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Dedeloudi A, Siamidi A, Pavlou P, Vlachou M. Recent Advances in the Excipients Used in Modified Release Vaginal Formulations. MATERIALS 2022; 15:ma15010327. [PMID: 35009472 PMCID: PMC8745980 DOI: 10.3390/ma15010327] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 12/29/2021] [Accepted: 12/30/2021] [Indexed: 12/10/2022]
Abstract
The formulation of an ideal vaginal drug delivery system (DDS), with the requisite properties, with respect to safety, efficacy, patient compliance, aesthetics, harmonization with the regulatory requirements, and cost, requires a meticulous selection of the active ingredients and the excipients used. Novel excipients defined by diversity and multifunctionality are used in order to ameliorate drug delivery attributes. Synthetic and natural polymers are broadly used in pharmaceutical vaginal formulations (solid, semi-solid dosage forms, implantable devices, and nanomedicines) with a promising perspective in improving stability and compatibility issues when administered topically or systemically. Moreover, the use of biopolymers is aiming towards formulating novel bioactive, biocompatible, and biodegradable DDSs with a controllable drug release rate. Overviewing vaginal microenvironment, which is described by variable and perplexed features, a perceptive choice of excipients is essential. This review summarizes the recent advances on the excipients used in modified vaginal drug delivery formulations, in an attempt to aid the formulation scientist in selecting the optimal excipients for the preparation of vaginal products.
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Affiliation(s)
- Aikaterini Dedeloudi
- Department of Pharmacy, Division of Pharmaceutical Technology, School of Health Sciences, National and Kapodistrian University of Athens, 15784 Athens, Greece; (A.D.); (A.S.)
| | - Angeliki Siamidi
- Department of Pharmacy, Division of Pharmaceutical Technology, School of Health Sciences, National and Kapodistrian University of Athens, 15784 Athens, Greece; (A.D.); (A.S.)
| | - Panagoula Pavlou
- Laboratory of Chemistry-Biochemistry-Cosmetic Science, Department of Biomedical Sciences, University of West Attica, 28 Ag. Spyridonos Str., 12243 Egaleo, Greece;
| | - Marilena Vlachou
- Department of Pharmacy, Division of Pharmaceutical Technology, School of Health Sciences, National and Kapodistrian University of Athens, 15784 Athens, Greece; (A.D.); (A.S.)
- Correspondence: ; Tel.: +30-2107274674
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Girard L, Birse K, Holm JB, Gajer P, Humphrys MS, Garber D, Guenthner P, Noël-Romas L, Abou M, McCorrister S, Westmacott G, Wang L, Rohan LC, Matoba N, McNicholl J, Palmer KE, Ravel J, Burgener AD. Impact of the griffithsin anti-HIV microbicide and placebo gels on the rectal mucosal proteome and microbiome in non-human primates. Sci Rep 2018; 8:8059. [PMID: 29795295 PMCID: PMC5966460 DOI: 10.1038/s41598-018-26313-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 05/10/2018] [Indexed: 12/26/2022] Open
Abstract
Topical microbicides are being explored as an HIV prevention method for individuals who practice receptive anal intercourse. In vivo studies of these microbicides are critical to confirm safety. Here, we evaluated the impact of a rectal microbicide containing the antiviral lectin, Griffithsin (GRFT), on the rectal mucosal proteome and microbiome. Using a randomized, crossover placebo-controlled design, six rhesus macaques received applications of hydroxyethylcellulose (HEC)- or carbopol-formulated 0.1% GRFT gels. Rectal mucosal samples were then evaluated by label-free tandem MS/MS and 16 S rRNA gene amplicon sequencing, for proteomics and microbiome analyses, respectively. Compared to placebo, GRFT gels were not associated with any significant changes to protein levels at any time point (FDR < 5%), but increased abundances of two common and beneficial microbial taxa after 24 hours were observed in HEC-GRFT gel (p < 2E-09). Compared to baseline, both placebo formulations were associated with alterations to proteins involved in proteolysis, activation of the immune response and inflammation after 2 hours (p < 0.0001), and increases in beneficial Faecalibacterium spp. after 24 hours in HEC placebo gel (p = 4.21E-15). This study supports the safety profile of 0.1% GRFT gel as an anti-HIV microbicide and demonstrates that current placebo formulations may associate with changes to rectal proteome and microbiota.
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Affiliation(s)
- Lauren Girard
- National HIV and Retrovirology Labs, JC Wilt Infectious Diseases Research Centre, Public Health Agency of Canada, Winnipeg, Canada
- Department of Medical Microbiology, University of Manitoba, Winnipeg, Canada
| | - Kenzie Birse
- National HIV and Retrovirology Labs, JC Wilt Infectious Diseases Research Centre, Public Health Agency of Canada, Winnipeg, Canada
- Department of Medical Microbiology, University of Manitoba, Winnipeg, Canada
| | - Johanna B Holm
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, USA
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, USA
| | - Pawel Gajer
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, USA
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, USA
| | - Mike S Humphrys
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, USA
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, USA
| | - David Garber
- Laboratory Branch, Division of HIV/AIDS Prevention, National Centre for HIV/AIDS, Viral Hepatitis, Sexually Transmitted Disease and Tuberculosis Prevention, CDC, Atlanta, USA
| | - Patricia Guenthner
- Laboratory Branch, Division of HIV/AIDS Prevention, National Centre for HIV/AIDS, Viral Hepatitis, Sexually Transmitted Disease and Tuberculosis Prevention, CDC, Atlanta, USA
| | - Laura Noël-Romas
- National HIV and Retrovirology Labs, JC Wilt Infectious Diseases Research Centre, Public Health Agency of Canada, Winnipeg, Canada
- Department of Medical Microbiology, University of Manitoba, Winnipeg, Canada
| | - Max Abou
- National HIV and Retrovirology Labs, JC Wilt Infectious Diseases Research Centre, Public Health Agency of Canada, Winnipeg, Canada
| | - Stuart McCorrister
- Mass Spectrometry and Proteomics Core Facility, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada
| | - Garrett Westmacott
- Mass Spectrometry and Proteomics Core Facility, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada
| | - Lin Wang
- Magee Women's Research Institute, Pittsburgh, USA
- School of Pharmacy, University of Pittsburgh, Pittsburgh, USA
| | - Lisa C Rohan
- Magee Women's Research Institute, Pittsburgh, USA
- School of Pharmacy, University of Pittsburgh, Pittsburgh, USA
| | - Nobuyuki Matoba
- Center for Predictive Medicine, University of Louisville, Louisville, USA
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, USA
- James Graham Brown Cancer Centre, University of Louisville, Louisville, USA
| | - Janet McNicholl
- Laboratory Branch, Division of HIV/AIDS Prevention, National Centre for HIV/AIDS, Viral Hepatitis, Sexually Transmitted Disease and Tuberculosis Prevention, CDC, Atlanta, USA
| | - Kenneth E Palmer
- Center for Predictive Medicine, University of Louisville, Louisville, USA
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, USA
- James Graham Brown Cancer Centre, University of Louisville, Louisville, USA
| | - Jacques Ravel
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, USA
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, USA
| | - Adam D Burgener
- National HIV and Retrovirology Labs, JC Wilt Infectious Diseases Research Centre, Public Health Agency of Canada, Winnipeg, Canada.
- Department of Medical Microbiology, University of Manitoba, Winnipeg, Canada.
- Unit of Infectious Diseases, Department of Medicine Solna, Centre for Molecular Medicine, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden.
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Alexandre KB, Mufhandu HT, London GM, Chakauya E, Khati M. Progress and Perspectives on HIV-1 microbicide development. Virology 2016; 497:69-80. [PMID: 27429040 DOI: 10.1016/j.virol.2016.07.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Revised: 07/01/2016] [Accepted: 07/04/2016] [Indexed: 12/12/2022]
Abstract
The majority of HIV-1 infections occur via sexual intercourse. Women are the most affected by the epidemic, particularly in developing countries, due to their socio-economic dependence on men and the fact that they are often victims of gender based sexual violence. Despite significant efforts that resulted in the reduction of infection rates in some countries, there is still need for effective prevention methods against the virus. One of these methods for preventing sexual transmission in women is the use of microbicides. In this review we provide a summary of the progress made toward the discovery of affordable and effective HIV-1 microbicides and suggest future directions. We show that there is a wide range of compounds that have been proposed as potential microbicides. Although most of them have so far failed to show protection in humans, there are many promising ones currently in pre-clinical studies and in clinical trials.
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Affiliation(s)
- Kabamba B Alexandre
- Council for Scientific and Industrial Research, Pioneering Health Sciences Laboratory, Biosciences Unit, Pretoria, Gauteng, South Africa.
| | - Hazel T Mufhandu
- Council for Scientific and Industrial Research, Pioneering Health Sciences Laboratory, Biosciences Unit, Pretoria, Gauteng, South Africa
| | - Grace M London
- Department of Health Free State District Health Services and Health Programs, South Africa
| | - E Chakauya
- Council for Scientific and Industrial Research, Pioneering Health Sciences Laboratory, Biosciences Unit, Pretoria, Gauteng, South Africa
| | - M Khati
- Council for Scientific and Industrial Research, Pioneering Health Sciences Laboratory, Biosciences Unit, Pretoria, Gauteng, South Africa; University of Cape Town and Groote Schuur Hospital, Department of Medicine, Cape Town, South Africa
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Antimisiaris SG, Mourtas S. Recent advances on anti-HIV vaginal delivery systems development. Adv Drug Deliv Rev 2015; 92:123-45. [PMID: 25858666 DOI: 10.1016/j.addr.2015.03.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2014] [Revised: 03/04/2015] [Accepted: 03/27/2015] [Indexed: 10/23/2022]
Abstract
A review of the recent outcomes regarding technologies to prevent vaginal transmission of HIV, mainly by using antiretroviral (ARV) drugs formulated as microbicides. An introduction about the HIV transmission mechanisms by the vaginal route is included, together with the recent challenges faced for development of successful microbicide products. The outcomes of clinical evaluations are mentioned, and the different formulation strategies studied to-date, with the requirements, advantages, disadvantages and limitations of each dosage-form type, are presented. Finally, the recent attempts to apply various types of nanotechnologies in order to develop advanced microbicide-products and overcome existing limitations, are discussed.
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Sepúlveda-Crespo D, Sánchez-Rodríguez J, Serramía MJ, Gómez R, De La Mata FJ, Jiménez JL, Muñoz-Fernández MÁ. Triple combination of carbosilane dendrimers, tenofovir and maraviroc as potential microbicide to prevent HIV-1 sexual transmission. Nanomedicine (Lond) 2015; 10:899-914. [PMID: 25867856 DOI: 10.2217/nnm.14.79] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
AIM To research the synergistic activity by triple combinations of carbosilane dendrimers with tenofovir and maraviroc as topical microbicide. METHODS Cytotoxicity, anti-HIV-1 activity, vaginal irritation and histological analysis of triple combinations were determined. Analysis of combined effects and the median effective concentration were performed using CalcuSyn software. RESULTS Combinations showed a greater broad-spectrum anti-HIV-1 activity than the single-drug, and preserved this activity in acid environment or seminal fluid. The strongest combinations were G2-STE16/G2-S24P/tenofovir, G2-STE16/G2-S16/maraviroc and G2-STE16/tenofovir/maraviroc at 2:2:1, 10:10:1 10:5:1 ratios, respectively. They demonstrated strong synergistic activity profile due to the weighted average combination indices varied between 0.06 and 0.38. No irritation was detected in female BALB/c mice. CONCLUSION The three-drug combination increases their antiviral potency and act synergistically as potential microbicide.
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Affiliation(s)
- Daniel Sepúlveda-Crespo
- Laboratorio InmunoBiología Molecular, Hospital General Universitario Gregorio Marañón, Instituto de Investigación Sanitaria Gregorio Marañón, Spanish HIV-HGM Biobank, Networking Research Center on Bioengineering, Biomaterials & Nanomedicine (CIBER-BBN), Madrid, Spain
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Kramzer LF, Cohen J, Schubert J, Dezzutti CS, Moncla BJ, Friend D, Rohan LC. Assessing the potential of the Woman's Condom for vaginal drug delivery. Contraception 2015; 92:254-60. [PMID: 25998936 DOI: 10.1016/j.contraception.2015.05.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2014] [Revised: 04/02/2015] [Accepted: 05/09/2015] [Indexed: 10/23/2022]
Abstract
BACKGROUND The Woman's Condom is a new female condom that uses a dissolvable polyvinyl alcohol capsule to simplify vaginal insertion. This preclinical study assessed the feasibility to incorporate an antiviral drug, UC781, into the Woman's Condom capsule, offering a unique drug delivery platform. STUDY DESIGN UC781 capsules were fabricated using methods from the development of the Woman's Condom capsules as well as those used in vaginal film development. Capsules were characterized to evaluate physical/chemical attributes, Lactobacillus compatibility, in vitro safety and bioactivity, and condom compatibility. RESULTS Two UC781 capsule platforms were assessed. Capsule masses (mg; mean±SD) for platforms 1 and 2 were 116.50±18.22 and 93.80±8.49, respectively. Thicknesses were 0.0034±0.0004 in and 0.0033±0.0004 in. Disintegration times were 11±3 s and 5±1 s. Puncture strengths were 21.72±3.30 N and 4.02±0.83 N. Water content measured 6.98±1.17% and 7.04±1.92%. UC781 content was 0.59±0.05 mg and 0.77±0.11 mg. Both platforms retained in vitro bioactivity and were nontoxic to TZM-bl cells and Lactobacillus. Short-term storage of UC781 capsules with the Woman's Condom pouch did not decrease condom mechanical integrity. CONCLUSIONS UC781 was loaded into a polymeric capsule similar to that of the Woman's Condom product. This study highlights the potential use of the Woman's Condom as a platform for vaginal delivery of drugs relevant to sexual/reproductive health, including those for short- or long-acting HIV prevention. IMPLICATIONS We determined the proof-of-concept feasibility of incorporation of an HIV-preventative microbicide into the Woman's Condom capsule. This study highlights various in vitro physical and chemical evaluations as well as bioactivity and safety assessments necessary for vaginal product development related to female sexual and reproductive health.
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Affiliation(s)
- Lindsay F Kramzer
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, 3501 Terrace Street, Pittsburgh, PA, 15261, USA; Magee-Womens Research Institute, 204 Craft Avenue, Pittsburgh, PA, 15213, USA
| | - Jessica Cohen
- PATH, 2201 Westlake Avenue Suite 200, Seattle, WA, 98121, USA
| | - Jesse Schubert
- PATH, 2201 Westlake Avenue Suite 200, Seattle, WA, 98121, USA
| | - Charlene S Dezzutti
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine, University of Pittsburgh, M240 Scaife Hall, 3550 Terrace Street, Pittsburgh, PA, 15261, USA; Magee-Womens Research Institute, 204 Craft Avenue, Pittsburgh, PA, 15213, USA
| | - Bernard J Moncla
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine, University of Pittsburgh, M240 Scaife Hall, 3550 Terrace Street, Pittsburgh, PA, 15261, USA; Magee-Womens Research Institute, 204 Craft Avenue, Pittsburgh, PA, 15213, USA
| | - David Friend
- CONRAD, 1911 North Fort Myer Drive Suite 900, Arlington, VA, 22209, USA
| | - Lisa C Rohan
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, 3501 Terrace Street, Pittsburgh, PA, 15261, USA; Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine, University of Pittsburgh, M240 Scaife Hall, 3550 Terrace Street, Pittsburgh, PA, 15261, USA; Magee-Womens Research Institute, 204 Craft Avenue, Pittsburgh, PA, 15213, USA.
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7
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Clark MR, Kiser PF, Loxley A, McConville C, Malcolm RK, Friend DR. Pharmacokinetics of UC781-loaded intravaginal ring segments in rabbits: a comparison of polymer matrices. Drug Deliv Transl Res 2015; 1:238-46. [PMID: 25788242 DOI: 10.1007/s13346-011-0032-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
UC781 is a potent and poorly water-soluble nonnucleoside reverse transcriptase inhibitor being investigated as a potential microbicide for preventing sexual transmission of HIV-1. This study was designed to evaluate the in vivo release and pharmacokinetics of UC781 delivered from matrix-type intravaginal ring segments in rabbits. Three polymer matrices (polyurethane, ethylene vinyl acetate copolymer, and silicone elastomer) and two drug loadings (5 and 15 mg/segment) were evaluated in at least one of two independent studies for up to 28 days in vivo. Inter-study comparison of in vivo release, vaginal tissue, and plasma concentrations for similar formulations demonstrated good reproducibility of the animal model. Mean estimates for a 28-day in vivo release ranged from 0.35 to 3.17 mg UC781 per segment. Mean proximal vaginal tissue levels (adjacent to the IVR segment) were 8-410 ng/g and did not change significantly with time for most formulations. Distal vaginal tissue levels of UC781 were 6- to 49-fold lower than proximal tissue levels. Mean UC781 plasma levels were low for all formulations, at 0.09-0.58 ng/mL. All formulations resulted in similar UC781 concentrations in vaginal tissue and plasma, except the low loading polyurethane group which provided significantly lower levels. Loading dependent release and pharmacokinetics were only clearly observed for the polyurethane matrix. Based on these results, intravaginal ring segments loaded with UC781 led to vaginal tissue concentrations ranging from below to approximately two orders of magnitude higher than UC781's EC50 under in vitro conditions (2.8 ng/mL), with little influence by polymer matrix or UC781 loading. Moreover, these findings support the use of rabbit vaginal pharmacokinetic studies in preclinical testing of microbicide intravaginal rings.
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Affiliation(s)
- Meredith R Clark
- CONRAD, Department of Obstetrics and Gynecology, Eastern Virginia Medical School, 1911 North Fort Myer Drive, Suite 900, Arlington, VA, 22209, USA,
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Abstract
UC781 is potent, hydrophobic, non-nucleotide reverse transcriptase inhibitor (NNRTI) against the human immunodeficiency virus (HIV). UC781 is currently being investigated for use as a potential HIV microbicide. A study in rhesus macaques demonstrated that a 100-mg UC781-loaded silicone elastomer vaginal ring released limited amounts of UC781 into the vaginal fluid and tissue after 28 days. The reason for this was due to the hydrophobic nature and limited aqueous solubility of UC781. This study describes the manufacture of UC781-loaded polyethylene vinyl acetate (PEVA) vaginal rings, which have an improved in vitro release rate of UC781 when compared to UC781-loaded silicone elastomer vaginal rings. The study demonstrates that the UC781 in the PEVA rings is mostly in its amorphous form due to the rings being manufactured above UC781's melting point. Furthermore, the rings do not show any signs of UC781 degradation, such as the presence of UC22.
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Boonyarattanakalin K, Viernstein H, Wolschann P, Lawtrakul L. Influence of Ethanol as a Co-Solvent in Cyclodextrin Inclusion Complexation: A Molecular Dynamics Study. Sci Pharm 2015; 83:387-99. [PMID: 26839825 PMCID: PMC4727776 DOI: 10.3797/scipharm.1412-08] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 02/09/2015] [Indexed: 11/22/2022] Open
Abstract
Molecular dynamics (MD) simulations were used to investigate the dynamics and host-guest interactions of the inclusion complexes between a potent anti-HIV agent, UC781, and three different types of cyclodextrins (CDs) including βCD, 2,6-dimethyl-βCD (MβCD), and 2-hydroxypropyl-βCD (HPβCD) in aqueous solution with ethanol (EtOH) as a co-solvent. The MD simulation results revealed that EtOH as the co-solvent and the type of cyclodextrin affected the inclusion complex formation. From this study, UC781/MβCD provided the most stable inclusion complex. The competition for the cavity of βCD between UC781 and EtOH and the ensuing occupation of βCD cavities by EtOH resulted in a weaker interaction between βCD and UC781. In HPβCD, a supramolecular complex of UC781−HPβCD−EtOH was formed. The EtOH could easily fill the residual void space of the interior of unoccupied HPβCD due to the movement of UC781. In MβCD, the strong hydrogen bond interactions between the UC781 amide group and the secondary hydroxyl groups of MβCD significantly stabilized the inclusion complex in the presence of EtOH.
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Affiliation(s)
- Kanokthip Boonyarattanakalin
- School of Bio-Chemical Engineering and Technology, Sirindhorn International Institute of Technology, Thammasat University, Pathum Thani 12121, Thailand
| | - Helmut Viernstein
- Department of Pharmaceutical Technology and Biopharmaceutics, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Peter Wolschann
- Department of Pharmaceutical Technology and Biopharmaceutics, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Luckhana Lawtrakul
- School of Bio-Chemical Engineering and Technology, Sirindhorn International Institute of Technology, Thammasat University, Pathum Thani 12121, Thailand
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Development of HIV-1 rectal-specific microbicides and colonic tissue evaluation. PLoS One 2014; 9:e102585. [PMID: 25025306 PMCID: PMC4099179 DOI: 10.1371/journal.pone.0102585] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Accepted: 06/20/2014] [Indexed: 11/26/2022] Open
Abstract
The gastrointestinal tract is structurally and functionally different from the vagina. Thus, the paradigm of topical microbicide development and evaluation has evolved to include rectal microbicides (RMs). Our interest was to create unique RM formulations to safely and effectively deliver antiretroviral drugs to mucosal tissue. RMs were designed to include those that spread and coat all surfaces of the rectum and distal colon rapidly (liquid) and those that create a deformable, erodible barrier and remain localized at the administration site (gel). Tenofovir (TFV) (1%) was formulated as an aqueous thermoreversible fluid and a carbopol-based aqueous hydrogel. Lipid-based liquid and gel formulations were prepared for UC781 (0.1%) using isopropyl myristate and GTCC (Caprylic/Capric Triglycerides), respectively. Formulations were characterized for pH, viscosity, osmolality, and drug content. Pre-clinical testing incorporated ex vivo colonic tissue obtained through surgical resections and flexible sigmoidoscopy (flex sig). As this was the first time using tissue from both sources side-by-side, the ability to replicate HIV-1 was compared. Efficacy of the RM formulations was tested by applying the products with HIV-1 directly to polarized colonic tissue and following viral replication. Safety of the formulations was determined by MTT assay and histology. All products had a neutral pH and were isoosmolar. While HIV-1BaL and HIV-1JR-CSF alone and in the presence of semen had similar replication trends between surgically resected and flex sig tissues, the magnitude of viral replication was significantly better in flex sig tissues. Both TFV and UC781 formulations protected the colonic tissue, regardless of tissue source, from HIV-1 and retained tissue viability and architecture. Our in vitro and ex vivo results show successful formulation of unique RMs. Moreover, the results of flex sig and surgically resected tissues were comparable suggesting the incorporation of both in pre-clinical testing algorithms.
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A Randomized, Comparative Safety Study of a Prefilled Plastic and User-Filled Paper Applicator With Candidate Microbicide Tenofovir 1% Gel. Sex Transm Dis 2013; 40:476-81. [DOI: 10.1097/olq.0b013e3182927ab1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Microbicides are topically applied, user controlled dosage forms that are being developed to prevent the transmission of HIV during coitus. Early candidates focused on coitally dependent dosage forms such as gels and creams. More recent development has focused on broadening the coitally dependent options through the introduction of films and fast dissolving tablets. Additionally, it has become important to have longer acting products to minimize the burden of user compliance and thus vaginal rings have been developed providing sustained delivery of antiretroviral drugs. This chapter discusses the history of microbicides along with a detailed description of coitally dependent products, gels, films, tablets diaphragms, as well as coitally independent dosage forms such as vaginal rings and the introduction of a new technology, electrospun fibers.
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Affiliation(s)
- L C Rohan
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh Magee Women's Research Institute, Pittsburgh, PA, USA,
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Anton PA, Cranston RD, Kashuba A, Hendrix CW, Bumpus NN, Richardson-Harman N, Elliott J, Janocko L, Khanukhova E, Dennis R, Cumberland WG, Ju C, Carballo-Diéguez A, Mauck C, McGowan I. RMP-02/MTN-006: A phase 1 rectal safety, acceptability, pharmacokinetic, and pharmacodynamic study of tenofovir 1% gel compared with oral tenofovir disoproxil fumarate. AIDS Res Hum Retroviruses 2012; 28:1412-21. [PMID: 22943559 DOI: 10.1089/aid.2012.0262] [Citation(s) in RCA: 122] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
This study was designed to assess the safety, acceptability, pharmacokinetic (PK), and pharmacodynamic (PD) responses to rectal administration of tenofovir (TFV) 1% vaginally formulated gel and oral tenofovir disoproxil fumarate (TDF). This study was designed as a phase 1, randomized, two-site (United States), double-blind, placebo-controlled study of sexually abstinent men and women. Eighteen participants received a single 300-mg exposure of oral TDF and were then randomized 2:1 to receive a single and then seven daily exposures of rectal TFV or hydroxyethyl cellulose (HEC) placebo gel. Safety endpoints included clinical adverse events (AEs) and mucosal safety parameters. Blood and colonic biopsies were collected for PK analyses and ex vivo HIV-1 challenge. No serious AEs were reported. However, AEs were significantly increased with 7-day TFV gel use, most prominently with gastrointestinal AEs (p=0.002). Only 25% of participants liked the TFV gel. Likelihood of use "if somewhat protective" was ∼75% in both groups. Indices of mucosal damage showed minimal changes. Tissue TFV diphosphate (TFV-DP) C(max) 30 min after single rectal exposure was 6-10 times greater than single oral exposure; tissue TFV-DP was 5.7 times greater following 7-day versus single rectal exposure. In vivo exposure correlated with significant ex vivo tissue infectibility suppression [single-rectal: p=0.12, analysis of covariance (ANCOVA) p=0.006; 7-day rectal: p=0.02, ANCOVA p=0.005]. Tissue PK-PD was significantly correlated (p=0.002). We conclude that rectal dosing with TFV 1% gel resulted in greater TFV-DP tissue detection than oral dosing with reduced ex vivo biopsy infectibility, enabling PK-PD correlations. On the basis of increased gastrointestinal AEs, rectally applied, vaginally formulated TFV was not entirely safe or acceptable, suggesting the need for alternative rectal-specific formulations.
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Affiliation(s)
- Peter A. Anton
- Center for HIV Prevention Research, UCLA AIDS Institute, Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Ross D. Cranston
- Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Angela Kashuba
- Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Craig W. Hendrix
- Departments of Medicine and Pharmacology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Namandjé N. Bumpus
- Departments of Medicine and Pharmacology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | | | - Julie Elliott
- Center for HIV Prevention Research, UCLA AIDS Institute, Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Laura Janocko
- Magee-Womens Research Institute, University of Pittsburgh Medical School, Pittsburgh, Pennsylvania
| | - Elena Khanukhova
- Center for HIV Prevention Research, UCLA AIDS Institute, Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Robert Dennis
- Computing Technology Research Laboratory (CTRL), David Geffen School of Medicine at UCLA, Los Angeles, California
| | | | - Chuan Ju
- Department of Biostatistics, UCLA School of Public Health, Los Angeles, California
| | - Alex Carballo-Diéguez
- HIV Center for Clinical and Behavioral Studies, Columbia University, New York, New York
| | | | - Ian McGowan
- Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
- Magee-Womens Research Institute, University of Pittsburgh Medical School, Pittsburgh, Pennsylvania
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The safety, persistence, and acceptability of an antiretroviral microbicide candidate UC781. J Acquir Immune Defic Syndr 2012; 60:337-43. [PMID: 22495787 DOI: 10.1097/qai.0b013e3182575914] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE : To evaluate the persistence and acceptability of a minimally absorbed vaginal gel antiretroviral designed to block the acquisition of HIV. METHODS : Sixty healthy women aged 18-45 participated in a phase-1 randomized placebo-controlled trial of a vaginal gel containing the nonnucleoside reverse transcriptase inhibitor UC781. Women underwent a single timed exposure ranging from 0 to 8 hours and were followed for 35 days. Safety was assessed by symptoms, physical exam, laboratory evaluation, and colposcopy. Persistence was assessed by drug levels in cervicovaginal lavage (CVL) and vaginal swab specimens. RESULTS : The participants' mean age was 26 years; 77% were white. The most frequently reported adverse events were genitourinary; however, the placebo and UC781 arms had a similar distribution of mild and moderate genitourinary events. All colposcopic findings were superficial. Measuring systemic UC781 levels in the plasma revealed that 2 (5%) women in the UC781 gel group had detectable UC781; however, the amount was below the limits of quantification (2.5 ng/mL) in both participants. UC781 was detected in 37 of 40 CVL samples obtained 1-2 days after drug exposure and initial CVL; the median level of UC781 was 4965 pmol/mL, significantly higher than the known IC50 of 10 pmol/mL. Eighty percent of participants reported that they would use the product if it were found to be protective against HIV. CONCLUSION : In this population of HIV-uninfected women, the gel was well tolerated and acceptable. Active levels of drug were detected in CVL and vaginal swab specimens at 1-2 days at concentrations supporting the role for daily dosing.
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The importance of the vaginal delivery route for antiretrovirals in HIV prevention. Ther Deliv 2012; 2:1535-50. [PMID: 22468220 DOI: 10.4155/tde.11.126] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The HIV/AIDS pandemic continues to be a global health priority, with high rates of new HIV-I infections persisting in young women. One HIV prevention strategy is topical pre-exposure prophylactics or microbicides, which are applied vaginally or rectally to protect the user from HIV and possibly other sexually transmitted infections. Vaginal microbicide delivery will be the focus of this review. Multiple nonspecific and specific antiretroviral microbicide products have been clinically evaluated, and many are in preclinical development, The events of HIV mucosal transmission and dynamics of the cervicovaginal environment should be considered for successful vaginal microbicide delivery. Beyond conventional vaginal formulations, intravaginal rings, tablets and films are employed as platforms in the hope to increase the likelihood of microbicide use. Furthermore, combining multiple antiretrovirals within a given formulation, combining a microbicide product with a vaginal device and integrating novel drug-delivery strategies within a microbicide product are approaches to successful vaginal-microbicide delivery.
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Kiser PF, Mahalingam A, Fabian J, Smith E, Damian FR, Peters JJ, Katz DF, Elgendy H, Clark MR, Friend DR. Design of Tenofovir–UC781 Combination Microbicide Vaginal Gels. J Pharm Sci 2012; 101:1852-64. [DOI: 10.1002/jps.23089] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2011] [Revised: 01/04/2012] [Accepted: 02/02/2012] [Indexed: 11/10/2022]
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UC781 microbicide gel retains anti-HIV activity in cervicovaginal lavage fluids collected following twice-daily vaginal application. Antimicrob Agents Chemother 2012; 56:3592-6. [PMID: 22508307 DOI: 10.1128/aac.00452-12] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The potent nonnucleoside reverse transcriptase inhibitor UC781 has been safety tested as a vaginal microbicide gel formulation for prevention of HIV-1 sexual transmission. To investigate whether UC781 retained anti-infective activity following exposure to the female genital tract, we conducted an ex vivo analysis of the UC781 levels and antiviral activity in cervicovaginal lavage (CVL) fluids from 25 Thai women enrolled in a 14-day safety trial of twice-daily vaginal application of two concentrations of the UC781 microbicide gel. CVL samples were collected from women in the 0.1% (n = 5), 0.25% (n = 15), and placebo (n = 5) gel arms following the first application of gel (T(15 min)) and 8 to 24 h after the final application (T(8-24 h)) and separated into cell-free (CVL-s) and pelletable (CVL-p) fractions. As UC781 is highly hydrophobic, there were significantly higher levels of UC781 in the CVL-p samples than in the CVL-s samples for the UC781 gel arms. In T(8-24 h) CVL-p samples, 2/5 and 13/15 samples collected from the 0.1% and 0.25% UC781 gel arms, respectively, efficiently blocked infection with ≥ 4 log(10) 50% tissue culture infective dose (TCID(50)) of a CCR5-tropic CRF01_AE HIV-1 virus stock. Independent of the arm, the 11 CVL-p samples with UC781 levels of ≥ 5 μg/CVL sample reduced infectious HIV by ≥ 4 log(10) TCID(50). Our results suggest that the levels and anti-infective activities of UC781 gel formulations are likely to be associated with a cellular or pelletable component in CVL samples. Therefore, cellular and pelletable fractions should be assayed for drug levels and anti-infective activity in preclinical studies of candidate microbicides.
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Majid A, Redfield RR, Gilliam BL. The use of preexposure treatments for HIV prophylaxis. HIV AIDS-RESEARCH AND PALLIATIVE CARE 2012; 4:17-28. [PMID: 22347807 PMCID: PMC3280625 DOI: 10.2147/hiv.s25082] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Infection with human immunodeficiency virus remains a global concern with a significant number of incident infections still reported worldwide. The use of prophylaxis prior to exposure to the virus to prevent infection has been a growing area of recent research. Results in nonhuman primates and clinical trials in high-risk patient populations using preexposure prophylaxis have shown promising results in terms of efficacy and safety, especially relating to oral preexposure prophylaxis. The potential use of oral antiretroviral agents traditionally used for human immunodeficiency virus treatment as prophylaxis raises interesting considerations, such as the best agents available for such a role, long-term safety in healthy individuals, and the potential development of resistance to these agents should infection occur. From a public health perspective, the cost-effectiveness of implementing this preventive strategy has not been fully defined at this point in time.
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Affiliation(s)
- Adrian Majid
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, USA
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Combinations of 3-hydroxyphthalic anhydride-modified ovalbumin with antiretroviral drug-based microbicide candidates display synergistic and complementary effects against HIV-1 infection. J Acquir Immune Defic Syndr 2011; 56:384-92. [PMID: 21239999 DOI: 10.1097/qai.0b013e31820a4a8d] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The development of a safe, effective, and affordable microbicide to prevent the sexual transmission of HIV combination is urgently needed. Our previous studies demonstrated that 3-hydroxyphthalic anhydride-modified chicken ovalbumin (HP-OVA) exhibited potent antiviral activity against a broad spectrum of HIV, simian immunodeficiency virus, and herpes simplex virus, making it a promising candidate as a component of combination microbicide. We intended to evaluate potential the synergistic anti-HIV-1 effect of HP-OVA in combination with antiretroviral drug (ARV)-based microbicide candidates. METHODS The antiviral activity of HP-OVA and the ARVs, including HIV-1 entry inhibitors (T20, C52L, NB64, NBD556, AMD3100, and Maraviroc) and reverse transcriptase inhibitors (Tenofovir, UC781, and TMC120), tested alone or in combination, against HIV-1 X4 and R5 viruses, including some drug-resistant strains, was determined in MT-2 and peripheral blood mononuclear cells using p24 assay. The immune responses induced by HP-OVA that was applied in the vaginas of rats were detected by enzyme-linked immunosorbent assay. RESULTS When each of these ARV-based microbicide candidates was combined with HP-OVA, synergistic activity was observed against infection by both X4 and R5 strains, and the degree of synergy differed in each case. HP-OVA was highly effective against several ARV-resistant HIV-1 strains, suggesting that combining HP-OVA with these ARV-based microbicide candidates might work cooperatively against both drug-sensitive and -resistant HIV-1 strains. Human body fluids and human proteins had little or no effects on HP-OVA-mediated inhibitory activity against HIV-1 infection. HP-OVA formulated in the universal gel maintained its antiviral activity for at least 1 month and only induced weak immune responses after its multiple applications in the vaginas of rats. CONCLUSIONS Synergistic and complementary effects against infection by a broad spectrum of HIV-1 strains were observed by combining HP-OVA with the ARV-based microbicide candidates. These findings provide a sound scientific platform for the development of a safe, effective, and affordable combination microbicide to prevent the sexual transmission of HIV and other sexually transmissible viruses.
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Clark MR, Johnson TJ, McCabe RT, Clark JT, Tuitupou A, Elgendy H, Friend DR, Kiser PF. A hot-melt extruded intravaginal ring for the sustained delivery of the antiretroviral microbicide UC781. J Pharm Sci 2011; 101:576-87. [PMID: 21976110 DOI: 10.1002/jps.22781] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Revised: 09/01/2011] [Accepted: 09/14/2011] [Indexed: 11/06/2022]
Abstract
Microbicide intravaginal rings (IVRs) are a promising woman-controlled strategy for preventing sexual transmission of human immunodeficiency virus (HIV). An IVR was prepared and developed from polyether urethane (PU) elastomers for the sustained delivery of UC781, a highly potent nonnucleoside reverse transcriptase inhibitor of HIV-1. PU IVRs containing UC781 were fabricated using a hot-melt extrusion process. In vitro release studies of UC781 demonstrated that UC781 release profiles are loading dependent and resemble matrix-type, diffusion-limited kinetics. The in vitro release methods employed over predicted the in vivo release rates of UC781 in rabbits. Accelerated stability studies showed good chemical stability of UC781 in prototype formulations, but surface crystallization of UC781 was observed following long-term storage at higher UC781 loadings, unless formulated with a polyvinylpyrrolidone/glycerol surface coating. Mechanical stability testing of prototype rings showed moderate stiffening upon storage. The PU and UC781 had minimal to no impact on viability, tissue integrity, barrier function, or cytokine expression in the tissue irritation model, and UC781 was shown to be delivered to and permeate through this tissue construct in vitro. Overall, UC781 was formulated in a stable PU IVR and provided controlled release of UC781 both in vitro and in vivo.
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Affiliation(s)
- Meredith R Clark
- CONRAD, Department of Obstetrics and Gynecology, Eastern Virginia Medical School, Arlington, Virginia 22209, USA
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Anton PA, Saunders T, Elliott J, Khanukhova E, Dennis R, Adler A, Cortina G, Tanner K, Boscardin J, Cumberland WG, Zhou Y, Ventuneac A, Carballo-Diéguez A, Rabe L, McCormick T, Gabelnick H, Mauck C, McGowan I. First phase 1 double-blind, placebo-controlled, randomized rectal microbicide trial using UC781 gel with a novel index of ex vivo efficacy. PLoS One 2011; 6:e23243. [PMID: 21969851 PMCID: PMC3182160 DOI: 10.1371/journal.pone.0023243] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Accepted: 07/11/2011] [Indexed: 12/16/2022] Open
Abstract
OBJECTIVES Successful control of the HIV/AIDS pandemic requires reduction of HIV-1 transmission at sexually-exposed mucosae. No prevention studies of the higher-risk rectal compartment exist. We report the first-in-field Phase 1 trial of a rectally-applied, vaginally-formulated microbicide gel with the RT-inhibitor UC781 measuring clinical and mucosal safety, acceptability and plasma drug levels. A first-in-Phase 1 assessment of preliminary pharmacodynamics was included by measuring changes in ex vivo HIV-1 suppression in rectal biopsy tissue after exposure to product in vivo. METHODS HIV-1 seronegative, sexually-abstinent men and women (N = 36) were randomized in a double-blind, placebo-controlled trial comparing UC781 gel at two concentrations (0.1%, 0.25%) with placebo gel (1∶1∶1). Baseline, single-dose exposure and a separate, 7-day at-home dosing were assessed. Safety and acceptability were primary endpoints. Changes in colorectal mucosal markers and UC781 plasma drug levels were secondary endpoints; ex vivo biopsy infectibility was an ancillary endpoint. RESULTS All 36 subjects enrolled completed the 7-14 week trial (100% retention) including 3 flexible sigmoidoscopies, each with 28 biopsies (14 at 10 cm; 14 at 30 cm). There were 81 Grade 1 adverse events (AEs) and 8 Grade 2; no Grade 3, 4 or procedure-related AEs were reported. Acceptability was high, including likelihood of future use. No changes in mucosal immunoinflammatory markers were identified. Plasma levels of UC781 were not detected. Ex vivo infection of biopsies using two titers of HIV-1(BaL) showed marked suppression of p24 in tissues exposed in vivo to 0.25% UC781; strong trends of suppression were seen with the lower 0.1% UC781 concentration. CONCLUSIONS Single and 7-day topical rectal exposure to both concentrations of UC781 were safe with no significant AEs, high acceptability, no detected plasma drug levels and no significant mucosal changes. Ex vivo biopsy infections demonstrated marked suppression of HIV infectibility, identifying a potential early biomarker of efficacy. (Registered at ClinicalTrials.gov; #NCT00408538).
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Affiliation(s)
- Peter A Anton
- Center for HIV Prevention Research, UCLA AIDS Institute, Department of Medicine, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, California, United States of America.
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Verma NA, Lee AC, Herold BC, Keller MJ. Topical prophylaxis for HIV prevention in women: becoming a reality. Curr HIV/AIDS Rep 2011; 8:104-13. [PMID: 21424725 DOI: 10.1007/s11904-011-0075-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Strategies to protect against sexual transmission of HIV include the development of products formulated for topical application, which limit the toxicities associated with systemic oral pre-exposure prophylaxis. Following several clinical trial failures, attention is now focused on antiretroviral (ARV) agents. Highly potent ARV topical formulations provide a female-controlled, targeted, and feasible option for HIV prevention. A recently completed tenofovir gel trial was the first to demonstrate significant protection against HIV acquisition. Topical ARVs have the advantage of delivering high concentration of drug at the site of transmission of HIV, with low systemic absorption. Sustained-release formulations, such as intravaginal rings, will likely improve adherence and can be designed to provide controlled and continuous delivery of ARV combinations. Further studies to test alternative dosing strategies and pharmacokinetic/pharmacodynamic relationships in the genital tract will provide valuable information as the field strives to improve upon the promising tenofovir gel trial results.
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Affiliation(s)
- Natasha A Verma
- Department of Pediatrics, Division of Infectious Diseases, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Forchheimer Building, Room 702, Bronx, NY 10461, USA.
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Ramjee G. Antiretroviral-based microbicides and oral pre-exposure prophylaxis for HIV prevention. Future Virol 2011. [DOI: 10.2217/fvl.11.64] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Numerous HIV prevention options have been tested, with limited success. Microbicides have been the focus of research specifically targeted to prevent new infections among women. After decades of research using non-HIV-specific microbicides, we now have proof of concept for antiretroviral-based microbicides. Issues of drug resistance, frequency of HIV testing and adherence to treatment remain to be explored. Drugs used for HIV treatment and with good safety profiles have been shown to provide protection to men who have sex with men. Ethical issues surrounding cost, access, future design of HIV prevention trials and composition of the prevention package offered to trial participants remain. The role of advocacy and market research will be crucial to ensure effective interventions are accessed and supported. There is renewed hope in the HIV prevention field with collective efforts needed to ensure we get the new prevention tools and options into the hands of men and women at risk of HIV infection. The purpose of this paper is to provide a review of existing research and identify issues for future enquiry.
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Affiliation(s)
- Gita Ramjee
- HIV Prevention Research Unit, Medical Research Council, Durban, South Africa and Department of Epidemiology & Population Health, London School of Hygiene & Tropical Medicine, London, UK
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Selhorst P, Vazquez AC, Terrazas-Aranda K, Michiels J, Vereecken K, Heyndrickx L, Weber J, Quiñones-Mateu ME, Ariën KK, Vanham G. Human immunodeficiency virus type 1 resistance or cross-resistance to nonnucleoside reverse transcriptase inhibitors currently under development as microbicides. Antimicrob Agents Chemother 2011; 55:1403-13. [PMID: 21282453 PMCID: PMC3067143 DOI: 10.1128/aac.01426-10] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 11/29/2010] [Accepted: 01/19/2011] [Indexed: 11/20/2022] Open
Abstract
Microbicides based on nonnucleoside reverse transcriptase inhibitors (NNRTIs) are currently being developed to protect women from HIV acquisition through sexual contact. However, the large-scale introduction of these products raises two major concerns. First, when these microbicides are used by undiagnosed HIV-positive women, they could potentially select for viral resistance, which may compromise subsequent therapeutic options. Second, NNRTI-based microbicides that are inactive against NNRTI-resistant strains might promote the selective transmission of these viruses. In order to address these concerns, drug resistance was selected in vitro by the serial passage of three viral isolates from subtypes B and C and CRF02_AG (a circulating recombinant form) in activated peripheral blood mononuclear cells (PBMCs) under conditions of increasing concentrations of three NNRTIs (i.e., TMC120, UC781, and MIV-160) that are currently being developed as candidate microbicides. TMC120 and MIV-160 displayed a high genetic barrier to resistance development, whereas resistance to UC781 emerged rapidly, similarly to efavirenz and nevirapine. Phenotypically, the selected viruses appeared to be highly cross-resistant to current first-line therapeutic NNRTIs (i.e., delavirdine, nevirapine, and efavirenz), although they retained some susceptibility to the more recently developed NNRTIs lersivirine and etravirine. The ability of UC781, TMC120, and MIV-160 to inhibit the in vitro-selected NNRTI-resistant viruses was also limited, although residual activity could be observed for the candidate microbicide NNRTI MIV-170. Interestingly, only four p2/p7/p1/p6/PR/RT/INT recombinant NNRTI-resistant viruses (i.e., TMC120-resistant VI829, EFV-resistant VI829, MIV-160-resistant VI829, and EFV-resistant MP568) showed impairments in replicative fitness. Overall, these in vitro analyses demonstrate that due to potential cross-resistance, the large-scale introduction of single-NNRTI-based microbicides should be considered with caution.
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Affiliation(s)
- Philippe Selhorst
- Department of Microbiology, Virology Unit, Institute of Tropical Medicine, Nationalestraat 155, B-2000 Antwerp, Belgium.
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Benzalkonium chloride causes colposcopic changes and increased susceptibility to genital herpes infection in mice. Sex Transm Dis 2011; 37:579-84. [PMID: 20803781 DOI: 10.1097/olq.0b013e3181dac410] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Colposcopy is widely used in clinical microbicide safety testing but not in preclinical small animal studies. Endoscopic colposcopy could be employed in small animals allowing colposcopy to be used as one component in a multifactorial safety testing paradigm. STUDY DESIGN We conducted dose-response studies in mice using 2%, 0.2%, or 0.02% benzalkonium chloride (BZK) as the test compound, and using multiple safety end points that included endoscopic colposcopy, susceptibility to vaginal HSV-2 infection, histology, and entry of inflammatory cells into the vagina. RESULTS Animals treated with 0.2% or higher BZK experienced vaginal toxicities detectable by all tests used including colposcopy. In contrast, 0.02% BZK produced no significant changes except by histology in which a significant thinning of the vaginal epithelium was seen. CONCLUSION Endoscopic colposcopy detected microbicide-elicited changes in the mouse vagina with similar sensitivity to the other endpoints used in these studies and would appear to be useful as part of a multifactorial microbicide safety testing paradigm in mice.
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Piret J, Bergeron MG. Should microbicides be controlled by women or by physicians? Int J Infect Dis 2010; 14 Suppl 3:e14-7. [PMID: 20932483 DOI: 10.1016/j.ijid.2010.02.2256] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2009] [Revised: 10/19/2009] [Accepted: 02/25/2010] [Indexed: 11/24/2022] Open
Abstract
In 2007, nearly 7000 new cases of HIV infection occurred each day. There is a constant increase in the proportion of women newly infected with HIV in the global population; this increase is particularly high in some areas of the world such as sub-Saharan Africa. Microbicides are products that are being developed to empower women against HIV. First- and second-generation microbicides are broad-spectrum products that include surface active agents, vaginal defense enhancers, and blocking agents. Third-generation microbicides are HIV-specific and include replication and entry inhibitors formulated as gels or as vaginal rings. However, there is a concern that antiretroviral-based microbicides could lead to drug resistance if they are used by HIV-positive women who are unaware of their HIV status. To reach the highest number of women possible, microbicides should be available over-the-counter, which might not be the case with antiretroviral-based formulations. In contrast, non-antiretroviral-based microbicides will have the advantage of being initiated and controlled by women themselves and they will not jeopardize the use of life-saving drugs.
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Affiliation(s)
- Jocelyne Piret
- Centre de Recherche en Infectiologie, Université Laval, CHUQ, Pavillon CHUL, 2705 Boulevard Laurier, Québec, Canada.
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Abstract
Microbicide clinical trials have dominated biomedical HIV prevention research in the past decade. Two generations of microbicides have gone through large-scale human clinical trials. Candidate microbicides assessed in clinical trials in Africa have fallen into the categories of surfactants, polyanionic entry inhibitors, or vaginal milieu protectors. These include compounds such as nonoxynol-9, SAVVY, cellulose sulphate, Carraguard, PRO 2000, and BufferGel. Disappointingly, none of the products have shown efficacy against HIV. Each successive trial has benefited from the lessons learned in preceding trials. The trials have provided important lessons in basic, clinical, social, and behavioural science. More importantly, we have learned that the concept of a vaginally inserted product for HIV prevention is acceptable by women. We have now reached an end of an era of clinical testing with non-HIV-specific microbicides and move forward to testing novel strategies of antiretroviral therapeutic products such as preexposure prophylaxis (PrEP) for HIV prevention. PrEP for vaginal administration in various formulations is being tested to continue our commitment to providing more HIV prevention options to millions of women worldwide.
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Kim PS, Read SW. Nanotechnology and HIV: potential applications for treatment and prevention. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2010; 2:693-702. [DOI: 10.1002/wnan.118] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Peter S. Kim
- Division of AIDS, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Sarah W. Read
- Division of AIDS, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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Abstract
PURPOSE OF REVIEW Microbicide research has been in the forefront of scientific literature in recent months. Results of large-scale clinical trials have been announced with resultant investigations into the factors that may have contributed to the disappointing outcomes of the most promising candidates. This review takes into consideration clinical, basic scientific and behavioural research published on microbicides in the past 12-18 months. RECENT FINDINGS Two trials testing PRO 2000, a sulphated polymer, suggested that it has no effect on HIV. Basic science research revealed several facts such as the loss of antiviral activity of microbicides in the presence of seminal plasma. Methodological models suggested that dilution factors might impact on measures of efficacy. Advancement into safety testing of highly specific antiretroviral products such as tenofovir and UC781 for both rectal and vaginal use shows promise. Development of drug delivery systems such as intravaginal rings may alleviate some of the adherence challenges faced when using coitally dependant products. SUMMARY In the recent past, microbicide research has had disappointing outcomes. However, it has also provided a better understanding of factors that may reduce effectiveness of promising products, enabling the field to be better equipped to select and test new products.
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Ventuneac A, Carballo-Diéguez A, McGowan I, Dennis R, Adler A, Khanukhova E, Price C, Saunders T, Siboliban C, Anton P. Acceptability of UC781 gel as a rectal microbicide among HIV-uninfected women and men. AIDS Behav 2010; 14:618-28. [PMID: 19757017 PMCID: PMC2865630 DOI: 10.1007/s10461-009-9611-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2009] [Accepted: 08/25/2009] [Indexed: 11/25/2022]
Abstract
We studied the overall acceptability of UC781 gel formulation when applied rectally. Ten women and twenty-six men, all HIV-uninfected, were enrolled in a Phase 1, randomized, blinded, placebo-controlled safety and acceptability study of the vaginal microbicide gel UC781 applied rectally. Participants were randomized to three groups: 0.1% UC781 gel, 0.25% UC781 gel, or a placebo gel. Acceptability was assessed using structured questionnaires and qualitative in-depth interviews. After using UC781 gel rectally for seven consecutive days, participants’ reports suggest that a UC781 gel formulation is highly acceptable and comparable to a placebo gel. The gels received favorable ratings overall and on attributes such as color, smell and consistency. All of the participants reported high intentions to use a gel like the one they used in this study. Acceptability research is essential in early phases of microbicide development to identify potential problems, understand user preferences, and introduce changes if needed.
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Affiliation(s)
- Ana Ventuneac
- HIV Center for Clinical and Behavioral Studies, New York State Psychiatric Institute and Columbia University, 1051 Riverside Drive, Unit 15, New York, NY 10032, USA.
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3-hydroxyphthalic anhydride-modified chicken ovalbumin exhibits potent and broad anti-HIV-1 activity: a potential microbicide for preventing sexual transmission of HIV-1. Antimicrob Agents Chemother 2010; 54:1700-11. [PMID: 20194691 DOI: 10.1128/aac.01046-09] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Heterosexual transmission is the primary route by which women acquire human immunodeficiency virus (HIV)/AIDS. Thus, development of woman-controlled topical microbicides for prevention of sexual transmission of HIV is urgently needed. Here we report that 3-hydroxyphthalic anhydride-modified chicken ovalbumin (HP-OVA) exhibits potent antiviral activity against a broad spectrum of human immunodeficiency virus type 1 (HIV-1) isolates with different genotypes and biotypes. Its antiviral activity is correlated with the percentages of the chemically modified and unmodified lysines and arginines in OVA. HP-OVA inhibits HIV-1 fusion and entry through multiple mechanisms of action, including (i) blocking gp120 binding to CD4 and (ii) interfering with gp41 six-helix bundle formation. Because of the widespread availability and established safety profile of OVA, HP-OVA has good potential to be developed as an effective, safe, and affordable microbicide for prevention of HIV sexual transmission.
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Buckheit RW, Watson KM, Morrow KM, Ham AS. Development of topical microbicides to prevent the sexual transmission of HIV. Antiviral Res 2010; 85:142-58. [PMID: 19874851 PMCID: PMC2815091 DOI: 10.1016/j.antiviral.2009.10.013] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Revised: 10/12/2009] [Accepted: 10/16/2009] [Indexed: 01/07/2023]
Abstract
Women comprise almost 50% of the population of people living with HIV and the majority of these women contracted the virus through sexual transmission in monogamous relationships in the developing world. In these environments, where women are not empowered to protect themselves through the negotiation of condom use, effective means of preventing HIV transmission are urgently needed. In the absence of an approved and effective vaccine, microbicides have become the strategy of choice to provide women with the ability to prevent HIV transmission from their infected partners. Topical microbicides are agents specifically developed and formulated for use in either the vaginal or rectal environment that prevent infection by sexually transmitted infectious organisms, including pathogenic viruses, bacteria and fungi. Although a microbicidal product will have many of the same properties as other anti-infective agents and would be similarly developed through human clinical trials, microbicide development bears its own challenges related to formulation and delivery and the unique environment in which the product must act, as well as the requirement to develop a product that is acceptable to the user. Herein, perspectives based on preclinical and clinical microbicide development experience, which have led to an evolving microbicide development algorithm, will be discussed. This article forms part of a special issue of Antiviral Research marking the 25th anniversary of anti-retroviral drug discovery and development, Vol 85, issue 1, 2010.
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Affiliation(s)
- Robert W Buckheit
- ImQuest BioSciences, Inc., 7340 Executive Way, Suite R, Frederick, MD 21704, USA.
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Abstract
HIV infection rates in the developing world remain a serious problem. One potential approach to reduce infection rates is to use products known as microbicides, referred to herein as microbicide drug products (MDPs). These are drugs capable of, when administered topically to the vagina (or rectum), interfering with infection by one or more mechanisms. This review article covers the latest pharmaceutical developments in the area of microbicides dosage forms and delivery systems. These products are principally designed for use in the developing world and must therefore address cultural and societal issues generally unknown in the developed world. The first-generation microbicides evaluated clinically were principally polyanions. These drugs, administered intravaginally as gels, were found to be ineffective in preventing transmission of HIV from men to women. Second-generation drugs such as tenofovir, dapivirine, and UC781 are reverse transcriptase inhibitors developed as gels formulations and intravaginal rings (IVRs). Gels are considered coitally-related products while IVRs are coitally-independent systems designed to release the drug over a four-week period or possibly longer (up to 3 or 4 months). Other dosage forms under development include fast dissolving films, tablets/capsules, and possibly vaginal sponges. Dual protection systems are also under development. These systems include formulations capable of preventing HIV infection along with a second drug capable of preventing conception or other viral infections such as HSV.
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The safety of candidate vaginal microbicides since nonoxynol-9: a systematic review of published studies. AIDS 2009; 23:1245-54. [PMID: 19474652 DOI: 10.1097/qad.0b013e32832b4271] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To gain a greater understanding of published safety data for candidate vaginal microbicides. DESIGN A systematic review of human safety trials of candidate vaginal microbicides - agents designed to protect women against HIV and other sexually transmitted infections. METHODS Trials were published in peer-reviewed journals, and publication cut-off was August week 4, 2008. Trials of nonoxynol-9 were excluded, as were trials without a control group, trials that enrolled only male participants or reported on the investigation of a product for the treatment of a genital infection. RESULTS Twenty-one trials of 11 products, involving 1465 women, satisfied review criteria. Most trials reported on genital epithelial findings and urogenital symptoms and a number reported a range of other local and systemic toxicity endpoints. Trials were generally of short duration (2 weeks or less) with small sample sizes. There were few findings of significant difference between women in active and control arms. Among the products assessed in more than one study, there were significantly more genital findings with intact epithelium in recipients of PRO2000 [relative risk (RR) 1.68, 95% confidence interval (CI) 1.08-2.60] and a lower incidence of bacterial vaginosis in dextrin sulphate recipients (RR 0.61, 95% CI 0.42-0.88). CIs were generally very wide, and most studies were unable to exclude differences of a substantial magnitude between treated and control women. CONCLUSION Larger and longer safety studies are necessary to detect clinically important toxicities, including those that indicate a potential increase in HIV risk, and provide assurance that agents are ready for large-scale effectiveness trials.
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Garg AB, Nuttall J, Romano J. The future of HIV microbicides: challenges and opportunities. Antivir Chem Chemother 2009; 19:143-50. [PMID: 19374141 DOI: 10.1177/095632020901900401] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
HIV microbicides are topical, self-administered products aimed at preventing or reducing HIV infection in women and may represent the most promising strategy for combating the HIV/AIDS epidemic at the present time. Although a safe and effective microbicide has yet to be identified, all products tested in Phase III trials to date have been vaginal gels containing non-specific compounds with modest potency that had to be applied close to the time of sexual intercourse. Issues regarding these early generation products were further complicated by widely publicized cases of halted efficacy trials. However, as a result of each of these challenges, new information and essential lessons have emerged for the field. These lessons have resulted in a meaningful increase in microbicide development efforts focusing on compounds with highly potent and HIV-specific mechanisms of action, combination products, novel formulations, and carefully designed pharmacokinetic and pharmacodynamic evaluations, all of which are reasons for renewed confidence that a safe and effective microbicide is achievable.
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Affiliation(s)
- Anita B Garg
- International Partnership for Microbicides, Inc, Silver Spring, MD, USA.
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Selection of a simian-human immunodeficiency virus strain resistant to a vaginal microbicide in macaques. J Virol 2009; 83:5067-76. [PMID: 19279098 DOI: 10.1128/jvi.00055-09] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PSC-RANTES binds to CCR5, inhibits human immunodeficiency virus type 1 (HIV-1) entry, and has been shown as a vaginal microbicide to protect rhesus macaques from a simian-human immunodeficiency virus chimera (SHIV(SF162-p3)) infection in a dose-dependent manner. In this study, env gene sequences from SHIV(SF162-p3)-infected rhesus macaques treated with PSC-RANTES were analyzed for possible drug escape variants. Two specific mutations located in the V3 region of gp120 (K315R) and C-helical domain of gp41 (N640D) were identified in a macaque (m584) pretreated with a 100 microM dose of PSC-RANTES. These two env mutations were found throughout infection (through week 77) but were found at only low frequencies in the inoculating SHIV(SF162-p3) stock and in the other SHIV(SF162-p3)-infected macaques. HIV-1 env genes from macaque m584 (env(m584)) and from inoculating SHIV(SF162-p3) (env(p3)) were cloned into an HIV-1 backbone. Increases in 50% inhibitory concentrations to PSC-RANTES with env(m584) were modest (sevenfold) and most pronounced in cells expressing rhesus macaque CCR5 as compared to human CCR5. Nonetheless, virus harboring env(m584), unlike inoculating virus env(p3), could replicate even at the highest tissue culture PSC-RANTES concentrations (100 nM). Dual-virus competitions revealed a dramatic increase in fitness of chimeric virus containing env(m584) (K315R/N640D) over that containing env(p3), but again, only in rhesus CCR5-expressing cells. This study is the first to describe the immediate selection and infection of a drug-resistant SHIV variant in the face of a protective vaginal microbicide, PSC-RANTES. This rhesus CCR5-specific/PSC- RANTES resistance selection is particularly alarming given the relative homogeneity of the SHIV(SF162-p3) stock compared to the potential exposure to a heterogeneous HIV-1 population in human transmission.
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Rohan LC, Sassi AB. Vaginal drug delivery systems for HIV prevention. AAPS JOURNAL 2009; 11:78-87. [PMID: 19194802 DOI: 10.1208/s12248-009-9082-7] [Citation(s) in RCA: 126] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2008] [Accepted: 12/24/2008] [Indexed: 11/30/2022]
Abstract
Microbicides have become a principal focus for HIV prevention strategies. The successful design of drug delivery systems for vaginal microbicide drug candidates brings with it a multitude of challenges. It is imperative that the chemical and physical characteristics of the drug candidate and its mechanism of action be clearly understood and considered to successfully deliver and target drug candidates efficiently. In addition, an understanding of the dynamic nature of the vaginal environment, the tissue and innate barriers present, as well as patient preferences are critical considerations in the design of effective microbicide products. Although the majority of drug candidates clinically evaluated to date have been delivered using conventional semisolid aqueous-based gel dosage forms, drug delivery system design has recently been extended to include advanced delivery systems such as vaginal rings, quick-dissolve films, and tablets. Ultimately, it may be necessary to develop multiple dosage platforms for a single active agent to provide users with options that can be used within the constraints of their social environment, personal choice, and environmental conditions.
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Affiliation(s)
- Lisa Cencia Rohan
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
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Cutler B, Justman J. Vaginal microbicides and the prevention of HIV transmission. THE LANCET. INFECTIOUS DISEASES 2008; 8:685-97. [PMID: 18992405 DOI: 10.1016/s1473-3099(08)70254-8] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Worldwide, nearly half of all individuals living with HIV are now women, who acquire the virus largely by heterosexual exposure. With an HIV vaccine likely to be years away, topical microbicide formulations applied vaginally or rectally are being investigated as another strategy for HIV prevention. A review of preclinical and clinical research on the development of microbicides formulated to prevent vaginal HIV transmission yielded 118 studies: 73 preclinical and 45 clinical. Preclinical research included in-vitro assays and cervical explant models, as well as animal models. Clinical research included phase I and II/IIb safety studies, and phase III efficacy studies. Whereas most phase I and phase II clinical trials have found microbicide compounds to be safe and well tolerated, phase III trials completed to date have not demonstrated efficacy in preventing HIV transmission. Topical microbicides are grouped into five classes of agents, based on where they disrupt the pathway of sexual transmission of HIV. These classes include surfactants/membrane disruptors, vaginal milieu protectors, viral entry inhibitors, reverse transcriptase inhibitors, and a fifth group whose mechanism is unknown. The trajectory of microbicide development has been toward agents that block more specific virus-host cell interactions. Microbicide clinical trials face scientifically and ethically complex issues, such as the choice of placebo gel, the potential for viral resistance, and the inclusion of HIV-infected participants. Assessment of combination agents will most likely advance this field of research.
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Affiliation(s)
- Blayne Cutler
- Department of Medicine, Mailman School of Public Health, Columbia University, New York, NY 10032, USA
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