
Abstract
Feminizing hormone therapy (FHT) may interact with human immunodeficiency virus preexposure prophylaxis (PrEP). We found that transgender women who took FHT exhibited a 7-fold lower rectal tissue ratio of PrEP's active metabolites vs competing deoxynucleotides compared to cisgender women and men (P = .03) that inversely correlated with estradiol (ρ = -0.79; P < .05). Thus, FHT may negatively impact PrEP efficacy. Clinical Trials Registration . NCT02983110.
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Affiliation(s)
- Mackenzie L Cottrell
- Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics
| | - Heather M A Prince
- School of Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill
| | - Amanda P Schauer
- Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics
| | - Craig Sykes
- Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics
| | - Kaitlyn Maffuid
- Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics
| | - Amanda Poliseno
- Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics
| | - Tae-Wook Chun
- HIV Immunovirology Unit, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland
| | - Erin Huiting
- HIV Immunovirology Unit, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland
| | - Frank Z Stanczyk
- Keck School of Medicine, University of Southern California, Los Angeles
| | - Anne F Peery
- School of Medicine, Division of Gastroenterology and Hepatology, University of North Carolina at Chapel Hill
| | - Evan S Dellon
- School of Medicine, Division of Gastroenterology and Hepatology, University of North Carolina at Chapel Hill
| | - Jessica L Adams
- Philadelphia College of Pharmacy, University of the Sciences, Pennsylvania.,Cooper University Hospital Early Intervention Program, Camden, New Jersey
| | - Cindy Gay
- School of Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill
| | - Angela D M Kashuba
- Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics.,School of Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill
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10
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Dumond JB, Greene SA, Prince HMA, Chen J, Maas BM, Sykes C, Schauer AP, Blake KH, Nelson JAE, Gay CL, Kashuba ADM, Cohen MS. Differential extracellular, but similar intracellular, disposition of two tenofovir formulations in the male genital tract. Antivir Ther 2020; 24:45-50. [PMID: 30375984 DOI: 10.3851/imp3277] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/03/2018] [Indexed: 12/21/2022]
Abstract
BACKGROUND The male genital tract (MGT) is a viral sanctuary and likely HIV reservoir; understanding MGT pharmacokinetics (PK) of antiretrovirals (ARVs) used for curative strategies is critical to eradication and cure. Tenofovir alafenamide (TAF) is a tenofovir (TFV) formulation designed to maximize efficacy/minimize toxicity with unknown MGT PK. METHODS HIV-positive and HIV-negative men receiving TFV-based regimens provided six paired blood plasma (BP) and semen samples. Extracellular (TFV, TAF, emtricitabine [FTC]) drug concentrations in BP and seminal plasma (SP), and intracellular metabolite (IM) and endogenous nucleotide (EN) concentrations were measured in peripheral blood mononuclear cells (PBMCs) and seminal mononuclear cells (SMCs). Exposure ratios for SP:BP, SMC:PBMC and IM:EN were calculated from PK parameters generated by noncompartmental analysis. HIV viral load was measured in BP and SP. RESULTS Sixteen HIV-positive (n=8, TDF/FTC; n=8, TAF/FTC) and eight HIV-negative (TDF/FTC) men provided samples. Median TFV SP:BP ratios differed between TDF and TAF (1.5 versus 7.4), due to lower TFV BP concentrations with TAF coupled with TFV SP concentrations similar to TDF. FTC SP BP ratios were approximately 3. SMC concentrations of IMs and ENs were a fraction of PBMC concentrations (1-22%), though IM:EN ratios exceed a suggested protective threshold. CONCLUSIONS TAF SP PK was unexpected. IM SMC concentrations were low relative to PBMC, as were EN concentrations, suggesting differences in cell phenotype and lineage in the MGT; these differences in phenotype and pharmacology may have an impact on selecting and dosing ARVs used in cure strategies.
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Affiliation(s)
- Julie B Dumond
- UNC Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | | | - Heather M A Prince
- UNC School of Medicine, Department of Internal Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | | | - Brian M Maas
- Present address: Merck CO, Philadelphia, PA, USA
| | - Craig Sykes
- UNC Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Amanda P Schauer
- UNC Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Kimberly H Blake
- UNC Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Julie A E Nelson
- UNC School of Medicine, Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Cynthia L Gay
- UNC School of Medicine, Department of Internal Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Angela D M Kashuba
- UNC Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,UNC School of Medicine, Department of Internal Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Myron S Cohen
- UNC School of Medicine, Department of Internal Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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11
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Burgunder E, Fallon JK, White N, Schauer AP, Sykes C, Remling-Mulder L, Kovarova M, Adamson L, Luciw P, Garcia JV, Akkina R, Smith PC, Kashuba ADM. Antiretroviral Drug Concentrations in Lymph Nodes: A Cross-Species Comparison of the Effect of Drug Transporter Expression, Viral Infection, and Sex in Humanized Mice, Nonhuman Primates, and Humans. J Pharmacol Exp Ther 2019; 370:360-368. [PMID: 31235531 PMCID: PMC6695867 DOI: 10.1124/jpet.119.259150] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 06/19/2019] [Indexed: 12/21/2022] Open
Abstract
In a "kick and kill" strategy for human immunodeficiency virus (HIV) eradication, protective concentrations of antiretrovirals (ARVs) in the lymph node are important to prevent vulnerable cells from further HIV infection. However, the factors responsible for drug distribution and concentration into these tissues are largely unknown. Although humanized mice and nonhuman primates (NHPs) are crucial to HIV research, ARV tissue pharmacology has not been well characterized across species. This study investigated the influence of drug transporter expression, viral infection, and sex on ARV penetration within lymph nodes of animal models and humans. Six ARVs were dosed for 10 days in humanized mice and NHPs. Plasma and lymph nodes were collected at necropsy, 24 hours after the last dose. Human lymph node tissue and plasma from deceased patients were collected from tissue banks. ARV, active metabolite, and endogenous nucleotide concentrations were measured by liquid chromatography-tandem mass spectrometry, and drug transporter expression was measured using quantitative polymerase chain reaction and quantitative targeted absolute proteomics. In NHPs and humans, lymph node ARV concentrations were greater than or equal to plasma, and tenofovir diphosphate/deoxyadenosine triphosphate concentration ratios achieved efficacy targets in lymph nodes from all three species. There was no effect of infection or sex on ARV concentrations. Low drug transporter expression existed in lymph nodes from all species, and no predictive relationships were found between transporter gene/protein expression and ARV penetration. Overall, common preclinical models of HIV infection were well suited to predict human ARV exposure in lymph nodes, and low transporter expression suggests primarily passive drug distribution in these tissues. SIGNIFICANCE STATEMENT: During human immunodeficiency virus (HIV) eradication strategies, protective concentrations of antiretrovirals (ARVs) in the lymph node prevent vulnerable cells from further HIV infection. However, ARV tissue pharmacology has not been well characterized across preclinical species used for HIV eradication research, and the influence of drug transporters, HIV infection, and sex on ARV distribution and concentration into the lymph node is largely unknown. Here we show that two animal models of HIV infection (humanized mice and nonhuman primates) were well suited to predict human ARV exposure in lymph nodes. Additionally, we found that drug transporter expression was minimal and-along with viral infection and sex-did not affect ARV penetration into lymph nodes from any species.
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Affiliation(s)
- Erin Burgunder
- Eshelman School of Pharmacy (E.B., J.K.F., N.W., A.P.S., C.S., P.C.S., A.D.M.K.) and School of Medicine (M.K., J.V.G., A.D.M.K.), University of North Carolina, Chapel Hill, North Carolina; School of Medicine, Colorado State University, Fort Collins, Colorado (L.R.-M., R.A.); and School of Medicine, University of California, Davis, California (L.A., P.L.)
| | - John K Fallon
- Eshelman School of Pharmacy (E.B., J.K.F., N.W., A.P.S., C.S., P.C.S., A.D.M.K.) and School of Medicine (M.K., J.V.G., A.D.M.K.), University of North Carolina, Chapel Hill, North Carolina; School of Medicine, Colorado State University, Fort Collins, Colorado (L.R.-M., R.A.); and School of Medicine, University of California, Davis, California (L.A., P.L.)
| | - Nicole White
- Eshelman School of Pharmacy (E.B., J.K.F., N.W., A.P.S., C.S., P.C.S., A.D.M.K.) and School of Medicine (M.K., J.V.G., A.D.M.K.), University of North Carolina, Chapel Hill, North Carolina; School of Medicine, Colorado State University, Fort Collins, Colorado (L.R.-M., R.A.); and School of Medicine, University of California, Davis, California (L.A., P.L.)
| | - Amanda P Schauer
- Eshelman School of Pharmacy (E.B., J.K.F., N.W., A.P.S., C.S., P.C.S., A.D.M.K.) and School of Medicine (M.K., J.V.G., A.D.M.K.), University of North Carolina, Chapel Hill, North Carolina; School of Medicine, Colorado State University, Fort Collins, Colorado (L.R.-M., R.A.); and School of Medicine, University of California, Davis, California (L.A., P.L.)
| | - Craig Sykes
- Eshelman School of Pharmacy (E.B., J.K.F., N.W., A.P.S., C.S., P.C.S., A.D.M.K.) and School of Medicine (M.K., J.V.G., A.D.M.K.), University of North Carolina, Chapel Hill, North Carolina; School of Medicine, Colorado State University, Fort Collins, Colorado (L.R.-M., R.A.); and School of Medicine, University of California, Davis, California (L.A., P.L.)
| | - Leila Remling-Mulder
- Eshelman School of Pharmacy (E.B., J.K.F., N.W., A.P.S., C.S., P.C.S., A.D.M.K.) and School of Medicine (M.K., J.V.G., A.D.M.K.), University of North Carolina, Chapel Hill, North Carolina; School of Medicine, Colorado State University, Fort Collins, Colorado (L.R.-M., R.A.); and School of Medicine, University of California, Davis, California (L.A., P.L.)
| | - Martina Kovarova
- Eshelman School of Pharmacy (E.B., J.K.F., N.W., A.P.S., C.S., P.C.S., A.D.M.K.) and School of Medicine (M.K., J.V.G., A.D.M.K.), University of North Carolina, Chapel Hill, North Carolina; School of Medicine, Colorado State University, Fort Collins, Colorado (L.R.-M., R.A.); and School of Medicine, University of California, Davis, California (L.A., P.L.)
| | - Lourdes Adamson
- Eshelman School of Pharmacy (E.B., J.K.F., N.W., A.P.S., C.S., P.C.S., A.D.M.K.) and School of Medicine (M.K., J.V.G., A.D.M.K.), University of North Carolina, Chapel Hill, North Carolina; School of Medicine, Colorado State University, Fort Collins, Colorado (L.R.-M., R.A.); and School of Medicine, University of California, Davis, California (L.A., P.L.)
| | - Paul Luciw
- Eshelman School of Pharmacy (E.B., J.K.F., N.W., A.P.S., C.S., P.C.S., A.D.M.K.) and School of Medicine (M.K., J.V.G., A.D.M.K.), University of North Carolina, Chapel Hill, North Carolina; School of Medicine, Colorado State University, Fort Collins, Colorado (L.R.-M., R.A.); and School of Medicine, University of California, Davis, California (L.A., P.L.)
| | - J Victor Garcia
- Eshelman School of Pharmacy (E.B., J.K.F., N.W., A.P.S., C.S., P.C.S., A.D.M.K.) and School of Medicine (M.K., J.V.G., A.D.M.K.), University of North Carolina, Chapel Hill, North Carolina; School of Medicine, Colorado State University, Fort Collins, Colorado (L.R.-M., R.A.); and School of Medicine, University of California, Davis, California (L.A., P.L.)
| | - Ramesh Akkina
- Eshelman School of Pharmacy (E.B., J.K.F., N.W., A.P.S., C.S., P.C.S., A.D.M.K.) and School of Medicine (M.K., J.V.G., A.D.M.K.), University of North Carolina, Chapel Hill, North Carolina; School of Medicine, Colorado State University, Fort Collins, Colorado (L.R.-M., R.A.); and School of Medicine, University of California, Davis, California (L.A., P.L.)
| | - Philip C Smith
- Eshelman School of Pharmacy (E.B., J.K.F., N.W., A.P.S., C.S., P.C.S., A.D.M.K.) and School of Medicine (M.K., J.V.G., A.D.M.K.), University of North Carolina, Chapel Hill, North Carolina; School of Medicine, Colorado State University, Fort Collins, Colorado (L.R.-M., R.A.); and School of Medicine, University of California, Davis, California (L.A., P.L.)
| | - Angela D M Kashuba
- Eshelman School of Pharmacy (E.B., J.K.F., N.W., A.P.S., C.S., P.C.S., A.D.M.K.) and School of Medicine (M.K., J.V.G., A.D.M.K.), University of North Carolina, Chapel Hill, North Carolina; School of Medicine, Colorado State University, Fort Collins, Colorado (L.R.-M., R.A.); and School of Medicine, University of California, Davis, California (L.A., P.L.)
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12
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Greene SA, Chen J, Prince HMA, Sykes C, Schauer AP, Blake K, Nelson JAE, Gay CL, Cohen MS, Dumond JB. Population Modeling Highlights Drug Disposition Differences Between Tenofovir Alafenamide and Tenofovir Disoproxil Fumarate in the Blood and Semen. Clin Pharmacol Ther 2019; 106:821-830. [PMID: 31002391 DOI: 10.1002/cpt.1464] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 04/04/2019] [Indexed: 01/07/2023]
Abstract
Understanding antiretroviral disposition in the male genital tract, a distinct viral compartment, can provide insight for the eradication of HIV. Population pharmacokinetic modeling was conducted to investigate the disposition of tenofovir disoproxil fumarate (TDF), tenofovir alafenamide (TAF), and emtricitabine and their metabolites in blood and semen. Blood plasma and seminal plasma (SP) concentrations of tenofovir and emtricitabine were measured, as were tenofovir-diphosphate and emtricitabine-triphosphate concentrations in peripheral blood mononuclear cells (PBMCs) and seminal mononuclear cells. Sequential compartmental modeling described drug disposition in blood and semen. Our modeling suggests slower elimination of apparent tenofovir-diphosphate PBMC and faster elimination of tenofovir SP after administration of TAF compared with TDF, likely reflecting flip-flop kinetics. Additionally, TAF metabolism to tenofovir appeared slower in semen compared with blood; however, SP elimination of TAF-derived tenofovir appeared faster than its blood plasma elimination. These findings provide valuable insight for further mechanistic study of cellular entry and drug metabolism in the male genital tract.
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Affiliation(s)
- Stephen A Greene
- University of North Carolina (UNC), UNC Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.,SK Life Science, Inc, Fair Lawn, New Jersey, USA
| | - Jingxian Chen
- University of North Carolina (UNC), UNC Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.,Merck Co, Philadelphia, Pennsylvania, USA
| | - Heather M A Prince
- UNC School of Medicine, Department of Internal Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Craig Sykes
- University of North Carolina (UNC), UNC Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Amanda P Schauer
- University of North Carolina (UNC), UNC Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Kimberly Blake
- University of North Carolina (UNC), UNC Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Julie A E Nelson
- UNC School of Medicine, Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Cynthia L Gay
- UNC School of Medicine, Department of Internal Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Myron S Cohen
- UNC School of Medicine, Department of Internal Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Julie B Dumond
- University of North Carolina (UNC), UNC Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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13
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Srinivas N, Joseph SB, Robertson K, Kincer LP, Menezes P, Adamson L, Schauer AP, Blake KH, White N, Sykes C, Luciw P, Eron JJ, Forrest A, Price RW, Spudich S, Swanstrom R, Kashuba AD. Predicting Efavirenz Concentrations in the Brain Tissue of HIV-Infected Individuals and Exploring their Relationship to Neurocognitive Impairment. Clin Transl Sci 2019; 12:302-311. [PMID: 30675981 PMCID: PMC6510381 DOI: 10.1111/cts.12620] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 12/13/2018] [Indexed: 11/26/2022] Open
Abstract
Sparse data exist on the penetration of antiretrovirals into brain tissue. In this work, we present a framework to use efavirenz (EFV) pharmacokinetic (PK) data in plasma, cerebrospinal fluid (CSF), and brain tissue of eight rhesus macaques to predict brain tissue concentrations in HIV-infected individuals. We then perform exposure-response analysis with the model-predicted EFV area under the concentration-time curve (AUC) and neurocognitive scores collected from a group of 24 HIV-infected participants. Adult rhesus macaques were dosed daily with 200 mg EFV (as part of a four-drug regimen) for 10 days. Plasma was collected at 8 time points over 10 days and at necropsy, whereas CSF and brain tissue were collected at necropsy. In the clinical study, data were obtained from one paired plasma and CSF sample of participants prescribed EFV, and neuropsychological test evaluations were administered across 15 domains. PK modeling was performed using ADAPT version 5.0 Biomedical Simulation Resource, Los Angeles, CA) with the iterative two-stage estimation method. An eight-compartment model best described EFV distribution across the plasma, CSF, and brain tissue of rhesus macaques and humans. Model-predicted median brain tissue concentrations in humans were 31 and 8,000 ng/mL, respectively. Model-predicted brain tissue AUC was highly correlated with plasma AUC (γ = 0.99, P < 0.001) but not CSF AUC (γ = 0.34, P = 0.1) and did not show any relationship with neurocognitive scores (γ < 0.05, P > 0.05). This analysis provides an approach to estimate PK the brain tissue in order to perform PK/pharmacodynamic analyses at the target site.
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Affiliation(s)
- Nithya Srinivas
- Eshelman School of PharmacyUniversity of North Carolina at Chapel HillChapel HillNorth CarolinaUSA
- Present address:
Incyte CorporationWilmingtonDelawareUSA
| | - Sarah Beth Joseph
- School of MedicineUniversity of North Carolina at Chapel HillChapel HillNorth CarolinaUSA
| | - Kevin Robertson
- School of MedicineUniversity of North Carolina at Chapel HillChapel HillNorth CarolinaUSA
| | - Laura P. Kincer
- School of MedicineUniversity of North Carolina at Chapel HillChapel HillNorth CarolinaUSA
| | - Prema Menezes
- School of MedicineUniversity of North Carolina at Chapel HillChapel HillNorth CarolinaUSA
| | - Lourdes Adamson
- School of MedicineUniversity of CaliforniaDavisCaliforniaUSA
| | - Amanda P. Schauer
- Eshelman School of PharmacyUniversity of North Carolina at Chapel HillChapel HillNorth CarolinaUSA
| | - Kimberly H. Blake
- Eshelman School of PharmacyUniversity of North Carolina at Chapel HillChapel HillNorth CarolinaUSA
| | - Nicole White
- Eshelman School of PharmacyUniversity of North Carolina at Chapel HillChapel HillNorth CarolinaUSA
| | - Craig Sykes
- Eshelman School of PharmacyUniversity of North Carolina at Chapel HillChapel HillNorth CarolinaUSA
| | - Paul Luciw
- School of MedicineUniversity of CaliforniaDavisCaliforniaUSA
| | - Joseph J. Eron
- School of MedicineUniversity of North Carolina at Chapel HillChapel HillNorth CarolinaUSA
| | | | - Richard W. Price
- Department of NeurologySchool of MedicineUniversity of California San FranciscoSan FranciscoCaliforniaUSA
| | - Serena Spudich
- Department of NeurologyYale School of MedicineNew HavenConnecticutUSA
| | - Ronald Swanstrom
- School of MedicineUniversity of North Carolina at Chapel HillChapel HillNorth CarolinaUSA
| | - Angela D.M. Kashuba
- Eshelman School of PharmacyUniversity of North Carolina at Chapel HillChapel HillNorth CarolinaUSA
- School of MedicineUniversity of North Carolina at Chapel HillChapel HillNorth CarolinaUSA
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14
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Srinivas N, Rosen EP, Gilliland WM, Kovarova M, Remling-Mulder L, De La Cruz G, White N, Adamson L, Schauer AP, Sykes C, Luciw P, Garcia JV, Akkina R, Kashuba ADM. Antiretroviral concentrations and surrogate measures of efficacy in the brain tissue and CSF of preclinical species. Xenobiotica 2018; 49:1192-1201. [PMID: 30346892 DOI: 10.1080/00498254.2018.1539278] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
1. Antiretroviral concentrations in cerebrospinal fluid (CSF) are used as surrogate for brain tissue, although sparse data support this. We quantified antiretrovirals in brain tissue across preclinical models, compared them to CSF, and calculated 90% inhibitory quotients (IQ90) for nonhuman primate (NHP) brain tissue. Spatial distribution of efavirenz was performed by mass-spectrometry imaging (MSI). 2. HIV or RT-SHIV-infected and uninfected animals from two humanized mouse models (hemopoietic-stem cell/RAG2-, n = 36; bone marrow-liver-thymus/BLT, n =13) and an NHP model (rhesus macaque, n =18) were dosed with six antiretrovirals. Brain tissue, CSF (NHPs), and plasma were collected at necropsy. Drug concentrations were measured by LC-MS/MS. Rapid equilibrium dialysis determined protein binding in NHP brain. 3. Brain tissue penetration of most antiretrovirals were >10-fold lower (p < 0.02) in humanized mice than NHPs. NHP CSF concentrations were >13-fold lower (p <0.02) than brain tissue with poor agreement except for efavirenz (r = 0.91, p = 0.001). Despite 97% brain tissue protein binding, efavirenz achieved IQ90>1 in all animals and 2-fold greater white versus gray matter concentration. 4. Brain tissue penetration varied across animal models for all antiretrovirals except raltegravir, and extrapolating brain tissue concentrations between models should be avoided. With the exception of efavirenz, CSF is not a surrogate for brain tissue concentrations.
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Affiliation(s)
- Nithya Srinivas
- a Eshelman School of Pharmacy , University of North Carolina at Chapel Hill , Chapel Hill , NC , USA
| | - Elias P Rosen
- a Eshelman School of Pharmacy , University of North Carolina at Chapel Hill , Chapel Hill , NC , USA
| | - William M Gilliland
- a Eshelman School of Pharmacy , University of North Carolina at Chapel Hill , Chapel Hill , NC , USA
| | - Martina Kovarova
- b School of Medicine , University of North Carolina at Chapel Hill , Chapel Hill , NC , USA
| | | | - Gabriela De La Cruz
- b School of Medicine , University of North Carolina at Chapel Hill , Chapel Hill , NC , USA
| | - Nicole White
- a Eshelman School of Pharmacy , University of North Carolina at Chapel Hill , Chapel Hill , NC , USA
| | - Lourdes Adamson
- d School of Medicine , University of California at Davis , Davis , CA , USA
| | - Amanda P Schauer
- a Eshelman School of Pharmacy , University of North Carolina at Chapel Hill , Chapel Hill , NC , USA
| | - Craig Sykes
- a Eshelman School of Pharmacy , University of North Carolina at Chapel Hill , Chapel Hill , NC , USA
| | - Paul Luciw
- d School of Medicine , University of California at Davis , Davis , CA , USA
| | - J Victor Garcia
- b School of Medicine , University of North Carolina at Chapel Hill , Chapel Hill , NC , USA
| | - Ramesh Akkina
- c School of Medicine , Colorado State University , Fort Collins , CO , USA
| | - Angela D M Kashuba
- a Eshelman School of Pharmacy , University of North Carolina at Chapel Hill , Chapel Hill , NC , USA
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15
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Sykes C, Blake K, White N, Schauer AP, Guzman BB, Cottrell ML, Tamraz B, Kashuba ADM. Development and validation of an LC-MS/MS assay for the quantification of dolutegravir extracted from human hair. Anal Bioanal Chem 2018; 410:7773-7781. [PMID: 30280227 DOI: 10.1007/s00216-018-1394-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 09/12/2018] [Accepted: 09/20/2018] [Indexed: 11/29/2022]
Abstract
Measurement of drug concentrations in hair provides a non-invasive approach to assess drug adherence. Here, we report on the development and validation of a method for the quantification of the antiretroviral dolutegravir (DTG) extracted from human hair. DTG is extracted from hair samples by sonication and incubation in 50:50 methanol:acetonitrile with 2% formic acid overnight at 40 °C. Following extraction, samples are analyzed by reverse-phase chromatography on a Waters Atlantis T3 (50 × 2.1 mm, 3-μm particle size) column with subsequent detection by electrospray ionization in positive ion mode on an AB Sciex API-5000 triple quadrupole mass spectrometer. The stable, isotopically labeled 13C,d5-DTG is used as an internal standard in the assay. The calibration range is 5-10,000 pg DTG/mL of extraction solvent with the ability to extract between 1 and 10 mg of hair/mL of extraction solvent. The assay was linear, accurate (inter-assay %bias within ± 6.5%), and precise (inter-assay %CV ≤ 10.3%). The assay was successfully used to analyze clinical samples from subjects on DTG regimens. Analysis of clinical samples suggested the potential presence of a degradation product, which was subsequently confirmed to occur with exposure to sunlight. The degradation of DTG could complicate absolute interpretation of clinical results, but the presence of this degradation product is easily evaluated with this assay to aid in data interpretation.
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Affiliation(s)
- Craig Sykes
- Division of Pharmacotherapy and Experimental Therapeutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, 1099C Genetic Medicine Building, CB# 7361, 120 Mason Farm Road, Chapel Hill, NC, 27599, USA.
| | - Kimberly Blake
- Division of Pharmacotherapy and Experimental Therapeutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, 1099C Genetic Medicine Building, CB# 7361, 120 Mason Farm Road, Chapel Hill, NC, 27599, USA
| | - Nicole White
- Division of Pharmacotherapy and Experimental Therapeutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, 1099C Genetic Medicine Building, CB# 7361, 120 Mason Farm Road, Chapel Hill, NC, 27599, USA
| | - Amanda P Schauer
- Division of Pharmacotherapy and Experimental Therapeutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, 1099C Genetic Medicine Building, CB# 7361, 120 Mason Farm Road, Chapel Hill, NC, 27599, USA
| | - Bryan B Guzman
- Division of Pharmacotherapy and Experimental Therapeutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, 1099C Genetic Medicine Building, CB# 7361, 120 Mason Farm Road, Chapel Hill, NC, 27599, USA
| | - Mackenzie L Cottrell
- Division of Pharmacotherapy and Experimental Therapeutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, 1099C Genetic Medicine Building, CB# 7361, 120 Mason Farm Road, Chapel Hill, NC, 27599, USA
| | - Bani Tamraz
- Department of Clinical Pharmacy, University of California, San Francisco, School of Pharmacy, San Francisco, California, 94117, USA
| | - Angela D M Kashuba
- Division of Pharmacotherapy and Experimental Therapeutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, 1099C Genetic Medicine Building, CB# 7361, 120 Mason Farm Road, Chapel Hill, NC, 27599, USA
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Garrett KL, Chen J, Maas BM, Cottrell ML, Prince HA, Sykes C, Schauer AP, White N, Dumond JB. A Pharmacokinetic/Pharmacodynamic Model to Predict Effective HIV Prophylaxis Dosing Strategies for People Who Inject Drugs. J Pharmacol Exp Ther 2018; 367:245-251. [PMID: 30150483 DOI: 10.1124/jpet.118.251009] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 08/22/2018] [Indexed: 11/22/2022] Open
Abstract
The goal of this work was to evaluate dosing strategies for tenofovir disoproxil fumarate (TDF), tenofovir alafenamide (TAF), and emtricitabine (FTC) for pre-exposure prophylaxis (PrEP) with injection drug use with a pharmacokinetic/pharmacodynamics analysis of concentration data generated from two single-dose clinical studies conducted in healthy women. Population pharmacokinetic models were developed using measured intracellular metabolite, endogenous nucleotide competitors, and extracellular parent drug concentrations. Intracellular metabolite concentrations were normalized to endogenous competitors and compared with an EC90 target for PrEP efficacy. Monte Carlo simulations were used to select effective dose strategies of single agents (TAF, TDF, and FTC) and combinations (TDF + FTC and TAF + FTC). Daily, intermittent, and event-driven dosing regimens at varying dosage amounts were explored. When combined, TDF + FTC and TAF + FTC both provided quick (0.5 hours) and durable (up to 84 and 108 hours, respectively) protection of ≥99% after a single dose. When dosed twice per week, protection remained at 100%. Single-agent regimens provided lower estimates of protection than either combination tested. Here, the application of pharmacokinetic modeling to in vitro target concentrations demonstrates the added utility of including FTC in a successful PrEP regimen. While no TAF-based PrEP data are currently available for comparison, this analysis suggests TAF + FTC could completely protect against percutaneous exposure with as little as two doses per week.
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Affiliation(s)
- Katy L Garrett
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy (K.L.G., J.C., B.M.M., M.L.C., C.S., A.P.S., J.B.D.), and School of Medicine (H.A.P., N.W.), University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Jingxian Chen
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy (K.L.G., J.C., B.M.M., M.L.C., C.S., A.P.S., J.B.D.), and School of Medicine (H.A.P., N.W.), University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Brian M Maas
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy (K.L.G., J.C., B.M.M., M.L.C., C.S., A.P.S., J.B.D.), and School of Medicine (H.A.P., N.W.), University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Mackenzie L Cottrell
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy (K.L.G., J.C., B.M.M., M.L.C., C.S., A.P.S., J.B.D.), and School of Medicine (H.A.P., N.W.), University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Heather A Prince
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy (K.L.G., J.C., B.M.M., M.L.C., C.S., A.P.S., J.B.D.), and School of Medicine (H.A.P., N.W.), University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Craig Sykes
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy (K.L.G., J.C., B.M.M., M.L.C., C.S., A.P.S., J.B.D.), and School of Medicine (H.A.P., N.W.), University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Amanda P Schauer
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy (K.L.G., J.C., B.M.M., M.L.C., C.S., A.P.S., J.B.D.), and School of Medicine (H.A.P., N.W.), University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Nicole White
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy (K.L.G., J.C., B.M.M., M.L.C., C.S., A.P.S., J.B.D.), and School of Medicine (H.A.P., N.W.), University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Julie B Dumond
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy (K.L.G., J.C., B.M.M., M.L.C., C.S., A.P.S., J.B.D.), and School of Medicine (H.A.P., N.W.), University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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Schauer AP, Sykes C, Cottrell ML, Prince H, Kashuba ADM. Validation of an LC-MS/MS assay to simultaneously monitor the intracellular active metabolites of tenofovir, emtricitabine, and lamivudine in dried blood spots. J Pharm Biomed Anal 2017; 149:40-45. [PMID: 29100029 DOI: 10.1016/j.jpba.2017.10.030] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 10/25/2017] [Accepted: 10/26/2017] [Indexed: 01/16/2023]
Abstract
The ability to monitor adherence to antiretroviral therapy is critical for the interpretation of outcomes from clinical studies of HIV, and for optimizing patient care. The antiretrovirals tenofovir (TFV), emtricitabine (FTC), and lamivudine (3TC) are commonly included in drug regimens for HIV prevention and treatment. The active form of the drugs tenofovir diphosphate (TFVdp), emtricitabine triphosphate (FTCtp), and lamivudine triphosphate (3TCtp) are found intracellularly in erythrocytes and peripheral blood mononuclear cells (PBMCs). The ability to collect and analyze dried blood spot (DBS) samples is an attractive alternative to PBMC sampling in many resource limited settings. We developed and validated an assay to quantify all three intracellular metabolites over the range of 100-25000 fmol/sample. This assay utilizes a simple protein precipitation/liquid-liquid extraction of a single 3-mm DBS punch (from a Whatman 903 Protein Saver card) with isotopically labeled 13C5-TFVdp included as the internal standard. Following extraction, samples are analyzed by anion exchange chromatography on a Thermo Biobasic AX 5μm column with detection by electrospray ionization in the positive mode on a AB Sciex API-5000 triple quadrupole mass spectrometer with a total run time of 8min. The assay was linear over the entire range (R2>0.996). The assay was accurate (inter-assay%bias within ±3.0%) and precise (inter-assay % CV≤9.8%). The assay was also reproducible from multiple punches within a spot as well as punches from separate blood spots. Stability was established at room temperature for 3days, and at -80°C for up to 63days. Clinical samples were analyzed from subjects on Truvada®, Stribild®, Descovy®, and Triumeq® regimens and intracellular metabolites were detected in all samples as expected, indicating the assay performs well for all current formulations of TFV, FTC, and 3TC.
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Affiliation(s)
- Amanda P Schauer
- Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Eshelman School of Pharmacy, Chapel Hill, NC 27599, United States.
| | - Craig Sykes
- Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Eshelman School of Pharmacy, Chapel Hill, NC 27599, United States
| | - Mackenzie L Cottrell
- Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Eshelman School of Pharmacy, Chapel Hill, NC 27599, United States
| | - Heather Prince
- School of Medicine, University of North Carolina at Chapel Hill, Genetic Medicine Building, CB# 7361, 120 Mason Farm Road, Chapel Hill, NC 27599, United States
| | - Angela D M Kashuba
- Division of Pharmacotherapy and Experimental Therapeutics, University of North Carolina at Chapel Hill, Eshelman School of Pharmacy, Chapel Hill, NC 27599, United States
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