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1.
Afr J AIDS Res ; 20(4): 277-286, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34905456

RESUMO

South African youth are one of the highest risk groups, globally, for HIV acquisition. Identifying prevention methods that will be acceptable and used consistently is an urgent priority. Engaging youth as co-designers is a targeted strategy to achieve the goal of developing prevention products that meet youth's needs. The iPrevent study engaged male and female youth, aged 18-24 years, in Cape Town, South Africa, to co-design critical aspects of the research project aimed at understanding youth preferences for long-acting pre-exposure prophylaxis (PrEP). An established advisory board of young men who have sex with men, women who have sex with men and men-who-have-sex-with-men, as well as a purposively selected youth cohort were involved in film-making, survey design and interpretation of study results. Convening youth as co-designers had several impacts on iPrevent's approach and outputs. Youth input informed the use of local actors in the study's educational video, creating a "real-world" community setting that meaningfully situated the content. Their participation led to the successful development of survey language and images to explain scientific concepts in terms that would resonate (e.g. chili peppers to express product-associated pain). Lastly, their insight reviewing results led to clarifications around misinterpretations of risk perception and confirmed youth's desires for products that fit into their goals around family, future happiness and education. The engagement of youth through creative, interactive activities contributed to adaptations of the study design, research implementation and understanding of results. This was important for connecting with young end-users and translating study findings for product developers in a way that reflected the context of their lives.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Profilaxia Pré-Exposição , Minorias Sexuais e de Gênero , Adolescente , Fármacos Anti-HIV/uso terapêutico , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Masculino , África do Sul
2.
Front Glob Womens Health ; 2: 684694, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34816231

RESUMO

Introduction: This study explored implant user and healthcare provider experiences of accessing and providing contraceptive implant removal services in Gaborone, Botswana, following introduction of the implant in the public sector in 2016. We sought to understand reasons for satisfaction and dissatisfaction with services and their potential impact on wider perceptions of the implant, including influence on future uptake. Methods: Qualitative data were collected through in-depth interviews. Participants comprised ten women who had previously undergone implant removal, and ten providers whose work included provision of implant insertion and removal. Data were analyzed using thematic content analysis. Results: Seven of the ten users in this study had experienced a delay between initial request and undergoing implant removal. This interval ranged from <1 week to 3 months. Users identified the principal barriers to accessing implant removal services as lack of access to trained removal providers, inconvenient appointment times, and provider resistance to performing removal. Nine of the ten providers in this study had experienced barriers to providing implant removal, including insufficient training, lack of equipment, lack of time, and lack of a referral pathway for difficult removals. Despite experiencing barriers in accessing removal, users' perceptions of the implant remained generally positive. Providers were concerned that ongoing negative user experiences of removal services would damage wider perceptions of the implant. Conclusion: Introduction of the contraceptive implant in Botswana has been an important strategy in increasing contraceptive choice. Following an initial focus on provision of insertion services, the development of comparable, accessible removal services is critical to ensuring that the implant remains a desirable contraceptive option and is vital to upholding women's reproductive health rights. The experiences of users and providers in this study can inform the ongoing development of services for implant insertion and removal in Botswana and other lower-resource settings.

3.
Sex Reprod Health Matters ; 29(1): 1927477, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34224341

RESUMO

ABSTRACTUnintended pregnancy and unmet need for modern contraception contribute substantially to reproductive health disparities globally. In sub-Saharan Africa they occur in contexts of disproportionately high rates of HIV infection. Multipurpose prevention technologies (MPTs) can address HIV and pregnancy prevention needs in a single "2-in-1" product; however, few studies have solicited end-user views to inform design of new MPTs. We conducted the Tablets, Ring, Injections as Options (TRIO) study with young women aged 18-30 in Kenya and South Africa (N = 277) to examine preferences and acceptability of future MPTs. In a randomised clinical cross-over study in which women used three placebo delivery forms, we complemented quantitative acceptability assessments with in-depth interviews and focus group discussions (N = 88 participants). We examined anticipated enablers and barriers to adoption and use of future MPTs and synthesised novel product design recommendations. Participants expressed high interest in MPTs. Anticipated side effects constituted a primary concern; however, many expected barriers were not dosage form-specific, but addressed contextual factors instead, such as fears regarding use of new biomedical technologies, misunderstandings and stigma regarding use, and navigating partner disclosure and engagement. Women preferred MPTs that offered discreetness and long-duration protection to minimise user-burden, did not interfere with their relationships, and conferred protection for unanticipated situations. End-user research to identify and pre-emptively address potential barriers while underscoring benefits to a new MPT product is vital. Attention to cultural contexts in implementation of new MPTs is important to communicating perceived benefits, achieving acceptability and maximising public health benefits.


Assuntos
Infecções por HIV , Anticoncepção , Estudos Cross-Over , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Quênia , Gravidez , África do Sul
4.
Afr J AIDS Res ; 20(1): 53-60, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33632073

RESUMO

Background: Men play a key role in influencing uptake of women's health products, such as female condoms and vaginal microbicides used for family planning and HIV prevention.Method: We explored men's perceptions of the dapivirine vaginal ring (DVR), a vaginal microbicide, in Kalungu District, rural south-western Uganda. In June/July 2018, we conducted in-depth interviews with 10 partners of women participating in the DREAM study, a phase 3B open-label extension trial of the DVR. Data were analysed thematically, drawing on the socio-ecological model theoretical framework.Results: Influencing factors such as individual and interpersonal characteristics, perception of HIV risk, lack of knowledge about the DVR, misconceptions, and product characteristics acting at different levels (individual, societal and organisational) affected men's knowledge, attitudes and perceptions towards the DVR, which in turn impacted on their willingness to allow their partners to use it. Above all, men wanted to be involved in the decision- making process about the use of the DVR. All the men were happy that there was a new HIV prevention option in the pipeline and were not concerned about the degree of effectiveness, saying it was better than nothing.Conclusion: The use of the DVR in an environment where men expect to make decisions about sex on behalf of women may affect its usage and success. Given this context, women may not always be able to independently choose to use it. If the DVR is approved and rolled out, increased sensitisation of men about it will be critical to ensure its uptake.


Assuntos
Dispositivos Anticoncepcionais Femininos , Infecções por HIV/prevenção & controle , Pirimidinas/administração & dosagem , Adolescente , Adulto , Feminino , Humanos , Masculino , Casamento , Pessoa de Meia-Idade , Adulto Jovem
5.
Cult Health Sex ; 23(3): 383-396, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32216584

RESUMO

Uptake of contraceptive implants has declined in South Africa since their introduction in 2014, with side effects and inadequate health provider training cited as primary contributors underlying a poor community perception of implants. In this paper we explore a theme that emerged unexpectedly during analysis of our research in Cape Town that may be an additional factor in this decline: narratives of women being assaulted by robbers who physically remove the implants for smoking as drugs. Narratives were described consistently across interviews and focus groups with youth (aged 18-24 years) and in interviews with health providers, with six participants (two young people, four health providers) sharing personal experiences of robbery. While there was a range of perspectives on whether narratives are based on real experiences or are myths, there was strong consensus that narratives of implant robbery may be influencing women's decisions around implant use in Cape Town. This is a potent example of how perceptions of new products can affect uptake and offers important lessons for implementers to reflect on in planning for rollout of other health technologies.


Assuntos
Anticoncepcionais , Narração , Adolescente , Feminino , Grupos Focais , Humanos , Percepção , África do Sul
7.
AIDS Patient Care STDS ; 33(4): 157-166, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30932697

RESUMO

Implants are in the pre-clinical stage for long-acting HIV pre-exposure prophylaxis (PrEP), with an opportunity to solicit end-users' feedback early in development. Health care providers (HCPs) have been key gatekeepers for contraceptive implant uptake, and uniquely understand both technical considerations and the social context of use. Given their influential role, we gathered South African HCP perspectives on contraceptive implant implementation and features of PrEP implant prototypes that may influence future provider and patient acceptability. We conducted in-depth interviews with 30 HCPs (20 nurses and 10 doctors) in Cape Town and Soshanguve, South Africa. Interviews were conducted by a bioengineer and later transcribed, coded, and analyzed for key themes. HCPs described health system barriers such as understaffed clinics and inadequate training on contraceptive implant removal as major influences to their PrEP implant design preferences. They preferred a PrEP implant that is long lasting (>6 months) to minimize patient-clinic interactions, biodegradable to avoid need for removal, and flexible (but still palpable in case of removal). Commenting on negative experiences with contraceptive implant rollout, they recommended prioritizing both HCP and community education on the PrEP implant, with emphasis on expected side effects, and planning ahead for adequate training of HCPs before rollout. Challenges experienced with past contraceptive implant rollout may taint perspectives on future PrEP implants and must be carefully considered during product development and planning for clinical studies. Particular consideration should be given to the health system context of future distribution, including staff who would be providing and monitoring implants.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Implantes de Medicamento , Infecções por HIV/prevenção & controle , Profilaxia Pré-Exposição/métodos , Adulto , População Negra , Feminino , Infecções por HIV/tratamento farmacológico , Pessoal de Saúde , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , África do Sul
8.
J Acquir Immune Defic Syndr ; 80(5): 542-550, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30865050

RESUMO

BACKGROUND: Long-acting injectable and implantable approaches aim to overcome some of the documented challenges with uptake and adherence to current HIV prevention methods. Youth are a key end-user population for these methods. We used qualitative methods to examine product attributes and preferences for current and future long-acting HIV prevention approaches. METHODS: Ninety-five South African youth aged 18-24 years, of whom 62 were female and 33 male, completed 50 interviews and 6 focus groups. We purposively selected for previous product experience, including oral pre-exposure prophylaxis, injectable pre-exposure prophylaxis, or the vaginal ring, to ensure participants' opinions were rooted in actual experience. RESULTS: Irrespective of previous method-use experience, gender, or sexual orientation, the majority expressed a preference for prevention methods formulated as injectables or implants. Several mentioned that their top priority in any product was efficacy, and for some, this overrode other concerns; for example, even if they feared pain, an implant or an injectable would be used if fully protective. Although efficacy was a top priority, there was also a clear desire across all subgroups for a product that would not interfere with sex, would stay in the system to provide protection, and that caused minimal burden, or was not apparent to others, and these characteristics were most salient for long-acting methods. CONCLUSIONS: Narrative explanations for preferences converged thematically around different dimensions of "invisibility" including invisibility to oneself, one's partner and household members, and community members. End-user preferences can be used to inform product development of long-acting HIV prevention approaches formulated as injections or implants to optimize adherence and impact.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/prevenção & controle , Preferência do Paciente , Profilaxia Pré-Exposição/métodos , Adolescente , Fármacos Anti-HIV/administração & dosagem , Preparações de Ação Retardada , Feminino , Humanos , Entrevistas como Assunto , Masculino , Preferência do Paciente/psicologia , África do Sul , Adulto Jovem
9.
PLoS One ; 13(10): e0204821, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30379839

RESUMO

BACKGROUND: HIV and pregnancy prevention are dual health priorities for women, and particularly in sub-Saharan Africa. Drug-eluting fibers offer a dosage form that combines HIV prevention and contraception, but early understanding of end-user perspectives is critical to avoid misalignment between products being developed and preferred product attributes. METHODS: Focus group discussions (FGDs) were conducted in South Africa, Uganda and Zimbabwe, among 55 women who had used vaginal products in previous trials. Participants were given the opportunity to feel a sample of electrospun nanofiber (the fabric), see how it dissolves, and give feedback on shape, size and other attributes. Women were also asked to compare the fabric to vaginal gel and film. RESULTS: Three key themes regarding the acceptability of the fabric emerged: 1) look and feel of the product undissolved vs. undissolved, 2) expected effect on sex, and 3) convenience and ease of use. Upon being presented with the fabric, women were initially distrustful, seeing it as undesirable for vaginal insertion. Women generally approved of the product once they saw it dissolve. However, they stressed the importance of the product not interfering with sex by altering the vaginal environment. Women also reacted favorably to the perceived convenience of the fabric, particularly with regards to storage and transport, perceived ease of insertion and use, and dosing regimen. CONCLUSION: Multipurpose prevention technologies, and nanofibers in particular, should be developed with an eye to minimizing impact on sex while maximizing convenience, and presented in such a way as to emphasize non-abrasiveness and ease of dissolution.


Assuntos
Anticoncepção/instrumentação , Infecções por HIV/prevenção & controle , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Preferência do Paciente/psicologia , Adulto , Anticoncepção/métodos , Feminino , Grupos Focais , Humanos , Nanofibras , Projetos Piloto , Pesquisa Qualitativa , África do Sul , Uganda , Cremes, Espumas e Géis Vaginais , Zimbábue
10.
J Int AIDS Soc ; 21(8): e25170, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30152004

RESUMO

INTRODUCTION: Implants are a new dosage form in development for HIV pre-exposure prophylaxis (PrEP) with potential for high adherence given that they are provider-administered and are intended for long-acting protection. Integrating end-user preference into early stage product development may further overcome challenges with future product uptake and adherence. Hence, we sought to optimize the design of a PrEP implant in early-stage development by gathering opinions about implant attributes from potential end-users in South Africa. METHODS: We conducted 14 focus group discussions (FGDs) with young women and men aged 18 to 24 in Cape Town and Soshanguve, South Africa, inviting participants into discussion as co-designers. FGDs were homogenous by gender and previous implant experience. During FGDs, we showed prototype devices and followed a semi-structured guide with questions on history of contraceptive implant use, preferences for physical characteristics of an implant, implant biodegradability, insertion process, participant-driven ideas for implant design, and social adoption considerations. FGDs were facilitated in English, isiXhosa, Tswana, isiZulu, or Tsonga, audio-recorded, transcribed into English, and qualitatively coded and analysed. RESULTS: In this qualitative sample of 105 youth (68 women and 37 men), 58 participants were from Soshanguve and 47 from Cape Town, and 23% had previously used contraceptive implants. Participants expressed preferences for several implant design features; specifically, longer duration (≥6 months) was more important to most participants than the size or number of devices implanted. A majority preferred a flexible versus stiff implant to minimize palpability, thereby increasing discreetness and comfort. Nearly all participants favoured a biodegradable implant to avoid removal and thus reduce clinic visits. Concerns about the implant centred on its possible side effects and the "plastic" look of the prototype displayed for demonstration. CONCLUSIONS: This study offers preliminary insights into an implant for HIV prevention that provides long-lasting protection may be well received among young South Africans. Additionally, flexibility, discreetness, and biodegradability may increase acceptability of the implant. Such end-user feedback is being incorporated into current implant designs in the hope of creating an effective long-acting PrEP product that is likely to achieve high uptake and adherence in target populations.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Implantes de Medicamento , Infecções por HIV/prevenção & controle , Adolescente , População Negra , Feminino , Grupos Focais , Humanos , Masculino , Profilaxia Pré-Exposição/métodos , Gravidez , África do Sul , Adulto Jovem
11.
Biomaterials ; 144: 1-16, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28802690

RESUMO

Current approaches for topical vaginal administration of nanoparticles result in poor retention and extensive leakage. To overcome these challenges, we developed a nanoparticle-releasing nanofiber delivery platform and evaluated its ability to improve nanoparticle retention in a murine model. We individually tailored two components of this drug delivery system for optimal interaction with mucus, designing (1) mucoadhesive fibers for better retention in the vaginal tract, and (2) PEGylated nanoparticles that diffuse quickly through mucus. We hypothesized that this novel dual-functioning (mucoadhesive/mucus-penetrating) composite material would provide enhanced retention of nanoparticles in the vaginal mucosa. Equivalent doses of fluorescent nanoparticles were vaginally administered to mice in either water (aqueous suspension) or fiber composites, and fluorescent content was quantified in cervicovaginal mucus and vaginal tissue at time points from 24 h to 7d. We also fabricated composite fibers containing etravirine-loaded nanoparticles and evaluated the pharmacokinetics over 7d. We found that our composite materials provided approximately 30-fold greater retention of nanoparticles in the reproductive tract at 24 h compared to aqueous suspensions. Compared to nanoparticles in aqueous suspension, the nanoparticles in fiber composites exhibited sustained and higher etravirine concentrations after 24 h and up to 7d, demonstrating the capabilities of this new delivery platform to sustain nanoparticle release out to 3d and drug retention out to one week after a single administration. This is the first report of nanoparticle-releasing fibers for vaginal drug delivery, as well as the first study of a single delivery system that combines two components uniquely engineered for complementary interactions with mucus.


Assuntos
Preparações de Ação Retardada/química , Corantes Fluorescentes/administração & dosagem , Nanofibras/química , Nanopartículas/administração & dosagem , Piridazinas/administração & dosagem , Inibidores da Transcriptase Reversa/administração & dosagem , Vagina/metabolismo , Administração Intravaginal , Animais , Sistemas de Liberação de Medicamentos/métodos , Feminino , Corantes Fluorescentes/farmacocinética , Camundongos , Camundongos Endogâmicos C57BL , Mucosa/metabolismo , Nanofibras/ultraestrutura , Nanopartículas/análise , Nitrilas , Piridazinas/farmacocinética , Pirimidinas , Inibidores da Transcriptase Reversa/farmacocinética
12.
Int J Pharm ; 475(1-2): 282-91, 2014 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-25169075

RESUMO

Electrospun fibers containing antiretroviral drugs have recently been investigated as a new dosage form for topical microbicides against HIV-1. However, little work has been done to evaluate the scalability of the fiber platform for pharmaceutical production of medical fabrics. Scalability and cost-effectiveness are essential criteria in developing fibers as a practical platform for use as a microbicide and for translation to clinical use. To address this critical gap in the development of fiber-based vaginal dosage forms, we assessed the scale-up potential of drug-eluting fibers delivering tenofovir (TFV), a nucleotide reverse transcriptase inhibitor and lead compound for topical HIV-1 chemoprophylaxis. Here we describe the process of free-surface electrospinning to scale up production of TFV fibers, and evaluate key attributes of the finished products such as fiber morphology, drug crystallinity, and drug loading and release kinetics. Poly(vinyl alcohol) (PVA) containing up to 60 wt% TFV was successfully electrospun into fibers using a nozzle-free production-scale electrospinning instrument. Actual TFV loading in fibers increased with increasing weight percent TFV in solution, and encapsulation efficiency was improved by maintaining TFV solubility and preventing drug sedimentation during batch processing. These results define important solution and processing parameters for scale-up production of TFV drug-eluting fibers by wire electrospinning, which may have significant implications for pharmaceutical manufacturing of fiber-based medical fabrics for clinical use.


Assuntos
Adenina/análogos & derivados , Organofosfonatos/administração & dosagem , Organofosfonatos/química , Cloreto de Polivinila/química , Vagina/efeitos dos fármacos , Adenina/administração & dosagem , Adenina/química , Administração Intravaginal , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/química , Formas de Dosagem , Sistemas de Liberação de Medicamentos/métodos , Feminino , HIV-1/efeitos dos fármacos , Humanos , Inibidores da Transcriptase Reversa/administração & dosagem , Inibidores da Transcriptase Reversa/química , Tenofovir
13.
Int J Nanomedicine ; 9: 2967-78, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24971008

RESUMO

BACKGROUND: Electrospun drug-eluting fabrics have enormous potential for the delivery of physicochemically diverse drugs in combination by controlling the underlying material chemistry and fabric microarchitecture. However, the rationale for formulating drugs at high drug loading in the same or separate fibers is unknown but has important implications for product development and clinical applications. METHODS: Using a production-scale free-surface electrospinning instrument, we produced electrospun nanofibers with different microscale geometries for the co-delivery of tenofovir (TFV) and levonorgestrel (LNG) - two lead drug candidates for multipurpose prevention of HIV acquisition and unintended pregnancy. We investigated the in vitro drug release of TFV and LNG combinations from composites that deliver the two drugs from the same fiber (combined fibers) or from separate fibers in a stacked or interwoven architecture. For stacked composites, we also examined the role that fabric thickness has on drug-release kinetics. We also measured the cytotoxicity and antiviral activity of the drugs delivered alone and in combination. RESULTS: Herein, we report on the solution and processing parameters for the free-surface electrospinning of medical fabrics with controlled microarchitecture and high drug loading (up to 20 wt%). We observed that in vitro release of the highly water-soluble TFV, but not the water-insoluble LNG, was affected by composite microarchitecture, fabric thickness, and drug content. Finally, we showed that the drug-loaded nanofibers are noncytotoxic and that the antiviral activity of TFV is preserved through the electrospinning process and when combined with LNG. CONCLUSION: Electrospun fabrics with high drug loading create multicomponent systems that benefit from the independent control of the nanofibrous microarchitecture. Our findings are significant because they will inform the design and production of composite electrospun fabrics for the co-delivery of physicochemically diverse drugs that may be useful for multipurpose prevention.


Assuntos
Adenina/análogos & derivados , Sobrevivência Celular/efeitos dos fármacos , Galvanoplastia/métodos , HIV-1/efeitos dos fármacos , Levanogestrel/administração & dosagem , Nanofibras/administração & dosagem , Nanofibras/química , Organofosfonatos/administração & dosagem , Adenina/administração & dosagem , Adenina/química , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/química , Anticoncepcionais Femininos/administração & dosagem , Anticoncepcionais Femininos/química , Difusão , Combinação de Medicamentos , Desenho de Fármacos , Células HeLa , Humanos , Levanogestrel/química , Nanocompostos/administração & dosagem , Nanocompostos/química , Nanocompostos/ultraestrutura , Nanofibras/ultraestrutura , Organofosfonatos/química , Rotação , Tenofovir
14.
Antiviral Res ; 100 Suppl: S9-16, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24188701

RESUMO

Diversity of microbicide delivery systems is essential for future success in the prevention and treatment of HIV in order to account for the varied populations of women all over the world that may benefit from use of these products. Recently, a novel dosage form for intravaginal drug delivery has been developed using drug-eluting fibers fabricated by electrospinning. There is a strong rationale to support the idea that drug-eluting fibers can be designed to realize multiple design constraints in a single product for topical HIV prevention: fibers are able to deliver a wide range of agents, incorporate multiple agents via composites, and facilitate controlled release over relevant time frames for pericoital and sustained (coitally-independent) use. It is also technologically feasible to scale-up production of fiber-based microbicides. Electrospun fibers may allow for prioritization of physical attributes that affect user perceptions without compromising biological efficacy. Challenges with using fibers as a microbicide include issues related to vehicle deployment, spreading and retention in the vaginal vault. In addition, studies will need to address the interaction of the fibers with the mucosal environment, including unknown safety and toxicity. Sustained release fiber microbicides capable of delivering multiple antiretroviral drugs while simultaneously exhibiting tunable degradation or dissolution of the fibers is also a challenge. However, electrospun fibers are a promising new platform for vaginal delivery of anti-HIV agents and future research will inform their place in the field. This article is based on a presentation at the "Product Development Workshop 2013: HIV and Multipurpose Prevention Technologies", held in Arlington, Virginia on February 20-21, 2013. It forms part of a special supplement to Antiviral Research.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Sistemas de Liberação de Medicamentos/instrumentação , Infecções por HIV/prevenção & controle , HIV-1/efeitos dos fármacos , Administração Intravaginal , Sistemas de Liberação de Medicamentos/métodos , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV-1/fisiologia , Humanos
15.
PLoS One ; 8(4): e61416, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23630586

RESUMO

BACKGROUND: The use of drug combinations has revolutionized the treatment of HIV but there is no equivalent combination product that exists for prevention, particularly for topical HIV prevention. Strategies to combine chemically incompatible agents may facilitate the discovery of unique drug-drug activities, particularly unexplored combination drug synergy. We fabricated two types of nanoparticles, each loaded with a single antiretroviral (ARV) that acts on a specific step of the viral replication cycle. Here we show unique combination drug activities mediated by our polymeric delivery systems when combined with free tenofovir (TFV). METHODOLOGY/PRINCIPAL FINDINGS: Biodegradable poly(lactide-co-glycolide) nanoparticles loaded with efavirenz (NP-EFV) or saquinavir (NP-SQV) were individually prepared by emulsion or nanoprecipitation techniques. Nanoparticles had reproducible size (d ∼200 nm) and zeta potential (-25 mV). The drug loading of the nanoparticles was approximately 7% (w/w). NP-EFV and NP-SQV were nontoxic to TZM-bl cells and ectocervical explants. Both NP-EFV and NP-SQV exhibited potent protection against HIV-1 BaL infection in vitro. The HIV inhibitory effect of nanoparticle formulated ARVs showed up to a 50-fold reduction in the 50% inhibitory concentration (IC50) compared to free drug. To quantify the activity arising from delivery of drug combinations, we calculated combination indices (CI) according to the median-effect principle. NP-EFV combined with free TFV demonstrated strong synergistic effects (CI50 = 0.07) at a 1∶50 ratio of IC50 values and additive effects (CI50 = 1.05) at a 1∶1 ratio of IC50 values. TFV combined with NP-SQV at a 1∶1 ratio of IC50 values also showed strong synergy (CI50 = 0.07). CONCLUSIONS: ARVs with different physicochemical properties can be encapsulated individually into nanoparticles to potently inhibit HIV. Our findings demonstrate for the first time that combining TFV with either NP-EFV or NP-SQV results in pronounced combination drug effects, and emphasize the potential of nanoparticles for the realization of unique drug-drug activities.


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/farmacologia , Benzoxazinas/farmacologia , Infecções por HIV/prevenção & controle , Nanopartículas/química , Organofosfonatos/farmacologia , Saquinavir/farmacologia , Adenina/farmacologia , Adenina/toxicidade , Alcinos , Animais , Fármacos Anti-HIV/toxicidade , Benzoxazinas/toxicidade , Linhagem Celular , Colo do Útero/efeitos dos fármacos , Química Farmacêutica , Ciclopropanos , Preparações de Ação Retardada/farmacologia , Preparações de Ação Retardada/toxicidade , Portadores de Fármacos/farmacologia , Portadores de Fármacos/toxicidade , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , HIV-1/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Ácido Láctico/química , Macaca , Modelos Biológicos , Nanopartículas/toxicidade , Organofosfonatos/toxicidade , Tamanho da Partícula , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Saquinavir/toxicidade , Espectroscopia de Infravermelho com Transformada de Fourier , Tenofovir , Técnicas de Cultura de Tecidos
16.
PLoS One ; 7(11): e49792, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23209601

RESUMO

Multipurpose prevention technologies (MPTs) that simultaneously prevent sexually transmitted infections (STIs) and unintended pregnancy are a global health priority. Combining chemical and physical barriers offers the greatest potential to design effective MPTs, but integrating both functional modalities into a single device has been challenging. Here we show that drug-eluting fiber meshes designed for topical drug delivery can function as a combination chemical and physical barrier MPT. Using FDA-approved polymers, we fabricated nanofiber meshes with tunable fiber size and controlled degradation kinetics that facilitate simultaneous release of multiple agents against HIV-1, HSV-2, and sperm. We observed that drug-loaded meshes inhibited HIV-1 infection in vitro and physically obstructed sperm penetration. Furthermore, we report on a previously unknown activity of glycerol monolaurate (GML) to potently inhibit sperm motility and viability. The application of drug-eluting nanofibers for HIV-1 prevention and sperm inhibition may serve as an innovative platform technology for drug delivery to the lower female reproductive tract.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Anticoncepção , Anticoncepcionais/administração & dosagem , HIV-1/efeitos dos fármacos , Nanofibras/química , Animais , Fármacos Anti-HIV/química , Anticoncepcionais/química , Sistemas de Liberação de Medicamentos , Feminino , Infecções por HIV/prevenção & controle , Humanos , Lauratos/farmacologia , Macaca , Masculino , Camundongos , Monoglicerídeos/farmacologia , Nanofibras/ultraestrutura , Gravidez , Infecções Sexualmente Transmissíveis/prevenção & controle , Espermatozoides/efeitos dos fármacos
17.
J Control Release ; 142(2): 229-37, 2010 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-19874858

RESUMO

The development of safe and efficient polymer carriers for DNA vaccine delivery requires mechanistic understanding of structure-function relationship of the polymer carriers and their interaction with antigen-presenting cells. Here we have synthesized a series of diblock copolymers with well-defined chain-length using atom transfer radical polymerization and characterized the influence of polycation chain-length on the physico-chemical properties of the polymer/DNA complexes as well as the interaction with dendritic cells. The copolymers consist of a hydrophilic poly(ethylene glycol) block and a cationic poly(aminoethyl methacrylate) (PAEM) block. The average degree of polymerization (DP) of the PAEM block was varied among 19, 39, and 75, with nearly uniform distribution. With increasing PAEM chain-length, polyplexes formed by the diblock copolymers and plasmid DNA had smaller average particle size and showed higher stability against electrostatic destabilization by salt and heparin. The polymers were not toxic to mouse dendritic cells (DCs) and only displayed chain-length-dependent toxicity at a high concentration (1mg/mL). In vitro gene transfection efficiency and polyplex uptake in DCs were also found to correlate with chain-length of the PAEM block with the longer polymer chain favoring transfection and cellular uptake. The polyplexes induced a modest up-regulation of surface markers for DC maturation that was not significantly dependent on PAEM chain-length. Finally, the polyplex prepared from the longest PAEM block (DP of 75) achieved an average of 20% enhancement over non-condensed anionic dextran in terms of uptake by DCs in the draining lymph nodes 24h after subcutaneous injection into mice. Insights gained from studying such structurally well-defined polymer carriers and their interaction with dendritic cells may contribute to improved design of practically useful DNA vaccine delivery systems.


Assuntos
Resinas Acrílicas/química , DNA/administração & dosagem , Células Dendríticas/metabolismo , Polietilenoglicóis/química , Transfecção , Resinas Acrílicas/síntese química , Animais , Linhagem Celular , Permeabilidade da Membrana Celular , Sobrevivência Celular , Células Cultivadas , DNA/genética , Células Dendríticas/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Polietilenoglicóis/síntese química
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