Long-acting injectable cabotegravir for the prevention of HIV infection

Peer Influence on Motivation to Use Pre-Exposure Prophylaxis Among Latino Sexual Minority Men in Miami, Florida: A Network Autocorrelation Model

Despite the availability of pre-exposure prophylaxis (PrEP), Latino sexual minority men (LSMM) continue to experience disparities in PrEP uptake and subsequently, HIV vulnerability. Social network norms are an underutilized solution to increase PrEP uptake. We used a peer influence model (network autocorrelation model) to examine the role of social network descriptive norms (i.e., actual behaviors) surrounding PrEP use. A total of 11 sociocentric networks of 13 friends (n = 143 LSMM) were recruited into our study from 2018 to 2019 in South Florida. Most participants were in PrEP pre-contemplation (n = 44), and almost one-third of our sample were using PrEP (n = 38). Three network autocorrelation models were estimated using an empirically informed Bayesian analysis. We found a positive association between participants' Motivational PrEP Cascade (MPC) position and their network members' (friends') cascade position based on three different measures of connection even when accounting for PrEP knowledge: friendship (ρ = 0.22; 95% CIa = 0.01-0.42), emotional closeness (ρ = 0.24; 95% CI = 0.03-0.44), and frequency of interaction (ρ = 0.22; CI = 0.03-0.42). Our findings highlight that an individual's progress in the MPC may be influenced by their network members' progress in the MPC, suggesting that LSMM using PrEP may serve as role models to their peers for PrEP use due to descriptive norms. Our findings further suggest that PrEP interventions for LSMM along the MPC can be implemented at the social network level.

Identification of Determinants and Implementation Strategies to Increase Long-Acting Injectable PrEP for HIV Prevention Among Latino Men Who Have Sex with Men (MSM)

BACKGROUND

Latino men who have sex with men (LMSM) are disproportionally affected by HIV infections in the USA. The uptake rate of pre-exposure prophylaxis (PrEP) for HIV prevention has remained low among LMSM. Long-acting injectable PrEP (LAI-PrEP) may have the potential to improve structural, behavioral, and cognitive barriers to adherence. Given the potential benefits of LAI-PrEP and the limited data with this population, the aim of our study was to explore experiences and attitudes of LAI-PrEP among LMSM and identify implementation barriers compared to the standard oral presentation, align proposed implementation strategies, and propose outcomes to monitor and assess impact.

METHODS

In this qualitative study, guided by the Consolidated Framework for Implementation Research, we explored health care providers perspectives on facilitators and barriers to LAI-PrEP implementation strategies for LMSM. Interviews were recorded, transcribed, and analyzed using thematic content analysis.

RESULTS

Fear of immigration policies, ability to conceal PrEP medication, health insurance coverage, health information fatigue, lack of culturally adapted information, and provider's lack of knowledge were among the main barriers to LAI-PrEP. Most providers discussed the need for adapted and/or tailored training materials for and suggested designing marketing materials and specific clinical recommendations for LAI-PrEP.

CONCLUSION

In order to ensure an effective adaptation process that encompasses local and national goals of HIV prevention, future interventions should be designed in a way that incorporates culturally relevant information for LMSM. This study provides an implementation research logic model to guide future studies.

Current status of the small molecule anti-HIV drugs in the pipeline or recently approved

Human Immunodeficiency Virus (HIV) is the causative agent of Acquired Immunodeficiency Syndrome (AIDS) with high morbidity and mortality rates. Treatment of AIDS/HIV is being complicated by increasing resistance to currently used antiretroviral (ARV) drugs, mainly in low- and middle-income countries (LMICs) due to drug misuse, poor drug supply and poor treatment monitoring. However, progress has been made in the development of new ARV drugs, targeting different HIV components (Fig. 1). This review aims at presenting and discussing the progress made towards the discovery of new ARVs that are at different stages of clinical trials as of July 2024. For each compound, the mechanism of action, target biomolecule, genes associated with resistance, efficacy and safety, class, and phase of clinical trial are discussed. These compounds include analogues of nucleoside reverse transcriptase inhibitors (NRTIs) - islatravir and censavudine; non-nucleoside reverse transcriptase inhibitors (NNRTIs) - Rilpivirine, elsulfavirine and doravirine; integrase inhibitors namely cabotegravir and dolutegravir and chemokine coreceptors 5 and 2 (CC5/CCR2) antagonists for example cenicriviroc. Also, fostemsavir is being developed as an attachment inhibitor while lenacapavir, VH4004280 and VH4011499 are capsid inhibitors. Others are maturation inhibitors such as GSK-254, GSK3532795, GSK3739937, GSK2838232, and other compounds labelled as miscellaneous (do not belong to the classical groups of anti-HIV drugs or to the newer classes) such as obefazimod and BIT225. There is a considerable progress in the development of new anti-HIV drugs and the effort will continue since HIV infections has no cure or vaccine till now. Efforts are needed to reduce the toxicity of available drugs or discover new drugs with new classes which can delay the development of resistance.

Supporting young women's health through girl-friendly drug vendors in Lake Zone, Tanzania: protocol for the AmbassADDOrs for Health cluster-randomised controlled trial

INTRODUCTION

Adverse sexual and reproductive health (SRH) outcomes, such as unplanned pregnancies and HIV infection, disproportionately affect adolescent girls and young women (AGYW; aged 15-24 years) in east Africa. Increasing uptake of preventive SRH services via innovative, youth-centred interventions is imperative to addressing disparities in SRH outcomes.

METHODS AND ANALYSIS

From 2018 to 2019, we used human-centred design to co-develop a theoretically driven HIV and pregnancy prevention intervention for AGYW at private drug shops called Accredited Drug Dispensing Outlets (ADDOs) in Tanzania. The result, Malkia Klabu (Queen Club), was a customer loyalty programme designed to strengthen ADDOs' role as SRH providers while encouraging uptake of critical SRH prevention products among AGYW. Malkia Klabu members had access to free contraceptives and oral HIV self-test (HIVST) kits and earned punches on a loyalty card for other shop purchases; punches were redeemable for small prizes. Our pilot among 40 shops showed that intervention ADDOs had higher AGYW patronage and distributed more HIVST kits and contraceptives to AGYW relative to business-as-usual (ie, client purchasing) comparison shops. We will conduct a cluster-randomised controlled trial (c-RCT) among 120-140 ADDOs in 40 health catchment areas in Shinyanga and Mwanza Regions (Lake Zone), Tanzania. ADDO shop recruitment includes a 1-month run-in with a tablet-based electronic inventory management system for tracking shop transactions, followed by enrolment, randomisation and a 24-month trial period. Our c-RCT evaluating the human-centred design-derived intervention will assess population impact on the primary outcomes of HIV diagnoses and antenatal care registrations, measured with routine health facility data. We will also assess secondary outcomes focusing on mechanisms of action, evaluate programme exposure and AGYW behaviour change in interviews with AGYW, and assess shop-level implementation strategies and fidelity.

ETHICS AND DISSEMINATION

Ethical approval was granted from both the University of California, San Francisco and the Tanzanian National Institute for Medical Research. Study progress and final outcomes will be posted annually to the National Clinical Trials website; study dissemination will occur at conferences, peer-reviewed manuscripts and local convenings of stakeholders.

TRIAL REGISTRATION NUMBER

NCT05357144.

Preference heterogeneity for HIV pre-exposure prophylaxis care among gay, bisexual, and other men who have sex with men in the United States: a large discrete choice experiment

Background

PrEP uptake among Black and Latino gay, bisexual, and other men who have sex with men (GBM) remains low in the United States. The design and implementation of PrEP delivery programs that incorporate the preferences of Black and Latino GBM may overcome barriers to uptake. We aimed to identify preferences for PrEP care among high-priority GBM in the U.S. with a large discrete choice experiment.

Methods

We conducted two discreet choice experiments (DCE) to elicit care preferences for (1) Starting PrEP and (2) Continuing PrEP care among GBM clinically indicated for PrEP. The DCE web-based survey was nested in a longitudinal cohort study of GBM in the U.S., implemented with video and audio directions among 16-49 year-old participants, not using PrEP, and verified to be HIV-negative. All participants were presented with 16 choice sets, with choices determined by BLGBM and PrEP implementation stakeholders. We calculated overall utility scores and relative importance and used latent class analyses (LCA) to identify classes within the Starting and Continuing PrEP DCE. Multivariable analysis was performed to identify factors associated with class membership.

Findings

Among 1514 participants, mean age was 32 years; 46·5% identified as Latino, 21·4% Black, and 25·2 White; 37·5% had an income less than USD $20,000. Two latent classes were identified for Starting PrEP: Class 1 (n=431 [28·5%]) was driven by preference for more traditional in-person care, and Class 2 (n=1083 [71·5%]) preferred flexible care options and on-demand PrEP. In a multivariable model, having a sexual health doctor (adjusted OR 0·7, CI 0·5, 0·9), having a primary care provider (OR 0·7,CI 0·5, 0·9, p= 0·023), and concerns over PrEP side effects (OR 1·1, CI 1·0,1·2, p= 0·003) were all associated with class membership.

Interpretation

The different preferences identified for PrEP care indicate the need for diverse care and formulation choices to improve PrEP uptake and persistence. Addressing these preferences and understanding the factors that shape them can inform the implementation of programs that increase PrEP uptake.

Acceptability of Event-Driven and Long-Acting HIV Pre-Exposure Prophylaxis Formulations Among Transgender Women Engaged in Street-Based Sex Work in Baltimore, Maryland

We assessed acceptability of nonoral HIV pre-exposure prophylaxis (PrEP) formulations among transgender women (TW) engaged in street-based sex work in Baltimore, Maryland. In a K-means cluster analysis, TW (N=36) were partitioned into groups characterized by high interest in long-acting injectable PrEP only (Injectable Enthusiasts, 36%), high interest in injectables and subdermal implants (Long-Acting Acceptors, 36%), and low interest across PrEP formulations (Non-Acceptors, 28%). TW's interest in novel PrEP agents varied widely across formulations (range: 22-66%) and clustered around numerous relational, occupational, and structural factors, highlighting the importance of availing multiple PrEP formulations for this impacted population.

Intention to Use Different Formulations of Longer Acting HIV Pre-Exposure Prophylaxis Among Transgender and Gender Expansive Individuals: The Roles of Social Vulnerability and Medical Mistrust

In 2012, the Federal Drug Administration approved daily oral pre-exposure prophylaxis (PrEP) for HIV prevention in adults. Longer acting injectable PrEP (LA PrEP) has been approved and other formulations are in development. A successful LA PrEP rollout requires examining potential facilitators and barriers to PrEP uptake. Given that transgender and gender expansive (TGE) individuals experience more social vulnerability and higher levels of medical mistrust compared to other populations, examining the role of these two factors in LA PrEP uptake is important. This study, PrEP for ALL, is a community-based participatory research project in Texas that engaged TGE community members and organizational partners through a community advisory board. In total, 482 TGE individuals were recruited and responded to all relevant questions in an online survey, including their intentions to use three formulations: a monthly oral pill, a bimonthly intramuscular injection, and an annual subdermal implant. Multiple regression analysis was used to examine the influence of social vulnerability and medical mistrust on intention to use each LA PrEP formulation adjusting for other relevant factors. Findings suggest that individuals with higher levels of social vulnerability had greater intentions to use the monthly oral pill (β = 0.12, p = 0.009), the bimonthly intramuscular injection (β = 0.18, p < 0.001), and annual subdermal implant (β = 0.17, p < 0.001), whereas medical mistrust reduced intentions to use the bimonthly intramuscular injection (β = -0.18, p < 0.001) and annual subdermal implant (β = -0.11, p = 0.021). Improvements in gender-affirming clinical care are needed along with LA PrEP formulations that allow for greater autonomy and reduced clinical contact. Clinical Trial Registration number: NCT05044286.

Testing the Effectiveness of a Motivational Interviewing Intervention to Reduce HIV Risk and Drug Use in Young Sexual Minority Men in a Community-Based Organization Setting

Younger sexual minority men (YSMM) remain at high risk for HIV infection and substance use increases this risk. This study evaluated the effectiveness of a (4-session) motivational interviewing (MI) intervention to reduce substance use and sexual risk taking when delivered at two community-based organizations (CBOs) in the New York City metropolitan area. Participants included 86 YSMM aged 15-29 who reported recent sexual HIV transmission risk and substance use. Overall, 86% of the sample identified as a racial or ethnic minority. Within each CBO, participants were randomized to receive either the MI intervention or enhanced treatment as usual (an HIV testing session plus PrEP information and referrals to CBO services). Contrary to hypotheses, results provided no indication that the MI intervention was associated with reductions in substance use (alcohol, cannabis, or other illicit drug use) or sexual risk taking or current PrEP use. Results are discussed in terms of challenges in real world intervention implementation, study enrollment, and the COVID-19 pandemic.

Using audience segmentation to identify implementation strategies to improve PrEP uptake among at-risk cisgender women: a mixed-methods study protocol

BACKGROUND

In the USA, 19% of new HIV infections occur among cisgender women (cis women); however, only 10% of eligible cis women have been prescribed pre-exposure prophylaxis (PrEP) for the prevention of HIV infection (an evidence-based intervention). A fundamental challenge for expanding HIV prevention to cis women is ensuring implementation strategies are tailored to the various healthcare settings in which cis women seek care and the heterogeneous providers nested within these settings. This project's specific aims are to (1) explore clinician-level characteristics and organizational climate factors that are related to variability in adoption of PrEP service delivery as an evidence-based intervention for cis women; (2) identify latent audience segments of women's health providers as the related to PrEP acceptability, adoption, and maintenance and analyze demographic correlates of these segments; and (3) identify audience segment-specific implementation strategies to facilitate the adoption of PrEP as an evidence-based intervention among at-risk cis women.

METHODS

Using the i-PARIHS framework, this mixed-methods study examines three domains for guiding audience segmentation to facilitate PrEP implementation for cis women: innovation (degree of fit with existing practices, usability), recipient beliefs and knowledge and context factors (organizational culture, readiness for change), needs to determine appropriate facilitation methods. To achieve aim 1, qualitative interviews will be conducted with PrEP-eligible cis women, women's health providers, and other key stakeholders. Aim 2 will consist of a quantitative survey among 340 women's health providers. Latent class analysis will be used to facilitate audience segmentation. To achieve aim 3, a panel of 5-8 providers for each audience segment will meet and engage in iterative discussions guided by Fernandez's implementation mapping to identify (1) implementation outcomes and performance objectives, determinants, and change objectives and (2) determine and refine of implementation strategies for each audience segment.

DISCUSSION

This exploratory mixed methods study will provide an empirical foundation to inform the development implementations strategies aimed at increasing PrEP delivery to cis women among heterogenous groups of providers.

Current drugs for HIV-1: from challenges to potential in HIV/AIDS

The human immunodeficiency virus (HIV) persists in latently infected CD4+T cells and integrates with the host genome until cell death. Acquired immunodeficiency syndrome (AIDS) is associated with HIV-1. Possibly, treating HIV/AIDS is an essential but challenging clinical goal. This review provides a detailed account of the types and mechanisms of monotherapy and combination therapy against HIV-1 and describes nanoparticle and hydrogel delivery systems. In particular, the recently developed capsid inhibitor (Lenacapavir) and the Ainuovirine/tenofovir disoproxil fumarate/lamivudine combination (ACC008) are described. It is interestingly to note that the lack of the multipass transmembrane proteins serine incorporator 3 (SERINC3) and the multipass transmembrane proteins serine incorporator 5 (SERINC5) may be one of the reasons for the enhanced infectivity of HIV-1. This discovery of SERINC3 and SERINC5 provides new ideas for HIV-1 medication development. Therefore, we believe that in treating AIDS, antiviral medications should be rationally selected for pre-exposure and post-exposure prophylaxis to avoid the emergence of drug resistance. Attention should be paid to the research and development of new drugs to predict HIV mutations as accurately as possible and to develop immune antibodies to provide multiple guarantees for the cure of AIDS.

Clinical Relevance of Drug Interactions in People Living with Human Immunodeficiency Virus on Antiretroviral Therapy-Update 2022: Systematic Review

BACKGROUND

The clinical outcomes of antiretroviral drugs may be modified through drug interactions; thus, it is important to update the drug interactions in people living with HIV (PLHIV).

AIM

To update clinically relevant drug interactions in PLHIV on antiretroviral therapy with novel drug interactions published from 2017 to 2022.

METHODS

A systematic review in Medline/PubMed database from July 2017 to December 2022 using the Mesh terms antiretroviral agents and drug interactions or herb-drug interactions or food-drug interactions. Publications with drug interactions in humans, in English or Spanish, and with full-text access were retrieved. The clinical relevance of drug interactions was grouped into five levels according to the gravity and probability of occurrence.

RESULTS

A total of 366 articles were identified, with 219 (including 87 citation lists) were included, which allowed for the identification of 471 drug interaction pairs; among them, 291 were systematically reported for the first time. In total 42 (14.4%) and 137 (47.1%) were level one and two, respectively, and 233 (80.1%) pairs were explained with the pharmacokinetic mechanism. Among these 291 pairs, protease inhibitors (PIs) and ritonavir/cobicistat-boosted PIs, as well as integrase strand transfer inhibitors (InSTIs), with 70 (24.1%) and 65 (22.3%) drug interaction pairs of levels one and two, respectively, were more frequent.

CONCLUSIONS

In PLHIV on antiretroviral therapy, we identify 291 drug interaction pairs systematically reported for the first time, with 179 (61.5%) being assessed as clinically relevant (levels one and two). The pharmacokinetic mechanism was the most frequently identified. PIs, ritonavir/cobicistat-boosted PIs, and InSTIs were the antiretroviral groups with the highest number of clinically relevant drug interaction pairs (levels one and two).

Perceptions of Long-Acting Injectable Antiretroviral Therapy Among People Living with HIV Who Use Drugs and Service Providers: a Qualitative Analysis in Rhode Island

Long-acting injectable antiretroviral therapy (LAI-ART) is a novel method to deliver HIV treatment, and the first regimen was approved in the USA in 2021. LAI-ART may mitigate barriers to oral treatment adherence, but little is known about LAI-ART perceptions among people living with HIV (PLWH) who use drugs, despite these populations facing greater barriers to treatment retention and ART adherence. We assessed LAI-ART perceptions and implementation considerations among PLWH who use drugs and health and ancillary service providers in Rhode Island. Data was collected from November 2021 to September 2022, and include in-depth interviews with 15 PLWH who use drugs and two focus groups with HIV clinical providers (n = 8) and ancillary service providers (n = 5) working with PLWH who use drugs. Data were analyzed thematically, with attention paid to how levels of structural vulnerability and social-structural environments shaped participants' LAI-ART perceptions and the HIV care continuum. Willingness to consider LAI-ART was impacted by HIV outcomes (e.g., viral suppression) and previous experiences with oral regimens, with those on stable regimens reluctant to consider alternative therapies. However, LAI-ART was seen as potentially improving HIV outcomes for PLWH who use drugs and enhancing people's quality of life by reducing stress related to daily pill-taking. Recommendations for optimal implementation of LAI-ART varied across participants and included decentralized approaches to delivery. HIV care delivery must consider the needs of PLWH who use drugs. Developing patient-centered and community-based delivery approaches to LAI-ART may address adherence challenges specific to PLWH who use drugs.

Advances in long-acting slow effective release antiretroviral therapies for treatment and prevention of HIV infection

Adherence to daily oral antiretroviral therapy (ART) is a barrier to both treatment and prevention of human immunodeficiency virus (HIV) infection. To overcome limitations of life-long daily regimen adherence, long-acting (LA) injectable antiretroviral (ARV) drugs, nanoformulations, implants, vaginal rings, microarray patches, and ultra-long-acting (ULA) prodrugs are now available or in development. These medicines enable persons who are or at risk for HIV infection to be treated with simplified ART regimens. First-generation LA cabotegravir, rilpivirine, and lenacapavir injectables and a dapivirine vaginal ring are now in use. However, each remains limited by existing dosing intervals, ease of administration, or difficulties in finding drug partners. ULA ART regimens provide an answer, but to date, such next-generation formulations remain in development. Establishing the niche will require affirmation of extended dosing, improved access, reduced injection volumes, improved pharmacokinetic profiles, selections of combination treatments, and synchronization of healthcare support. Based on such needs, this review highlights recent pharmacological advances and a future treatment perspective. While first-generation LA ARTs are available for HIV care, they remain far from ideal in meeting patient needs. ULA medicines, now in advanced preclinical development, may close gaps toward broader usage and treatment options.

Preferences for long-acting pre-exposure prophylaxis among gay, bisexual and other men who have sex with men in Taiwan: findings from the 2021 HEART Survey

INTRODUCTION

While various antiretrovirals have been studied as potential candidates for long-acting pre-exposure prophylaxis (PrEP), the bimonthly injectable cabotegravir-the first long-acting form of PrEP-was approved in 2021. Event-driven (ED) PrEP has been the most prevalent dosing regimen among gay, bisexual and other men who have sex with men (GBMSM) in Taiwan, providing a unique setting to observe the preferences for long-acting PrEP in a community where the daily regimen is not the mainstream method. This study aimed to determine the preferences for the different forms and dosing intervals of long-acting PrEP that are currently in the development pipeline.

METHODS

We conducted a survey in 2021 by convenience sampling the users of social networking applications for GBMSM in Taiwan. Our survey included questions on sexual behaviours, current PrEP regimens and the preferences for potential candidates of long-acting PrEP, such as implants, intramuscular and subcutaneous injections. We compared the Likert-scale preference ratings for potential long-acting options, and conducted logistic regression analysis to examine the factors associated with a preference for bimonthly intramuscular injections (2M IM) over ED and daily PrEP regimens, respectively.

RESULTS

A total of 1728 responses were eligible for analysis. Three percent of respondents (n = 52) were daily PrEP users; 11.5% (n = 198) were ED PrEP users. When not considering cost, current PrEP users-regardless of their original dosing regimen-were most likely to express preferences for monthly oral PrEP, followed by a 6-month subcutaneous injectable (6M SC) and 2M IM. However, among non-current PrEP users, monthly oral PrEP was the most preferred form, followed by ED, daily oral and 6M SC injectable. Multivariable logistic regression revealed that current daily users, those willing to take PrEP in the next 6 months and those with more sex partners in the last 12 months had a significant correlation with preferences for the 2M IM injectable over the ED PrEP.

CONCLUSIONS

The monthly oral form was the most preferable long-acting PrEP among GBMSM in Taiwan. Current daily PrEP users preferred the 2M IM injectable over the ED PrEP, which made the 2M IM injectable a potential alternative. Further studies should focus on how the cost and delivery affect PrEP preferences and their actual uptake.

Pre-exposure prophylaxis service among men who have sex with men in Malaysia: findings from a discrete choice experiment

Men who have sex with men (MSM) in Malaysia are disproportionately affected by HIV. As pre-exposure prophylaxis (PrEP) is being introduced, we assessed population-based PrEP delivery preferences among MSM in Malaysia. We conducted a discrete choice experiment through an online survey among 718 MSM. The survey included 14 choice tasks presenting experimentally varied combinations of five attributes related to PrEP delivery (i.e., cost, dosing strategy, clinician interaction strategy, dispensing venue, and burden of visits to start PrEP). We used latent class analysis and Hierarchical Bayesian modeling to generate the relative importance of each attribute and preference across six possible PrEP delivery programs. PrEP dosing, followed by cost, was the most important attribute. The participants were clustered into five preference groups. Two groups (n = 290) most commonly preferred on-demand, while the other three preferred injectable PrEP. One group (n = 188) almost exclusively considered cost in their decision-making, and the smallest group (n = 86) was substantially less interested in PrEP for reasons unrelated to access. In simulated scenarios, PrEP initiation rates varied by the type of program available to 55·0% of MSM. Successful PrEP uptake among Malaysian MSM requires expanding beyond daily oral PrEP to on-demand and long-acting injectable PrEP, especially at affordable cost.

Structural and Synthetic Aspects of Small Ring Oxa- and Aza-Heterocyclic Ring Systems as Antiviral Activities

Antiviral properties of different oxa- and aza-heterocycles are identified and properly correlated with their structural features and discussed in this review article. The primary objective is to explore the activity of such ring systems as antiviral agents, as well as their synthetic routes and biological significance. Eventually, the structure-activity relationship (SAR) of the heterocyclic compounds, along with their salient characteristics are exhibited to build a suitable platform for medicinal chemists and biotechnologists. The synergistic conclusions are extremely important for the introduction of a newer tool for the future drug discovery program.

Safety and Efficacy of Long-Acting Injectable Agents for HIV-1: Systematic Review and Meta-Analysis

BACKGROUND

HIV-1 infection continues to affect global health. Although antiretrovirals can reduce the viral load or prevent HIV-1 infection, current drugs require daily oral use with a high adherence level. Long-acting antiretrovirals (LA-ARVs) significantly improve medication adherence and are essential for HIV-1 prophylaxis and therapy.

OBJECTIVE

This study aimed to investigate the safety and efficacy of long-acting cabotegravir (CAB-LA) and long-acting rilpivirine (RPV-LA) in the prevention and treatment of HIV-1 infection.

METHODS

PubMed, Embase, and the Cochrane Library were searched for studies from database inception to November 12, 2022. We included studies that reported efficacy and safety data on LA-ARV intervention in people living with HIV and excluded reviews, animal studies, and articles with missing or duplicate data. Virological suppression was defined as plasma viral load <50 copies/mL 6 months after antiviral therapy initiation. We extracted outcomes for analysis and expressed dichotomous data as risk ratios (RRs) and continuous data as mean differences. Depending on the heterogeneity assessment, a fixed- or random-effects model was used for data synthesis. We performed subgroup analyses of the partial safety and efficacy outcomes of CAB-LA+RPV-LA. The protocol was registered with the Open Science Framework.

RESULTS

We included 12 trials comprising 10,957 individuals, of which 7 were prevention trials and 5 were treatment trials. CAB-LA and RPV-LA demonstrated safety profiles comparable with those of the placebo in terms of adverse event-related withdrawal. Moreover, the efficacy data showed that CAB-LA had a better effect on HIV-1 prevention than tenofovir disoproxil fumarate-emtricitabine (17/5161, 0.33% vs 75/5129, 1.46%; RR 0.21, 95% CI 0.07-0.61; I2=70%). Although CAB-LA+RPV-LA had more drug-related adverse events (556/681, 81.6% vs 37/598, 6.2%; RR 12.50, 95% CI 3.98-39.23; I2=85%), a mild or moderate injection site reaction was the most common reaction, and its frequency decreased over time. The efficacy of CAB-LA+RPV-LA was comparable with that of daily oral drugs at 48 and 96 weeks (1302/1424, 91.43% vs 915/993, 92.2%; RR 0.99, 95% CI 0.97-1.02; I2=0%), and a high level of virological suppression of 80.9% (186/230) was maintained even after 5 years of LA-ARV use. Similar efficacy outcomes were observed in both treatment-naive and treatment-experienced patients (849/911, 93.2% vs 615/654, 94%; RR 0.99, 95% CI 0.96-1.02; I2=0%). According to the questionnaires, more than 85% of people living with HIV favored LA-ARVs.

CONCLUSIONS

LA-ARVs showed favorable safety profiles for both the prevention and treatment of HIV-1 infection and were well tolerated. CAB-LA has more satisfactory efficacy than tenofovir disoproxil fumarate-emtricitabine, significantly reducing the rate of HIV-1 infection. CAB-LA+RPV-LA maintains virological suppression for a long time and may be a viable switching strategy with enhanced public health benefits by reducing transmission. However, further trials are required to confirm the efficacy of these drugs.

Long-acting refillable nanofluidic implant confers protection against SHIV infection in nonhuman primates

The impact of pre-exposure prophylaxis (PrEP) on slowing the global HIV epidemic hinges on effective drugs and delivery platforms. Oral drug regimens are the pillar of HIV PrEP, but variable adherence has spurred development of long-acting delivery systems with the aim of increasing PrEP access, uptake, and persistence. We have developed a long-acting subcutaneous nanofluidic implant that can be refilled transcutaneously for sustained release of the HIV drug islatravir, a nucleoside reverse transcriptase translocation inhibitor that is used for HIV PrEP. In rhesus macaques, the islatravir-eluting implants achieved constant concentrations of islatravir in plasma (median 3.14 nM) and islatravir triphosphate in peripheral blood mononuclear cells (median 0.16 picomole per 10⁶ cells) for more than 20 months. These drug concentrations were above the established PrEP protection threshold. In two unblinded, placebo-controlled studies, islatravir-eluting implants conferred 100% protection against infection with SHIV_SF162P3 after repeated low-dose rectal or vaginal challenge in male or female rhesus macaques, respectively, compared to placebo control groups. The islatravir-eluting implants were well tolerated with mild local tissue inflammation and no signs of systemic toxicity over the 20-month study period. This refillable islatravir-eluting implant has potential as a long-acting drug delivery system for HIV PrEP.

Binge Drinking Moderates Unprotected Sex Among HIV Sero-Similar Same Sex Male Couples: An Actor-Partner Interdependence Model

Most new HIV diagnoses in the US occur among sexual minority men (SMM). The majority (69%) of new HIV diagnoses among US SMM are due to transmission from main sex partners. We identified multilevel correlates of unprotected anal intercourse (UAI; condomless anal intercourse while not using a biomedical strategy) among SMM couples using the Actor Partner Interdependence Model (APIM). Participants were US SMM over 18 years, with a primary male partner > 6 months. Couples were recruited online from April 2016 until June 2017 and interviewed using self-administered computer-assisted surveys. We used a series of APIM regressions to assess multilevel associations with UAI. We also tested the moderating role of an individual's binge drinking on the relationship between HIV status similarity and UAI. Among 798 participants (n = 411 couples), 61% reported UAI in the past 6 months. Binge drinking (52%) and physical intimate partner violence (IPV; 34%) were considerably high within our sample. Actor's binge drinking, reporting experiencing and/or perpetrating physical IPV, and partner's trust were positively associated with UAI. Actor having other sexual partner(s), using illegal drugs (not marijuana), and length of relationship were negatively associated with UAI. Binge drinking positively moderated UAI among HIV serostatus similar partners. HIV prevention programming should integrate components on IPV and binge drinking reduction- especially among HIV serostatus similar couples.

Changes in Cost and Insurance Challenges to Cover PrEP Between 2019 and 2021

INTRODUCTION

Pre-Exposure Prophylaxis (PrEP) use continues lag estimated need among gay and bisexual men in the United States. Studies report that challenges paying for PrEP may undermine continued use. Our study aimed to measure these challenges over time.

METHODS

Data were taken from a US national cohort study of cisgender gay and bisexual men and transgender individuals aged 16-49 years. We analyzed data from PrEP-using participants between 2019 and 2021 and observed cost-related and insurance-related challenges participants experienced while on PrEP across time points. We report McNemar and Cochrane Q test statistics to compare differences between groups by year(s).

RESULTS

In 2019, 16.5% (n = 828/5013) of participants were on PrEP; by 2020, 21% (n = 995/4727) were on PrEP, and by 2021, 24.5% (n = 1133/4617) were on PrEP. The proportion of those experiencing challenges paying for PrEP care decreased significantly across time points for clinical appointments, laboratory work, and prescriptions. Those experiencing insurance and copay approval issues did not change significantly. Although not statistically significant, the only proportion that increased over time was those reporting PrEP-related insurance approval issues. In a post hoc analysis, we found that those reporting PrEP use in the past year who were not currently on PrEP were significantly more likely to report experiencing most PrEP challenges, when compared with current PrEP users.

DISCUSSION

We found significant reductions in insurance and cost-related challenges between 2019 and 2021. However, those who discontinued PrEP within the past year reported greater challenges paying for PrEP, suggesting that cost and insurance issues may undermine PrEP persistence.

Dynamics of Pre-Exposure (PrEP) Eligibility Because of Waxing and Waning of HIV Risk in Rakai, Uganda

BACKGROUND

We conducted a retrospective population-based study to describe longitudinal patterns of prevalence, incidence, discontinuation, resumption, and durability of substantial HIV risk behaviors (SHR) for pre-exposure prophylaxis (PrEP) eligibility.

METHODS

The study was conducted among HIV-negative study participants aged 15-49 years who participated in survey rounds of the Rakai Community Cohort Study between August 2011 and June 2018. Substantial HIV risk was defined based on the Uganda national PrEP eligibility as reporting sexual intercourse with >1 partner of unknown HIV status, nonmarital sex without a condom, having genital ulcers, or having transactional sex. Resumption of SHR meant resuming of SHR after stopping SHR, whereas persistence of SHR meant SHR on >1 consecutive visit. We used generalized estimation equations with log-binomial regression models and robust variance to estimate survey-specific prevalence ratios; Generalized estimation equations with modified Poisson regression models and robust variance to estimate incidence ratios for incidence, discontinuation, and resumption of PrEP eligibility.

FINDINGS

Incidence of PrEP eligibility increased from 11.4/100 person-years (pys) in the first intersurvey period to 13.9/100 pys (adjusted incidence rate ratios = 1.28; 95%CI = 1.10-1.30) and declined to 12.6/100 pys (adjusted incidence rate ratios = 1.06; 95%CI = 0.98-1.15) in the second and third intersurvey periods, respectively. Discontinuation rates of SHR for PrEP eligibility were stable (ranging 34.9/100 pys-37.3/100 pys; P = 0.207), whereas resumption reduced from 25.0/100 pys to 14.5/100 pys ( P < 0.001). PrEP eligibility episodes lasted a median time of 20 months (IQR = 10-51).

INTERPRETATION

Pre-exposure prophylaxis use should be tailored to the dynamic nature of PrEP eligibility. Preventive-effective adherence should be adopted for assessment of attrition in PrEP programs.

Integrating Gender-Based Violence Screening and Support into the Research Clinic Setting: Experiences from an HIV Prevention Open-Label Extension Trial in Sub-Saharan Africa

HIV and gender-based violence (GBV) are syndemic in sub-Saharan Africa and provision of support for participants who disclose GBV constitutes part of comprehensive care. Consequently, a process was undertaken to develop, implement, and evaluate standard operating procedures (SOPs) in MTN-025/HOPE, a study of the dapivirine vaginal ring for HIV prevention. The SOP was developed using needs assessment surveys in addition to World Health Organization (WHO) guidelines and other literature. Sites tailored and implemented the SOP through HOPE implementation. At study end, staff reported increased training 32/35 (91.43%); improved confidence (18/26; 69.23%); and improved vicarious trauma prevention onsite (17/28; 60.71%). Leadership reported increased staff competence in GBV response. Obstacles included limited referral organizations and time for follow-up, continued training needs, and cultural norms. Development and implementation of an SOP is a feasible strategy to build a GBV response to improve health systems and support sustained effective use of HIV prevention products.

Cabotegravir: The First Long-Acting Injectable for HIV Preexposure Prophylaxis

OBJECTIVE

Review the pharmacology, pharmacokinetics, efficacy, safety, and role of long-acting injectable cabotegravir (CAB-LA) in HIV preexposure prophylaxis (PrEP).

DATA SOURCES

A literature search was performed using PubMed and Google Scholar (2012 to April 2022) with the search terms cabotegravir, preexposure prophylaxis, and PrEP. Other resources included abstracts presented at recent conferences, the manufacturer's Web site, prescribing information, and review articles.

STUDY SELECTION AND DATA EXTRACTION

All English-language articles of studies assessing the efficacy and safety of CAB-LA for PrEP were included.

DATA SYNTHESIS

CAB-LA is the first long-acting injectable therapy approved for HIV-1 PrEP in both men and women. It is a suspension given intramuscularly every other month. CAB-LA has been shown to be more effective than daily oral tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) in preventing HIV-1 infection among high-risk individuals. Two phase 3 trials were stopped early on the basis of superior efficacy of CAB-LA. The most common adverse effects were injection site reactions (ISRs), although they tended to decrease over time, and few participants in clinical trials discontinued use due to ISRs.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

CAB-LA may be particularly useful for individuals with known adherence problems to oral therapy, those with renal impairment, and those with decreased bone mineral density. However, CAB-LA is more expensive than generic TDF/FTC and may be associated with weight gain.

CONCLUSIONS

CAB-LA is the first long-acting injectable agent for HIV PrEP. It is more effective than oral TDF/FTC, is well-tolerated aside from ISRs, and has few clinically significant drug-drug interactions.

Approved Nanomedicine against Diseases

Nanomedicine is a branch of medicine using nanotechnology to prevent and treat diseases. Nanotechnology represents one of the most effective approaches in elevating a drug‘s treatment efficacy and reducing toxicity by improving drug solubility, altering biodistribution, and controlling the release. The development of nanotechnology and materials has brought a profound revolution to medicine, significantly affecting the treatment of various major diseases such as cancer, injection, and cardiovascular diseases. Nanomedicine has experienced explosive growth in the past few years. Although the clinical transition of nanomedicine is not very satisfactory, traditional drugs still occupy a dominant position in formulation development, but increasingly active drugs have adopted nanoscale forms to limit side effects and improve efficacy. The review summarized the approved nanomedicine, its indications, and the properties of commonly used nanocarriers and nanotechnology.

Preferences for PrEP modalities among gay, bisexual, and other men who have sex with men from Brazil, Mexico, and Peru: a cross-sectional study

Background

Pre-exposure prophylaxis (PrEP) scale-up is urgent to reduce new HIV cases among gay, bisexual, and other men who have sex with men (MSM) in Latin America. Different PrEP modalities may increase PrEP uptake and adherence, especially among young MSM.

Objectives

To assess preferences for PrEP modalities among MSM from Brazil, Mexico, and Peru.

Design

Cross-sectional web-based study (March-May 2018) targeting MSM through advertisements on Grindr, Hornet, and Facebook. We included MSM aged ⩾ 18 years and who reported HIV-negative status.

Methods

We assessed preferences for PrEP modalities with the following question: 'Considering that all following PrEP modalities were available, which one would you prefer considering a scale from 1 to 3 (1 = most preferred): daily oral PrEP, event-driven PrEP (ED-PrEP), and long-acting injectable PrEP'. We assessed factors associated with each most preferred PrEP modality per country using multivariable logistic regression models.

Results

A total of 19,457 MSM completed the questionnaire (Brazil: 58%; Mexico: 31%; Peru: 11%); median age was 28 years [interquartile range (IQR): 24-34]. Overall, injectable PrEP was the most preferred modality [42%; 95% confidence interval (CI): 41-43], followed by daily PrEP (35%; 95% CI: 34-35), and ED-PrEP (23%; 95% CI: 23-24). In multivariable models, preferring injectable PrEP was associated with PrEP awareness in all three countries, while PrEP eligibility only in Brazil. Preferring daily PrEP was associated with younger age and lower income in Brazil and Mexico, and lower education only in Brazil. The odds of preferring ED-PrEP were lower among MSM aware and eligible for PrEP in Brazil and Mexico.

Conclusions

Long-acting injectable PrEP was the preferred PrEP modality among MSM in Brazil, Mexico, and Peru, especially those aware and eligible for PrEP. Public health interventions to increase PrEP modalities literacy and availability in Latin America are urgent especially among MSM of young age, lower income, and lower education.

Primary resistance to integrase inhibitors in Shenzhen

OBJECTIVES

In recent years, integrase strand transfer inhibitor (INSTI)-containing regimens have been increasingly adopted in treatment for HIV/AIDS and promoted as non-occupational post-exposure prophylaxis in China. This study aims to describe the prevalence of resistance to integrase and drug resistance mutations (DRMs) among ART-naive patients in Shenzhen, China.

METHODS

Serum samples and demographic information were collected from newly reported ART-naive patients in Shenzhen in 2020. The study sequenced the coding sequence of the HIV-1 integrase gene and determined the DRMs.​.

RESULTS

In this study, 1682 newly reported cases were included and 1071 of them were successfully sequenced finally. The prevalence of primary drug resistance was 1.77%, with 19 samples showing varying degrees of resistance to INSTIs. The study detected six major DRMs in 16 individuals and eight accessory DRMs in 24 individuals. The prevalence of transmitted drug resistance (TDR) mutations was 1.21%, with five transmitted mutations detected in 13 individuals. The prevalence of drug resistance to raltegravir and elvitegravir was statistically higher than to bictegravir, cabotegravir and dolutegravir.

CONCLUSIONS

The prevalence of INSTI resistance in Shenzhen in 2020 was relatively high. ​Continued surveillance for resistance to INSTIs is recommended and treatment regimens should be adopted based on the pattern of resistance to INSTIs. ​Dolutegravir or bictegravir is first recommended when considering INSTIs as treatment regimens.

Estimating benefits of using on-demand oral prep by MSM: A comparative modeling study of the US and Thailand

BACKGROUND

Daily and on-demand pre-exposure prophylaxis (PrEP) are effective at preventing HIV acquisition among men who have sex with men (MSM), but only daily PrEP is approved in the US. On-demand PrEP may improve uptake and adherence. We identify sub-groups of MSM who would benefit from on-demand PrEP and determine effectiveness achieved if individuals used their optimal regimens.

METHODS

Using data from the HPTN 067 study (study period 2012-2014), we created an individual-based stochastic model of HIV risk in two synthetic MSM populations with parameters separately estimated using data from Harlem, US, and Bangkok, Thailand. Agents were assigned daily and on-demand PrEP for six months each. Two personalized PrEP assignments: optimal, based on improved predicted effectiveness and reduced pill burden, and adherence-based, using daily PrEP adherence, were simulated for another six months.

FINDINGS

Simulated on-demand PrEP was optimal for approximately one-third of MSM. It was assigned mainly to those with low daily PrEP adherence (88% (Harlem), 95% (Bangkok) of MSM with daily PrEP adherence <40%). Mean effectiveness was slightly higher in the full synthetic population with optimal PrEP assignment compared to universal daily PrEP. Among MSM for whom on-demand PrEP was optimal, mean effectiveness improved by 18 (Harlem) and 7 percentage points (Bangkok). Comparable predicted effectiveness was achieved if on-demand PrEP was assigned to the population with daily PrEP adherence <50%. There was no advantage in assigning on-demand PrEP by sex act frequency.

INTERPRETATION

On-demand PrEP could benefit many MSM by increasing effectiveness or decreasing pill burden with similar effectiveness. On-demand PrEP may be an effective alternative to daily PrEP for individuals with difficulty taking daily PrEP consistently. Results were similar for Harlem and Bangkok, indicating that these conclusions were robust in populations with different overall adherence levels and may inform future public-health policies.

FUNDING

US NIH grant UM1 AI068617.

The role of machine learning in HIV risk prediction

Despite advances in reducing HIV-related mortality, persistently high HIV incidence rates are undermining global efforts to end the epidemic by 2030. The UNAIDS Fast-track targets as well as other preventative strategies, such as pre-exposure prophylaxis, have been identified as priority areas to reduce the ongoing transmission threatening to undermine recent progress. Accurate and granular risk prediction is critical for these campaigns but is often lacking in regions where the burden is highest. Owing to their ability to capture complex interactions between data, machine learning and artificial intelligence algorithms have proven effective at predicting the risk of HIV infection in both high resource and low resource settings. However, interpretability of these algorithms presents a challenge to the understanding and adoption of these algorithms. In this perspectives article, we provide an introduction to machine learning and discuss some of the important considerations when choosing the variables used in model development and when evaluating the performance of different machine learning algorithms, as well as the role emerging tools such as Shapely Additive Explanations may play in helping understand and decompose these models in the context of HIV. Finally, we discuss some of the potential public health and clinical use cases for such decomposed risk assessment models in directing testing and preventative interventions including pre-exposure prophylaxis, as well as highlight the potential integration synergies with algorithms that predict the risk of sexually transmitted infections and tuberculosis.

PrEP service delivery preferences of black Cis-gender women living in the Southern United States

To assess PrEP service delivery preferences among Black cis-gender women living in urban and rural settings in Alabama, we conducted a cross-sectional discrete choice experiment survey. Discrete choice experiments included five attributes. Hierarchical Bayes (HB) modeling and latent class analyses (LCA) were used to evaluate attribute preferences. Among 795 Black cis-gender HIV-negative women, almost two-thirds lived in urban settings and reported having at least some college; about a third reported a household income less than $25,000 annually; and reported willingness to use PrEP. Respondents placed the greatest importance on PrEP medication formulation and healthcare facility. LCA showed the group with the highest rural proportion preferred for on-line visits. Black women in the Deep South had distinct preferences regarding PrEP service delivery. These findings can inform tailored interventions to improve PrEP uptake among Black cis-gender women across diverse settings in the South.

Long-Acting Injectable Cabotegravir for HIV Prevention: What Do We Know and Need to Know about the Risks and Consequences of Cabotegravir Resistance?

PURPOSE OF REVIEW

Cabotegravir is a potent integrase strand transfer inhibitor (INSTI) recently approved as a long-acting injectable formulation for HIV prevention (CAB-LA). We summarize what is known about cabotegravir pharmacokinetics, activity, and emergence of resistance from in vitro, macaque and clinical studies, and we evaluate the risk of resistance from CAB-LA with on-time injections and after CAB-LA discontinuation.

RECENT FINDINGS

The accumulation of multiple INSTI mutations is required for high-level cabotegravir resistance, and the same mutation combinations may cause cross-resistance to dolutegravir, which is widely used for first-line antiretroviral therapy in low- and middle-income countries. Though CAB-LA was highly effective in preventing HIV, breakthrough infections did occur in trials of CAB-LA despite on-time injections, resulting in selection of single and combinations of INSTI resistance mutations. As CAB-LA is scaled-up, prompt HIV diagnosis to prevent resistance, and resistance monitoring could help preserve the effectiveness of INSTIs for both HIV treatment and prevention.

Modeling the potential impact of pre-exposure prophylaxis for HIV among men who have sex with men in Cameroon

Background

Men who have sex with men (MSM) are consistently burdened by HIV at higher levels than other adults. While HIV prevention programs for MSM are growing in coverage and quality, HIV incidence remains high. In response, pre-exposure prophylaxis (PrEP) was introduced in 2019 to support HIV risk reduction among MSM in Cameroon. Understanding how PrEP initiation programs will change the HIV prevalence among MSM in Cameroon is important to developing effective programs.

Methods

This study uses a mathematical model to simulate population-level HIV transmission among MSM in the cities of Yaoundé and Douala, Cameroon. PrEP is incorporated into the model at rates that equal 25%, 50%, or 75% coverage after twenty years to assess the potential effects on HIV prevalence among MSM, requiring annual initiation rates of 2.5%, 6.8%, and 17.2% for Yaoundé and 2.2%, 5.6%, and 13.4% for Douala, respectively. The data utilized for this model are from a cross sectional study which recruited MSM through respondent-driven sampling of MSM in two major cities in Cameroon: Yaoundé and Douala.

Results

The model estimated an HIV prevalence of 43.2% among MSM, annual HIV diagnoses of 300 per 10,000 MSM and antiretroviral therapy (ART) coverage of 53.9% in Yaoundé. In Douala, estimated prevalence is 26.5% among MSM, 167 per 10,000 MSM annual diagnoses and ART coverage of 72.0%. Standalone PrEP interventions aimed at 50% coverage at the end of a 20-year program would reduce the prevalence from 43.2% to 35.4% in Yaoundé and from 26.5 to 20.1% in Douala. Combining PrEP with a 10% increase in HIV testing would decrease the number of MSM living with HIV and unaware of their status from 9.8 to 6.0% in Yaoundé and from 8.7 to 4.6% in Douala.

Conclusions

PrEP would be beneficial in reducing prevalence even at varying initiation and coverage levels. Combination of PrEP and increased HIV testing further decreased the number of undiagnosed MSM. This study supports the utility of implementing PrEP as part of comprehensive HIV prevention programming among MSM in Cameroon.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07738-z.

Bictegravir nanomicelles and anionic pullulan loaded vaginal film: Dual mechanistic pre-exposure prophylaxis (PrEP) for HIV

Locally delivered pre-exposure prophylaxis (PrEP) has proven to be a promising strategy to combat Human immunodeficiency virus (HIV) transmission but several findings encountered toxicities or proved to be marginally effective in clinical settings. Therefore, innovative, multifunctional, and safer alternatives are being progressively investigated. Herein, we explored negatively charged carbohydrate, anionic pullulan (AP) as a rapidly soluble film-former and novel anti-HIV agent. Additionally, Bictegravir (BCT), an HIV integrase inhibitor was co-delivered in the form of nanomicelles for sustained antiviral activity. BCT-loaded PLGA-PEG polymeric nanomicelles (BN) were incorporated into PVA/pullulan-based film matrix comprising of 2 % w/v AP (BN-AP film). In cell-based assays, biocompatibility and TEER values for BN-AP films were similar to control while the commercial vaginal contraceptive film (VCF®) showed severe cytotoxicity and drastically reduced the tight junction integrity. Rapid disintegration of BN-AP film with >85 % drug release was observed in simulated vaginal and seminal fluid. Most importantly, AP and BN-AP film significantly inhibited HIV-1 replication with IC₅₀ at as low as 91 μg/mL and 0.708 nM, respectively. Therefore, this study entails successful development of BN-AP film that functioned as an effective, biocompatible dual-acting PrEP formulation.

How could HIV-1 drug resistance impact preexposure prophylaxis for HIV prevention?

PURPOSE OF REVIEW

To review current laboratory and clinical data on the frequency and relative risk of drug resistance and range of mutations selected from approved and investigational antiretroviral agents used for preexposure prophylaxis (PrEP) of HIV-1 infection, including tenofovir disproxil fumarate (TDF)-based oral PrEP, dapivirine ring, injectable cabotegravir (CAB), islatravir, lenacapavir and broadly neutralizing antibodies (bNAbs).

RECENT FINDINGS

The greatest risk of HIV-1 resistance from PrEP with oral TDF/emtricitabine (FTC) or injectable CAB is from starting or continuing PrEP after undiagnosed acute HIV infection. By contrast, the dapivirine intravaginal ring does not appear to select nonnucleoside reverse transcriptase inhibitor resistance in clinical trial settings. Investigational inhibitors including islatravir, lenacapavir, and bNAbs are promising for use as PrEP due to their potential for sustained delivery and low risk of cross-resistance to currently used antiretrovirals, but surveillance for emergence of resistance mutations in more HIV-1 gene regions (gag, env) will be important as the same drugs are being developed for HIV therapy.

SUMMARY

PrEP is highly effective in preventing HIV infection. Although HIV drug resistance from PrEP use could impact future options in individuals who seroconvert on PrEP, the current risk is low and continued monitoring for the emergence of resistance and cross-resistance during product development, clinical studies, and product roll-out is advised to preserve antiretroviral efficacy for both treatment and prevention.

High Rates of Pre-exposure Prophylaxis Eligibility and Associated HIV Incidence in a Population With a Generalized HIV Epidemic in Rakai, Uganda

BACKGROUND

The utility of using pre-exposure prophylaxis (PrEP) eligibility assessments to identify eligibility in general populations has not been well studied in sub-Saharan Africa. We used the Rakai Community Cohort Study to conduct a cross-sectional analysis to estimate PrEP eligibility and a cohort analysis to estimate HIV incidence associated with PrEP eligibility.

METHODS

Based on Uganda's national PrEP eligibility tool, we defined eligibility as reporting at least one of the following HIV risks in the past 12 months: sexual intercourse with more than one partner of unknown HIV status; nonmarital sex act without a condom; sex engagement in exchange for money, goods, or services; or experiencing genital ulcers. We used log-binomial and modified Poisson models to estimate prevalence ratios for PrEP eligibility and HIV incidence, respectively.

FINDINGS

We identified 12,764 participants among whom to estimate PrEP eligibility prevalence and 11,363 participants with 17,381 follow-up visits and 30,721 person-years (pys) of observation to estimate HIV incidence. Overall, 29% met at least one of the eligibility criteria. HIV incidence was significantly higher in PrEP-eligible versus non-PrEP-eligible participants (0.91/100 pys versus 0.41/100 pys; P < 0.001) and independently higher in PrEP-eligible versus non-PrEP-eligible female participants (1.18/100 pys versus 0.50/100 pys; P < 0.001). Among uncircumcised male participants, HIV incidence was significantly higher in PrEP-eligible versus non-PrEP-eligible participants (1.07/100 pys versus 0.27/100 pys; P = 0.001), but there was no significant difference for circumcised male participants.

INTERPRETATION

Implementing PrEP as a standard HIV prevention tool in generalized HIV epidemics beyond currently recognized high-risk key populations could further reduce HIV acquisition and aid epidemic control efforts.

Promises and challenges: cabotegravir for preexposure prophylaxis

PURPOSE OF REVIEW

Tenofovir-based oral PrEP has been effective in reducing population-level HIV incidence in multiple settings, although disparities remain. Injectable cabotegravir-based PrEP is an alternative that may be attractive to individuals with adherence challenges or who do not desire to take a daily medication. We review promises and challenges of cabotegravir-based PrEP.

RECENT FINDINGS

Cabotegravir has demonstrated higher effectiveness than oral PrEP in two randomized trials, with a hazard ratio of 0.31 for HIV incidence among MSM and transgender women across multiple settings [95% confidence interval (CI) 0.18-0.62] and 0.11 for cisgender women in sub-Saharan Africa (95% CI 0.040.32). Cabotegravir was also highly effective among populations with disproportionate HIV incidence. Although cabotegravir breakthrough was rare, diagnosis was delayed with use of antigen/antibody-based HIV tests, and resistance occurred with breakthrough infections. Implementation will need to overcome several challenges, including HIV RNA laboratory monitoring not being widely available, requirement for additional staff time and clinic space, and need to provide oral medication during interruptions in dosing.

SUMMARY

Cabotegravir-based PrEP is a highly effective additional PrEP option that will expand HIV prevention options. For successful roll-out, strategies for streamlined and accessible delivery of cabotegravir in real-world settings will need to be developed.

Transformation of dolutegravir into an ultra-long-acting parenteral prodrug formulation

Ultra-long-acting integrase strand transfer inhibitors were created by screening a library of monomeric and dimeric dolutegravir (DTG) prodrug nanoformulations. This led to an 18-carbon chain modified ester prodrug nanocrystal (coined NM2DTG) with the potential to sustain yearly dosing. Here, we show that the physiochemical and pharmacokinetic (PK) formulation properties facilitate slow drug release from tissue macrophage depot stores at the muscle injection site and adjacent lymphoid tissues following single parenteral injection. Significant plasma drug levels are recorded up to a year following injection. Tissue sites for prodrug hydrolysis are dependent on nanocrystal dissolution and prodrug release, drug-depot volume, perfusion, and cell-tissue pH. Each affect an extended NM2DTG apparent half-life recorded by PK parameters. The NM2DTG product can impact therapeutic adherence, tolerability, and access of a widely used integrase inhibitor in both resource limited and rich settings to reduce HIV-1 transmission and achieve optimal treatment outcomes.

Long-acting preexposure prophylaxis in low- and middle-income countries: key considerations for implementation

PURPOSE OF REVIEW

HIV preexposure prophylaxis (PrEP) is a key tool in ending the HIV epidemic. Long-acting cabotegravir (LA- CAB) phase II/III studies revealed promising efficacy in preventing HIV acquisition. Here, we discuss key considerations for implementing LA-CAB in low- and middle-income countries (LMIC).

RECENT FINDINGS

PrEP roll out in LMIC is still far from ideal, and contextual factors within LMIC vary widely. Implementation science studies are urgently needed to optimize the implementation of LA-CAB in different settings, consider effective service delivery models, and ensure program sustainability. Preferences and concerns regarding LA-CAB among potential users are unknown but likely specific to local context. Demedicalized and simplified PrEP service delivery increases uptake, and ways to safely and effectively do the same for LA- CAB need to be explored. Although ideally LA-CAB should be an additional choice of HIV prevention method, its cost will be the major determinant in deciding its position as a first line choice or restricted second-line option.

SUMMARY

LA-CAB has the potential to enhance PrEP uptake. However, several implementation challenges need to be explored and addressed to ensure it can be accessed and utilized in different settings by those who need it the most.

Long-Acting Injectable ART and PrEP Among Women in Six Cities Across the United States: A Qualitative Analysis of Who Would Benefit the Most

Long-acting injectable (LAI) modalities have been developed for ART and PrEP. Women face unique barriers to LAI use yet little research has examined women's perceptions of potential LAI HIV therapy candidates. We conducted 89 in-depth interviews at six Women's Interagency HIV Study (WIHS) sites with women living with HIV (n = 59) and HIV-negative women (n = 30) from 2017 to 2018. Interviews were recorded, transcribed, and analyzed using thematic content analysis. Participants identified specific sub-populations who could most benefit from LAI over daily pills: (1) young people; (2) women with childcare responsibilities; (3) people with adherence-related psychological distress; (4) individuals with multiple sex partners; and (5) people facing structural insecurities such as homelessness. Women are underserved by current HIV care options and their perspectives are imperative to ensure a successful scale-up of LAI PrEP and LAI ART that prioritizes equitable access and benefit for all individuals.

PrEP distribution in pharmacies: a systematic review

INTRODUCTION

Novel mechanisms of service delivery are needed to expand access to pre-exposure prophylaxis (PrEP) for HIV prevention. Providing PrEP directly through pharmacies could offer an additional option for reaching potential users.

METHODS

We conducted a systematic review of studies examining effectiveness, values and preferences of end users and health workers, and cost of PrEP initiation and continuation through pharmacies (pharmacy access). We searched PubMed, CINAHL, LILACS and EMBASE through 2 December 2020. We also searched clinical trial registries and recent HIV conference abstracts. Standardised methods were used to search, screen and extract data from included studies.

RESULTS

No studies met the inclusion criteria for the effectiveness review, for either PrEP initiation or continuation. However, six 'case studies' presenting non-comparative data from PrEP pharmacy programmes demonstrated feasibility of this model in the USA. Eleven studies reported values and preferences of end users and health workers. In the USA, Kenya and South Africa, potential PrEP clients generally supported pharmacy access, although some preferred clinics. One study of PrEP pharmacy clients found all would 'definitely recommend' the programme. Six studies found pharmacists were generally supportive of offering PrEP; one study including doctors found more limited favour, while one study of diverse Kenyan stakeholders found broad support. Three studies reported cost data indicating client willingness to pay in the USA and Kenya and initial sustainability of a clinic financial model in the USA.

CONCLUSION

Provision of PrEP through pharmacies has been demonstrated to be feasible in the USA and acceptable to potential end users and stakeholders in multiple settings. Limited evidence on effectiveness and requirements for laboratory testing and assurance of high-quality services may limit enthusiasm for this approach. Further research is needed to determine if pharmacy access is a safe and effective way to help achieve global HIV prevention goals.

PROSPERO REGISTRATION NUMBER

CRD42021231650.

OUP accepted manuscript

Background

Effective, long-acting prevention approaches are needed to reduce human immunodeficiency virus (HIV) incidence. We evaluated the safety and pharmacokinetics of VRC07-523LS and PGT121 administered subcutaneously alone and in combination as passive immunization for young women in South Africa.

Methods

CAPRISA 012A was a randomized, double-blinded, placebo-controlled, dose-escalation phase 1 trial. We enrolled 45 HIV-negative women into 9 groups and assessed safety, tolerability, pharmacokinetics, neutralization activity, and antidrug antibody levels. Pharmacokinetic modeling was conducted to predict steady-state concentrations for 12- and 24-weekly dosing intervals.

Results

VRC07-523LS and PGT121, administered subcutaneously, were safe and well tolerated. Most common reactogenicity events were injection site tenderness and headaches. Nine product-related adverse events were mild and transient. Median VRC07-523LS concentrations after 20 mg/kg doses were 9.65 μg/mL and 3.86 μg/mL at 16 and 24 weeks. The median week 8 concentration after the 10 mg/kg PGT121 dose was 8.26 μg/mL. Modeling of PGT121 at 20 mg/kg showed median concentrations of 1.37 μg/mL and 0.22 μg/mL at 16 and 24 weeks. Half-lives of VRC07-523LS and PGT121 were 29 and 20 days. Both antibodies retained neutralizing activity postadministration and no antidrug antibodies were detected.

Conclusions

Subcutaneous administration of VRC07-523LS in combination with optimized versions of PGT121 or other antibodies should be further assessed for HIV prevention.

Suboptimal uptake, retention, and adherence of daily oral PrEP among people with OUD receiving HCV treatment

Background

Daily oral preexposure prophylaxis (PrEP) with tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC) prevents human immunodeficiency (HIV) among people who inject drugs (PWID). Despite rising HIV incidence and injection drug use (IDU), PrEP use remains low and there is limited research about uptake, adherence, and retention among PWID.

Methods

The ANCHOR investigation evaluated a community-based care model collocating hepatitis C virus (HCV) treatment, medication for opioid use disorder (OUD), and PrEP in individuals in Washington, DC, and Baltimore, Maryland. PrEP counseling was conducted from HCV treatment day 0 until week 24. Subjects could start any time during this window, were followed for 48 weeks, and were assessed for adherence by self-report and dried blood spot TDF analysis.

Results

One hundred ninety-eight participants were enrolled, of whom 185 (93%) were HIV negative. Twenty-nine individuals (15.7% of HIV-negative cohort) initiated PrEP. One hundred sixteen participants (62.7%) met 2014 Centers for Disease Control and Prevention (CDC) PrEP criteria due to IDU (82 [44.3%]), sex (9 [4.9%]), or both practices (25 [13.5%]). Providers recommended PrEP to 94 individuals (50.8%), and recommendation was associated with PrEP uptake. Median treatment duration was 104 days (interquartile range, 28–276 days), with 8 participants retained through week 48. Adherence was variable over time by self-report and declined by TDF analysis. No HIV seroconversions occurred.

Conclusions

This cohort of people with HCV and OUD experienced low uptake of PrEP despite the majority meeting CDC criteria. High rates of disruption and discontinuation, compounded by variable adherence, made TDF/FTC a suboptimal prevention strategy. Emerging modalities like long-acting formulations may address these barriers, but PWID have been excluded from their development to date.

Pharmacokinetic interactions of modern antiretroviral therapy

Drug--drug interactions (DDIs) have been a clinical challenge in HIV medicine for over two decades. The newer antiretroviral drugs (ARTs) have significantly fewer DDIs than protease inhibitors and boosted integrase inhibitors (INSTIs). The lower propensity of such newer antiretrovirals (e.g. unboosted integrase inhibitors; doravirine) to cause DDIs, has been largely offset by the ageing cohort of patients with multiple comorbidities, who are taking multiple chronic medicines. Furthermore, the introduction of newly marketed drugs into clinical practice needs to be closely monitored, as the new drugs may be perpetrators of DDIs, leading to a potential change in the efficacy or toxicity of the coadministered antiretrovirals.

Knowledge of HIV and HIV pre-exposure prophylaxis among medical and pharmacy students: A national, multi-site, cross-sectional study

Pre-exposure prophylaxis (PrEP) is a highly effective strategy for preventing HIV. However, prescription of PrEP has not reached the scale that is necessary to meet the public health need of reducing HIV incidence. A factor contributing to this slow scale-up is limited healthcare practitioners' knowledge of PrEP, making PrEP education a priority. We conducted a national, cross-sectional study of medical (allopathic and osteopathic) and pharmacy students regarding knowledge of PrEP and HIV between October 2020 and February 2021. We included 28 items in our knowledge assessment. Analysis sought to identify gaps in knowledge as well as academic and demographic correlates of knowledge. A total of 2,353 students participated in the study (response rate = 17.0%). The overall mean HIV knowledge score was 79.6% correct. Regarding specific items, 68.7% of participants believed HIV treatment was difficult because it required many pills, and 61.1% incorrectly indicated a person with an undetectable HIV viral load could transmit the virus to their sexual partners. Overall mean PrEP knowledge was 84.1%. Approximately one-third of participants did not identify HIV-negative status as a requirement to be a PrEP candidate. Gay/lesbian participants and those who were in the late-phase of training reported higher knowledge of both HIV and PrEP than did heterosexual participants and those in the early-phase of training. This study identifies specific gaps in training on HIV prevention with PrEP that must be improved in health professions education to ensure PrEP reaches its full potential in ending the HIV epidemic.

A new engineering process of biodegradable polymeric solid implants for ultra-long-acting drug delivery

We present a long-acting (LA) biodegradable polymeric solid implant (PSI) fabricated using a new process combining in-situ phase inversion and compression. This robust process allows fabrication of solid implants that can have different shapes and sizes, accommodate high drug payloads, and provide sustained drug release over several months. Herein the integrase inhibitor dolutegravir (DTG) was used to develop PSIs for HIV prevention. PSIs were fabricated using a three-step process by (a) phase inversion of DTG-loaded polymer solution to form an initial in-situ forming implant in an aqueous solution, (b) micronization of dried DTG-loaded solid implants, and (c) compression of the micronized DTG-loaded solid implants to form the PSI. High drug loading (up to 85 wt%) was achieved in the PSIs. DTG exhibited minimum burst release in the first 24 h (<6%) and sustained release kinetics over 6 months. The release kinetics of DTG can be fine-tuned by varying drug-loading concentration, the ratio of polymer (poly(lactic-co-glycolic acid), PLGA) to solvent (N-methyl-2-pyrrolidone, NMP) and polymer (PLGA) molecular weight in the precursor solution. The physical/chemical properties of DTG were retained post-storage under accelerated storage conditions (40 °C/75% relative humidity) for 6 months. The versatility of this technology makes it an attractive drug delivery platform for HIV prevention applications.

Adolescent-Centered HIV Prevention: Perspectives on Acceptability of Oral Antiretroviral Pre-exposure Prophylaxis for Adolescents in a Global Priority Setting

With oral antiretroviral pre-exposure prophylaxis (PrEP) rollout expanding to include adolescents in South Africa, research is needed to better understand perceptions of PrEP acceptability among adolescents and clinical service providers. We conducted an exploratory mixed-methods study among 57 adolescents, 16-17 years of age, living with and without HIV, and 25 clinical service providers in Cape Town, South Africa from 2015 to 2016. Cross-sectional survey and semi-structured qualitative interview data were used to explore (1) willingness to use PrEP and support partner PrEP use among adolescents living with and without HIV, (2) willingness to prescribe or support prescription of PrEP among service providers, and (3) perceptions of barriers and facilitators to PrEP implementation and interpretations of PrEP efficacy messaging for adolescent HIV prevention among all participants. Acceptability of PrEP among participants was high. Support for PrEP uptake was linked to messages that positively framed PrEP's protection potential (i.e., success- versus failure-framed messaging) among both adolescents and providers. Adolescents living without HIV endorsed high willingness to use PrEP and adolescents living with HIV endorsed high support for partner PrEP use. However, both groups noted that potential side effects, stigma, and PrEP's partial efficacy may hinder uptake. Clinical service providers endorsed PrEP for sexually active adolescents and shared stigma and efficacy concerns. Further, service providers expressed desire for adolescent-tailored training and integration of PrEP delivery into primary care and family planning services. Efforts to educate adolescents and service providers about PrEP should consider how message framing may influence acceptability. Community PrEP education and adolescent-friendly delivery should be prioritized to alleviate predicted PrEP stigma and facilitate uptake.

Long-acting antiretrovirals: a new era for the management and prevention of HIV infection

The long-acting antiretroviral cabotegravir and rilpivirine combination has just received FDA, EMA and Health Canada approval. This novel drug delivery approach is about to revolutionize the therapy of people living with HIV, decreasing the 365 daily pill burden to only six intramuscular injections per year. In addition, islatravir, a first-in-class nucleoside reverse transcriptase translocation inhibitor, is intended to be formulated as an implant with a dosing interval of 1 year or more. At present, long-acting antiretroviral therapies (LA-ARTs) are given at fixed standard doses, irrespectively of the patient's weight and BMI, and without consideration for host genetic and non-genetic factors likely influencing their systemic disposition. Despite a few remaining challenges related to administration (e.g. pain, dedicated medical procedure), the development and implementation of LA-ARTs can overcome long-term adherence issues by improving patients' privacy and reducing social stigma associated with the daily oral intake of anti-HIV treatments. Yet, the current 'one-size-fits-all' approach does not account for the recognized significant inter-individual variability in LA-ART pharmacokinetics. Therapeutic drug monitoring (TDM), an important tool for precision medicine, may provide physicians with valuable information on actual drug exposure in patients, contributing to improve their management in real life. The present review aims to update the current state of knowledge on these novel promising LA-ARTs and discusses their implications, particularly from a clinical pharmacokinetics perspective, for the future management and prevention of HIV infection, issues of ongoing importance in the absence of curative treatment or an effective vaccine.

Interpersonal Violence and Contraceptive Method Use by Women Sex Workers

OBJECTIVE

More than one-half of women sex workers (sex workers) in the United States experience interpersonal violence, defined as physical or sexual violence, by sexual partners, including clients or intimate partners. Women experiencing interpersonal violence by intimate partners often choose hidden, woman-controlled contraception (e.g., intrauterine devices, pills, or sterilization) because fear of violence can impede condom negotiation. Yet, little is known about how interpersonal violence relates to contraception among sex workers who may have different sexual partner perpetrators (clients and intimate partners). The purpose of this study was to examine associations between interpersonal violence perpetrated by clients or intimate partners and contraceptive use.

STUDY DESIGN

Data are from an observational, prospective cohort of sex workers, aged 18 to 49 in Baltimore, Maryland (N = 218). Bivariate and multivariable logistic regression were used to assess associations between lifetime interpersonal violence and past 3-month contraceptive use. The outcome was any woman-controlled contraceptive use versus partner-controlled or no contraception.

RESULTS

Nearly all sex workers (96.5%) reported contraceptive use, with most using male condoms (69%), nearly one-half using woman-controlled methods (43%), and 25% using dual methods (e.g., condoms and a woman-controlled method). Lifetime experiences of interpersonal violence by clients (58%) and intimate partners (52%) were prevalent. Sex workers who experienced interpersonal violence by intimate partners had over twice the odds of woman-controlled contraceptive use (adjusted odds ratio, 2.48; 95% confidence interval, 1.36-4.54).

CONCLUSIONS

Findings highlight the importance of relationship context in the associations between interpersonal violence and use of woman-controlled contraceptive methods among sex workers, because only violence experiences by intimate partners were associated with increased odds of woman-controlled contraceptive method use.

Pharmacokinetic/pharmacodynamic investigation of raltegravir with or without lamivudine in the context of HIV-1 pre-exposure prophylaxis (PrEP)

Background

To characterize their potential use in pre-exposure prophylaxis (PrEP) we compared the pharmacokinetics of raltegravir and lamivudine in genital tissue against ex vivo tissue infection with HIV-1.

Methods

Open-label trial of 36 HIV-negative females and males randomized to 7 days raltegravir 400 mg twice daily and 7 days raltegravir 400 mg+lamivudine 150 mg twice daily (after washout), or vice versa. Blood, saliva, rectal fluid, rectal tissue, vaginal fluid and vaginal tissue were sampled at baseline and on and off PrEP during a total of 12 days, for pharmacokinetics and antiviral activity via ex vivo HIV-1_BaL challenge. Ex vivo infectivity was compared with baseline. The trial has been registered in https://clinicaltrials.gov/ with the identifier NCT03205566.

Results

Steady state for both drugs was reached by day 4. Dosing with raltegravir alone provided modest ex vivo HIV protection with higher drug levels in rectal tissue and vaginal tissue than in plasma on and off PrEP. Off PrEP, plasma and vaginal concentrations declined rapidly, while persisting in the rectum. On PrEP, the highest lamivudine concentrations were in the rectum, followed by vaginal tissue then plasma. Lamivudine washout was rapid in plasma, while persisting in the rectum and vagina. Raltegravir/lamivudine increased ex vivo protection on and off PrEP compared with raltegravir alone, reaching maximum protection at day 2 in rectal tissue and at day 8 in vaginal tissue.

Conclusions

Raltegravir 400 mg+lamivudine 150 mg showed high levels of ex vivo HIV protection, associated with high drug concentrations persisting after discontinuation in vaginal and rectal compartments, supporting further investigation of these agents for PrEP.