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García-Lerma JG, McNicholl JM, Heneine W. The predictive value of macaque models of preexposure prophylaxis for HIV prevention. Curr Opin HIV AIDS 2022; 17:179-85. [PMID: 35762371 DOI: 10.1097/COH.0000000000000738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE OF REVIEW We review macaque models for preexposure prophylaxis (PrEP) for HIV prevention and highlight their role in advancing currently approved and novel PrEP agents. RECENT FINDINGS The development of the repeat low dose simian HIV (SHIV) challenge models represented a significant advancement in preclinical PrEP modeling that has allowed the investigation of PrEP under conditions that better mimic HIV exposures in humans. These models incorporate relevant drug pharmacology to inform drug correlates of PrEP protection. Models of rectal, vaginal, and penile infection are now available and have been found to predict clinical efficacy of all the currently approved PrEP strategies including daily oral PrEP with the combination of emtricitabine and tenofovir disoproxil fumarate or tenofovir alafenamide, and a long-acting formulation of the integrase inhibitor cabotegravir. These models are being used to test new PrEP modalities including the nucleoside reverse transcriptase-translocation inhibitor islatravir and long-acting capsid inhibitors. The SHIV models have also been supplemented by sexually transmitted infection co-infections with Chlamydia trachomatis, Treponema pallidum or Trichomonas vaginalis to assess the impact of inflammation on PrEP efficacy. SUMMARY Clinical efficacy validated current PrEP macaque models supporting their continued use to advance novel PrEP agents to improve global PrEP coverage.
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Jayachandran P, Garcia-Cremades M, Vučićević K, Bumpus NN, Anton P, Hendrix C, Savić R. A Mechanistic In Vivo/Ex Vivo Pharmacokinetic-Pharmacodynamic Model of Tenofovir for HIV Prevention. CPT Pharmacometrics Syst Pharmacol 2021; 10:179-187. [PMID: 33547874 PMCID: PMC7965838 DOI: 10.1002/psp4.12583] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: 10/12/2020] [Accepted: 11/04/2020] [Indexed: 12/24/2022] Open
Abstract
Defining tissue and plasma-specific prophylactic drug concentrations is central to pre-exposure prophylaxis product development for sexual transmission of HIV-1. Pharmacokinetic (PK) data from study RMP-02/MTN-006 comparing single dose oral tenofovir disoproxil fumarate with single and multiple dose rectal tenofovir (TFV) gel administration in HIV-1 seronegative adults was used to construct a multicompartment plasma-rectal tissue population PK model for TFV and tenofovir-diphosphate (TFVdp) in plasma and rectal tissue. PK data were collected in five matrices: TFV (plasma, rectal tissue homogenate), TFVdp (peripheral blood mononuclear cells, rectal mononuclear cells (MMCs), rectal tissue homogenate). A viral growth compartment and a delayed effect compartment for p24 antigen expression measured from an ex vivo explant assay described HIV-1 infection and replication. Using a linear PK/pharmacodynamic model, MMC TFVdp levels over 9,000 fmol/million cells in the explant assay provided apparent viral replication suppression down to 1%. Parameters were estimated using NONMEM version 7.4.
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Affiliation(s)
- Priya Jayachandran
- Department of Bioengineering and Therapeutic SciencesUniversity of California San FranciscoSan FranciscoCaliforniaUSA
| | - Maria Garcia-Cremades
- Department of Bioengineering and Therapeutic SciencesUniversity of California San FranciscoSan FranciscoCaliforniaUSA
| | - Katarina Vučićević
- Department of Bioengineering and Therapeutic SciencesUniversity of California San FranciscoSan FranciscoCaliforniaUSA
- Department of Pharmacokinetics and Clinical PharmacyFaculty of PharmacyUniversity of BelgradeBelgradeSerbia
| | - Namandjé N. Bumpus
- Division of Clinical PharmacologyDepartment of MedicineJohns Hopkins UniversityBaltimoreMarylandUSA
| | - Peter Anton
- University of California Los AngelesLos AngelesCaliforniaUSA
| | - Craig Hendrix
- Division of Clinical PharmacologyDepartment of MedicineJohns Hopkins UniversityBaltimoreMarylandUSA
| | - Radojka Savić
- Department of Bioengineering and Therapeutic SciencesUniversity of California San FranciscoSan FranciscoCaliforniaUSA
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3
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Herrera C. The Pre-clinical Toolbox of Pharmacokinetics and Pharmacodynamics: in vitro and ex vivo Models. Front Pharmacol 2019; 10:578. [PMID: 31178736 PMCID: PMC6543330 DOI: 10.3389/fphar.2019.00578] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 05/06/2019] [Indexed: 01/05/2023] Open
Abstract
Prevention strategies against sexual transmission of human immunodeficiency virus (HIV) are essential to curb the rate of new infections. In the absence of a correlate of protection against HIV infection, pre-clinical evaluation is fundamental to facilitate and accelerate prioritization of prevention candidates and their formulations in a rapidly evolving clinical landscape. Characterization of pharmacokinetic (PK) and pharmacodynamic (PD) properties for candidate inhibitors is the main objective of pre-clinical evaluation. in vitro and ex vivo systems for pharmacological assessment allow experimental flexibility and adaptability at a relatively low cost without raising as significant ethical concerns as in vivo models. Applications and limitations of pre-clinical PK/PD models and future alternatives are reviewed in the context of HIV prevention.
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Affiliation(s)
- Carolina Herrera
- Section of Virology, Division of Infectious Diseases, Department of Medicine, Faculty of Medicine, Imperial College London, London, United Kingdom
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4
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Seneviratne HK, Hendrix CW, Fuchs EJ, Bumpus NN. MALDI Mass Spectrometry Imaging Reveals Heterogeneous Distribution of Tenofovir and Tenofovir Diphosphate in Colorectal Tissue of Subjects Receiving a Tenofovir-Containing Enema. J Pharmacol Exp Ther 2018; 367:40-48. [PMID: 30037813 DOI: 10.1124/jpet.118.250357] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 07/18/2018] [Indexed: 01/21/2023] Open
Abstract
Efforts to prevent human immunodeficiency virus (HIV) infection via pre-exposure prophylaxis (PrEP) include the development of anti-HIV drugs as microbicides for topical application to the mucosal sites of infection; however, although understanding the distribution profiles of these drugs in target mucosal tissues is of critical importance to guiding their optimization, data in this regard are largely lacking. With this in mind, we developed a matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) approach to visualize tenofovir (TFV), an HIV nucleotide analog reverse-transcriptase inhibitor under investigation for use as a topical microbicide, and its active metabolite TFV-diphosphate (TFV-DP) in colorectal biopsies obtained from healthy volunteers who received TFV-containing enemas. Application of MALDI MSI resulted in sufficient spatial resolution to visualize both TFV and TFV-DP and revealed heterogeneity in the distribution profiles of both analytes, including the presence of regions in which TFV and TFV-DP were undetectable, in colorectal tissue at two different time points and concentrations. Cell-specific staining for CD4 T and CD11c dendritic cells, which are important to the establishment of HIV infection, demonstrated that the TFV and TFV-DP distributions were independent of these cell types. MALDI MSI of endogenous lipids demonstrated that the heterogeneity observed for TFV and TFV-DP was not a function of tissue composition or processing. These data provide unique insight into the spatial distribution of TFV and TFV-DP in human colorectal tissue. In addition, this work establishes an approach that can be leveraged to directly detect and visualize these clinically important analytes more broadly in tissue.
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Affiliation(s)
- Herana Kamal Seneviratne
- Department of Medicine, Division of Clinical Pharmacology, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Craig W Hendrix
- Department of Medicine, Division of Clinical Pharmacology, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Edward J Fuchs
- Department of Medicine, Division of Clinical Pharmacology, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Namandjé N Bumpus
- Department of Medicine, Division of Clinical Pharmacology, The Johns Hopkins University School of Medicine, Baltimore, Maryland
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5
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Presnell AL, Chuchuen O, Simons MG, Maher JR, Katz DF. Full depth measurement of tenofovir transport in rectal mucosa using confocal Raman spectroscopy and optical coherence tomography. Drug Deliv Transl Res 2018; 8:843-852. [PMID: 29468424 PMCID: PMC6042643 DOI: 10.1007/s13346-018-0495-7] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The prophylactic activity of antiretroviral drugs applied as microbicides against sexually transmitted HIV is dependent upon their concentrations in infectable host cells. Within mucosal sites of infection (e.g., vaginal and rectal mucosa), those cells exist primarily in the stromal layer of the tissue. Traditional pharmacokinetic studies of these drugs have been challenged by poor temporal and spatial specificity. Newer techniques to measure drug concentrations, involving Raman spectroscopy, have been limited by laser penetration depth into tissue. Utilizing confocal Raman spectroscopy (RS) in conjunction with optical coherence tomography (OCT), a new lateral imaging assay enabled concentration distributions to be imaged with spatial and temporal specificity throughout the full depth of a tissue specimen. The new methodology was applied in rectal tissue using a clinical rectal gel formulation of 1% tenofovir (TFV). Confocal RS revealed diffusion-like behavior of TFV through the tissue specimen, with significant partitioning of the drug at the interface between the stromal and adipose tissue layers. This has implications for drug delivery to infectable tissue sites. The new assay can be applied to rigorously analyze microbicide transport and delineate fundamental transport parameters of the drugs (released from a variety of delivery vehicles) throughout the mucosa, thus informing microbicide product design.
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Affiliation(s)
- Aubrey L Presnell
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| | - Oranat Chuchuen
- Department of Biotechnology, Faculty of Technology, Khon Kaen University, Khon Kaen, 40002, Thailand
- Mekong Health Science Research Institute, Khon Kaen University, Khon Kaen, 40002, Thailand
| | - Morgan G Simons
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| | - Jason R Maher
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| | - David F Katz
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA.
- Department of Obstetrics and Gynecology, Duke University, Durham, NC, 27708, USA.
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Hoang T, Date AA, Ortiz JO, Young TW, Bensouda S, Xiao P, Marzinke M, Rohan L, Fuchs EJ, Hendrix C, Gumber S, Villinger F, Cone RA, Hanes J, Ensign LM. Development of rectal enema as microbicide (DREAM): Preclinical progressive selection of a tenofovir prodrug enema. Eur J Pharm Biopharm 2019; 138:23-9. [PMID: 29802984 DOI: 10.1016/j.ejpb.2018.05.030] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 05/14/2018] [Accepted: 05/22/2018] [Indexed: 12/22/2022]
Abstract
HIV pre-exposure prophylaxis (PrEP) strategies have the potential to prevent millions of incident HIV infections each year. However, the efficacy of PrEP strategies has been plagued by issues of non-adherence, likely because of the difficulty in motivating otherwise healthy people to adhere to treatment regimens that require significant behavioral changes and daily discipline. An alternative approach to PrEP is to focus on strategies that fit in to normal, and even desirable, sexual behaviors, such as the use of cleansing enemas by men who have sex with men (MSM) prior to receptive anal intercourse (RAI). Here, we describe preclinical efforts toward optimizing a tenofovir (TFV)-based enema formulation for rectal PrEP. Using a murine model, we compared the plasma and tissue pharmacokinetics of TFV and various TFV prodrugs, including tenofovir disoproxil fumarate (TDF), tenofovir alafenamide (TAF), and hexadecyloxypropyl tenofovir (CMX157), after dosing as enema formulations with varying osmolality and ion content. We observed that the enema vehicle composition played a more important role than the TFV prodrug properties in achieving rapid and therapeutically relevant tenofovir diphosphate (TFV-DP) concentrations in mouse colorectal tissue. Our results support the next steps, which are further preclinical (non-human primate) and clinical development of a hypo-osmolar TFV enema product for rectal PrEP.
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7
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Robinson JA, Marzinke MA, Fuchs EJ, Bakshi RP, Spiegel HML, Coleman JS, Rohan LC, Hendrix CW. Comparison of the Pharmacokinetics and Pharmacodynamics of Single-Dose Tenofovir Vaginal Film and Gel Formulation (FAME 05). J Acquir Immune Defic Syndr 2018; 77:175-182. [PMID: 29135651 PMCID: PMC5821271 DOI: 10.1097/qai.0000000000001587] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [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] [Indexed: 12/26/2022]
Abstract
OBJECTIVE Although preexposure prophylaxis with oral tenofovir (TFV) disoproxil fumarate/emtricitabine reduces HIV acquisition rates, poor adherence to and acceptability of daily vaginal gels have led to development of vaginal film formulations to improve adherence and, potentially, to enable episodic use. STUDY DESIGN In this 2-arm, cross-over study of a fast-dissolving tenofovir film (40 mg) compared with a previously studied semisolid tenofovir 1% gel (40 mg), 10 healthy women received a single vaginal dose of each study product. Clinical, pharmacokinetic, and antiviral assessments were performed over 1 week after dose. RESULTS Nine of 10 participants experienced mild to moderate adverse effects, similar between products, with no severe adverse events or events attributed to study products. TFV concentrations after film dosing exceeded concentrations after gel dosing in plasma between 8 and 24 hours (P ≤ 0.02). TFV concentrations in cervicovaginal fluid and both TFV and TFV diphosphate concentrations in cervical tissue homogenates were higher after film dosing (all P values < 0.04). The differences ranged from median (interquartile range) 2.9-fold (1.1, 9.0; midvaginal cervicovaginal fluid) to 4.4-fold (2.9, 7.7; plasma). Neither film nor gel demonstrated reduced cervical tissue biopsy infectivity after ex vivo HIV challenge. CONCLUSION Single-dose tenofovir film demonstrated consistently higher concentrations in plasma and cervicovaginal samples when compared with gel during the first day after dosing. Single-dose cervical tissue TFV-diphosphate concentrations at 5 hours exceeded steady-state concentrations previously reported with daily oral Truvada dosing. Tenofovir film may provide an alternative to tenofovir oral and gel formulations. Clinical efficacy remains to be tested.
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Affiliation(s)
- Jennifer A. Robinson
- Department of Gynecology and Obstetrics, Johns Hopkins University, Baltimore, Maryland
- Department of Medicine (Clinical Pharmacology), Johns Hopkins University, Baltimore, Maryland
| | - Mark A. Marzinke
- Department of Pathology, Johns Hopkins University, Baltimore, Maryland
- Department of Medicine (Clinical Pharmacology), Johns Hopkins University, Baltimore, Maryland
| | - Edward J. Fuchs
- Department of Medicine (Clinical Pharmacology), Johns Hopkins University, Baltimore, Maryland
| | - Rahul P. Bakshi
- Department of Medicine (Clinical Pharmacology), Johns Hopkins University, Baltimore, Maryland
| | - Hans M. L. Spiegel
- Kelly Government Solutions, Contractor to Division of AIDS, PMPRB/Prevention Sciences Program, Division of AIDS, NIAID, NIH, Rockville, MD
| | - Jenell S. Coleman
- Department of Gynecology and Obstetrics, Johns Hopkins University, Baltimore, Maryland
| | - Lisa C. Rohan
- Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania
- Magee-Womens Research Institute, Pittsburgh, Pennsylvania
| | - Craig W. Hendrix
- Department of Medicine (Clinical Pharmacology), Johns Hopkins University, Baltimore, Maryland
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8
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Dezzutti CS, Park SY, Marks KM, Lawlor SE, Russo JR, Macio I, Chappell CA, Bunge KE. Heterogeneity of HIV-1 Replication in Ectocervical and Vaginal Tissue Ex Vivo. AIDS Res Hum Retroviruses 2018; 34:185-192. [PMID: 28982249 DOI: 10.1089/aid.2017.0107] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [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: 01/17/2023] Open
Abstract
In clinical trials evaluating HIV-1 prevention products, ex vivo exposure of mucosal tissue to HIV-1 is performed to inform drug levels needed to suppress viral infection. Understanding assay and participant variables that influence HIV-1 replication will help with assay implementation. Demographic and behavioral data were obtained from 61 healthy women aged 21-45. Paired cervical tissue (CT) and vaginal tissue (VT) biopsies were collected and treated with HIV-1BaL or HIV-1JR-CSF, washed, and cultured. On days 3, 7, and/or 11, culture supernatant was collected, and viral replication was monitored by p24 ELISA. Tissue was extracted at study end, and HIV-1 relative RNA copies were determined by polymerase chain reaction. Cumulative p24 and RNA were log-transformed and analyzed using a linear mixed model, t-test, and an intraclass correlation coefficient (ICC). HIV replication was similar between CT and VT for each virus, but HIV-1BaL had 1.5 log10 and 0.9 log10 higher levels of p24 than HIV-1JR-CSF in CT and VT, respectively (p < .001), which correlated with HIV-1 relative RNA copies. Cumulative p24 and RNA copies in both tissues demonstrated low intraperson correlation for both viruses (ICC ≤0.513 HIV-1BaL; ICC ≤0.419 HIV-1JR-CSF). Enrollment into previous clinical studies in which genital biopsies were collected modestly decreased the HIV-1BaL cumulative p24 for CT, but not for VT. To improve the ex vivo challenge assay, viruses should be evaluated for replication in mucosal tissue before study implementation, baseline mucosal tissue is not needed if a placebo/no treatment group is included within the clinical trial, and previous biopsy sites should be avoided.
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Affiliation(s)
- Charlene S. Dezzutti
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania
- Magee-Womens Research Institute, Pittsburgh, Pennsylvania
| | - Seo Young Park
- Department of Medicine Bio Statisics, and Clinical and Translational Science, University of Pittsburgh, Pittsburgh, Pennsylvania
| | | | | | - Julie R. Russo
- Magee-Womens Research Institute, Pittsburgh, Pennsylvania
| | - Ingrid Macio
- University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - Catherine A. Chappell
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania
- Magee-Womens Research Institute, Pittsburgh, Pennsylvania
| | - Katherine E. Bunge
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania
- Magee-Womens Research Institute, Pittsburgh, Pennsylvania
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Asmuth DM, Thompson CG, Chun TW, Ma ZM, Mann S, Sainz T, Serrano-Villar S, Utay NS, Garcia JC, Troia-Cancio P, Pollard RB, Miller CJ, Landay A, Kashuba AD. Tissue Pharmacologic and Virologic Determinants of Duodenal and Rectal Gastrointestinal-Associated Lymphoid Tissue Immune Reconstitution in HIV-Infected Patients Initiating Antiretroviral Therapy. J Infect Dis 2017; 216:813-818. [PMID: 28968888 PMCID: PMC6279130 DOI: 10.1093/infdis/jix418] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [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: 02/06/2017] [Accepted: 08/15/2017] [Indexed: 12/19/2022] Open
Abstract
Plasma, duodenal, and rectal tissue antiretroviral therapy (ART) drug concentrations, human immunodeficiency virus (HIV) RNA and HIV DNA copy numbers, and recovery of mucosal immunity were measured before and 9 months after initiation of 3 different ART regimens in 26 subjects. Plasma and tissue HIV RNA correlated at baseline and when 9-month declines were compared, suggesting that these compartments are tightly associated. Antiretroviral tissue:blood penetration ratios were above the 50% inhibitory concentration values in almost 100% of cases. There were no correlations between drug concentrations and HIV DNA/RNA. Importantly, no evidence was found for residual viral replication or deficient tissue drug penetration to account for delayed gastrointestinal-associated lymphoid tissue immune recovery.
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Affiliation(s)
- David M Asmuth
- University of California, Davis Medical Center, Sacramento
| | - Corbin G Thompson
- Eshelman School of Pharmacy, University of North Carolina, Chapel Hill
| | - Tae-Wook Chun
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
| | - Zhong-Min Ma
- California National Primate Research Center, Davis
| | - Surinder Mann
- University of California, Davis Medical Center, Sacramento
| | | | | | | | | | | | | | - Christopher J Miller
- University of California, Davis Medical Center, Sacramento
- California National Primate Research Center, Davis
| | - Alan Landay
- Rush University Medical Center, Chicago, Illinois
| | - Angela D Kashuba
- Eshelman School of Pharmacy, University of North Carolina, Chapel Hill
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Chiu WK, Brand RM, Camp D, Edick S, Mitchell C, Karas S, Zehmisch A, Ho K, Brand RE, Harrison J, Abo S, Cranston RD, McGowan I. The Safety of Multiple Flexible Sigmoidoscopies with Mucosal Biopsies in Healthy Clinical Trial Participants. AIDS Res Hum Retroviruses 2017; 33:820-826. [PMID: 28296471 PMCID: PMC5564058 DOI: 10.1089/aid.2016.0293] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [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] [Indexed: 12/15/2022] Open
Abstract
During Phase 1 pharmacokinetic/pharmacodynamics studies, participants may undergo multiple sigmoidoscopies, with a collection of 10-20 biopsies during each procedure. This article characterizes the safety of flexible sigmoidoscopies in clinical trial participants. We determined the number of flexible sigmoidoscopies and rectal biopsies that participants underwent and analyzed the frequency, duration, and severity of flexible sigmoidoscopy-related adverse events (AEs). During the study period, 278 participants underwent 1,004 flexible sigmoidoscopies with the collection of 15,930 rectal biopsies. The average number of procedures per participant was 3.6 (median 3; range 1-25), with an average time interval between procedures of 61.8 days (median 28 days; range 1-1,159). There were no serious AEs. Sixteen AEs were related to flexible sigmoidoscopy and occurred in 16 participants, leading to an overall 1.6% (16/1,004) AE rate per procedure and 0.1% (16/15,930) AE rate per biopsy. Of the 16 AEs, 8 (50%) involved abdominal pain, diarrhea, bleeding, flatulence, and bloating, with an average duration of 4.7 days (median 1 day; range 1-28). Most (14/16) AEs were categorized as Grade 1 (mild), whereas two of the AEs were Grade 2 (moderate). No participant withdrew due to procedure-related AEs. Overall, the number of AEs caused by flexible sigmoidoscopy with multiple biopsies was low and the severity was mild, suggesting that this procedure can be safely integrated into protocols requiring repeated intestinal mucosal sampling.
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Affiliation(s)
- Wai Kan Chiu
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Rhonda M. Brand
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
- Department of Dermatology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Danielle Camp
- Magee-Women's Research Institute, Pittsburgh, Pennsylvania
| | - Stacey Edick
- Magee-Women's Research Institute, Pittsburgh, Pennsylvania
| | - Carol Mitchell
- Magee-Women's Research Institute, Pittsburgh, Pennsylvania
| | - Sherri Karas
- Magee-Women's Research Institute, Pittsburgh, Pennsylvania
| | | | - Ken Ho
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Randall E. Brand
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Janet Harrison
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Steven Abo
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Ross D. Cranston
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Ian McGowan
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
- Magee-Women's Research Institute, Pittsburgh, Pennsylvania
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11
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Carballo-Diéguez A, Balán IC, Brown W 3rd, Giguere R, Dolezal C, Leu CS, Marzinke MA, Hendrix CW, Piper JM, Richardson BA, Grossman C, Johnson S, Gomez K, Horn S, Kunjara Na Ayudhya RP, Patterson K, Jacobson C, Bekker LG, Chariyalertsak S, Chitwarakorn A, Gonzales P, Holtz TH, Liu A, Mayer KH, Zorrilla C, Lama J, McGowan I, Cranston RD. High levels of adherence to a rectal microbicide gel and to oral Pre-Exposure Prophylaxis (PrEP) achieved in MTN-017 among men who have sex with men (MSM) and transgender women. PLoS One 2017; 12:e0181607. [PMID: 28750059 DOI: 10.1371/journal.pone.0181607] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 07/04/2017] [Indexed: 11/19/2022] Open
Abstract
Trials to assess microbicide safety require strict adherence to prescribed regimens. If adherence is suboptimal, safety cannot be adequately assessed. MTN-017 was a phase 2, randomized sequence, open-label, expanded safety and acceptability crossover study comparing 1) daily oral emtricitabine/tenofovir disoproxil fumarate (FTC/TDF), 2) daily use of reduced-glycerin 1% tenofovir (RG-TFV) gel applied rectally, and 3) RG-TFV gel applied before and after receptive anal intercourse (RAI)—if participants had no RAI in a week, they were asked to use two doses of gel within 24 hours. Product use was assessed by mixed methods including unused product return count, text messaging reports, and qualitative plasma TFV pharmacokinetic (PK) results. Convergence interviews engaged participants in determining the most accurate number of doses used based on product count and text messaging reports. Client-centered adherence counseling was also used. Participants (N = 187) were men who have sex with men and transgender women enrolled in the United States (42%), Thailand (29%), Peru (19%) and South Africa (10%). Mean age was 31.4 years (range 18–64 years). Based on convergence interviews, over an 8-week period, 94% of participants had ≥80% adherence to daily tablet, 41% having perfect adherence; 83% had ≥80% adherence to daily gel, 29% having perfect adherence; and 93% had ≥80% adherence to twice-weekly use during the RAI-associated gel regimen, 75% having perfect adherence and 77% having ≥80% adherence to gel use before and after RAI. Only 4.4% of all daily product PK results were undetectable and unexpected (TFV concentrations <0.31 ng/mL) given self-reported product use near sampling date. The mixed methods adherence measurement indicated high adherence to product use in all three regimens. Adherence to RAI-associated rectal gel use was as high as adherence to daily oral PrEP. A rectal microbicide gel, if efficacious, could be an alternative for individuals uninterested in daily oral PrEP.
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12
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Notario-Pérez F, Ruiz-Caro R, Veiga-Ochoa MD. Historical development of vaginal microbicides to prevent sexual transmission of HIV in women: from past failures to future hopes. Drug Des Devel Ther 2017; 11:1767-1787. [PMID: 28670111 PMCID: PMC5479294 DOI: 10.2147/dddt.s133170] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Infection with human immunodeficiency virus (HIV) remains a global public health concern and is particularly serious in low- and middle-income countries. Widespread sexual violence and poverty, among other factors, increase the risk of infection in women, while currently available prevention methods are outside the control of most. This has driven the study of vaginal microbicides to prevent sexual transmission of HIV from men to women in recent decades. The first microbicides evaluated were formulated as gels for daily use and contained different substances such as surfactants, acidifiers and monoclonal antibodies, which failed to demonstrate efficacy in clinical trials. A gel containing the reverse transcriptase inhibitor tenofovir showed protective efficacy in women. However, the lack of adherence by patients led to the search for dosage forms capable of releasing the active principle for longer periods, and hence to the emergence of the vaginal ring loaded with dapivirine, which requires a monthly application and is able to reduce the sexual transmission of HIV. The future of vaginal microbicides will feature the use of alternative dosage forms, nanosystems for drug release and probiotics, which have emerged as potential microbicides but are still in the early stages of development. Protecting women with vaginal microbicide formulations would, therefore, be a valuable tool for avoiding sexual transmission of HIV.
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Affiliation(s)
- Fernando Notario-Pérez
- Department of Pharmacy and Pharmaceutical Technology, School of Pharmacy, Universidad Complutense de Madrid, Madrid, Spain
| | - Roberto Ruiz-Caro
- Department of Pharmacy and Pharmaceutical Technology, School of Pharmacy, Universidad Complutense de Madrid, Madrid, Spain
| | - María-Dolores Veiga-Ochoa
- Department of Pharmacy and Pharmaceutical Technology, School of Pharmacy, Universidad Complutense de Madrid, Madrid, Spain
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Cottrell ML, Prince HM, Allmon A, Mollan KR, Hudgens MG, Sykes C, White N, Malone S, Dellon ES, Madanick RD, Shaheen NJ, Patterson KB, Kashuba AD. Cervicovaginal and Rectal Fluid as a Surrogate Marker of Antiretroviral Tissue Concentration: Implications for Clinical Trial Design. J Acquir Immune Defic Syndr 2016; 72:498-506. [PMID: 26999532 DOI: 10.1097/QAI.0000000000000996] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Quantifying tissue drug concentrations can yield important information during drug development, but complicates pharmacokinetic study design. Mucosal fluids collected by direct aspiration (cervicovaginal fluid; CVF) or swab (rectal fluid; RF) might be used as tissue concentration surrogates, but these relationships are not well characterized. METHODS Forty-nine healthy women, given a single oral dose of tenofovir, maraviroc, emtricitabine, or raltegravir at 50%-200% of the treatment dose, provided 13 plasma, 12 CVF, 12 RF and one cervical, vaginal and rectal tissue biopsy over 48 hours. Relationships between these paired samples were characterized by linear and multiple linear regression. Adjusted r values were used to select the final predictive models. RESULTS CVF exposure increased linearly with dose for all antiretrovirals (r(2) ≥ 0.23, P ≤ 0.02) except raltegravir (r(2) = 0.08, P = 0.19). In RF, only emtricitabine increased linearly with dose (r(2) = 0.27, P = 0.01). For all antiretrovirals, CVF and RF concentrations significantly correlated with mucosal tissue concentrations (female genital tract r(2) ≥ 0.37, rectal tissue (2)r ≥ 0.50, P ≤ 0.001). In the final multivariate models, plasma and fluid concentrations were both associated with FGT concentrations for all antiretrovirals (r(2) ≥ 0.81, P < 0.001). The same was noted for rectal tissue (r(2) ≥ 0.58, P < 0.001) except for tenofovir, for which RF alone was predictive of tissue concentration (r(2) = 0.91, P < 0.001). CONCLUSIONS Mucosal fluids were positively correlated with tissue concentrations and including plasma concentrations improved the regression models in most cases. Dose linearity in CVF, but not RF, suggests a saturation process in lower gastrointestinal tract tissue. These findings suggest that mucosal fluid and plasma concentrations may be used for qualitative inference of tissue concentrations for these antiretrovirals.
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14
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Cranston RD, Lama JR, Richardson BA, Carballo-Diéguez A, Kunjara Na Ayudhya RP, Liu K, Patterson KB, Leu CS, Galaska B, Jacobson CE, Parikh UM, Marzinke MA, Hendrix CW, Johnson S, Piper JM, Grossman C, Ho KS, Lucas J, Pickett J, Bekker LG, Chariyalertsak S, Chitwarakorn A, Gonzales P, Holtz TH, Liu AY, Mayer KH, Zorrilla C, Schwartz JL, Rooney J, McGowan I. MTN-017: A Rectal Phase 2 Extended Safety and Acceptability Study of Tenofovir Reduced-Glycerin 1% Gel. Clin Infect Dis 2017; 64:614-620. [PMID: 27986684 PMCID: PMC5850518 DOI: 10.1093/cid/ciw832] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [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: 09/10/2016] [Accepted: 12/06/2016] [Indexed: 11/12/2022] Open
Abstract
Background Human immunodeficiency virus (HIV) disproportionately affects men who have sex with men (MSM) and transgender women (TGW). Safe and acceptable topical HIV prevention methods that target the rectum are needed. Methods MTN-017 was a phase 2, 3-period, randomized sequence, open-label, expanded safety and acceptability crossover study comparing rectally applied reduced-glycerin (RG) 1% tenofovir (TFV) and oral emtricitabine/TFV disoproxil fumarate (FTC/TDF). In each 8-week study period participants were randomized to RG-TFV rectal gel daily, or RG-TFV rectal gel before and after receptive anal intercourse (RAI; or at least twice weekly in the event of no RAI), or daily oral FTC/TDF. Results MSM and TGW (n = 195) were enrolled from 8 sites in the United States, Thailand, Peru, and South Africa with mean age of 31.1 years (range 18-64). There were no differences in ≥grade 2 adverse event rates between daily gel (incidence rate ratio [IRR], 1.09; P = .59) or RAI gel (IRR, 0.90; P = .51) compared to FTC/TDF. High adherence (≥80% of prescribed doses assessed by unused product return and Short Message System reports) was less likely in the daily gel regimen (odds ratio [OR], 0.35; P < .001), and participants reported less likelihood of future daily gel use for HIV protection compared to FTC/TDF (OR, 0.38; P < .001). Conclusions Rectal application of RG TFV gel was safe in MSM and TGW. Adherence and product use likelihood were similar for the intermittent gel and daily oral FTC/TDF regimens, but lower for the daily gel regimen. Clinical Trials Registration NCT01687218.
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Affiliation(s)
| | - Javier R Lama
- Asociación Civil Impacta Salud y Educación, Lima, Peru
| | - Barbra A Richardson
- Department of Biostatistics, University of Washington, Box 359909, Seattle, WA, USA
- Fred Hutchinson Cancer Research Center-Statistical Center for HIV/AIDS Research and Prevention, Seattle, Washington, USA
| | | | | | - Karen Liu
- Fred Hutchinson Cancer Research Center-Statistical Center for HIV/AIDS Research and Prevention, Seattle, Washington, USA
| | - Karen B Patterson
- Fred Hutchinson Cancer Research Center-Statistical Center for HIV/AIDS Research and Prevention, Seattle, Washington, USA
| | - Cheng-Shiun Leu
- New York State Psychiatry Institute and Columbia University, New York, USA
| | - Beth Galaska
- Magee-Womens Research Institute, Pittsburgh, Pennsylvania, USA
| | | | | | - Mark A Marzinke
- Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Craig W Hendrix
- Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | | | - Jeanna M Piper
- National Institute of Allergy and Infectious Disease/DAIDS, Rockville, MD, USA
| | | | - Ken S Ho
- University of Pittsburgh, Pennsylvania, USA
| | | | | | | | - Suwat Chariyalertsak
- Research Institute for Health Sciences, Chiang Mai University, Chiang Mai, Thailand
| | - Anupong Chitwarakorn
- Thailand Ministry of Public Health-US Centers for Disease Control and Prevention Collaboration, Bangkok, Thailand
| | | | - Timothy H Holtz
- Thailand Ministry of Public Health-US Centers for Disease Control and Prevention Collaboration, Bangkok, Thailand
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Albert Y Liu
- Bridge HIV, San Francisco Department of Public Health, California, USA
| | | | - Carmen Zorrilla
- Department of Obstetrics and Gynecology, University of Puerto Rico School of Medicine, San Juan, USA
| | - Jill L Schwartz
- CONRAD/Eastern Virginia Medical School, Arlington, Virginia, USA
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15
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Abstract
Rectal enemas that contain prophylactic levels of anti-HIV microbicides such as tenofovir have emerged as a promising dosage form to prevent sexually transmitted HIV infections. The enema vehicle is promising due to its likely ability to deliver a large amount of drug along the length of the rectal canal. Computational models of microbicide drug delivery by enemas can help their design process by determining key factors governing drug transport and, more specifically, the time history and degree of protection. They can also inform interpretations of experimental pharmacokinetic measures such as drug concentrations in biopsies. The present work begins rectal microbicide PK modeling, for enema vehicles. Results here show that a paramount factor in drug transport is the time of enema retention; direct connectivity between enema fluid and the fluid within rectal crypts is also important. Computations of the percentage of stromal volume protected by a single enema dose indicate that even with only a minute of enema retention, protection of 100% can be achieved after around 14 minutes post dose. Concentrations in biopsies are dependent on biopsy thickness; and control and/or knowledge of thickness could improve accuracy and decrease variability in biopsy measurements. Results here provide evidence that enemas are a promising dosage form for rectal microbicide delivery, and offer insights into their rational design.
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Affiliation(s)
- Yajing Gao
- Department of Biomedical Engineering, Duke University, Durham, NC, United States of America
| | - David F. Katz
- Department of Biomedical Engineering, Duke University, Durham, NC, United States of America
- Department of Obstetrics and Gynecology, Duke University Medical Center, Durham, NC, United States of America
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16
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Seifert SM, Chen X, Meditz AL, Castillo-Mancilla JR, Gardner EM, Predhomme JA, Clayton C, Austin G, Palmer BE, Zheng JH, Klein B, Kerr BJ, Guida LA, Rower C, Rower JE, Kiser JJ, Bushman LR, MaWhinney S, Anderson PL. Intracellular Tenofovir and Emtricitabine Anabolites in Genital, Rectal, and Blood Compartments from First Dose to Steady State. AIDS Res Hum Retroviruses 2016; 32:981-991. [PMID: 27526873 DOI: 10.1089/aid.2016.0008] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [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: 12/29/2022] Open
Abstract
The pharmacokinetics (PK) of tenofovir-diphosphate (TFV-DP) and emtricitabine-triphosphate (FTC-TP), the active anabolites of tenofovir disoproxil fumarate (TDF), and emtricitabine (FTC) in blood, genital, and rectal compartments was determined in HIV-positive and seronegative adults who undertook a 60-day intensive PK study of daily TDF/FTC (plus efavirenz in HIV positives). Lymphocyte cell sorting, genital, and rectal sampling occurred once per subject, at staggered visits. Among 19 HIV-positive (3 female) and 21 seronegative (10 female) adults, TFV-DP in peripheral blood mononuclear cells (PBMC) accumulated 8.6-fold [95% confidence interval (CI): 7.2-10] from first-dose to steady-state concentration (Css) versus 1.7-fold (95% CI: 1.5-1.9) for FTC-TP. Css was reached in ∼11 and 3 days, respectively. Css values were similar between HIV-negative and HIV-positive individuals. Css TFV-DP in rectal mononuclear cells (1,450 fmol/106 cells, 898-2,340) was achieved in 5 days and was >10 times higher than PBMC (95 fmol/106 cells, 85-106), seminal cells (22 fmol/106 cells, 6-79), and cervical cells (111 fmol/106 cells, 64-194). FTC-TP Css was highest in PBMC (5.7 pmol/106 cells, 5.2-6.1) and cervical cells (7 pmol/106 cells, 2-19) versus rectal (0.8 pmol/106 cells, 0.6-1.1) and seminal cells (0.3 pmol/106 cells, 0.2-0.5). Genital drug concentrations on days 1-7 overlapped with estimated Css, but accumulation characteristics were based on limited data. TFV-DP and FTC-TP in cell sorted samples were highest and achieved most rapidly in CD14+ compared with CD4+, CD8+, and CD19+ cells. Together, these findings demonstrate cell-type and tissue-dependent cellular pharmacology, preferential accumulation of TFV-DP in rectal mononuclear cells, and rapid distribution into rectal and genital compartments.
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Affiliation(s)
- Sharon M. Seifert
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Xinhui Chen
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Amie L. Meditz
- Boulder Community Hospital, Beacon Center for Infectious Diseases, Boulder, Colorado
| | - Jose R. Castillo-Mancilla
- Division of Infectious Diseases, School of Medicine, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | | | - Julie A. Predhomme
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Carolyn Clayton
- Department of Biostatistics and Informatics, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Gregory Austin
- School of Medicine, Internal Medicine, Gastroenterology, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Brent E. Palmer
- Division of Allergy and Clinical Immunology, School of Medicine, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Jia-Hua Zheng
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Brandon Klein
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Becky J. Kerr
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - L. Anthony Guida
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Caitlin Rower
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Joseph E. Rower
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Jennifer J. Kiser
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Lane R. Bushman
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Samantha MaWhinney
- Department of Biostatistics and Informatics, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Peter L. Anderson
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
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Hendrix C. When is a PrEP candidate ready for phase 3? Lancet HIV 2016; 3:e551-e553. [PMID: 27658865 DOI: 10.1016/s2352-3018(16)30162-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 09/05/2016] [Indexed: 11/26/2022]
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18
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Vargas G, Vincent KL, Zhu Y, Szafron D, Brown TC, Villarreal PP, Bourne N, Milligan GN, Motamedi M. In Vivo Rectal Mucosal Barrier Function Imaging in a Large-Animal Model by Using Confocal Endomicroscopy: Implications for Injury Assessment and Use in HIV Prevention Studies. Antimicrob Agents Chemother 2016; 60:4600-9. [PMID: 27185807 DOI: 10.1128/AAC.00134-16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Accepted: 05/09/2016] [Indexed: 12/16/2022] Open
Abstract
Injury occurring on the surface of the rectal mucosal lining that causes defects in barrier function may result in increased risk for transmission of infection by HIV and other pathogens. Such injury could occur from microbicidal or other topical agents, mechanical trauma during consensual or nonconsensual intercourse, or inflammatory conditions. Tools for evaluation of rectal mucosal barrier function for assessing the mucosa under these conditions are lacking, particularly those that can provide in vivo structural and functional barrier integrity assessment and are adaptable to longitudinal imaging. We investigated confocal endomicroscopy (CE) as a means for in vivo imaging of the rectal epithelial barrier in the ovine model following spatially confined injury to the surface at a controlled site using a topical application of the microbicide test agent benzalkonium chloride. Topical and intravenous (i.v.) fluorescent probes were used with CE to provide subcellular resolution imaging of the mucosal surface and assessment of barrier function loss. A 3-point CE grading system based on cellular structure integrity and leakage of dye through the mucosa showed significant differences in score between untreated (1.19 ± 0.53) and treated (2.55 ± 0.75) tissue (P < 0.0001). Histological grading confirmed findings of barrier compromise. The results indicate that CE is an effective means for detecting epithelial injury and barrier loss following localized trauma in a large-animal model. CE is promising for real-time rectal mucosal evaluation after injury or trauma or topical application of emerging biomedical prevention strategies designed to combat HIV.
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19
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Cottrell ML, Yang KH, Prince HMA, Sykes C, White N, Malone S, Dellon ES, Madanick RD, Shaheen NJ, Hudgens MG, Wulff J, Patterson KB, Nelson JAE, Kashuba ADM. A Translational Pharmacology Approach to Predicting Outcomes of Preexposure Prophylaxis Against HIV in Men and Women Using Tenofovir Disoproxil Fumarate With or Without Emtricitabine. J Infect Dis 2016; 214:55-64. [PMID: 26917574 PMCID: PMC4907409 DOI: 10.1093/infdis/jiw077] [Citation(s) in RCA: 229] [Impact Index Per Article: 28.6] [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: 10/28/2015] [Accepted: 02/19/2016] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND A novel translational pharmacology investigation was conducted by combining an in vitro efficacy target with mucosal tissue pharmacokinetic (PK) data and mathematical modeling to determine the number of doses required for effective human immunodeficiency virus (HIV) preexposure prophylaxis (PrEP). METHODS A PK/pharmacodynamic (PD) model was developed by measuring mucosal tissue concentrations of tenofovir, emtricitabine, their active metabolites (tenofovir diphosphate [TFVdp] and emtricitabine triphosphate [FTCtp], respectively), and competing endogenous nucleotides (dATP and dCTP) in 47 healthy women. TZM-bl and CD4(+) T cells were used to identify 90% effective concentration (EC90) ratios of TFVdp to dATP and FTCtp to dCTP (alone and in combination) for protection against HIV. Monte-Carlo simulations were then performed to identify minimally effective dosing strategies to protect lower female genital tract and colorectal tissues. RESULTS The colorectal TFVdp concentration was 10 times higher than that in the lower female genital tract, whereas concentrations of endogenous nucleotides were 7-11 times lower. Our model predicted that ≥98% of the population achieved protective mucosal tissue exposure by the third daily dose of tenofovir disoproxil fumarate plus emtricitabine. However, a minimum adherence to 6 of 7 doses/week (85%) was required to protect lower female genital tract tissue from HIV, while adherence to 2 of 7 doses/week (28%) was required to protect colorectal tissue. CONCLUSIONS This model is predictive of recent PrEP trial results in which 2-3 doses/week was 75%-90% effective in men but ineffective in women. These data provide a novel approach for future PrEP investigations that can optimize clinical trial dosing strategies.
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Affiliation(s)
- Mackenzie L Cottrell
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina-Chapel Hill
| | - Kuo H Yang
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, employee at the time the work was done
| | | | - Craig Sykes
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina-Chapel Hill
| | - Nicole White
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina-Chapel Hill
| | - Stephanie Malone
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina-Chapel Hill
| | | | | | | | | | | | | | - Julie A E Nelson
- Virology, Immunology, and Microbiology Core, UNC Center for AIDS Research, University of North Carolina-Chapel Hill
| | - Angela D M Kashuba
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina-Chapel Hill
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20
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Ren Y, Li L, Wan Y, Wang W, Wang J, Chen J, Wei Q, Qin C, Xu J, Zhang X. Mucosal Topical Microbicide Candidates Exert Influence on the Subsequent SIV Infection and Survival by Regulating SIV-Specific T-Cell Immune Responses. J Acquir Immune Defic Syndr 2016; 71:121-9. [PMID: 26413849 DOI: 10.1097/QAI.0000000000000851] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
OBJECTIVE To determine whether mucosal topical microbicides have any influence on disease progression during subsequent simian immunodeficiency virus (SIV) infection. DESIGN A 2-phase study was performed in primate monkeys. The first phase mimicked microbicide efficacy studies; the second phase served to determine the disease progression in a productive infection model. METHODS During the first phase, monkeys were intrarectally pretreated with tenofovir, sifuvirtide (SFT), or maraviroc-formulated microbicides and then challenged with low-dose SHIV-1157ipd3N4. Second, all monkeys were rechallenged with a single high dose of SIVmac239 to generate productive infections. The survival rate, viral loads, CD4(+) T-cell counts, and SIV-specific T-cell responses were determined during the 104-week following up. RESULTS Repeated rectal challenges did not result in productive infection in all groups, evidenced by undetectable viral loads with occasional viral blips during the first phase of this study. All monkeys were productively infected after the high-dose rechallenge with SIVmac239. Two groups, including maraviroc-treated and tenofovir-treated groups, experienced 100% mortality during the 104-week following up. In contrast, the SFT-treated group showed significantly higher survival, and only 25% died at week 95. Interestingly, SIV-specific T-cell responses were also significantly higher in the SFT group. Transcriptomic analyses evidenced immune imprint in immune system among different microbicide-treated groups. CONCLUSIONS This study provides preliminary but important evidence for the influence of prophylactically applied microbicides on disease progression of subsequent SIV infection and suggests that the long-term immune safety concern for microbicides should be also considered in the effort to develop effective microbicides.
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21
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Thurman AR, Chandra N, Yousefieh N, Zalenskaya I, Kimble T, Asin S, Rollenhagen C, Anderson SM, Herold B, Mesquita PM, Richardson-Harman N, Cunningham T, Schwartz JL, Doncel GF. Comparison of Follicular and Luteal Phase Mucosal Markers of HIV Susceptibility in Healthy Women. AIDS Res Hum Retroviruses 2016; 32:547-60. [PMID: 26750085 DOI: 10.1089/aid.2015.0264] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The purpose of this study was to evaluate differences in vaginal immune cell populations, vaginal tissue gene expression, antimicrobial activity of the cervicovaginal (CV) lavage (CVL), vaginal flora, and p24 antigen production from CV tissues after ex vivo human immunodeficiency virus (HIV) infection between follicular (FOL) and luteal (LUT) phases of the menstrual cycle. CV tissue biopsies, CV secretions, and blood samples were obtained as part of two longitudinal clinical trials of healthy women (CONRAD D11-119 and A12-124 studies). Participants (n = 39) were HIV-seronegative women not using exogenous hormone supplementation, with normal menstrual cycles, who were screened to exclude sexually transmitted and reproductive tract infections. Serum levels of estradiol and progesterone were significantly higher in the LUT versus the FOL phase of the menstrual cycle. Controlling for race, reported contraceptive use/sexual practices, and clinical trial, we found no differences in vaginal tissue immune cell populations and activation status, transcriptomes, inhibition of HIV, herpes simplex virus type 2 and Escherichia coli by the CVL, vaginal pH or Nugent score, or production of p24 antigen after ex vivo infection by HIV-1BaL between CV samples obtained in the FOL phase versus the LUT phase of the menstrual cycle. There were no significant correlations between serum estradiol and progesterone levels and CV endpoints. The hypothesis that the LUT phase of the menstrual cycle represents a more vulnerable stage for mucosal infection with HIV was not supported by data from samples obtained from the lower genital tract (ectocervix and vagina) from these two clinical trials.
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Affiliation(s)
| | | | | | | | - Thomas Kimble
- CONRAD, Eastern Virginia Medical School, Norfolk, Virginia
| | - Susana Asin
- V.A. Medical Center, White River Junction VT and Geisel School of Medicine at Dartmouth, Dartmouth, New Hampshire
| | - Christiane Rollenhagen
- V.A. Medical Center, White River Junction VT and Geisel School of Medicine at Dartmouth, Dartmouth, New Hampshire
| | | | - Betsy Herold
- Albert Einstein College of Medicine, Bronx, New York
| | | | | | - Tina Cunningham
- School of Public Health, Eastern Virginia Medical School, Norfolk, Virginia
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22
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Leyva F, Fuchs EJ, Bakshi R, Carballo-Dieguez A, Ventuneac A, Yue C, Caffo B, Du Y, Torbenson M, Li L, Mullin G, Lee L, Rohan L, Anton PA, Hendrix CW. Simultaneous Evaluation of Safety, Acceptability, Pericoital Kinetics, and Ex Vivo Pharmacodynamics Comparing Four Rectal Microbicide Vehicle Candidates. AIDS Res Hum Retroviruses 2015; 31:1089-97. [PMID: 26066390 DOI: 10.1089/aid.2015.0086] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Preexposure prophylaxis (PrEP) of HIV infection with tenofovir-containing regimens is effective, but plagued by poor adherence in some studies. Options for safe, effective, and acceptable PrEP products, especially for men and women at risk of HIV via receptive anal intercourse (RAI), are needed. We performed a randomized, partially blinded, first-in-human evaluation of four candidate rectal microbicide vehicles-aqueous gel, aqueous fluid, lipid gel, and lipid fluid-to select a prototype for further clinical development. Eight seronegative participants received three doses of each product with each dose separated by at least 2 weeks: one dose was given alone without simulated RAI in clinic, another dose was followed by simulated RAI in clinic, and another dose was self-administered at home in the context of RAI with a partner. Assessments included safety, acceptability, colon histology, ex vivo HIV infectivity of colon tissue explants, and colonic luminal distribution of vehicle and HIV surrogates. Adverse events were all mild and mainly sigmoidoscopy associated. There were minor differences in colon distribution of products and little effect of RAI. Vehicle distribution covered 95% (±7% standard deviation) of the distribution of an HIV surrogate in the colonic lumen. The lipid fluid vehicle increased HIV colon tissue infectability 5-fold [log10 p24 0.68 (95% confidence interval 0.08, 1.28)] and aqueous gel provided 6-fold protection [log10 p24 0.80 (95% confidence interval 0.20, 1.41)] compared to no product baseline. Colon permeability of lipid vehicles was more than 10-fold greater than aqueous vehicles. All products received similar acceptability ratings, though trends favored the gel products. Intensive simultaneous assessment of safety and toxicity, luminal and tissue distribution, ex vivo HIV infectivity, and product acceptability in relevant sexual contexts provided clear differentiation among candidate gels very early in product development. We selected the aqueous gel for further development as a rectal microbicide vehicle.
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Affiliation(s)
- Francisco Leyva
- Department of Medicine (Clinical Pharmacology), The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Edward J. Fuchs
- Department of Medicine (Clinical Pharmacology), The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Rahul Bakshi
- Department of Medicine (Clinical Pharmacology), The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Alex Carballo-Dieguez
- Department of Medicine (Gastroenterology), The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Ana Ventuneac
- Department of Medicine (Gastroenterology), The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Chen Yue
- Department of Biostatistics, The Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland
| | - Brian Caffo
- Department of Biostatistics, The Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland
| | - Yong Du
- Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | | | - Liye Li
- Department of Medicine (Clinical Pharmacology), The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Gerald Mullin
- HIV Center for Clinical and Behavioral Studies, Columbia University, New York, New York
| | - Linda Lee
- HIV Center for Clinical and Behavioral Studies, Columbia University, New York, New York
| | - Lisa Rohan
- Magee Womens Research Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Peter A. Anton
- UCLA Center for HIV Prevention Research, UCLA AIDS Institute, Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Craig W. Hendrix
- Department of Medicine (Clinical Pharmacology), The Johns Hopkins University School of Medicine, Baltimore, Maryland
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Dobard CW, Taylor A, Sharma S, Anderson PL, Bushman LR, Chuong D, Pau CP, Hanson D, Wang L, Garcia-Lerma JG, McGowan I, Rohan L, Heneine W. Protection Against Rectal Chimeric Simian/Human Immunodeficiency Virus Transmission in Macaques by Rectal-Specific Gel Formulations of Maraviroc and Tenofovir. J Infect Dis 2015; 212:1988-95. [PMID: 26071566 DOI: 10.1093/infdis/jiv334] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Accepted: 05/29/2015] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Rectal human immunodeficiency virus (HIV) transmission is an important driver of the HIV epidemic. Optimally formulated gels of antiretroviral drugs are under development for preventing rectally acquired HIV. We investigated in a macaque model the pharmacokinetics and efficacy of 3 rectal gel formulations METHODS Single-dose pharmacokinetics of low-osmolar 1% maraviroc (MVC), 1% tenofovir (TFV), or 1% MVC/1% TFV combination gel were evaluated in blood, rectal fluids, colorectal biopsy specimens, and rectal lymphocytes. Efficacy was evaluated over 10 twice-weekly rectal SHIV162p3 challenges in rhesus macaques that received either placebo (n = 7), MVC (n = 6), TFV (n = 6), or MVC/TFV (n = 6) gel 30 minutes before each challenge. RESULTS MVC and TFV were detected in plasma 30 minutes after gel application and remained above 95% inhibitory concentrations in rectal fluids at 24 hours. MVC, TFV, and TFV diphosphate (TFV-DP) concentrations in colorectal tissues collected up to 30 cm from the anal margin were all high at 2 hours, demonstrating rapid and extended tissue dosing. TFV-DP concentrations in tissue homogenates and rectal lymphocytes were highly correlated (r(2) = 0.82). All 3 gel formulations were highly protective (82% efficacy; P ≤ .02 by the log-rank test). CONCLUSIONS Desirable pharmacokinetic profiles and high efficacy in this macaque model support the clinical development of these gel formulations for preventing rectal HIV infection.
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Affiliation(s)
- Charles W Dobard
- Laboratory Branch, Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia
| | | | - Sunita Sharma
- Laboratory Branch, Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Peter L Anderson
- Department of Pharmaceutical Sciences, University of Colorado School of Pharmacy, Aurora
| | - Lane R Bushman
- Department of Pharmaceutical Sciences, University of Colorado School of Pharmacy, Aurora
| | - Dinh Chuong
- Laboratory Branch, Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Chou-Pong Pau
- Laboratory Branch, Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Debra Hanson
- Laboratory Branch, Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Lin Wang
- Magee Women's Research Institute, University of Pittsburgh, Pennsylvania
| | - J Gerardo Garcia-Lerma
- Laboratory Branch, Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Ian McGowan
- Magee Women's Research Institute, University of Pittsburgh, Pennsylvania
| | - Lisa Rohan
- Magee Women's Research Institute, University of Pittsburgh, Pennsylvania
| | - Walid Heneine
- Laboratory Branch, Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia
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Abstract
INTRODUCTION In the absence of an HIV vaccine or cure, antiretroviral (ARV)-based prevention strategies are being investigated to reduce HIV incidence. These prevention strategies depend on achieving effective drug concentrations at the site of HIV exposure, which is most commonly the mucosal tissue of the lower gastrointestinal tract and the female genital tract. AREAS COVERED This article collates all known data regarding drug exposure in these vulnerable mucosal tissues and reviews important mechanisms of ARV drug distribution. Research papers and abstracts describing ARV pharmacokinetics (PK) in the female genital tract and lower gastrointestinal mucosal tissues available in MEDLINE® or presented at scientific conferences prior to December 2014 are reviewed in detail. Important influences on ARV mucosal tissue distribution, including protein binding, active drug transport and endogenous hormones are also reviewed. EXPERT OPINION ARVs exhibit highly variable PK in mucosal tissues. In general, ARV exposure is higher in the lower gastrointestinal tract compared with the female genital tract, but concentrations required for protective efficacy are largely unknown. The expected site of HIV exposure represents an important consideration when designing and optimizing ARV-based prevention strategies.
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Affiliation(s)
- Mackenzie L Cottrell
- University of North Carolina, UNC Eshelman School of Pharmacy, Division of Pharmacotherapy and Experimental Therapeutics , 1094 Genetic Medicine Building, CB# 7361, 120 Mason Farm Road, Chapel Hill, NC 27599 , USA +1 919 966 9998 ; +1 919 962 0644 ;
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Richardson-Harman N, Hendrix CW, Bumpus NN, Mauck C, Cranston RD, Yang K, Elliott J, Tanner K, McGowan I, Kashuba A, Anton PA. Correlation between compartmental tenofovir concentrations and an ex vivo rectal biopsy model of tissue infectibility in the RMP-02/MTN-006 phase 1 study. PLoS One 2014; 9:e111507. [PMID: 25350130 PMCID: PMC4211741 DOI: 10.1371/journal.pone.0111507] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [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: 01/17/2014] [Accepted: 09/30/2014] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVES This study was designed to assess the dose-response relationship between tissue, blood, vaginal and rectal compartment concentrations of tenofovir (TFV) and tenofovir diphosphate (TFVdp) and ex vivo rectal HIV suppression following oral tenofovir disoproxil fumarate (TDF) and rectal administration of TFV 1% vaginally-formulated gel. DESIGN Phase 1, randomized, two-site (US), double-blind, placebo-controlled study of sexually-abstinent males and females. METHODS Eighteen participants received a single 300 mg exposure of oral TDF and were then randomized 2∶1 to receive a single then seven-daily rectal exposures of TFV 1% gel (40 mg TFV per 4 ml gel application) or hydroxyethyl-cellulose (HEC) placebo gel. Blood and rectal biopsies were collected for pharmacokinetic TDF and TFVdp analyses and ex vivo HIV-1 challenge. RESULTS There was a significant fit for the TFVdp dose-response model for rectal tissue (p = 0.0004), CD4+MMC (p<0.0001), CD4-MMC (p<0.0001), and TotalMMC (p<0.0001) compartments with r2 ranging 0.36-0.64. Higher concentrations of TFVdp corresponded with lower p24, consistent with drug-mediated virus suppression. The single oral treatment failed to provide adequate compartment drug exposure to reach the EC50 of rectal tissue TFVdp predicted to be necessary to suppress HIV in rectal tissue. The EC50 for CD4+MMC was within the single topical treatment range, providing evidence that a 1% topical, vaginally-formulated TFV gel provided in-vivo doses predicted to provide for 50% efficacy in the ex vivo assay. The 7-daily topical TFV gel treatment provided TFVdp concentrations that reached EC90 biopsy efficacy for CD4-MMC, CD4+MMC and TotalMMC compartments. CONCLUSION The TFVdp MMC compartment (CD4+, CD4- and Total) provided the best surrogate for biopsy infectibility and the 7-daily topical TFV gel treatment provided the strongest PK profile for HIV suppression. ClinicalTrials.gov NCT00984971.
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Affiliation(s)
| | - Craig W. Hendrix
- Departments of Medicine and Pharmacology, Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Namandjé N. Bumpus
- Departments of Medicine and Pharmacology, Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | | | - Ross D. Cranston
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Kuo Yang
- Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States of America
| | - Julie Elliott
- Center for HIV Prevention Research, UCLA AIDS Institute, Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States of America
| | - Karen Tanner
- Center for HIV Prevention Research, UCLA AIDS Institute, Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States of America
| | - Ian McGowan
- Magee-Womens Research Institute, University of Pittsburgh Medical School, Pittsburgh, PA, United States of America
| | - Angela Kashuba
- Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States of America
| | - Peter A. Anton
- Center for HIV Prevention Research, UCLA AIDS Institute, Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States of America
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