1
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Murphy DJ, Lim D, Armstrong R, McCoy CF, Bashi YHD, Boyd P, Derrick T, Spence P, Devlin B, Malcolm RK. Refining the in vitro release test method for a dapivirine-releasing vaginal ring to match in vivo performance. Drug Deliv Transl Res 2021:10.1007/s13346-021-01081-7. [PMID: 34674162 DOI: 10.1007/s13346-021-01081-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/11/2021] [Indexed: 11/27/2022]
Abstract
Previously reported in vitro release test methods for drug-releasing vaginal rings containing poorly water-soluble drugs have described use of water-alcohol systems or surfactant solutions in efforts to maintain sink conditions. Here, as part of efforts to more closely match in vitro and in vivo release for the 25 mg dapivirine matrix-type silicone elastomer vaginal ring for HIV prevention, we have investigated alternatives to the 1:1 v/v water/isopropanol medium described previously. Specifically, we evaluated dapivirine release from rings into (i) monophasic water/isopropanol mixtures of varying compositions and (ii) biphasic buffer/octanol systems using pH 4.2 and pH 7.0 buffers. The rate and mechanism of dapivirine release were dependent upon the isopropanol concentration in the release medium, in accordance with the observed trend in drug solubility. At 0 and 10% v/v isopropanol concentrations, dapivirine release followed a partition-controlled mechansim. For media containing ≥ 20% v/v isopropanol, in vitro release of dapivirine was significantly increased and obeyed permeation-controlled kinetics. Cumulative release of ~3.5 mg dapivirine over 28 days was obtained using a water isopropanol mixture containing 20% v/v isopropanol, similar to the ~4 mg dapivirine released in vivo. Dapivirine release into the biphasic buffer/octanol system (intended to mimic the fluid/tissue environment in vivo) was constrained by the limited solubility of dapivirine in the buffer component in which the ring resided, such that cumulative dapivirine release was consistently lower than that observed with the 20% v/v isopropanol in water medium. Release into the biphasic system was also pH dependent, in line with dapivirine's pKa and with potential implications for in vivo release and absorption in women with elevated vaginal pH.
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Affiliation(s)
- Diarmaid J Murphy
- School of Pharmacy, Queen's University Belfast, Belfast, BT9 7BL, UK
| | - Deanna Lim
- School of Pharmacy, Queen's University Belfast, Belfast, BT9 7BL, UK
| | - Ryan Armstrong
- School of Pharmacy, Queen's University Belfast, Belfast, BT9 7BL, UK
| | - Clare F McCoy
- School of Pharmacy, Queen's University Belfast, Belfast, BT9 7BL, UK
| | | | - Peter Boyd
- School of Pharmacy, Queen's University Belfast, Belfast, BT9 7BL, UK
| | - Tiffany Derrick
- International Partnership for Microbicides, Silver Spring, MD, USA
| | - Patrick Spence
- International Partnership for Microbicides, Silver Spring, MD, USA
| | - Bríd Devlin
- International Partnership for Microbicides, Silver Spring, MD, USA
| | - R Karl Malcolm
- School of Pharmacy, Queen's University Belfast, Belfast, BT9 7BL, UK.
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2
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Arany P, Papp I, Zichar M, Regdon G, Béres M, Szalóki M, Kovács R, Fehér P, Ujhelyi Z, Vecsernyés M, Bácskay I. Manufacturing and Examination of Vaginal Drug Delivery System by FDM 3D Printing. Pharmaceutics 2021; 13:1714. [PMID: 34684007 PMCID: PMC8539995 DOI: 10.3390/pharmaceutics13101714] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/07/2021] [Accepted: 10/12/2021] [Indexed: 11/17/2022] Open
Abstract
Vaginal drug delivery systems can provide a long-term and constant liberation of the active pharmaceutical ingredient even for months. For our experiment, FDM 3D printing was used to manufacture the vaginal ring samples from thermoplastic polyurethane filament, which enables fast manufacturing of complex, personalized medications. 3D printing can be an excellent alternative instead of industrial manufacturing, which is complicated and time-consuming. In our work, the 3D printed vaginal rings were filled manually with jellified metronidazole or chloramphenicol for the treatment of bacterial vaginosis. The need for manual filling was certified by the thermogravimetric and heatflow assay results. The manufactured samples were analyzed by an Erweka USP type II Dissolution Apparatus, and the dissolution profile can be distinguished based on the applied jellifying agents and the API's. All samples were considered non-similar based on the pairwise comparison. The biocompatibility properties were determined by prolonged MTT assay on HeLa cells, and the polymer could be considered non-toxic. Based on the microbiological assay on E. coli metronidazole and chitosan containing samples had bactericidal effects while just metronidazole or just chitosan containing samples bacteriostatic effect. None of these samples showed a fungistatic or fungicide effect against C. albicans. Based on our results, we successfully manufactured 3D printed vaginal rings filled with jellified metronidazole.
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Affiliation(s)
- Petra Arany
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Debrecen, Nagyerdei Körút 98, H-4032 Debrecen, Hungary; (P.A.); (P.F.); (Z.U.); (M.V.)
- Doctoral School of Pharmaceutical Sciences, University of Debrecen, Nagyerdei Körút 98, H-4032 Debrecen, Hungary
| | - Ildikó Papp
- Department of Computer Graphics and Image Processing, Faculty of Informatics, University of Debrecen, Kassai út 26, H-4028 Debrecen, Hungary; (I.P.); (M.Z.)
| | - Marianna Zichar
- Department of Computer Graphics and Image Processing, Faculty of Informatics, University of Debrecen, Kassai út 26, H-4028 Debrecen, Hungary; (I.P.); (M.Z.)
| | - Géza Regdon
- Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary;
| | - Mónika Béres
- Department of Medical Imaging, Faculty of Medicine, University of Debrecen, Nagyerdei Krt. 98, H-4032 Debrecen, Hungary;
| | - Melinda Szalóki
- Department of Biomaterials and Prosthetic Dentistry, Faculty of Dentistry, University of Debrecen, Nagyerdei Körút 98, H-4032 Debrecen, Hungary;
| | - Renátó Kovács
- Department of Medical Microbiology, Faculty of Medicine and Pharmacy, University of Debrecen, Nagyerdei Körút 98, H-4032 Debrecen, Hungary;
| | - Pálma Fehér
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Debrecen, Nagyerdei Körút 98, H-4032 Debrecen, Hungary; (P.A.); (P.F.); (Z.U.); (M.V.)
| | - Zoltán Ujhelyi
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Debrecen, Nagyerdei Körút 98, H-4032 Debrecen, Hungary; (P.A.); (P.F.); (Z.U.); (M.V.)
| | - Miklós Vecsernyés
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Debrecen, Nagyerdei Körút 98, H-4032 Debrecen, Hungary; (P.A.); (P.F.); (Z.U.); (M.V.)
| | - Ildikó Bácskay
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Debrecen, Nagyerdei Körút 98, H-4032 Debrecen, Hungary; (P.A.); (P.F.); (Z.U.); (M.V.)
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3
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Use of simulated vaginal and menstrual fluids to model in vivo discolouration of silicone elastomer vaginal rings. INTERNATIONAL JOURNAL OF PHARMACEUTICS-X 2021; 3:100081. [PMID: 34027386 PMCID: PMC8120934 DOI: 10.1016/j.ijpx.2021.100081] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 04/28/2021] [Indexed: 01/13/2023]
Abstract
Vaginal rings releasing antiretrovirals – either alone or in combination with contraceptive progestins – are being developed for prevention of human immunodeficiency virus (HIV) transmission via vaginal sex. Following Phase I trials, significant discolouration was observed on the surface of investigational silicone elastomer antiretroviral-contraceptive matrix-type vaginal rings containing either 25 mg dapivirine or 200 mg dapivirine plus levonorgestrel. In this study, potential causes of the discolouration have been assessed in vitro using simulated vaginal and menstrual fluids (SVF and SMF, respectively) to model in vivo exposure. The fluid compositions also included hydrogen peroxide (H2O2), hydrogen peroxide plus a copper intrauterine device (IUD), or synthetic dyes (representing personal care and household cleaning products). No discolouration was observed for rings exposed to SVF + hydrogen peroxide (with or without an IUD). However, the SVF + dye compositions showed significant ring discolouration, with staining patterns similar to those observed with rings that had been exposed to highly-coloured personal care and household cleaning products during clinical trial use. Exposure of rings to SMF compositions invariably caused yellow surface discolouration, dark spotting and markings, similar to the staining patterns observed following clinical use. The darker marks on the ring surface were identified as blood debris derived from the SMF. The study indicates that surface discolouration of rings in vivo can be attributed to exposure to menstrual fluid or highly coloured personal care or household cleaning products. Discolouration of the rings was not associated with any specific safety risks for the user, though severe discolouration could potentially impact acceptability and adherence.
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4
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Tietz K, Klein S. In Vitro Methods for Evaluating Drug Release of Vaginal Ring Formulations-A Critical Review. Pharmaceutics 2019; 11:pharmaceutics11100538. [PMID: 31623277 PMCID: PMC6836189 DOI: 10.3390/pharmaceutics11100538] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 10/09/2019] [Accepted: 10/14/2019] [Indexed: 12/28/2022] Open
Abstract
The vagina is a promising site for both local and systemic drug delivery and represents an interesting administration route for compounds with poor oral bioavailability. Whereas most of the currently marketed dosage forms were designed as immediate release formulations, intravaginal rings (IVRs) offer the possibility of a controlled vaginal drug delivery over several weeks or months. For a long time, the development of IVRs was limited to steroid-releasing formulations. Recently, IVRs have witnessed a surge of new interest as promising delivery systems for microbicides. Therefore, various novel IVR designs have been introduced. To ensure that only safe and effective IVRs will be administered to patients, it is important to properly distinguish between IVRs with desired and undesired release performance. In vitro methods for evaluating drug release of IVRs that present with sufficient predictive capacity for in vivo drug release, and discriminatory power with regard to IVRs quality, are an essential tool for this purpose. The objective of the present review article is to present the current status of in vitro drug release testing of IVRs and to critically discuss current compendial and non-official in vitro drug release methods with regard to their discriminatory power and in vivo predictivity.
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Affiliation(s)
- Katharina Tietz
- Center of Drug Absorption and Transport, Institute of Biopharmaceutics and Pharmaceutical Technology, Department of Pharmacy, Felix-Hausdorff-Str. 3, University of Greifswald, Greifswald 17489, Germany
| | - Sandra Klein
- Center of Drug Absorption and Transport, Institute of Biopharmaceutics and Pharmaceutical Technology, Department of Pharmacy, Felix-Hausdorff-Str. 3, University of Greifswald, Greifswald 17489, Germany.
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5
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In vitro release testing methods for drug-releasing vaginal rings. J Control Release 2019; 313:54-69. [PMID: 31626862 DOI: 10.1016/j.jconrel.2019.10.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 10/05/2019] [Accepted: 10/08/2019] [Indexed: 12/28/2022]
Abstract
Drug-releasing vaginal rings are torus-shaped devices, generally fabricated from thermoplastic polymers or silicone elastomers, used to administer pharmaceutical drugs to the human vagina for periods typically ranging from three weeks to twelve months. One of the most important product performance tests for vaginal rings is the in vitro release test. Although it has been fifty years since a vaginal ring device was first described in the scientific literature, and despite seven drug-releasing vaginal rings having been approved for market, there is no universally accepted method for testing in vitro drug release, and only one non-compendial shaking incubator method (for the estradiol-releasing ring Estring®) is described in the US Food and Drug Administration's Dissolution Methods Database. Here, for the first time, we critically review the diverse range of test methods that have been described in the scientific literature for testing in vitro release of drug-releasing vaginal rings. Issues around in vitro-in vivo correlation and modelling of in vitro release data are also discussed.
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6
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McBride JW, Malcolm RK, Dias N, Cameron D, Offord RE, Hartley O, Kett VL, Devlin B, Boyd P. Development and pharmacokinetics of a combination vaginal ring for sustained release of dapivirine and the protein microbicide 5P12-RANTES. Int J Pharm 2019; 564:207-213. [PMID: 30999049 DOI: 10.1016/j.ijpharm.2019.04.040] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 04/12/2019] [Accepted: 04/13/2019] [Indexed: 12/16/2022]
Abstract
The past fifteen years have witnessed a resurgence of interest in vaginal ring technologies for drug delivery applications, mostly driven by the impetus for development of vaginally-administered antiretroviral microbicides to help reduce the high acquisition rates for human immunodeficiency virus (HIV) among Sub-Saharan African women. Currently, the lead candidate microbicide is a 28-day silicone elastomer vaginal ring releasing dapivirine (Ring-004), an experimental non-nucleoside reverse transcriptase inhibitor. The ring was tested in two pivotal Phase III clinical studies in 2016 and is currently undergoing review by the European Medicines Agency. Recently, we described a new type of silicone elastomer vaginal ring offering sustained release of the protein molecule 5P12-RANTES, a potent experimental chemokine analogue that potently blocks the HIV CCR5 coreceptor. Building on our previous work, here we report the preclinical development of a new combination vaginal ring that offers sustained release of both 5P12-RANTES and dapivirine, in which the 5P12-RANTES is incorporated into an exposed core within the ring body and the dapivirine in the sheath. In this way, in vitro release of dapivirine matches closely that for Ring-004. Also, we report the pharmacokinetic testing of this combination ring formulation in sheep, where vaginal concentrations of both drugs are maintained over 28 days at levels potentially useful for preventing HIV infection in women.
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Affiliation(s)
- John W McBride
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK
| | - R Karl Malcolm
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK
| | | | | | - Robin E Offord
- Mintaka Foundation for Medical Research, Geneva, Switzerland
| | - Oliver Hartley
- Mintaka Foundation for Medical Research, Geneva, Switzerland; Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Vicky L Kett
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Brid Devlin
- International Partnership for Microbicides, Silver Spring, MD 20910, USA
| | - Peter Boyd
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK.
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7
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Murphy DJ, Desjardins D, Boyd P, Dereuddre-Bosquet N, Stimmer L, Caldwell A, Le Grand R, Kelly C, van Roey J, Malcolm RK. Impact of ring size and drug loading on the pharmacokinetics of a combination dapivirine-darunavir vaginal ring in cynomolgus macaques. Int J Pharm 2018; 550:300-308. [PMID: 30153490 DOI: 10.1016/j.ijpharm.2018.08.051] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 08/22/2018] [Accepted: 08/24/2018] [Indexed: 01/05/2023]
Abstract
This work investigates the impact of vaginal ring size and drug loading on the in vitro release, safety, ease of fit, and pharmacokinetics in cynomolgus macaques of matrix-type silicone elastomer vaginal rings containing a combination of the non-nucleoside reverse transcriptase inhibitor dapivirine and the protease inhibitor darunavir. Drug-free and drug-loaded vaginal rings having three different geometries were manufactured by reaction injection molding. In vitro drug release was assessed using both a solvent/water mixture and a vaginal fluid simulant. Macaques fitted with drug-free vaginal rings for 28 days were assessed by colposcopy, cytological evaluation of cervico-vaginal lavage and histological evaluation of tissue after ring removal. The 20 × 4.5 mm combination ring, deemed most appropriate for vaginal fit and comfort in the macaques, was evaluated for pharmacokinetics over 28 days. Substantial differences were observed in the in vitro release profiles between the three ring sizes. However, these differences were not manifest in vivo, where measured drug concentrations after 20 × 4.5 mm ring use were not significantly different from those reported previously with a 25 × 6 mm ring. These results suggest that ring placement and fit is an important species-specific study parameter that should be optimised prior to pharmacokinetic testing.
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Affiliation(s)
- Diarmaid J Murphy
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK.
| | - Delphine Desjardins
- Université Paris Sud, INSERM, CEA, DRF-Immunology of Viral Infections and Autoimmune Diseases Department (IMVA), U1184, IDMIT Infrastructure, Fontenay-aux-Roses, France.
| | - Peter Boyd
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK.
| | - Nathalie Dereuddre-Bosquet
- Université Paris Sud, INSERM, CEA, DRF-Immunology of Viral Infections and Autoimmune Diseases Department (IMVA), U1184, IDMIT Infrastructure, Fontenay-aux-Roses, France.
| | - Lev Stimmer
- Molecular Imaging Research Center, CEA-INSERM US27/U1169, 18 route du Panorama, 92265 Fontenay-aux-Roses, France.
| | - Anna Caldwell
- Mass Spectrometry Facility, King's College London, London SE1 9NH, UK.
| | - Roger Le Grand
- Université Paris Sud, INSERM, CEA, DRF-Immunology of Viral Infections and Autoimmune Diseases Department (IMVA), U1184, IDMIT Infrastructure, Fontenay-aux-Roses, France.
| | - Charles Kelly
- Dental Institute, Guy's Hospital, King's College London, London SE1 9RT, UK.
| | - Jens van Roey
- Janssen GPH, Turnhoutseweg 30, 2340 Beerse, Belgium.
| | - R Karl Malcolm
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK.
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8
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Loksha YM, Pedersen EB. Asymmetric Synthesis of Potential Precursors of the HIV Drug MC1220 and Its Analogues by Hydrogenation of (1-Arylvinyl)pyrimidines. J Heterocycl Chem 2018. [DOI: 10.1002/jhet.3168] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Yasser M. Loksha
- Nucleic Acid Centre, Department of Physics, Chemistry and Pharmacy; University of Southern Denmark; Campusvej 55 DK-5230 Odense M Denmark
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy; Sinai University; Al-Arish North Sinai Egypt
| | - Erik B. Pedersen
- Nucleic Acid Centre, Department of Physics, Chemistry and Pharmacy; University of Southern Denmark; Campusvej 55 DK-5230 Odense M Denmark
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9
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Murphy DJ, Amssoms K, Pille G, Clarke A, O'Hara M, van Roey J, Malcolm RK. Sustained release of the candidate antiretroviral peptides T-1249 and JNJ54310516-AFP from a rod insert vaginal ring. Drug Deliv Transl Res 2018; 6:234-42. [PMID: 26787615 PMCID: PMC4854936 DOI: 10.1007/s13346-015-0273-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Administration of biomacromolecular drugs in effective quantities from conventional vaginal rings is hampered by poor drug permeability in the polymers from which rings are commonly constructed. Here, we report the formulation development and testing of rod insert rings for sustained release of the candidate antiretroviral peptides T-1249 and JNJ54310516-AFP (JNJ peptide), both of which have potential as HIV microbicides. Rod inserts were prepared comprising antiviral peptides T-1249 or JNJ peptide in combination with a hydrophilic excipient (sodium chloride, sodium glutamate, lactose or zinc acetate) dispersed at different loadings within a medical grade silicone elastomer. The inserts were tested for weight change and swelling when immersed in simulated vaginal fluid (SVF). Dye migration into the inserts was also assessed visually over 28 days. In vitro release of T-1249 and JNJ peptide from rings containing various insert types was tested. Weight change and degree of swelling of rods immersed in SVF was dependent on the type and concentration of excipient present. The rods displayed the following rank order in terms of weight change: sodium glutamate > zinc acetate ≈ sodium chloride > lactose. The weight change and degree of swelling of the inserts did not correlate with the level of dye uptake observed. In vitro release of T-1249 was improved through addition of lactose, sodium chloride and sodium glutamate, while release of JNJ peptide was improved through addition of sodium chloride or sodium glutamate. Sustained release of hydrophobic peptides can be achieved using a rod insert ring design formulated to include a hydrophilic excipient. Release rates were dependent upon the type of excipient used. The degree of release improvement with different inserts partially reflects their ability to imbibe surrounding fluid and swell in aqueous environments.
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Affiliation(s)
- Diarmaid J Murphy
- School of Pharmacy, Queen's University Belfast, Belfast, BT9 7BL, UK.
| | - Katie Amssoms
- Janssen Research and Development, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - Geert Pille
- Janssen Research and Development, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - Aileen Clarke
- School of Pharmacy, Queen's University Belfast, Belfast, BT9 7BL, UK
| | - Marc O'Hara
- School of Pharmacy, Queen's University Belfast, Belfast, BT9 7BL, UK
| | - Jens van Roey
- Janssen Research and Development, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - R Karl Malcolm
- School of Pharmacy, Queen's University Belfast, Belfast, BT9 7BL, UK
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10
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Derby N, Aravantinou M, Kenney J, Ugaonkar SR, Wesenberg A, Wilk J, Kizima L, Rodriguez A, Zhang S, Mizenina O, Levendosky K, Cooney ML, Seidor S, Gettie A, Grasperge B, Blanchard J, Piatak M, Lifson JD, Fernández-Romero J, Zydowsky TM, Robbiani M. An intravaginal ring that releases three antiviral agents and a contraceptive blocks SHIV-RT infection, reduces HSV-2 shedding, and suppresses hormonal cycling in rhesus macaques. Drug Deliv Transl Res 2017; 7:840-858. [PMID: 28600625 PMCID: PMC5656733 DOI: 10.1007/s13346-017-0389-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Women globally need access to multipurpose prevention technologies (MPTs) that prevent human immunodeficiency virus (HIV), sexually transmitted infections that increase HIV acquisition/transmission risk, and unintended pregnancy. Seeking an MPT with activity against HIV, herpes simplex virus-2 (HSV-2), and human papillomavirus (HPV), we developed a prototype intravaginal ring (IVR), the MZCL IVR, which released the antiviral agents MIV-150, zinc acetate, and carrageenan (MZC for short) and the contraceptive levonorgestrel (LNG). Previously, we showed that an MZC gel has potent activity against immunodeficiency viruses, HSV-2, and HPV and that the MZCL (MZC with LNG) IVR releases all four components in macaques in vivo at levels associated with efficacy. Vaginal fluid from treated macaques has in vitro activity against HIV, HSV-2, and HPV. Herein, we assessed the ability of the MZCL IVR to protect macaques against repeated co-challenge with HSV-2 and SHIV-RT (simian immunodeficiency virus [SIV] containing the reverse transcriptase gene from HIV) and prevent hormonal cycling. We evaluated in vivo drug release in co-challenged macaques by measuring drug levels in blood and vaginal fluid and residual drug levels in used IVRs. The MZCL IVR significantly prevented SHIV-RT infection, reduced HSV-2 vaginal shedding, and prevented cycling. No non-nucleoside HIV reverse transcriptase inhibitor (NNRTI)-resistant SHIV was detected in macaques that became infected after continuous exposure to MZC from the IVR. Macaques wearing the MZCL IVR also had carrageenan levels in vaginal fluid expected to protect from HPV (extrapolated from mice) and LNG levels in blood associated with contraceptive efficacy. The MZCL IVR is a promising MPT candidate that warrants further development.
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MESH Headings
- Alphapapillomavirus/drug effects
- Alphapapillomavirus/physiology
- Animals
- Antiviral Agents/administration & dosage
- Antiviral Agents/pharmacology
- Carrageenan/administration & dosage
- Carrageenan/pharmacology
- Contraceptive Agents, Female/administration & dosage
- Contraceptive Agents, Female/pharmacology
- Contraceptive Devices, Female
- Disease Models, Animal
- Drug Therapy, Combination/methods
- Female
- Herpes Simplex/prevention & control
- Herpesvirus 2, Human/drug effects
- Herpesvirus 2, Human/physiology
- Humans
- Macaca mulatta
- Menstrual Cycle
- Pyridines/administration & dosage
- Pyridines/pharmacology
- Simian Acquired Immunodeficiency Syndrome/prevention & control
- Urea/administration & dosage
- Urea/analogs & derivatives
- Urea/pharmacology
- Vaginal Creams, Foams, and Jellies/administration & dosage
- Vaginal Creams, Foams, and Jellies/pharmacology
- Virus Shedding/drug effects
- Zinc Acetate/administration & dosage
- Zinc Acetate/pharmacology
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Affiliation(s)
- Nina Derby
- Population Council, 1230 York Avenue, New York, NY, 10065, USA.
| | | | - Jessica Kenney
- Population Council, 1230 York Avenue, New York, NY, 10065, USA
| | | | - Asa Wesenberg
- Population Council, 1230 York Avenue, New York, NY, 10065, USA
| | - Jolanta Wilk
- Population Council, 1230 York Avenue, New York, NY, 10065, USA
| | - Larisa Kizima
- Population Council, 1230 York Avenue, New York, NY, 10065, USA
| | - Aixa Rodriguez
- Population Council, 1230 York Avenue, New York, NY, 10065, USA
| | - Shimin Zhang
- Population Council, 1230 York Avenue, New York, NY, 10065, USA
| | - Olga Mizenina
- Population Council, 1230 York Avenue, New York, NY, 10065, USA
| | | | | | - Samantha Seidor
- Population Council, 1230 York Avenue, New York, NY, 10065, USA
| | - Agegnehu Gettie
- Aaron Diamond AIDS Research Center, 455 First Avenue, 7th Floor, New York, NY, 10016, USA
| | - Brooke Grasperge
- Tulane Primate Research Center, 18703 Three Rivers Road, Covington, LA, 70433-8915, USA
| | - James Blanchard
- Tulane Primate Research Center, 18703 Three Rivers Road, Covington, LA, 70433-8915, USA
| | - Michael Piatak
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD, 21702-1201, USA
| | - Jeffrey D Lifson
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD, 21702-1201, USA
| | - José Fernández-Romero
- Population Council, 1230 York Avenue, New York, NY, 10065, USA
- Science Department, Borough of Manhattan Community College, The City University of New York, 199 Chambers Street, New York, NY, 10007, USA
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11
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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 DESIGN DEVELOPMENT AND THERAPY 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] [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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McCoy CF, Murphy DJ, Boyd P, Derrick T, Spence P, Devlin B, Malcolm RK. Packing Polymorphism of Dapivirine and Its Impact on the Performance of a Dapivirine-Releasing Silicone Elastomer Vaginal Ring. J Pharm Sci 2017; 106:2015-2025. [PMID: 28456732 DOI: 10.1016/j.xphs.2017.04.026] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 03/20/2017] [Accepted: 04/17/2017] [Indexed: 02/05/2023]
Abstract
A silicone elastomer vaginal ring providing sustained release over 28 days of the anti-retroviral microbicide dapivirine has recently completed phase III clinical testing and showed moderate protection against HIV acquisition. In support of the product licensure program, we report the impact of dapivirine packing polymorphism on the thermal and solubility characteristics of dapivirine and on the in vitro performance of the 25 mg dapivirine ring product. This is the first time that polymorphism has been reported for a drug-releasing vaginal ring product. Thermal, particle size, powder X-ray diffraction, and thermodynamic solubility analyses of dapivirine polymorphic forms I and IV, both of which are persistent at room temperature and with form I being the thermodynamically stable form, were conducted for both micronized and non-micronized materials. No significant differences in solubility between DPV forms I and IV were observed in media commonly used for in vitro release testing. Matrix-type silicone elastomer vaginal rings were manufactured and the impact of dapivirine polymorphism on key in vitro parameters (compression and tensile behavior; content assay; in vitro release; residual content assay) was investigated. The data demonstrate that dapivirine packing polymorphism has no significant impact on in vitro performance of the 25 mg dapivirine vaginal ring.
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Affiliation(s)
- Clare F McCoy
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK
| | | | - Peter Boyd
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Tiffany Derrick
- International Partnership for Microbicides, Silver Spring, Maryland 20910
| | - Patrick Spence
- International Partnership for Microbicides, Silver Spring, Maryland 20910
| | - Brid Devlin
- International Partnership for Microbicides, Silver Spring, Maryland 20910
| | - R Karl Malcolm
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK.
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13
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Malcolm RK, Boyd PJ, McCoy CF, Murphy DJ. Microbicide vaginal rings: Technological challenges and clinical development. Adv Drug Deliv Rev 2016; 103:33-56. [PMID: 26829289 DOI: 10.1016/j.addr.2016.01.015] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 01/13/2016] [Accepted: 01/20/2016] [Indexed: 10/22/2022]
Abstract
Vaginal rings (VRs) are flexible, torus-shaped, polymeric devices designed to sustain delivery of pharmaceutical drugs to the vagina for clinical benefit. Following first report in a 1970 patent application, several steroid-releasing VR products have since been marketed for use in hormone replacement therapy and contraception. Since 2002, there has been growing interest in the use of VR technology for delivery of drugs that can reduce the risk of sexual acquisition of human immunodeficiency virus type 1 (HIV-1), the causative agent of acquired immunodeficiency syndrome (AIDS). Although no vaginally-administered product has yet been approved for HIV reduction/prevention, extensive research efforts are continuing and a number of VR devices offering sustained release of so-called 'HIV microbicide' compounds are currently being evaluated in late-stage clinical studies. This review article provides an overview of the published scientific literature within this important field of research, focusing primarily on articles published within peer-reviewed journal publications. Many important aspects of microbicide-releasing VR technology are discussed, with a particular emphasis on the technological, manufacturing and clinical challenges that have emerged in recent years.
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14
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Boyd P, Fetherston SM, McCoy CF, Major I, Murphy DJ, Kumar S, Holt J, Brimer A, Blanda W, Devlin B, Malcolm RK. Matrix and reservoir-type multipurpose vaginal rings for controlled release of dapivirine and levonorgestrel. Int J Pharm 2016; 511:619-629. [PMID: 27473275 DOI: 10.1016/j.ijpharm.2016.07.051] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 07/22/2016] [Accepted: 07/23/2016] [Indexed: 12/31/2022]
Abstract
A matrix-type silicone elastomer vaginal ring providing 28-day continuous release of dapivirine (DPV) - a lead candidate human immunodeficiency virus type 1 (HIV-1) microbicide compound - has recently demonstrated moderate levels of protection in two Phase III clinical studies. Here, next-generation matrix and reservoir-type silicone elastomer vaginal rings are reported for the first time offering simultaneous and continuous in vitro release of DPV and the contraceptive progestin levonorgestrel (LNG) over a period of between 60 and 180days. For matrix-type vaginal rings comprising initial drug loadings of 100, 150 or 200mg DPV and 0, 16 or 32mg LNG, Day 1 daily DPV release values were between 4132 and 6113μg while Day 60 values ranged from 284 to 454μg. Daily LNG release ranged from 129 to 684μg on Day 1 and 2-91μg on Day 60. Core-type rings comprising one or two drug-loaded cores provided extended duration of in vitro release out to 180days, and maintained daily drug release rates within much narrower windows (either 75-131μg/day or 37-66μg/day for DPV, and either 96-150μg/day or 37-57μg/day for LNG, depending on core ring configuration and ignoring initial lag release effect for LNG) compared with matrix-type rings. The data support the continued development of these devices as multi-purpose prevention technologies (MPTs) for HIV prevention and long-acting contraception.
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Affiliation(s)
- Peter Boyd
- School of Pharmacy, Queens University Belfast, Belfast BT9 7BL, UK
| | | | - Clare F McCoy
- School of Pharmacy, Queens University Belfast, Belfast BT9 7BL, UK
| | - Ian Major
- Athlone Institute of Technology, Athlone, Ireland
| | | | - Sandeep Kumar
- School of Pharmacy, Queens University Belfast, Belfast BT9 7BL, UK
| | - Jonathon Holt
- International Partnership for Microbicides, Silver Spring, MD 20910, USA
| | - Andrew Brimer
- International Partnership for Microbicides, Silver Spring, MD 20910, USA
| | - Wendy Blanda
- International Partnership for Microbicides, Silver Spring, MD 20910, USA
| | - Brid Devlin
- International Partnership for Microbicides, Silver Spring, MD 20910, USA
| | - R Karl Malcolm
- School of Pharmacy, Queens University Belfast, Belfast BT9 7BL, UK.
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Loksha YM, Pedersen EB, Loddo R, La Colla P. Synthesis and Anti-HIV-1 Evaluation of Some Novel MC-1220 Analogs as Non-Nucleoside Reverse Transcriptase Inhibitors. Arch Pharm (Weinheim) 2016; 349:363-72. [PMID: 26996241 DOI: 10.1002/ardp.201600008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 02/23/2016] [Accepted: 02/25/2016] [Indexed: 11/11/2022]
Abstract
Some novel MC-1220 analogs were synthesized by condensation of 4,6-dichloro-N-methylpyrimidin-2-amine derivatives (1a,b and 15) and/or 4-chloro-6-methoxy-N,N,5-trimethylpyrimidin-2-amine (2a) with the sodium salt of 2,6-difluorophenylacetonitrile followed by treatment with aqueous sodium hydroxide in methanol, alkylation, reduction, halogenation, and/or acidic hydrolysis. All synthesized compounds were evaluated for their activity against HIV-1. The most active compound in this study was compound 7, which showed activity against HIV-1 comparable to that of MC-1220. The only difference in structure between compound 7 and MC-1220 is a fluoro atom instead of a CH3 group.
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Affiliation(s)
- Yasser M Loksha
- Department of Physics, Chemistry and Pharmacy, Nucleic Acid Centre, University of Southern Denmark, Odense M, Denmark.,Faculty of Pharmacy and Pharmaceutical Industries, Department of Pharmaceutical Chemistry, Sinai University, Al-Arish, North Sinai, Egypt
| | - Erik B Pedersen
- Department of Physics, Chemistry and Pharmacy, Nucleic Acid Centre, University of Southern Denmark, Odense M, Denmark
| | - Roberta Loddo
- Dipartimento di Scienze e Tecnologie Biomediche, Sezione di Microbiologia e Virologia Generale e Biotecnologie Microbiche, Universita di Cagliari, Monserrato, Italy
| | - Paolo La Colla
- Dipartimento di Scienze e Tecnologie Biomediche, Sezione di Microbiologia e Virologia Generale e Biotecnologie Microbiche, Universita di Cagliari, Monserrato, Italy
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Murphy DJ, Boyd P, McCoy CF, Kumar S, Holt JDS, Blanda W, Brimer AN, Malcolm RK. Controlling levonorgestrel binding and release in a multi-purpose prevention technology vaginal ring device. J Control Release 2016; 226:138-47. [PMID: 26878974 DOI: 10.1016/j.jconrel.2016.02.020] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 02/08/2016] [Accepted: 02/10/2016] [Indexed: 10/22/2022]
Abstract
Despite a long history of incorporating steroids into silicone elastomers for drug delivery applications, little is presently known about the propensity for irreversible drug binding in these systems. In this study, the ability of the contraceptive progestin levonorgestrel to bind chemically with hydrosilane groups in addition-cure silicone elastomers has been thoroughly investigated. Cure time, cure temperature, levonorgestrel particle size, initial levonorgestrel loading and silicone elastomer type were demonstrated to be key parameters impacting the extent of levonorgestrel binding, each through their influence on the solubility of levonorgestrel in the silicone elastomer. Understanding and overcoming this levonorgestrel binding phenomenon is critical for the ongoing development of a number of drug delivery products, including a multi-purpose technology vaginal ring device offering simultaneous release of levonorgestrel and dapivirine - a lead candidate antiretroviral microbicide - for combination HIV prevention and hormonal contraception.
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Affiliation(s)
- Diarmaid J Murphy
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, United Kingdom
| | - Peter Boyd
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, United Kingdom
| | - Clare F McCoy
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, United Kingdom
| | - Sandeep Kumar
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, United Kingdom
| | - Jonathon D S Holt
- International Partnership for Microbicides, Silver Spring, MD, United States
| | - Wendy Blanda
- International Partnership for Microbicides, Silver Spring, MD, United States
| | - Andrew N Brimer
- International Partnership for Microbicides, Silver Spring, MD, United States
| | - R Karl Malcolm
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, United Kingdom.
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17
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Abstract
PURPOSE OF REVIEW In response to the need for strategies women can use to protect themselves from HIV infection, a new class of product commonly referred to as vaginal 'microbicides' has been under development for the past few decades. Several leading products currently in development contain antiviral agents delivered in a vaginal ring. RECENT FINDINGS Research published over the past year reports advances in identification and continued formulation of specific antiviral agents that have potential for delivery in vaginal rings, including drug combinations for HIV, other sexually transmitted infections and contraception. Most products are antiretroviral reverse transcriptase inhibitors. Advances in vaginal ring design have also been reported; some of these are designed to release specific antiviral agents, while other designs could be used for multiple drugs. This review focuses both on antiviral agents and vaginal ring designs. SUMMARY Over the past year, advances continued to be made in the development of vaginal rings to deliver antiviral agents for prevention of HIV. An array of antiviral agents and vaginal ring designs to deliver these products are at various stages in the product pipeline process. Results from the first efficacy trials of an antiretroviral-containing vaginal ring are expected soon and will inform the continued development of this important product class.
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Ariën KK, Venkatraj M, Michiels J, Joossens J, Vereecken K, Van der Veken P, Heeres J, De Winter H, Heyndrickx L, Augustyns K, Vanham G. Resistance and cross-resistance profile of the diaryltriazine NNRTI and candidate microbicide UAMC01398. J Antimicrob Chemother 2016; 71:1159-68. [PMID: 26850721 DOI: 10.1093/jac/dkv501] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 12/26/2015] [Indexed: 02/03/2023] Open
Abstract
OBJECTIVES The resistance development, cross-resistance to other NNRTIs and the impact of resistance on viral replicative fitness were studied for the new and potent NNRTI UAMC01398. METHODS Resistance was selected by dose escalation and by single high-dose selection against a comprehensive panel of NNRTIs used as therapeutics and NNRTIs under investigation for pre-exposure prophylaxis of sexual HIV transmission. A panel of 27 site-directed mutants with single mutations or combinations of mutations involved in reverse transcriptase (RT) inhibitor-mediated resistance was developed and used to confirm resistance to UAMC01398. Cross-resistance to other NNRTIs was assessed, as well as susceptibility of UAMC01398-resistant HIV to diarylpyrimidine-resistant viruses. Finally, the impact of UAMC01398 resistance on HIV replicative fitness was studied. RESULTS We showed that UAMC01398 has potent activity against dapivirine-resistant HIV, that at least four mutations in the RT are required in concert for resistance and that the resistance profile is similar to rilpivirine, both genotypically and phenotypically. Resistance development to UAMC01398 is associated with a severe fitness cost. CONCLUSIONS These data, together with the enhanced safety profile and good solubility in aqueous gels, make UAMC01398 an excellent candidate for HIV topical prevention.
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Affiliation(s)
- Kevin K Ariën
- Department of Biomedical Sciences, Institute of Tropical Medicine, B-2000 Antwerp, Belgium
| | - Muthusamy Venkatraj
- Laboratory of Medicinal Chemistry, University of Antwerp, B-2000 Antwerp, Belgium
| | - Johan Michiels
- Department of Biomedical Sciences, Institute of Tropical Medicine, B-2000 Antwerp, Belgium
| | - Jurgen Joossens
- Laboratory of Medicinal Chemistry, University of Antwerp, B-2000 Antwerp, Belgium
| | - Katleen Vereecken
- Department of Biomedical Sciences, Institute of Tropical Medicine, B-2000 Antwerp, Belgium
| | - Pieter Van der Veken
- Laboratory of Medicinal Chemistry, University of Antwerp, B-2000 Antwerp, Belgium
| | - Jan Heeres
- Laboratory of Medicinal Chemistry, University of Antwerp, B-2000 Antwerp, Belgium
| | - Hans De Winter
- Laboratory of Medicinal Chemistry, University of Antwerp, B-2000 Antwerp, Belgium
| | - Leo Heyndrickx
- Department of Biomedical Sciences, Institute of Tropical Medicine, B-2000 Antwerp, Belgium
| | - Koen Augustyns
- Laboratory of Medicinal Chemistry, University of Antwerp, B-2000 Antwerp, Belgium
| | - Guido Vanham
- Department of Biomedical Sciences, Institute of Tropical Medicine, B-2000 Antwerp, Belgium Department of Biomedical Sciences, University of Antwerp, B-2000 Antwerp, Belgium
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Pharmacokinetic and Pharmacodynamic Evaluation following Vaginal Application of IQB3002, a Dual-Chamber Microbicide Gel Containing the Nonnucleoside Reverse Transcriptase Inhibitor IQP-0528 in Rhesus Macaques. Antimicrob Agents Chemother 2015; 60:1393-400. [PMID: 26666935 DOI: 10.1128/aac.02201-15] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 12/05/2015] [Indexed: 11/20/2022] Open
Abstract
We evaluated the in vivo pharmacokinetics and used a complementary ex vivo coculture assay to determine the pharmacodynamics of IQB3002 gel containing 1% IQP-0528, a nonnucleoside reverse transcriptase inhibitor (NNRTI), in rhesus macaques (RM). The gel (1.5 ml) was applied vaginally to 6 simian-human immunodeficiency (SHIV)-positive female RM. Blood, vaginal fluids, and rectal fluids were collected at 0, 1, 2, and 4 h. RM were euthanized at 4 h, and vaginal, cervical, rectal, and regional lymph node tissues were harvested. Anti-human immunodeficiency virus (HIV) activity was evaluated ex vivo by coculturing fresh or frozen vaginal tissues with activated human peripheral blood mononuclear cells (PBMCs) and measuring the p24 levels for 10 days after an HIV-1Ba-L challenge. The median levels of IQP-0528, determined using liquid chromatography-tandem mass spectroscopy (LC-MS/MS) methods, were between 10(4) and 10(5) ng/g in vaginal and cervical tissue, between 10(3) and 10(4) ng/g in rectal tissues, and between 10(5) and 10(7) ng/ml in vaginal fluids over the 4-h period. The vaginal tissues protected the cocultured PBMCs from HIV-1 infection ex vivo, with a viral inhibition range of 81 to 100% in fresh and frozen tissues that were proximal, medial, and distal relative to the cervix. No viral inhibition was detected in untreated baseline tissues. Collectively, the median drug levels observed were 5 to 7 logs higher than the in vitro 50% effective concentration (EC50) range (0.21 ng/ml to 1.29 ng/ml), suggesting that 1.5 ml of the gel delivers IQP-0528 throughout the RM vaginal compartment at levels that are highly inhibitory to HIV-1. Importantly, antiviral activity was observed in both fresh and frozen vaginal tissues, broadening the scope of the ex vivo coculture model for future NNRTI efficacy studies.
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Loksha YM, Pedersen EB, La Colla P, Loddo R. Facile synthesis of the NNRTI microbicide MC-1220 and synthesis of its phosphoramidate prodrugs. Org Biomol Chem 2015; 14:940-6. [PMID: 26608715 DOI: 10.1039/c5ob02055g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A facile and novel synthetic route to MC-1220 was achieved by condensation of 4,6-dichloro-N,N-5-trimethylpyrimidin-2-amine (1) with the sodium salt of 2,6-difluorophenylacetonitrile, followed by methylation and strong acidic hydrolysis. The prodrugs of MC-1220 were synthesized by reaction of chlorophosphoramidate derivatives (7a-e) or α-acetobromoglucose with the sodium salt of MC-1220. The stability and anti-HIV-1 activity of phosphoramidate prodrugs turned out to be comparable to those of the parent drug MC-1220.
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Affiliation(s)
- Yasser M Loksha
- Nucleic Acid Center, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
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21
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C5A Protects Macaques from Vaginal Simian-Human Immunodeficiency Virus Challenge. Antimicrob Agents Chemother 2015; 60:693-8. [PMID: 26552985 DOI: 10.1128/aac.01925-15] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 11/05/2015] [Indexed: 12/31/2022] Open
Abstract
A safe and effective vaginal microbicide could decrease human immunodeficiency virus (HIV) transmission in women. Here, we evaluated the safety and microbicidal efficacy of a short amphipathic peptide, C5A, in a rhesus macaque model. We found that a vaginal application of C5A protects 89% of the macaques from a simian-human immunodeficiency virus (SHIV-162P3) challenge. We observed no signs of lesions or inflammation in animals vaginally treated with repeated C5A applications. With its noncellular cytotoxic activity and rare mechanism of action, C5A represents an attractive microbicidal candidate.
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Zhan P, Pannecouque C, De Clercq E, Liu X. Anti-HIV Drug Discovery and Development: Current Innovations and Future Trends. J Med Chem 2015; 59:2849-78. [PMID: 26509831 DOI: 10.1021/acs.jmedchem.5b00497] [Citation(s) in RCA: 229] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The early effectiveness of combinatorial antiretroviral therapy (cART) in the treatment of HIV infection has been compromised to some extent by rapid development of multidrug-resistant HIV strains, poor bioavailability, and cumulative toxicities, and so there is a need for alternative strategies of antiretroviral drug discovery and additional therapeutic agents with novel action modes or targets. From this perspective, we first review current strategies of antiretroviral drug discovery and optimization, with the aid of selected examples from the recent literature. We highlight the development of phosphate ester-based prodrugs as a means to improve the aqueous solubility of HIV inhibitors, and the introduction of the substrate envelope hypothesis as a new approach for overcoming HIV drug resistance. Finally, we discuss future directions for research, including opportunities for exploitation of novel antiretroviral targets, and the strategy of activation of latent HIV reservoirs as a means to eradicate the virus.
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Affiliation(s)
- Peng Zhan
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University , 44, West Culture Road, 250012, Jinan, Shandong, P. R. China
| | - Christophe Pannecouque
- Rega Institute for Medical Research, Katholieke Universiteit Leuven , Minderbroedersstraat 10, B-3000 Leuven, Belgium
| | - Erik De Clercq
- Rega Institute for Medical Research, Katholieke Universiteit Leuven , Minderbroedersstraat 10, B-3000 Leuven, Belgium
| | - Xinyong Liu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University , 44, West Culture Road, 250012, Jinan, Shandong, P. R. China
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23
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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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24
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SR-2P vaginal microbicide gel provides protection against herpes simplex virus 2 when administered as a combined prophylactic and postexposure therapeutic. Antimicrob Agents Chemother 2015; 59:5697-704. [PMID: 26149989 DOI: 10.1128/aac.00690-15] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 06/29/2015] [Indexed: 11/20/2022] Open
Abstract
Previously, we demonstrated that a single prophylactic dose of SR-2P, a novel dual-component microbicide gel comprising acyclovir and tenofovir, led to a modest increase in mouse survival following a lethal challenge of herpes simplex virus 2 (HSV-2). Here, we show that a dose of SR-2P administered 24 h prior to infection provides some protection against the virus, but to a lesser degree than SR-2P administered either once a day for 2 days or 1 h prior to infection. None of the prophylactic doses blocked infection by the virus, and all resulted in 80 to 100% lethality. However, given that a prophylactic dose still provided a significant reduction in overall clinical score, reduced rate of body weight loss, and increased median survival of the mice, we examined whether a repetitive dose regimen (postinfection) in addition to the prophylactic dose could prevent death and reduce the levels of virus in mice. Nearly all (9 of 10 in each group) of the mice that received SR-2P for 2 days prior to infection or that received SR-2P 1 h prior to infection and were administered SR-2P once a day for 10 days after infection showed no clinical symptoms of infection and no viral loads in vaginal swabs and survived for 28 days postinfection. Conversely, mice receiving no treatment or an identical vehicle treatment demonstrated advanced clinical signs and did not survive past day 9 postinfection. We conclude that SR-2P is an effective anti-HSV-2 agent in mice.
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Srinivasan P, Dinh C, Zhang J, Pau CP, McNicholl JM, Lo Y, Herold BC, Teller R, Kiser P, Smith JM. Pharmacokinetic evaluation of tenofovir disoproxil fumarate released from an intravaginal ring in pigtailed macaques after 6 months of continuous use. J Med Primatol 2015; 43:364-9. [PMID: 25379594 DOI: 10.1111/jmp.12119] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND AND METHODS A reservoir intravaginal ring (IVR) eluting tenofovir disoproxil fumarate (TDF) was evaluated for 6 months of continuous use in normally cycling female pigtailed macaques with monthly IVR exchanges to define pharmacokinetics and safety. RESULTS AND CONCLUSIONS Tenofovir levels in vaginal secretions and tissue remained consistent for 6 months with no adverse safety concerns.
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Lack of in vitro–in vivo correlation for a UC781-releasing vaginal ring in macaques. Drug Deliv Transl Res 2015; 5:27-37. [DOI: 10.1007/s13346-015-0216-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Li X, Zhang L, Tian Y, Song Y, Zhan P, Liu X. Novel HIV-1 non-nucleoside reverse transcriptase inhibitors: a patent review (2011 – 2014). Expert Opin Ther Pat 2014; 24:1199-227. [DOI: 10.1517/13543776.2014.964685] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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28
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Loksha YM, Pedersen EB, Loddo R, Sanna G, Collu G, Giliberti G, Colla PL. Synthesis of Novel Fluoro Analogues of MKC442 as Microbicides. J Med Chem 2014; 57:5169-78. [DOI: 10.1021/jm500139a] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yasser M. Loksha
- Nucleic
Acid Center, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
- Faculty
of Pharmacy and Pharmaceutical Industries, Sinai University, Al-Arish, North Sinai, Egypt
| | - Erik B. Pedersen
- Nucleic
Acid Center, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Roberta Loddo
- Dipartimento
di Scienze Biomediche, Università di Cagliari, Cittadella Universitaria, 09042 Monserrato, Cagliari, Italy
| | - Giuseppina Sanna
- Dipartimento
di Scienze Biomediche, Università di Cagliari, Cittadella Universitaria, 09042 Monserrato, Cagliari, Italy
| | - Gabriella Collu
- Dipartimento
di Scienze Biomediche, Università di Cagliari, Cittadella Universitaria, 09042 Monserrato, Cagliari, Italy
| | - Gabriele Giliberti
- Dipartimento
di Scienze Biomediche, Università di Cagliari, Cittadella Universitaria, 09042 Monserrato, Cagliari, Italy
| | - Paolo La Colla
- Dipartimento
di Scienze Biomediche, Università di Cagliari, Cittadella Universitaria, 09042 Monserrato, Cagliari, Italy
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Murphy DJ, Desjardins D, Dereuddre-Bosquet N, Brochard P, Perrot L, Pruvost A, Le Grand R, Lagatie O, Vanhooren L, Feyaerts M, van Roey J, Malcolm RK. Pre-clinical development of a combination microbicide vaginal ring containing dapivirine and darunavir. J Antimicrob Chemother 2014; 69:2477-88. [PMID: 24862093 DOI: 10.1093/jac/dku160] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES Combination microbicide vaginal rings may be more effective than single microbicide rings at reducing/preventing sexual transmission of HIV. Here, we report the pre-clinical development and macaque pharmacokinetics of matrix-type silicone elastomer vaginal rings containing dapivirine and darunavir. METHODS Macaque rings containing 25 mg dapivirine, 100 mg dapivirine, 300 mg darunavir or 100 mg dapivirine+300 mg darunavir were manufactured and characterized by differential scanning calorimetry. In vitro release was assessed into isopropanol/water and simulated vaginal fluid. Macaque vaginal fluid and blood serum concentrations for both antiretrovirals were measured during 28 day ring use. Tissue levels were measured on day 28. Ex vivo challenge studies were performed on vaginal fluid samples and IC50 values were calculated. RESULTS Darunavir caused a concentration-dependent reduction in the dapivirine melting temperature in both solid drug mixes and in the combination ring. In vitro release from rings was dependent on drug loading, the number of drugs present and the release medium. In macaques, serum concentrations of both microbicides were maintained between 10(1) and 10(2) pg/mL. Vaginal fluid levels ranged between 10(3) and 10(4) ng/g and between 10(4) and 10(5) ng/g for dapivirine and darunavir, respectively. Both dapivirine and darunavir showed very similar concentrations in each tissue type; the range of drug tissue concentrations followed the general rank order: vagina (1.8 × 10(3)-3.8 × 10(3) ng/g) > cervix (9.4 × 10(1)-3.9 × 10(2) ng/g) > uterus (0-108 ng/g) > rectum (0-40 ng/g). Measured IC50 values were >2 ng/mL for both compounds. CONCLUSIONS Based on these results, and in light of recent clinical progress of the 25 mg dapivirine ring, a combination vaginal ring containing dapivirine and darunavir is a viable second-generation HIV microbicide candidate.
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Affiliation(s)
| | - Delphine Desjardins
- CEA, Division of Immuno-Virology, DSV/iMETI, IDMIT Center, 18 route du Panorama, F92265 Fontenay-aux-Roses, France UMR-E1, Paris Sud University-11, Orsay, France
| | - Nathalie Dereuddre-Bosquet
- CEA, Division of Immuno-Virology, DSV/iMETI, IDMIT Center, 18 route du Panorama, F92265 Fontenay-aux-Roses, France UMR-E1, Paris Sud University-11, Orsay, France
| | - Patricia Brochard
- CEA, Division of Immuno-Virology, DSV/iMETI, IDMIT Center, 18 route du Panorama, F92265 Fontenay-aux-Roses, France UMR-E1, Paris Sud University-11, Orsay, France
| | - Ludivine Perrot
- CEA, Division of Immuno-Virology, DSV/iMETI, IDMIT Center, 18 route du Panorama, F92265 Fontenay-aux-Roses, France UMR-E1, Paris Sud University-11, Orsay, France
| | - Alain Pruvost
- Commissariat à l'Energie Atomique, iBiTecS, SPI, Laboratoire d'Etude du Métabolisme des Médicaments, F-91191 Gif-sur-Yvette, France
| | - Roger Le Grand
- CEA, Division of Immuno-Virology, DSV/iMETI, IDMIT Center, 18 route du Panorama, F92265 Fontenay-aux-Roses, France UMR-E1, Paris Sud University-11, Orsay, France
| | - Ole Lagatie
- Janssen Diagnostics, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Leen Vanhooren
- Janssen Diagnostics, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Maxim Feyaerts
- Janssen Diagnostics, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Jens van Roey
- Janssen Diagnostics, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - R Karl Malcolm
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK
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30
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Forbes CJ, McCoy CF, Murphy DJ, Woolfson AD, Moore JP, Evans A, Shattock RJ, Malcolm RK. Modified silicone elastomer vaginal gels for sustained release of antiretroviral HIV microbicides. J Pharm Sci 2014; 103:1422-32. [PMID: 24585370 DOI: 10.1002/jps.23913] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 01/31/2014] [Accepted: 02/07/2014] [Indexed: 12/13/2022]
Abstract
We previously reported nonaqueous silicone elastomer gels (SEGs) for sustained vaginal administration of the CCR5-targeted entry inhibitor maraviroc (MVC). Here, we describe chemically modified SEGs (h-SEGs) in which the hydrophobic cyclomethicone component was partially replaced with relatively hydrophilic silanol-terminated polydimethylsiloxanes (st-PDMS). MVC and emtricitabine (a nucleoside reverse transcriptase inhibitor), both currently under evaluation as topical microbicides to counter sexual transmission of human immunodeficiency virus type 1 (HIV-1), were used as model antiretroviral (ARV) drugs. Gel viscosity and in vitro ARV release were significantly influenced by st-PDMS molecular weight and concentration in the h-SEGs. Unexpectedly, gels prepared with lower molecular weight grades of st-PDMS showed higher viscosities. h-SEGs provided enhanced release over 24 h compared with aqueous hydroxyethylcellulose (HEC) gels, did not modify the pH of simulated vaginal fluid (SVF), and were shown to less cytotoxic than standard HEC vaginal gel. ARV solubility increased as st-PDMS molecular weight decreased (i.e., as percentage hydroxyl content increased), helping to explain the in vitro release trends. Dye ingression and SVF dilution studies confirmed the increased hydrophilicity of the h-SEGs. h-SEGs have potential for use in vaginal drug delivery, particularly for ARV-based HIV-1 microbicides.
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Affiliation(s)
- Claire J Forbes
- School of Pharmacy, Queen's University Belfast, Belfast, BT9 7BL, UK
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31
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Abstract
PURPOSE OF REVIEW Early studies have cast doubt on the utility of animal models for predicting success or failure of HIV-prevention strategies, but results of multiple human phase 3 microbicide trials, and interrogations into the discrepancies between human and animal model trials, indicate that animal models were, and are, predictive of safety and efficacy of microbicide candidates. RECENT FINDINGS Recent studies have shown that topically applied vaginal gels, and oral prophylaxis using single or combination antiretrovirals are indeed effective in preventing sexual HIV transmission in humans, and all of these successes were predicted in animal models. Further, prior discrepancies between animal and human results are finally being deciphered as inadequacies in study design in the model, or quite often, noncompliance in human trials, the latter being increasingly recognized as a major problem in human microbicide trials. SUMMARY Successful microbicide studies in humans have validated results in animal models, and several ongoing studies are further investigating questions of tissue distribution, duration of efficacy, and continued safety with repeated application of these, and other promising microbicide candidates in both murine and nonhuman primate models. Now that we finally have positive correlations with prevention strategies and protection from HIV transmission, we can retrospectively validate animal models for their ability to predict these results, and more importantly, prospectively use these models to select and advance even safer, more effective, and importantly, more durable microbicide candidates into human trials.
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32
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Intravaginal ring eluting tenofovir disoproxil fumarate completely protects macaques from multiple vaginal simian-HIV challenges. Proc Natl Acad Sci U S A 2013; 110:16145-50. [PMID: 24043812 DOI: 10.1073/pnas.1311355110] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Topical preexposure prophylaxis interrupts HIV transmission at the site of mucosal exposure. Intermittently dosed vaginal gels containing the HIV-1 reverse transcriptase inhibitor tenofovir protected pigtailed macaques depending on the timing of viral challenge relative to gel application. However, modest or no protection was observed in clinical trials. Intravaginal rings (IVRs) may improve efficacy by providing long-term sustained drug delivery leading to constant mucosal antiretroviral concentrations and enhancing adherence. Although a few IVRs have entered the clinical pipeline, 100% efficacy in a repeated macaque vaginal challenge model has not been achieved. Here we describe a reservoir IVR technology that delivers the tenofovir prodrug tenofovir disoproxil fumarate (TDF) continuously over 28 d. With four monthly ring changes in this repeated challenge model, TDF IVRs generated reproducible and protective drug levels. All TDF IVR-treated macaques (n = 6) remained seronegative and simian-HIV RNA negative after 16 weekly vaginal exposures to 50 tissue culture infectious dose SHIV162p3. In contrast, 11/12 control macaques became infected, with a median of four exposures assuming an eclipse of 7 d from infection to virus RNA detection. Protection was associated with tenofovir levels in vaginal fluid [mean 1.8 × 10(5) ng/mL (range 1.1 × 10(4) to 6.6 × 10(5) ng/mL)] and ex vivo antiviral activity of cervicovaginal lavage samples. These observations support further advancement of TDF IVRs as well as the concept that extended duration drug delivery devices delivering topical antiretrovirals could be effective tools in preventing the sexual transmission of HIV in humans.
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Ariën KK, Venkatraj M, Michiels J, Joossens J, Vereecken K, Van der Veken P, Abdellati S, Cuylaerts V, Crucitti T, Heyndrickx L, Heeres J, Augustyns K, Lewi PJ, Vanham G. Diaryltriazine non-nucleoside reverse transcriptase inhibitors are potent candidates for pre-exposure prophylaxis in the prevention of sexual HIV transmission. J Antimicrob Chemother 2013; 68:2038-47. [DOI: 10.1093/jac/dkt166] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
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34
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Malcolm RK, Fetherston SM, McCoy CF, Boyd P, Major I. Vaginal rings for delivery of HIV microbicides. Int J Womens Health 2012. [PMID: 23204872 PMCID: PMC3508658 DOI: 10.2147/ijwh.s36282] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Following the successful development of long-acting steroid-releasing vaginal ring devices for the treatment of menopausal symptoms and contraception, there is now considerable interest in applying similar devices to the controlled release of microbicides against HIV. In this review article, the vaginal ring concept is first considered within the wider context of the early advances in controlled-release technology, before describing the various types of ring device available today. The remainder of the article highlights the key developments in HIV microbicide-releasing vaginal rings, with a particular focus on the dapivirine ring that is presently in late-stage clinical testing.
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Affiliation(s)
- R Karl Malcolm
- School of Pharmacy, Queen's University Belfast, Belfast, UK
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