Pre-exposure Prophylaxis Strategies Research Articles

HIV-1 Integrase T218I/S Polymorphisms Do Not Reduce HIV-1 Integrase Inhibitors' Phenotypic Susceptibility.

The recently Food and Drug Administration (FDA)-approved cabotegravir (CAB) has demonstrated efficacy as an antiretroviral agent for HIV treatment and prevention, becoming an important tool to stop the epidemic in the United States of America (USA). However, the effectiveness of CAB can be compromised by the presence of specific integrase natural polymorphisms, including T97A, L74M, M50I, S119P, and E157Q, particularly when coupled with the primary drug-resistance mutations G140S and Q148H. CAB's recent approval as a pre-exposure prophylaxis (PrEP) may increase the number of individuals taking CAB, which, at the same time, could increase the number of epidemiological implications. In this context, where resistance mutations, natural polymorphisms, and the lack of drug-susceptibility studies prevail, it becomes imperative to comprehensively investigate concerns related to the use of CAB. We used molecular and cell-based assays to assess the impact of T218I and T218S in the context of major resistance mutations G140S/Q148H on infectivity, integration, and resistance to CAB. Our findings revealed that T218I and T218S, either individually or in combination with G140S/Q148H, did not significantly affect infectivity, integration, or resistance to CAB. Notably, these polymorphisms also exhibited neutrality concerning other widely used integrase inhibitors, namely raltegravir, elvitegravir, and dolutegravir. Thus, our study suggests that the T218I and T218S natural polymorphisms are unlikely to undermine the effectiveness of CAB as a treatment and PrEP strategy.

Phylogenetic Network Analyses Reveal the Influence of Transmission Clustering on the Spread of HIV Drug Resistance in Quebec from 2002 to 2022.

HIV drug resistance (HIV-DR) may jeopardize the benefit of antiretroviral therapy (ART) in treatment and prevention. This study utilized viral phylogenetics to resolve the influence of transmission networks on sustaining the spread of HIV-DR in Quebec spanning 2002 to 2022. Time trends in acquired (ADR) and transmitted drug resistance (TDR) were delineated in treatment-experienced (n = 3500) and ART-naïve persons (n = 6011) with subtype B infections. Similarly, non-B-subtype HIV-DR networks were assessed pre- (n = 1577) and post-ART experience (n = 488). Risks of acquisition of resistance-associated mutations (RAMs) were related to clustering using 1, 2-5, vs. 6+ members per cluster as categorical variables. Despite steady declines in treatment failure and ADR since 2007, rates of TDR among newly infected, ART-naive persons remained at 14% spanning the 2007-2011, 2012-2016, and 2017-2022 periods. Notably, half of new infections among men having sex with men and heterosexual groups were linked in large, clustered networks having a median of 35 (14-73 IQR) and 16 (9-26 IQR) members per cluster, respectively. Cluster membership and size were implicated in forward transmission of non-nucleoside reverse transcriptase inhibitor NNRTI RAMs (9%) and thymidine analogue mutations (TAMs) (5%). In contrast, transmission of M184V, K65R, and integrase inhibitors (1-2%) remained rare. Levels of TDR reflected viral replicative fitness. The median baseline viremia in ART-naïve groups having no RAMs, NNRTI RAMs, TAMs, and M184VI were 46.088, 38,447, 20,330, and 6811 copies/mL, respectively (p < 0.0001). Phylogenetics emphasize the need to prioritize ART and pre-exposure prophylaxis strategies to avert the expansion of transmission cascades of HIV-DR.

Cost-effectiveness of different intervention strategies of human immunodeficiency virus in Zhejiang, China: a Model Study From 2023 to 2052.

:Mass screening for human immunodeficiency virus (HIV) and preexposure prophylaxis (PrEP) may be effective measures for reducing the probability of HIV transmission. Our study aimed to determine the cost-effectiveness of preliminary screening in the general population, PrEP for HIV-negative spouses in serodiscordant couples, or both approaches in Zhejiang Province. :From a policy-maker's perspective, a Markov model was constructed to compare 4 strategies over a 30-year horizon. :In the Markov model, the implementation intensities of the strategies varied from 50% to 100%. Different strategies were evaluated by the reduction of unfavorable clinical outcomes, saved life-years (LYs), quality-adjusted life-years (QALYs), incremental cost-effectiveness ratios (ICERs), and net monetary benefits (NMBs). :The PrEP-Screening strategy reduced the most unfavorable clinical outcomes and saved the most LYs and QALYs from 2023 to 2052. It always gained the maximum QALYs and NMB, while its ICER was always lower than the willingness-to-pay (WTP). The NMB of the PrEP-Screening strategy gradually increased as the implementation intensity increased. :With adequate manpower and policies, we suggest implementing the PrEP-Screening strategy in Zhejiang Province, suggesting that the broader the population coverage of the strategy, the better. In addition, the PrEP strategy is an alternative.

Identifying priority groups for pre-exposure prophylaxis among sex workers in Flanders, Belgium: insights into routine HIV and sexually transmitted infection data in community-based clinics

ObjectivesThe burden of HIV and other sexually transmitted infections (STIs) remains high in sex workers globally, calling for strengthening targeted prevention strategies, including HIV pre-exposure prophylaxis (PrEP). The study’s objective...

The Global Impact of Diversifying PrEP Options: Results of an International Discrete Choice Experiment of Existing and Potential PrEP Strategies with Gay and Bisexual Men and Physicians.

To improve current and future use of existing (oral, injectable) and potential future (implants, douches) pre-exposure prophylaxis (PrEP) products, we must understand product preferences relative to one another, among gay and bisexual men (GBM), and physicians who prescribe PrEP. We completed an online discrete choice experiment (DCE) with separate groups of GBM and/or physicians from the United States, South Africa, Spain, and Thailand. Participants were presented information on PrEP products, including daily pills, event-driven pills (2-1-1 regimen), injections, subdermal implants (dissolvable, removable), and rectal douches. Next, they completed a choice exercise in which they were shown 10 screens, each presenting 3 of the aforementioned products at a time with 11 attributes for physicians and 10 attributes for GBM. For the attributes that were not constant, one level was shown per screen for each product. Participants selected the product they preferred most and rated their likelihood to select (GBM) or recommend (physicians) that product. Data were modeled using hierarchical Bayes estimation; resulting model coefficients were used to develop attribute importance measures and product preferences. For GBM across all countries, if all aforementioned PrEP products were on the market at the same time, over 90% of GBM would use some form of PrEP; 100% of physicians would recommend at least one of the PrEP products. There were variations in product preference by country. GBM in the United States and Thailand preferred the injection (21.7%, 22.9%, respectively), while the dissolvable implant was preferred in South Africa and Spain (19.9%, 19.8%, respectively). In the United States, South Africa, and Spain (where physician data were available), physicians were most likely to recommend the dissolvable implant (37.2%, 40.6%, 38.3%, respectively).

Navigating patterns of oral PrEP use: A qualitative longitudinal study of gay, bisexual, and queer men's dynamic practices of pausing, on-demand, and stopping PrEP in Canada

The Canadian HIV pre-exposure prophylaxis (PrEP) guidelines recommend both daily and on-demand dosing for gay, bisexual, and queer men (GBQM), meeting additional risk criteria. However, limited research explored how GBQM implement pausing, on-demand, discontinuation, and resumption of PrEP, including the contextual factors affecting decision-making. Using a relationally situated implementation science framework, we examined how GBQM tailor PrEP use to changing social and sexual circumstances. We conducted 109 longitudinal interviews with current and former PrEP users from Ontario (n = 18) and British Columbia (n = 20), Canada, at three time points between 2020 and 2022. We identified three dynamic PrEP use trajectories: pausing, on-demand, and stopping. Pausing involved brief breaks followed by a return to daily use during heightened sexual activity. Others followed the 2-1-1 on-demand schedule, while some stopped PrEP with plans to resume if social and sexual circumstances change. During the COVID-19 pandemic, participants paused PrEP when sexual activities decreased, restarting daily use when sexual engagements resumed. Others paused due to relationship changes or sexual inactivity, resuming PrEP in anticipation of sex. On-demand PrEP was adopted to manage side effects or save costs. Some stopped PrEP for sustained periods due to monogamy, private insurance loss, side effects, or low perceived HIV risk. Participants expressed concerns regarding lack of information on these strategies, relying on online sources or peers for guidance. Most participants obtained enough PrEP knowledge to adapt use appropriately. Comprehensive education campaigns on adaptable PrEP use effectiveness and strategies to discontinue and resume PrEP for clinicians and GBQM should be implemented.

Awareness and willingness to use pre-exposure prophylaxis for HIV prevention among men who have sex with men in Rwanda: findings from a web-based survey.

Pre-exposure Prophylaxis (PrEP) is a daily pill aimed at reducing HIV transmission risk when taken as prescribed. It's highly recommended for high-risk Men who have sex with Men (MSM). This study aimed to assess PrEP awareness and willingness to use it among Rwandan MSM, a critical aspect given PrEP's proven effectiveness. The findings are expected to inform policy decisions and further advance the implementation of PrEP strategies. This is a cross-sectional study design that utilized a web-based survey conducted between April and June 2019 to assess awareness and willingness to use PrEP among sexually active MSM in Rwanda. A snowball sampling technique was used to recruit participants via social media such as WhatsApp and e-mail. Eligibility criteria included being sexually active, aged ≥18 years, self-identifying as MSM, residing in Rwanda, self-reported engagement in receptive or insertive anal sex in the last 12 months, and self-reported HIV-negative serostatus. We assessed two primary outcomes: PrEP awareness (having ever heard of PrEP) and willingness to use PrEP within one month of completing the survey. Multivariable logistic regression was performed to identify participant characteristics associated with PrEP awareness and willingness to use it. Out of 521 participants, the majority (73%) demonstrated awareness of PrEP. Factors linked to PrEP awareness included residing outside the capital, Kigali, being in the 18-29 age group, having higher education levels, perceiving a benefit from PrEP, and engaging in vaginal sex with a woman while using a condom in the last year. Additionally, 96% of participants expressed a strong willingness to use PrEP. Rwandan MSM exhibits a high level of PrEP awareness, notably associated with factors like location, age, education, perceived benefits, and condom use. The study also revealed a strong willingness to use PrEP, indicating promising prospects for its adoption among this group. These findings highlight the need for targeted awareness campaigns, personalized interventions, and comprehensive sexual health education to promote PrEP adoption and strengthen HIV prevention efforts among Rwandan MSM.

A pilot program of HIV pre-exposure prophylaxis in Thai youth.

There are gaps in knowledge and experience of antiretroviral pre-exposure prophylaxis (PrEP) delivery in adolescents. This pilot study enrolled Thai adolescents 14-20 year-old without HIV who reported risk behaviour. All participants were offered daily tenofovir/emtricitabine (TDF-FTC) and followed for 24 weeks. HIV testing, renal function, bone density scan, and sexually transmitted infection (STI) testing including syphilis serology and urine molecular testing for gonorrhoea and C. trachomatis were performed at baseline and weeks 12 and 24. Adherence was evaluated through intracellular tenofovir diphosphate (TFV-DP) levels in dried blood spots. Of the 61 enrolled adolescents, median age 18.1 (IQR: 14.8-20.9) years, 46 (75.4%) were males and 36 (59%) were MSM. Retention to week 24 was 80.3%. One third (36%) had TFV-DP levels consistent with taking ≥6 pills/week at week 12 and 29% at week 24. The factors associated with taking ≥6 pills/week were being MSM (adjusted odds ratio [aOR]: 53.2, 95% CI: 1.6-1811; p = 0.027), presence of STI at baseline (aOR: 9.4, 95% CI: 1.5-58.5; p = 0.016), and self-report of decreased condom use while taking PrEP (aOR: 8.7, 95% CI: 1.4-56.6; p = 0.023). 31% had an STI at baseline and this declined to 18% at week 24. No renal or bone toxicity was observed and there were no HIV seroconversions. Daily oral PrEP with FTC-TDF in high-risk Thai adolescents is feasible, accepted, well-tolerated, and had no increased risk compensation; however, low adherence was a major challenge. Adolescent-specific PrEP strategies including long-acting modalities are needed for successful HIV prevention.

COVID-19 Outcomes in Lung Transplant Recipients Following Pre-Exposure Prophylaxis With Tixagevimab-Cilgavimab During the Omicron BA.5 Surge: A Single Center Analysis.

Lung transplant (LTx) recipients are at high risk for COVID-19 related morbidity and mortality. Data regarding pre-exposure prophylaxis (PrEP) with tixagevimab-cilgavimab in this population are scarce. We therefore evaluated COVID-19 breakthrough infections and COVID-19 related complications after PrEP in a retrospective single-center study, including 264 LTx recipients who received PrEP between June 2022 and December 2022, when Omicron BA.5 was the dominant circulating SARS-CoV-2 variant. PrEP was indicated for fully vaccinated patients with poor seroconversion (anti-S <260BAU/mL). COVID-19 breakthrough infection after PrEP occurred in 11.0% within the first 3months, increasing to 17.4% within 6months. Hospitalization rate rose from 27.6% to 52.9% (p = 0.046), while ICU admissions and COVID-19 mortality remained low, respectively occurring in 6.5% and 4.3% of patients with breakthrough infection within 6months. COVID-19 breakthrough infection and associated hospitalization remained an important problem during the Omicron BA.5 surge in fully vaccinated LTx recipients with deficient seroconversion, despite PrEP with tixagevimab-cilgavimab. However, ICU admissions and COVID-19 mortality were low. Waning of neutralizing effects of PrEP and changing circulating SARS-CoV-2 variants may explain increases in COVID-19 infections and hospitalizations over time after PrEP, highlighting the need for novel, long-term effective PrEP strategies in these high-risk patients.

Evolution of Humoral and Cellular Immunity Post-Breakthrough Coronavirus Disease 2019 in Vaccinated Patients With Hematologic Malignancy Receiving Tixagevimab-Cilgavimab.

In-depth immunogenicity studies of tixagevimab-cilgavimab (T-C) are lacking, including following breakthrough coronavirus disease 2019 (COVID-19) in vaccinated patients with hematologic malignancy (HM) receiving T-C as pre-exposure prophylaxis. We performed a prospective, observational cohort study and detailed immunological analyses of 93 patients with HM who received T-C from May 2022, with and without breakthrough infection, during a follow-up period of 6 months and dominant Omicron BA.5 variant. In 93 patients who received T-C, there was an increase in Omicron BA.4/5 receptor-binding domain (RBD) immunoglobulin G (IgG) antibody titers that persisted for 6 months and was equivalent to 3-dose-vaccinated uninfected healthy controls at 1 month postinjection. Omicron BA.4/5 neutralizing antibody was lower in patients receiving B-cell-depleting therapy within 12 months despite receipt of T-C. COVID-19 vaccination during T-C treatment did not incrementally improve RBD or neutralizing antibody levels. In 16 patients with predominantly mild breakthrough infection, no change in serum neutralization of Omicron BA.4/5 postinfection was detected. Activation-induced marker assay revealed an increase in CD4+ (but not CD8+) T cells post infection, comparable to previously infected healthy controls. Our study provides proof-of-principle for a pre-exposure prophylaxis strategy and highlights the importance of humoral and cellular immunity post-breakthrough COVID-19 in vaccinated patients with HM.

The effect of combination prevention strategies on HIV incidence among gay and bisexual men who have sex with men in the UK: a model-based analysis

In the UK, the number of new HIV diagnoses among gay and bisexual men who have sex with men (GBMSM) has decreased substantially. We aimed to understand the contribution of different interventions in reducing HIV incidence so far; to estimate future HIV incidence with continuation of current policies and with further scaling up of current interventions; and to estimate the maximum additional annual cost that should be spent towards these interventions for them to offer value for money. We calibrated a dynamic, individual-based, stochastic simulation model, the HIV Synthesis Model, to multiple sources of data on HIV among GBMSM aged 15 years or older in the UK. Primarily these were routine HIV surveillance data collected by the UK Health Security Agency. We compared HIV incidence in 2022 with the counterfactual incidence: if HIV testing rates stopped increasing in 2012 and the policy of antiretroviral therapy (ART) at diagnosis was not introduced in mid-2015; if pre-exposure prophylaxis (PrEP) was not introduced; if condom use was low from 2012 in all GBMSM, at levels similar to those observed in 1980; and in the first and second scenario combined. We also projected future outcomes under the assumption of continuation of current policies and considering increases in PrEP and HIV testing uptake and a decrease in condomless sex. Our model estimated a 77% (90% uncertainty interval [UI] 61-88) decline in HIV incidence since around 2014, with an estimated 597 infections ([90% UI 312-956]; 1·1 per 1000 person-years [90% UI 0·6-1·8]) in men aged 15-64 years in 2022. Both PrEP introduction and increased HIV testing with ART initiation at diagnosis each had a substantial effect on HIV incidence. Without PrEP introduction, we estimate there would have been 2·16 times the number of infections that actually occurred (90% UI 1·06-3·75) between 2012 and 2022; without increased HIV testing and ART initiation at diagnosis there would have been 2·18 times the number of infections that actually occurred (1·18-3·60), and if condomless sex was at the levels before the HIV epidemic, there would have been 2·27 times the number of infections that actually occurred (0·9-5·4). If rates of testing, ART use, and PrEP use remain as they are currently, there is a predicted decline in incidence to 388 HIV infections in 2025 (90% UI 226-650) and to 263 (137-433) in 2030. Increases in HIV testing and PrEP use were predicted to accelerate the decline in HIV incidence. Given the quality-adjusted life-year (QALY) benefit and a cost-effectiveness threshold of £30 000 per QALY gained, in order to be cost-effective an additional £1·62 million could be spent per year to increase testing levels by 34% (90% UI 25-46) and PrEP use by 55% (10-107). To achieve that, a 16% reduction in the cost of delivery of testing and PrEP would be required. Combination prevention, including a PrEP strategy, played a major role in the reduction in HIV incidence observed so far in the UK among GBMSM. Continuation of current activities should lead to a continued decline; however, it is unlikely to lead to reaching the target of fewer than 50 HIV infections per year among GBMSM by 2030. It will be important to reduce costs for testing and PrEP for their continued expansion to be cost-effective. National Institute for Health Research under its Programme Grants for Applied Research Programme and Medical Research Council-UK Research and Innovation.

Prevalence of HIV in Kazakhstan 2010-2020 and Its Forecasting for the Next 10 Years.

HIV is a growing public health burden that threatens thousands of people in Kazakhstan. Countries around the world, including Kazakhstan, are facing significant problems in predicting HIV infection prevalence. It is crucial to understand the epidemiological trends of infectious diseases and to monitor the prevalence of HIV in a long-term perspective. Thus, in this study, we aimed to forecast the prevalence of HIV in Kazakhstan for 10 years from 2020 to 2030 by using mathematical modeling and time series analysis. We use statistical Autoregressive Integrated Moving Average (ARIMA) models and a nonlinear epidemic Susceptible-Infected (SI) model to forecast the HIV infection prevalence rate in Kazakhstan. We estimated the parameters of the models using open data on the prevalence of HIV infection among women and men (aged 15-49 years) in Kazakhstan provided by the Kazakhstan Bureau of National Statistics. We also predict the effect of pre-exposure prophylaxis (PrEP) control measures on the prevalence rate. The ARIMA (1,2,0) model suggests that the prevalence of HIV infection in Kazakhstan will increase from 0.29 in 2021 to 0.47 by 2030. On the other hand, the SI model suggests that this parameter will increase to 0.60 by 2030 based on the same data. Both models were statistically significant by Akaike Information Criterion corrected (AICc) score and by the goodness of fit. HIV prevention under the PrEP strategy on the SI model showed a significant effect on the reduction of the HIV prevalence rate. This study revealed that ARIMA (1,2,0) predicts a linear increasing trend, while SI forecasts a nonlinear increase with a higher prevalence of HIV. Therefore, it is recommended for healthcare providers and policymakers use this model to calculate the cost required for the regional allocation of healthcare resources. Moreover, this model can be used for planning effective healthcare treatments.

The Use of Daily and On-Demand Oral Pre-Exposure Prophylaxis Dosing Strategies Among Young Adult Gay, Bisexual and Other Men who have Sex with Men Enrolled in an mHealth Adherence Intervention.

Pre-exposure prophylaxis (PrEP) is a highly effective HIV prevention option for gay, bisexual and other men who have sex with men (GBMSM). However, with newer PrEP options, a greater understanding of whether and why GBMSM switch dosing strategies is needed to inform clinical practice and research. We assessed the dosing strategies (daily or on-demand) of GBMSM enrolled in an mHealth PrEP adherence pilot intervention at four timepoints over approximately 10 months. Among GBMSM with complete data (n = 66), a consistent daily dosing strategy was used by most (73%) participants across all time points, while on-demand PrEP was used at least once during the study period by 27% of participants. A higher percentage of on-demand PrEP users self-reported as Asian/Pacific Islander and had less positive attitudes toward PrEP, adjusting for key sociodemographic variables and intervention arm. Daily PrEP users reported high numbers of sexual partners, and the primary reason that they would switch to on-demand PrEP is reduced sexual activity. At the final assessment, 75% of participants were taking daily PrEP, of whom 27% reported that they would like to switch to another option, including on-demand and long-acting injectable PrEP. While findings were largely descriptive, they showed that switches in PrEP dosing strategies are relatively common and PrEP strategy choice may vary across racial and ethnic groups.

Overcoming structural barriers to diffusion of HIV pre-exposure prophylaxis.

HIV prevention with antiretroviral medication in the form of pre-exposure prophylaxis (PrEP) offers a critical tool to halt the HIV pandemic. Barriers to PrEP access across drug types, formulations, and delivery systems share remarkable commonalities and are likely to be generalizable to future novel PrEP strategies. Appreciation of these barriers allows for planning earlier in the drug-development pathway rather than waiting for the demonstration of efficacy. The purpose of this article is to propose a core set of considerations that should be included in the drug-development process for future PrEP interventions. A literature synthesis of key barriers to PrEP uptake in the United States was conducted to elucidate commonalities across PrEP agents and delivery methods. Based on the published literature, we divided challenges into three main categories of structural barriers: (1) provider and clinic characteristics; (2) cost considerations; and (3) disparities and social constructs, with potential solutions provided for each. Pragmatic strategies for examining and overcoming these barriers before future PrEP regulatory approval are recommended. If these strategies are considered well before the time of commercial availability, the potential for PrEP to interrupt the HIV pandemic will be greatly enhanced.

A Cost-Effectiveness Analysis of Pre-Exposure Prophylaxis to Avert Rabies Deaths in School-Aged Children in India.

Children contribute to one-half of the total painful rabies mortalities in India. The state-of-the-art rabies mortality averting strategies need exploration for the effective implementation of pre-exposure prophylaxis (PrEP) in India. This study reports on the economic evaluation of various PrEP and post-exposure prophylaxis (PEP) strategies to avert rabies mortalities in school-aged children in India. A decision tree model has been developed for children in the age group of 5-15 years to evaluate various PrEP + PEP and PEP only regimens. The 2-site intradermal regimen administered on day zero and seven was chosen as the intervention [PrEP (I)]. ICER was calculated from the quasi-societal and quasi-health systems' perspectives for the base case analysis, along with one-way sensitivity, and scenario analyses for each regimen. The incremental DALYs averted per million population with the implementation of PrEP (I) ranged between 451 and 85,069 in 2020. The ICER was reported in the range of USD 384-352/DALY averted (non-dominant) in comparison to PEP regimens from a quasi-societal perspective. PrEP (I) is reported to be 'very cost effective' in comparison with PEP regimens from the quasi-societal and quasi-health systems' perspectives and reduce deaths by up to 89.9%. This study concludes that the PrEP (I) regimen is a cost-effective and life-saving strategy to avert painful mortalities due to rabies in school-aged children in India.

Using nominal group technique to identify barriers and facilitators to preventing HIV using combination same-day pre-exposure prophylaxis and medications for opioid use disorder

BackgroundPreventing HIV transmission among people who inject drugs (PWID) is a key element of the US Ending the HIV Epidemic strategy and includes both pre-exposure prophylaxis (PrEP) and medications for opioid use disorder (MOUD). While both lead to decreases in HIV transmission, MOUD has other social and health benefits; meanwhile, PrEP has additional HIV prevention advantages from sexual risk and the injection of stimulants. However, these medications are often prescribed in different settings and require multiple visits before initiation. Strategies to integrate these services (i.e., co-prescription) and offer same-day prescriptions may reduce demands on patients who could benefit from them.MethodsNominal group technique, a consensus method that rapidly generates and ranks responses, was used to ascertain barriers and solutions for same-day delivery of PrEP and MOUD as an integrated approach among PWID (n = 14) and clinical (n = 9) stakeholders. The qualitative portion of the discussion generated themes for analysis, and the ranks of the proposed barriers and solutions to the program are presented.ResultsThe top three barriers among PWID to getting a same-day prescription for both PrEP and MOUD were (1) instability of insurance (e.g., insurance lapses); (2) access to a local prescriber; and (3) client-level implementation factors, such as lack of personal motivation. Among clinical stakeholders, the three greatest challenges were (1) time constraints on providers; (2) logistics (e.g., coordination between providers and labs); and (3) availability of providers who can prescribe both medications. Potential solutions identified by both stakeholders included pharmacy delivery of the medications, coordinated care between providers and health care systems (e.g., case management), and efficiencies in clinical care (e.g., clinical checklists), among others.ConclusionsImplementing and sustaining a combined PrEP and MOUD strategy will require co-training providers on both medications while creating efficiencies in systems of care and innovations that encourage and retain PWID in care. Pilot testing the co-prescribing of PrEP and MOUD with quality performance improvement is a step toward new practice models.

Factors associated with long-term HIV pre-exposure prophylaxis engagement and adherence among transgender women in Brazil, Mexico and Peru: results from the ImPrEP study.

IntroductionThe HIV epidemic continues to disproportionately impact Latin‐American transgender women (TGW). We assessed factors associated with long‐term pre‐exposure prophylaxis (PrEP) engagement and adherence among TGW enrolled in the Implementation of PrEP (ImPrEP) study, the largest PrEP demonstration study in Latin America.MethodsHIV‐negative TGW aged ≥18 years reporting 1+eligibility criteria in the 6 months prior to enrolment (e.g. sex partner known to be living with HIV, condomless anal sex [CAS], transactional sex or having a sexually transmitted infection [STI]) who could safely take PrEP were enrolled. Follow‐up visits were conducted at 4 weeks and then quarterly. We conducted logistic regression to identify factors associated with long‐term PrEP engagement (3+ follow‐up visits in 52 weeks) and complete self‐reported adherence (no missed pills in the past 30 days) during follow‐up. For both outcomes, we constructed multivariable models controlling for country, socio‐demographics, sexual behaviour, substance use, STIs and self‐reported adherence at 4 weeks (long‐term engagement outcome only).ResultsFrom March 2018 to June 2021, ImPrEP screened 519 TGW, enrolled 494 (Brazil: 190, Mexico: 66 and Peru: 238) and followed them for 52 weeks. At baseline, 27.5% of TGW were aged 18–24 years, 67.8% were mixed‐race and 31.6% had >secondary education. Most, 89.9% reported CAS, 61.9% had >10 sex partners and 71.9% reported transactional sex. HIV incidence was 1.82 cases per 100 person‐years (95% confidence interval [CI]: 0.76–4.38). Almost half of TGW (48.6%) had long‐term PrEP engagement, which was positively associated with reporting complete adherence at week 4 (aOR:2.94 [95%CI:1.88–4.63]) and was inversely associated with reporting CAS with unknown‐HIV partner (aOR:0.52 [95%CI:0.34–0.81]), migration (aOR:0.54 [95%CI:0.34–0.84]), and being from Mexico (aOR:0.28 [95%CI:0.14–0.53]). Self‐reported adherence was associated with TGW aged >34 (aOR:1.61 [95%CI:1.10–2.34]) compared to those aged 25–34 and those with >secondary education (aOR:1.55 [95%CI:1.10–2.19]) and was lower among TGW from Peru (aOR:0.29 [95%CI:0.21–0.41]) or reporting PrEP‐related adverse effects (aOR:0.63 [95%CI:0.42–0.92]).ConclusionsAlthough TGW were willing to enrol in ImPrEP, long‐term PrEP engagement and complete self‐reported adherence were limited, and HIV incidence remained relatively high. A successful HIV prevention agenda should include trans‐specific interventions supporting oral PrEP and exploring long‐acting PrEP strategies for TGW.

SARS-CoV-2 pre-exposure prophylaxis: A potential COVID-19 preventive strategy for high-risk populations, including healthcare workers, immunodeficient individuals, and poor vaccine responders.

The unprecedented worldwide spread of SARS-CoV-2 has imposed severe challenges on global health care systems. The roll-out and widespread administration of COVID-19 vaccines has been deemed a major milestone in the race to restrict the severity of the infection. Vaccines have as yet not entirely suppressed the relentless progression of the pandemic, due mainly to the emergence of new virus variants, and also secondary to the waning of protective antibody titers over time. Encouragingly, an increasing number of antiviral drugs, such as remdesivir and the newly developed drug combination, Paxlovid® (nirmatrelvir/ritonavir), as well as molnupiravir, have shown significant benefits for COVID-19 patient outcomes. Pre-exposure prophylaxis (PrEP) has been proven to be an effective preventive strategy in high-risk uninfected people exposed to HIV. Building on knowledge from what is already known about the use of PrEP for HIV disease, and from recently gleaned knowledge of antivirals used against COVID-19, we propose that SARS-CoV-2 PrEP, using specific antiviral and adjuvant drugs against SARS-CoV-2, may represent a novel preventive strategy for high-risk populations, including healthcare workers, immunodeficient individuals, and poor vaccine responders. Herein, we critically review the risk factors for severe COVID-19 and discuss PrEP strategies against SARS-CoV-2. In addition, we outline details of candidate anti-SARS-CoV-2 PrEP drugs, thus creating a framework with respect to the development of alternative and/or complementary strategies to prevent COVID-19, and contributing to the global armamentarium that has been developed to limit SARS-CoV-2 infection, severity, and transmission.

Implementation of an HIV Pre-exposure Prophylaxis Strategy Into Abortion and Early Pregnancy Loss Care.

Family planning and abortion clinics routinely address sexual health. We sought to evaluate implementation outcomes of an HIV pre-exposure prophylaxis (PrEP) care strategy for patients seeking management of induced abortion and pregnancy loss. Single-center, urban, academic, hospital-based family planning service. We used a multifaceted implementation strategy directed toward family planning providers comprised of educational sessions, an electronic medical record-prompted verbal assessment of HIV risk, electronic medical record shortcuts for PrEP prescription, and support of a PrEP navigator. We assessed penetration of the intervention by calculating the penetration of a PrEP offer, measured as the proportion of encounters in which PrEP was offered to PrEP-eligible individuals. We evaluated feasibility, acceptability, and appropriateness of the intervention using belief elicitation interviews with providers. From November 2018 to April 2019, the proportion of PrEP eligible patients who were offered PrEP, was 87.9% (29/33). Providers found the intervention acceptable and appropriate, but reported barriers including time constraints, and disappointment if patients did not adhere to PrEP. Providers liked that PrEP provision in abortion care settings felt innovative, and that they could contribute to HIV prevention. Family planning providers in an academic center found HIV risk assessment and PrEP provision to be feasible, acceptable, and appropriate. Further research should evaluate implementation outcomes of PrEP care strategies in additional abortion care contexts, including clinics offering reproductive health care outside of academia.

The predictive value of macaque models of preexposure prophylaxis for HIV prevention.

We review macaque models for preexposure prophylaxis (PrEP) for HIV prevention and highlight their role in advancing currently approved and novel PrEP agents. The development of the repeat low dose simian HIV (SHIV) challenge models represented a significant advancement in preclinical PrEP modeling that has allowed the investigation of PrEP under conditions that better mimic HIV exposures in humans. These models incorporate relevant drug pharmacology to inform drug correlates of PrEP protection. Models of rectal, vaginal, and penile infection are now available and have been found to predict clinical efficacy of all the currently approved PrEP strategies including daily oral PrEP with the combination of emtricitabine and tenofovir disoproxil fumarate or tenofovir alafenamide, and a long-acting formulation of the integrase inhibitor cabotegravir. These models are being used to test new PrEP modalities including the nucleoside reverse transcriptase-translocation inhibitor islatravir and long-acting capsid inhibitors. The SHIV models have also been supplemented by sexually transmitted infection co-infections with Chlamydia trachomatis, Treponema pallidum or Trichomonas vaginalis to assess the impact of inflammation on PrEP efficacy. Clinical efficacy validated current PrEP macaque models supporting their continued use to advance novel PrEP agents to improve global PrEP coverage.