Setting the stage for expanding HIV pre-exposure prophylaxis use in Canada.
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ABSTRACT:
SUBMITTER: Hull M
PROVIDER: S-EPMC5937069 | biostudies-literature | 2017 Dec
REPOSITORIES: biostudies-literature
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Setting the stage for expanding HIV pre-exposure prophylaxis use in Canada.
Canada communicable disease report = Releve des maladies transmissibles au Canada 20171207 12
Human immunodeficiency virus (HIV) infection continues to disproportionately affect vulnerable populations in Canada; particularly men who have sex with men (MSM). Novel HIV prevention strategies have recently expanded from the use of non-occupational post-exposure prophylaxis (nPEP) after high risk exposures to the use of pre-exposure prophylaxis (PrEP) in which individuals reduce risk of HIV infection through use of combination antiretrovirals taken prior to risk exposure. With approval of ten ...[more]
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Project description:Few studies of pre-exposure prophylaxis (PrEP) to prevent HIV infection have focused on drug users. Between February to September 2013, we asked 351 opiate injectors entering detoxification treatment about HIV risk, knowledge about PrEP, and willingness to use a once daily PrEP pill under one of two randomly assigned effectiveness scenarios-40 % (low) or 90 % (high) effective in reducing HIV risk. Participants were 70 % male and 87 % non-Hispanic White. Only 7 % had heard of a drug to reduce HIV risk, yet once informed, 47 % would be willing to take such a pill [35 % of those in the low effectiveness scenario and 58 % in the high group (p < 0.001)]. Higher perceived HIV risk was associated with greater willingness to take medication. Increasing knowledge of PrEP and the rate of HIV reduction-effectiveness promised will influence its use among targeted high-risk drug users.
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Project description:Pre-exposure prophylaxis (PrEP) has emerged as a promising strategy for preventing the transmission of HIV. Although only one formulation is currently approved for PrEP, research into both new compounds and new delivery systems for PrEP regimens offer intriguing challenges from the perspective of pharmacokinetic and pharmacodynamic modeling. This review aims to provide an overview the current modeling landscape for HIV PrEP, focused on PK/PD and QSP models relating to antiretroviral agents. Both current PrEP treatments and new compounds that show promise as PrEP agents are highlighted, as well as models of uncommon administration routes, predictions based on models of mechanism of action and viral dynamics, and issues related to adherence to therapy. The spread of human immunodeficiency virus (HIV) remains one of the foremost global health concerns. In the absence of a vaccine, other prophylactic strategies have been developed to prevent HIV transmission. One approach, known as pre-exposure prophylaxis (PrEP), allows HIV-negative individuals who are at high risk of exposure to the virus, be it through an HIV-positive sexual partner or through the shared use of drug injection equipment, to substantially reduce the risk of developing an HIV infection. PrEP is a relatively recent approach to combating the HIV epidemic, with the only currently approved treatment being Truvada, a daily oral antiretroviral (ARV) therapy initially indicated in the treatment of active HIV-1 infections, but approved for HIV PrEP in 2012. Although PrEP therapy has consistently demonstrated high efficacy in preventing HIV infection, this efficacy is dependent on patient adherence to the prescribed treatment regimen. This can present a significant problem in low- and middle-income countries, which may lack the infrastructure to provide sufficient access to PrEP medication to maintain daily dosing regimens. Furthermore, while the conventional approach has generally been to advocate for continuous administration akin to regimens used for viral suppression in infected patients, there has been some discussion of whether a better treatment paradigm might be to push for PrEP therapy primarily during those known periods of heightened exposure risk, while relying on post-exposure prophylaxis regimens to prevent infection after unanticipated exposures during low-risk periods. These considerations have led to a push for the development of long-duration and on-demand PrEP formulations, including subdermal and subcutaneous implants, slow-release intramuscular depot injections, vaginal and rectal antimicrobial gels, and intravaginal rings and dissolving films. PrEP therapy is a quickly evolving field, with a variety of antiretroviral compounds and formulations under investigation. This review aims to report on notable drugs and formulations from a pharmacokinetic/pharmacodynamic (PK/PD) modeling perspective. Given the nature of PrEP as a preventive therapy designed for long-term use, clinical trials for PrEP therapies can last for months or even years, particularly in the case of long-duration formulations. Furthermore, in contrast to antiretroviral trials in infected patients, pharmacodynamic endpoints in PrEP therapies are difficult to quantify, as the primary endpoint for efficacy is generally the rate of seroconversion. Computational modeling approaches offer flexible and powerful tools to provide insight into drug behavior in clinical settings, and can ultimately reduce the time, expense, and patient burden incurred in the development of PrEP therapies.
| S-EPMC7005100 | biostudies-literature
Project description:IntroductionSingle-tablet combination emtricitabine/tenofovir is highly effective as HIV pre-exposure prophylaxis (PrEP). Scale-up efforts have targeted men who have sex with men (MSM), but patterns of racial disparities in PrEP use have begun to emerge. African, Caribbean and Black (ACB) communities in Canada and USA are also disproportionately affected by HIV, and there is lack of guidance regarding PrEP implementation in this priority population.MethodsACB men from Toronto, Canada were recruited in community settings by peers. Participants completed a detailed socio-behavioural questionnaire. Biological samples were collected and tested for sexually transmitted infections. Willingness to accept PrEP was assessed in relation to actual and self-perceived risk of acquiring HIV, as well as demographic and behavioural variables.Results424 ACB men were included in the analysis. ACB MSM were more likely to accept PrEP than ACB men only reporting sex with women (MSW; 50.0% vs. 23.6%). The most common reasons for PrEP non-acceptance were concerns regarding side-effects and low self-perceived risk. PrEP acceptance was lowest among younger men (12.5%) and those born in Canada (15.2%). Men with a high self-perceived HIV risk were more likely to accept PrEP (41.3% vs. 22.7% of men with a low self-perceived risk), but only 25.4% of men who were defined as being at high-risk, self-identified themselves as such.ConclusionsMost ACB MSW were unlikely to accept PrEP, largely due to low self-perceived HIV risk, but PrEP acceptance among ACB MSM was similar to other contemporaneous Toronto MSM communities. PrEP acceptance was particularly low among younger ACB men and those born in Canada. Tailored strategies will be needed to effectively implement PrEP in Toronto ACB communities.
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Project description:Purpose: In Argentina, transgender women face a disproportionately high prevalence of HIV infection (34%). Although not currently approved in Argentina, pre-exposure prophylaxis (PrEP) may offer a potential effective HIV prevention tool for this population. In this study, we assessed the willingness to use PrEP among transgender women in Argentina. Methods: Data were drawn from a nationwide cross-sectional survey conducted among transgender women in 2013. Using multivariable logistic regression, we assessed the prevalence of and factors associated with willingness to use PrEP among transgender women with negative or unknown HIV status. Results: This study included 337 transgender women (278 HIV negative and 59 with unknown HIV status), most of whom had a history of sex work involvement (81.8%). Overall, 301 (89.3%) expressed willingness to use PrEP. In a multivariable analysis, having casual sexual partners was positively associated with willingness to use PrEP (adjusted odds ratio [AOR]=4.26, 95% confidence interval [CI] 1.73-10.51), while discrimination by healthcare workers was negatively associated (AOR=0.33, 95% CI 0.12-0.88). Conclusion: We found high levels of willingness to use PrEP among transgender women in Argentina, suggesting that there is high perception of HIV risk in this population. However, discrimination by healthcare workers was a strong negative correlate of willingness to use PrEP, suggesting that multilevel interventions that address gender-based stigma in healthcare settings will be critical for the success of PrEP as an HIV prevention strategy in this population.
| S-EPMC5367484 | biostudies-other
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Project description:Diversion of antiretroviral therapy (ART) for recreational use is concerning for countries with high HIV prevalence. This paper presents reports of recreational use of ART among adolescents from two HIV prevention studies in South Africa: (1) a cross-sectional survey of N = 200 adolescents and (2) a qualitative study of pre-exposure prophylaxis with N = 57 adolescents and N = 25 clinicians. Among adolescents, 3% used and 14% knew someone who used non-prescribed ART for recreational purposes. Administration included smoking (71%), snorting (15%), injecting (15%), ingesting (15%), and inserting (3%). Participants predicted increased crime as recreational use of ART increased. Future studies should investigate prevalence, composition, and diversion of ART from HIV prevention and treatment.
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Project description:BackgroundPre-exposure prophylaxis (PrEP) has the potential to reduce HIV transmission and stem the HIV epidemic. Unfortunately, PrEP uptake in rural sub-Saharan Africa has been slow and medication adherence has been suboptimal.ObjectiveTo explore the perspectives, attitudes, and experiences of HIV serodiscordant partners taking PrEP and develop a messaging campaign to improve PrEP uptake in rural Mozambique to reduce HIV transmission among serodiscordant partners.MethodsIn this qualitative study, we interviewed 20 people in serodiscordant relationships using PrEP at a rural health center in Zambézia province, Mozambique and employed inductive and deductive coding to elicit their perspectives, attitudes, and experiences related to learning their partner's HIV status, barriers to PrEP uptake, obstacles to PrEP adherence, and decisions to disclose their PrEP use with family and friends using thematic analysis.ResultsOur analysis generated nine themes across various levels of the socioecological model. Participants reported a strong desire to stay in the discordant relationship and highlighted the importance of working together to ensure PrEP and antiretroviral therapy adherence, with the majority skeptical that adherence could be achieved without both partners' support (individual and interpersonal). Although most participants were reticent about sharing their serodiscordant status with family and friends (individual and interpersonal), those who did found their family and friends supportive (interpersonal). Participants suggested increasing community health agent availability to help people navigate HIV prevention and treatment (organizational). We then created three oral stories, using themes from the interviews, with examples from various levels of the socioecological model that will be used to generate support for PrEP use among community members.ConclusionsOur findings informed oral template stories that will be used to emphasize how couples can work together to improve PrEP uptake and reduce incident HIV infections in serodiscordant couples elsewhere in rural Mozambique.
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Project description:There are several guidelines for the use of pre-exposure prophylaxis (PrEP) for human immunodeficiency virus (HIV) which are used in other countries. However, the implementation of such guidelines in each country should be modified according to the country's clinical and epidemiological situation. Therefore, The Korean Society for AIDS founded a committee in 2016 to develop guidelines for the use of PrEP for HIV that are optimal for Korea's clinical and epidemiological situation. These guidelines aim to provide comprehensive information for PrEP implementation in Korea. The recommendations contain important information for physicians working to prevent HIV infection in actual clinical fields. The committee will regularly review and revise the guidelines based on changes in PrEP administration and HIV prevention practices.
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Project description:HIV Pre-Exposure Prophylaxis (PrEP) has been found to be efficacious in preventing HIV acquisition among seronegative individuals in a variety of risk groups, including men who have sex with men and people who inject drugs. To date, however, it remains unclear how socio-cultural norms (e.g., attitudes towards HIV; social understandings regarding HIV risk practices) may influence the scalability of future PrEP interventions. The objective of this study is to assess how socio-cultural norms may influence the implementation and scalability of future HIV PrEP interventions in Vancouver, Canada.We conducted 50 interviews with young men (ages 18-24) with a variety of HIV risk behavioural profiles (e.g., young men who inject drugs; MSM). Interviews focused on participants' experiences and perceptions with various HIV interventions and policies, including PrEP.While awareness of PrEP was generally low, perceptions about the potential personal and public health gains associated with PrEP were interconnected with expressions of complex and sometimes conflicting social norms. Some accounts characterized PrEP as a convenient form of reliable protection against HIV, likening it to the female birth control pill. Other accounts cast PrEP as a means to facilitate 'socially unacceptable' behaviour (e.g., promiscuity). Stigmatizing rhetoric was used to position PrEP as a tool that could promote some groups' proclivities to take 'risks'.Stigma regarding 'risky' behaviour and PrEP should not be underestimated as a serious implementation challenge. Pre-implementation strategies that concomitantly aim to improve knowledge about PrEP, while addressing associated social prejudices, may be key to effective implementation and scale-up.
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