PrEP for HIV Prevention: Evidence, Global Scale-up, and Emerging Options

Perspectives on Design Approaches for HIV Prevention Efficacy Trials

The challenge of designing future HIV prevention efficacy trials in a rapidly evolving HIV prevention landscape was explored through a series of virtual stakeholder's engagement meetings convened online between October 2020 and April 2021. A broad array of stakeholders from the HIV prevention research community reviewed current trial designs and lessons learned, explored issues specific to unique product classes, and concluded with specialist-focused examinations of statistical design concepts and the importance of community engagement in research. The aim was to reflect on current approaches and evaluate new trial design approaches for evaluating efficacy of a candidate prevention strategy in the context of an active-controlled trial, which does not include a placebo arm. In this report, we provide a summary of the discussion points that included gaps in understanding and logical next steps in the prevention research pathway. The technical challenges involved in the statistical design approaches are described in a companion article.

The Effect of Disclosure of PrEP Use on Adherence Among African Young Women in an Open-Label PrEP Study: Findings from HPTN 082

To develop effective PrEP adherence interventions, it is important to understand the interplay between disclosure of pre-exposure prophalxis (PrEP) use, social support, and PrEP adherence. We leveraged the HPTN 082 study conducted among 451 adolescent girls and young women (AGYW) (ages 16 to 25 years, 2016 to 2019) in South Africa and Zimbabwe. Among the 349 who had month three disclosure and PrEP adherence data, 60% (n = 206) felt supported by adults, and 89% (n = 309) disclosed PrEP use to at least one person. PrEP disclosure was not associated with increased adherence, measured by intracellular tenofovir-diphosphate concentrations in dried blood spots. Women who reported having supportive adults, and disclosed to their parents, had higher adherence at 6 months with an increase of 177 fmol/punch (95% CI 12 to 343, t = 2.11, p = 0.04). PrEP interventions that help AGYW identify supportive relationships and effectively communicate the benefits of PrEP may improve PrEP adherence.Clinicaltrials.gov ID number: NCT02732730.

Assessing Per-Sex-Act HIV-1 Risk Reduction Among Women Using the Dapivirine Vaginal Ring

BACKGROUND

Confounding introduced by individuals' sexual risk behavior is potentially a significant source of bias in HIV-1 prevention intervention studies. To more completely account for sexual behaviors when assessing the efficacy of the monthly dapivirine ring, a new longer-acting HIV-1 prevention option for women, we estimated per-sex-act risk reduction associated with product use.

METHODS

We conducted a secondary analysis of data from MTN-020/ASPIRE, a phase 3, randomized, placebo-controlled efficacy trial of the dapivirine ring that recruited HIV-uninfected, African women aged 18-45 years. With cumulative sex acts as the time scale, we used multivariable Cox regression with inverse probability of censoring weights to estimate HIV-1 risk reduction associated with a rate of dapivirine release indicative of consistent product use.

RESULTS

Women in the dapivirine ring group (n = 1187) had an estimated incidence rate of 2.3 (95% confidence interval [CI], 1.8-3.1) HIV-1 acquisition events per 10 000 sex acts versus 3.6 (95% CI, 2.9-4.4) per 10 000 acts in the placebo group (n = 1187). Dapivirine release indicative of consistent ring use was associated with a 63% (95% CI, 33%-80%) per-sex-act HIV-1 risk reduction.

CONCLUSIONS

These results support the efficacy of the dapivirine vaginal ring for HIV-1 prevention and help to inform decision-making for women, providers, and policymakers regarding product use.

CLINICAL TRIALS REGISTRATION

NCT01617096.

Perceptions of Pre-exposure Prophylaxis (PrEP) for HIV prevention among men living with HIV in the context of reproductive goals in South Africa: a qualitative study

BACKGROUND

Pre-exposure Prophylaxis (PrEP) and Treatment as Prevention (TasP) are effective strategies to prevent HIV transmission within serodifferent couples. However, limited usage of PrEP, knowledge and interest has been amongst the barriers for men, alongside testing and treatment adherence. We explored the perceptions of PreP for HIV prevention with Men living with HIV (MWH) who have reproductive goals, to understand awareness and experiences related to PrEP use in the context of HIV prevention with their partners.

METHODS

We undertook a qualitative study with 25 MWH aged 18 to 65 between April and September 2021 in South Africa. Potential participants were screened for eligibility and scheduled to participate in telephonic interviews. Interviews were audio recorded, transcribed, translated and thematically analysed.

RESULTS

Themes were organized into opportunities and barriers that men with HIV articulate as important for using PrEP to meet individual, couple, and community reproductive goals. At the individual level, some men were willing to discuss PrEP with their partners to protect their partners and babies from acquiring HIV. Lack of knowledge about PrEP among men was a potential barrier to promoting PrEP among their female partners. At the couple level, PrEP use was seen as a way to strengthen relationships between partners, signifying care, trust, and protection and was seen as a tool to help serodifferent couples meet their reproductive goals safely. At the community level, PrEP was viewed as a tool to promote HIV testing and prevention efforts, especially among men, but participants emphasized the need for more education and awareness.

CONCLUSION

Despite PrEP implementation in South Africa, awareness of PrEP among men with HIV in rural areas remains low. Engaging MWH to support their partners in accessing PrEP could be an innovative strategy to promote HIV prevention. Additionally, providing men with comprehensive reproductive health information can empower them to make more informed decisions, adopt safer sexual practices, and challenge societal norms and stigmas around HIV.

Factors influencing the uptake of a mono-PrEP implant for the prevention of HIV: Males' perspectives from three South African provinces

INTRODUCTION

Oral pre-exposure prophylaxis (PrEP) is an effective HIV prevention method; however, males over 15 years face challenges with its effective use. Long-acting prevention products could address barriers to effective PrEP use. This study aimed to estimate the potential uptake of a mono-PrEP implant and the factors influencing uptake among males in South Africa. The study also examined messaging and demand creation tactics that males perceive will improve HIV prevention uptake.

METHODS

We conducted a mixed methods study comprising participatory workshops and a self-administered survey among 142 PrEP-eligible males (18-40 years) in three provinces (Gauteng, Eastern Cape, and Kwa-Zulu Natal) in South Africa from July to November 2022. Logistic regression was used to assess the relationship between the potential uptake of a hypothetical, non-biodegradable mono-PrEP implant and socioeconomic and behavioural factors. Workshop data were analysed using content analysis.

RESULTS

The top three HIV prevention products that males would consider using were the monthly pill (74.6%), the mono-PrEP implant (62.7%), and event-driven oral PrEP (59.2%). If one prevention option was available, 31.7% of participants stated that they would use the monthly oral pill, 28.2% would use the six-monthly injection, and 19.7% the mono-PrEP implant. Four key themes were noted as influential to potential mono-PrEP uptake: "Health Over Everything", "Mono-PrEP Implant Concerns", "Potential Disclosure of Mono-PrEP Use", and "Information Distribution Channels". Participants preferred social and mainstream media as information distribution channels to receive information on HIV prevention services, including the mono-PrEP implant.

CONCLUSION

In this study among predominantly heterosexual men in South Africa, there was interest in long-acting HIV prevention methods but concerns about the mono-PrEP implant. A comprehensive and participatory introduction will be needed for the implant, to improve acceptability and address potential concerns. Demand-creation strategies utilising social media and health campaigns should be considered to engage and reach males.

Efficacy estimates of oral pre-exposure prophylaxis for HIV prevention in cisgender women with partial adherence

Pre-exposure prophylaxis (PrEP) with tenofovir (TFV) disoproxil fumarate and emtricitabine administered orally daily is effective in preventing human immunodeficiency virus (HIV) acquisition in both men and women with sufficient adherence; however, the adherence-efficacy relationship in cisgender women has not been well established. We calculated the adherence-efficacy curve for cisgender women by using HIV incidence and plasma TFV concentration data from three trials (FEM-PrEP, VOICE and Partners PrEP). We imputed TFV diphosphate (TFV-DP) concentrations, a measure of long-term adherence, from TFV quantification by using data from the HIV Prevention Trials Network 082 study, which measured both TFV-DP and TFV concentrations. Two, four and seven pills per week reduced HIV incidence by 59.3% (95% credible interval (CrI) 29.9-95.8%), 83.8% (95% CI 51.7-99.8%) and 95.9% (95% CI 72.6-100%), respectively. Our adherence-efficacy curve can be validated and updated by HIV prevention studies that directly measure TFV-DP concentrations. The curve suggests that high adherence confers high protection in cisgender women. However, the lower efficacy with partial adherence highlights the need for new PrEP products and interventions to increase adherence.

Condomless Sex Among HIV-affected AYA in an Era of Undetectable = Untransmittable and Pre-exposure Prophylaxis

Given poor adherence to treatment and prevention techniques, condomless sex jeopardizes adolescents and young adults (AYA) with perinatally-acquired HIV-infection (PHIV) or perinatal HIV-exposure who are uninfected (PHEU). We examined condomless sex and its association with PHIV-status, psychiatric disorder, and sociodemographics. Data come from a US-based study of primarily Black and Latinx AYAPHIV and AYAPHEU (N = 340). Linear regression models examined condomless sex longitudinally by PHIV-status, psychiatric trajectories, and sociodemographics. Rates of viremia (AYAPHIV) and PrEP use (AYAPHEU) were assessed. 56% of participants reported recent condomless sex, with higher prevalence among: AYAPHEU vs. AYAPHIV (24% vs. 19%, p = 0.017); Latinx vs. non-Latinx AYA (25% vs. 17%, p = 0.014); and AYA with increasing psychiatric comorbidity (44%) and consistent anxiety (23%) vs. low-level disorder (17%; p < 0.05). AYAPHIV had high rates of unsuppressed viral load and AYAPHEU limited PrEP use. Preventing condomless sex is challenging within AYAPHIV and AYAPHEU. Developing accessible combination HIV/mental health interventions is much-needed.

PrEP uptake and early persistence among adolescent girls and young women receiving services via community and hybrid community-clinic models in Namibia

INTRODUCTION

Adolescent girls and young women (AGYW) face barriers in accessing clinic-based HIV pre-exposure prophylaxis (PrEP) services and community-based models are a proposed alternative. Evidence from such models, however, is limited. We evaluated PrEP service coverage, uptake, and early persistence among AGYW receiving services through community and hybrid models in Namibia.

METHODS

We analyzed routine data for AGYW aged 15-24 who initiated PrEP within HIV prevention programming. PrEP was delivered via three models: community-concierge (fully community-based services with individually-tailored refill locations), community-fixed (community-based initiation and refills delivered by community providers on a set schedule at fixed sites), and hybrid community-clinic (community-based initiation and referral to clinics for refills delivered by clinic providers). We examined proportions of AGYW engaged in services along a programmatic PrEP cascade, overall and by model, and assessed factors associated with PrEP uptake and early persistence (refill within 15-44 days after initiation) using multivariable generalized estimating equations.

RESULTS

Over 10-months, 7593 AGYW participated in HIV prevention programming. Of these, 7516 (99.0%) received PrEP education, 6105 (81.2%) received HIV testing services, 6035 (98.9%) tested HIV-negative, and 2225 (36.9%) initiated PrEP. Of the 2047 AGYW expected for PrEP refill during the study period, 254 (12.4%) persisted with PrEP one-month after initiation. Structural and behavioral HIV risk factors including early school dropout, food insecurity, inconsistent condom use, and transactional sex were associated with PrEP uptake. AGYW who delayed starting PrEP were 2.89 times more likely to persist (95% confidence interval (CI): 1.52-5.46) and those receiving services via the community-concierge model were 8.7 times (95% CI: 5.44-13.9) more likely to persist (compared to the hybrid model).

CONCLUSION

Community-based models of PrEP service delivery to AGYW can achieve high PrEP education and HIV testing coverage and moderate PrEP uptake. AGYW-centered approaches to delivering PrEP refills can promote higher persistence.

Equipping providers to offer novel MPTs: Developing counseling messages for the Dual Prevention Pill in clinical studies and beyond

Introduction

The pipeline for multi-purpose prevention technologies includes products that simultaneously prevent HIV, pregnancy and/or other sexually transmitted infections. Among these, the Dual Prevention Pill (DPP) is a daily pill co-formulating oral pre-exposure prophylaxis (PrEP), and combined oral contraception (COC). Clinical cross-over acceptability studies for the DPP require training providers to counsel on a combined product. From February 2021-April 2022, a working group of eight HIV and FP experts with clinical and implementation expertise developed counseling recommendations for the DPP based on existing PrEP/COC guidance.

Assessment of policy/guidelines options and implications

The working group conducted a mapping of counseling messages from COC and oral PrEP guidance and provider training materials. Six topics were prioritized: uptake, missed pills, side effects, discontinuation and switching, drug interactions and monitoring. Additional evidence and experts were consulted to answer outstanding questions and counseling recommendations for the DPP were developed. Missed pills was the topic with the most complexity, raising questions about whether women could "double up" on missed pills or skip the last week of the pack to recover protection faster. Uptake required aligning the time to reach protective levels for both DPP components and explaining the need to take DPP pills during week 4 of the pack. The potential intensity of DPP side effects, given the combination of oral PrEP with COC, was an important consideration. Discontinuation and switching looked at managing risk of HIV and unintended pregnancy when stopping or switching from the DPP. Guidance on drug interactions contended with differing contraindications for COC and PrEP. Monitoring required balancing clinical requirements with potential user burden.

Actionable recommendations

The working group developed counseling recommendations for the DPP to be tested in clinical acceptability studies. Uptake: Take one pill every day for the DPP until the pack is empty. Days 1-21 contain COC and oral PrEP. Days 22-28 do not contain COC to allow for monthly bleeding, but do contain oral PrEP and pills should be taken to maintain HIV protection. Take the DPP for 7 consecutive days to reach protective levels against pregnancy and HIV. Missed pills: If you miss 1 pill multiple times in a month or 2+ consecutive pills, take the DPP as soon as you remember. Do not take more than 2 pills in a day. If 2+ consecutive pills are missed, only take the last missed pill and discard the other missed pills. Side effects: You may experience side effects when you start using the DPP, including changes to monthly bleeding. Side effects are typically mild and go away without treatment. Discontinuation/switching: If you decide to discontinue use of the DPP, but want to be protected from HIV and/or unintended pregnancy, in most cases, you can begin using PrEP or another contraceptive method right away. Drug interactions: There are no drug-drug interactions from combining oral PrEP and COC in the DPP. Certain medications are not recommended due to their contraindication with oral PrEP or COC. Monitoring: You will need to get an HIV test prior to initiating or restarting the DPP, and every 3 months during DPP use. Your provider may recommend other screening or testing.

Discussion

Developing recommendations for the DPP as a novel MPT posed unique challenges, with implications for efficacy, cost, and user and provider comprehension and burden. Incorporating counseling recommendations into clinical cross-over acceptability studies allows for real-time feedback from providers and users. Supporting women with information to use the DPP correctly and confidently is critically important for eventual scale and commercialization.

Trust in the provider and accurate self-reported PrEP adherence among adolescent girls and young women in South Africa and Zimbabwe: HPTN 082 study

BACKGROUND

Trust is an important cornerstone of patient-provider communication. Accurate reporting of pre-exposure prophylaxis (PrEP) adherence is vital for providers to determine who needs adherence support, especially adolescent girls and young women (AGYW) disproportionately affected by newly diagnosed HIV.

METHODS

This is a secondary analysis of the HPTN 082 open-label PrEP demonstration trial. From 2016-2018, 451 AGYW aged 16-25 years were enrolled in South Africa (Cape Town and Johannesburg) and Zimbabwe (Harare). PrEP was initiated by 427, and 354 (83%) had month three patient-reported adherence responses and intracellular tenofovir diphosphate (TFV-DP) measurements. The patient-reported adherence response to 'In the past month, how often did you take the tablet?' was dichotomized as 'high' if the response was every day or most days, and 'low' if some days or not many days or never. The biomarker marker evidence of adherence in dried blood spots was defined as 'high' if TFV-DP ≥ 700, and 'low' if < 350 fmol/punch. We used multinomial logistic regression to examine if trust in the PrEP provider was associated with concordance between patient-reported adherence and intracellular tenofovir-diphosphate (TFV-DP).

RESULTS

AGYW who reported trust in their providers were almost four-fold (aOR 3.72, 95% CI 1.20-11.51) more likely to have concordant adherence (high self-reported adherence and high TFV-DP concentrations) compared to discordant non-adherence (high self-reported adherence and low TFV-DP concentrations).

CONCLUSION

Education and training of providers to build trusting relationships with AGYW may lead to more accurate reporting of PrEP adherence. With accurate reporting, adequate support can be provided to bolster adherence.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02732730.

Safety and efficacy of long-acting injectable cabotegravir as preexposure prophylaxis to prevent HIV acquisition

OBJECTIVE

HIV remains a significant burden, despite expanding HIV prevention tools. Long-acting injectable cabotegravir (CAB-LA) is a new preexposure prophylaxis (PrEP) product. We reviewed existing evidence to determine the efficacy and safety of CAB-LA as PrEP to inform global guidelines.

DESIGN

Systematic review and meta-analysis.

METHODS

We systematically reviewed electronic databases and conference abstracts for citations on CAB-LA from January 2010 to September 2021. Outcomes included HIV infection, adverse events, drug resistance, pregnancy-related adverse events, and sexual behavior. We calculated pooled effect estimates using random-effects meta-analysis and summarized other results narratively.

RESULTS

We identified 12 articles/abstracts representing four multisite randomized controlled trials. Study populations included cisgender men, cisgender women, and transgender women. The pooled relative risk of HIV acquisition comparing CAB-LA to oral PrEP within efficacy studies was 0.21 (95% confidence interval: 0.07-0.61), resulting in a 79% reduction in HIV risk. Rates of adverse events were similar across study groups. Of 19 HIV infections among those randomized to CAB-LA with results available, seven had integrase strand transfer inhibitor (INSTI) resistance. Data on pregnancy-related adverse events were sparse. No studies reported on sexual behavior.

CONCLUSIONS

CAB-LA is highly efficacious for HIV prevention with few safety concerns. CAB-LA may lead to an increased risk of INSTI resistance among those who have acute HIV infection at initiation or become infected while taking CAB-LA. However, results are limited to controlled studies; more research is needed on real-world implementation. Additional data are needed on the safety of CAB-LA during pregnancy (for mothers and infants) and among populations not included in the trials.

Psychosocial determinants of pre-exposure prophylaxis use among pregnant adolescent girls and young women in Cape Town, South Africa: A qualitative study

BACKGROUND

In South Africa, at least 7.5 million people (age ≥15 years) are living with Human Immunodeficiency Virus (HIV). In 2020, 220,000 new infections occurred, approximately one-third of which were among cisgender adolescent girls and women (age ≥15 years). The perspectives of pregnant adolescent girls and young women (AGYW) as key, targeted end-users of pre-exposure prophylaxis (PrEP) in this setting are not well known.

METHODS

We purposively recruited participants enrolled in an ongoing cohort study at an urban antenatal clinic in Cape Town, South Africa for in-depth interviews between July-September 2020. We restricted our analysis to pregnant AGYW (age: 16-25 years) who initiated daily oral PrEP (Tenofovir/Emtricitabine) antenatally and self-reported either high PrEP persistence (≥25 days in the past 30 days and no missed PrEP collection), or low PrEP persistence and/or discontinuation (missing >5 days in the last 30 days or missed PrEP collection). The findings were organized thematically, per the adapted Health Behavior Model (2000), using Nvivo-v.1.5.

RESULTS

We interviewed 18 AGYW (mean age = 22 years), at a mean of 14 weeks postpartum. Higher self-esteem and high-quality study provider-client relationships, including empathic psychosocial support, facilitated PrEP continuation. Reported barriers included unstable social structure characteristics (i.e., financial hardship) and individual factors (i.e., unintended pregnancy, parental rejection, and inadequate peer- and [non-cohabiting] partner support). Participants self-perceived a need for PrEP, feeling susceptible to non-consensual, forced sex, or considering partners' (presumed) sexual risk-taking. Limited community awareness regarding PrEP availability and/or perceived complexity in navigating health system access to PrEP, impede continuation.

CONCLUSIONS

PrEP-focused healthcare access pathways for pregnant and postpartum AGYW need to be simplified. Further research is needed on health system determinants (i.e., structural barriers, provider-client interactions, and related outcomes) of oral PrEP utilization. In 2022, South Africa announced regulatory approval of long-acting PrEP options (i.e., the dapivirine ring for non-pregnant women and injectable cabotegravir, respectively); these may mitigate implementation barriers reported in this study. However, the safety and efficacy of long-acting PrEP (e.g., injectables, implants) among pregnant or breastfeeding women, specifically, remains to be confirmed in this setting.

Quantifying and Predicting Ongoing Human Immunodeficiency Virus Type 1 Transmission Dynamics in Switzerland Using a Distance-Based Clustering Approach

BACKGROUND

Despite effective prevention approaches, ongoing human immunodeficiency virus 1 (HIV-1) transmission remains a public health concern indicating a need for identifying its drivers.

METHODS

We combined a network-based clustering method using evolutionary distances between viral sequences with statistical learning approaches to investigate the dynamics of HIV transmission in the Swiss HIV Cohort Study and to predict the drivers of ongoing transmission.

RESULTS

We found that only a minority of clusters and patients acquired links to new infections between 2007 and 2020. While the growth of clusters and the probability of individual patients acquiring new links in the transmission network was associated with epidemiological, behavioral, and virological predictors, the strength of these associations decreased substantially when adjusting for network characteristics. Thus, these network characteristics can capture major heterogeneities beyond classical epidemiological parameters. When modeling the probability of a newly diagnosed patient being linked with future infections, we found that the best predictive performance (median area under the curve receiver operating characteristic AUCROC = 0.77) was achieved by models including characteristics of the network as predictors and that models excluding them performed substantially worse (median AUCROC = 0.54).

CONCLUSIONS

These results highlight the utility of molecular epidemiology-based network approaches for analyzing and predicting ongoing HIV transmission dynamics. This approach may serve for real-time prospective assessment of HIV transmission.

Deep learning for topical trend discovery in online discourse about Pre-Exposure Prophylaxis (PrEP)

Pre-Exposure Prophylaxis (PrEP) interventions are increasingly prevalent on social media. These data can be mined for insights about PrEP that may not be as apparent in surveys including personal musings about PrEP and barriers/facilitators to PrEP uptake. This study explores online discourse about PrEP using an interdisciplinary public health and computational informatics approach. We collected (N = 4,020) tweets using Twitter's Application Programming Interface (API). These data underwent a three-step neural network/deep learning process to identify clusters within these tweets and relative similarity/dissimilarity between clusters. We identified 25 distinct clusters from our original collection of tweets. These clusters represent general information about PrEP, how PrEP is communicated among diverse groups, and potential pockets of misinformation and disinformation regarding PrEP. Specific clusters of interest include discussions of medication side effects, social perception of PrEP usage, and concerns with costs and barriers to access of PrEP interventions. Our approach revealed diverse ways PrEP is contextualized online. Importantly this information can be leveraged to identify points of possible intervention for disinformation and misinformation about PrEP.

Prevalence of sexualized drug use and risk of HIV among sexually active MSM in East and South Asian countries: systematic review and meta-analysis

INTRODUCTION

Sexualized drug use (SDU), the use of psychoactive drugs in the context of sexual intercourse, has been identified as a risk factor for HIV among men who have sex with men (MSM) in Asia. Given the distinct social and cultural context of same-sex relationships and drug-using practice in Asia, we aimed to describe the prevalence of SDU in East and South Asian countries and its associations with condomless anal sex (CAI) and HIV status. Synthesizing SDU research in this region, including SDU definitions, prevalence and outcomes, provides insights to inform future research and improved programme planning, resourcing and advocacy.

METHODS

We systematically searched OVID Medline, OVID EMBASE, OVID Global Health, CINAHL, PsycINFO and SCOPUS publication databases for scientific articles published from 1990 to 2022 measuring SDU among MSM in East and South Asian countries. A narrative synthesis was utilized to describe key study attributes and findings, and meta-analyses using random pooled effect models were used to estimate SDU prevalence and its associations with CAI and HIV status. Subgroup meta-analyses, sensitivity analysis and assessment of publication bias examined potential sources of heterogeneity for the pooled SDU prevalence estimates.

RESULTS AND DISCUSSION

Of the 1788 publications screened, 49 publications met the selection criteria and 18 were suitable for meta-analyses. Findings highlight SDU definitions distinct from other regions but inconsistencies in the definition of SDU between studies that have been highlighted in research elsewhere. The pooled prevalence of recent SDU (past 12 months) was 13% (95% CI = 10-16%; I2 = 97.6) but higher when studies utilized self-administered surveys (15%; 95% CI = 12-19%; p<0.05). SDU was associated with greater odds of CAI (pooled odds ratio [OR] = 3.21; 95% CI = 1.82-5.66) and living with diagnosed HIV (OR = 4.73; 95% CI = 2.27-8.21).

CONCLUSIONS

SDU is common among MSM in East and South Asian countries, but varying SDU definitions limit between-study comparisons. Responses to SDU-related harms should consider local contexts, including specific drug types used and their relative risks.

PrEP policy implementation gaps and opportunities in Latin America and the Caribbean: a scoping review

Background

Pre-exposure prophylaxis (PrEP) is an important tool for HIV prevention in Latin America and the Caribbean (LAC). Yet, little is known about the PrEP policies landscape in the region. Addressing this gap, this scoping review assessed current PrEP policies throughout LAC to better understand existing PrEP implementation gaps and identify opportunities to improve access.

Methods

We conducted a scoping review, using a modified PRISMA extension, through 28 July 2022, to identify country-level PrEP policies. Data were collected in English, Spanish, French, and Portuguese utilizing online platforms for screening and data extraction (Google Forms, Zotero, and Excel). Extracted data were divided by data source, including country-level government policies, gray literature, and peer-reviewed literature, with at least one full-text reviewer and data extractor per publication. An iterative summative content analysis was performed to compare and interpret themes across phases and data sources.

Results

Of the 33 countries in LAC, 22 (67%) had policies approving daily oral PrEP for HIV prevention, which outlined specific key populations, including men who have sex with men, transgender women, sex workers, and serodiscordant couples. Generic tenofovir disoproxil fumarate/emtricitabine has been approved in 15 of the 33 countries, and 13 of the 33 countries have incorporated PrEP into their public health system. No countries were found to have approved cabotegravir. Costing data were reported by only one country, Ecuador, in its national health ministry guidelines. Findings also document a lag between the media/gray-literature announcement of PrEP and implementation of policies.

Conclusion

Findings underscore significant advances in PrEP policies in the region and signal opportunities for greater PrEP implementation. Since 2017, an increasing number of countries have begun to provide PrEP to communities at heightened need, although significant gaps remain. Policy approval is a key step to further increasing access to PrEP in LAC, necessary to reduce the burden of HIV in LAC, specifically among marginalized populations.

Long-acting injectable cabotegravir for PrEP: A game-changer in HIV prevention?

BACKGROUND

Long-acting injectable cabotegravir (CAB-LA) represents a new additional option for HIV prevention in people at substantial risk of HIV infection that may fill the gaps in pre-exposure prophylaxis (PrEP) uptake, adherence, and retention in users having difficulty with oral PrEP. Data from clinical trials demonstrated that CAB-LA was safe, highly effective, and well-accepted for HIV prevention. However, the occurrence of breakthrough HIV infections despite timely injections, HIV seroconversion timing and patterns, risk of selection and dissemination of resistance-associated mutations to integrase inhibitors, complexity of follow-up, logistical considerations, and its cost effectiveness compared with oral PrEP constitute significant issues for the integration of CAB-LA into clinical routine.

FINDINGS

These concerns need to be addressed before moving forward with large-scale implementation programmes. Pilot and implementation projects are required in the following areas: HIV testing algorithms, patient education, clinic procedures, protocols for switching and discontinuation, efficacy and safety in populations not included in clinical trials, and demedicalization processes. The development of models to increase the uptake of, adherence to, and persistence with and after CAB-LA injections will also be of paramount importance for success. Lessons learned from these projects will increase experience, staff expertise, and organizational and training capacities to support the roll-out of this new agent as part of HIV prevention programmes.

CONCLUSION

CAB-LA has not yet achieved its full potential in HIV prevention, and strong commitment from all stakeholders is required to push CAB-LA as a game-changer in HIV response.

Acceptability of an intravaginal ring for simultaneously preventing HIV infection and pregnancy: Qualitative findings of the Kisumu Combined Ring Study, 2019

Multipurpose prevention technology intravaginal rings (MPT IVRs) may offer a promising solution for addressing women's multiple sexual and reproductive health needs. We describe MPT IVR acceptability perspectives and examine user experiences of 25 cisgender women aged 18-34 years enrolled in a phase IIa randomized, partially blinded, placebo-controlled evaluation of tenofovir-based IVRs with and without contraceptive co-formulation. All took part in an individual, audio-recorded, semi-structured qualitative interview. A thematic analysis of transcribed interviews was completed in MaxQDA. Participants shared little to no knowledge of or experience with IVRs prior to joining the study. Four MPT IVR themes were identified: physical well-being, method reliability, personal management, and societal endorsement. Commonly cited of concern, but less described as being experienced, were physical discomforts (e.g., painful insertion/removal; inability to carry out daily activities/chores; foreign body sensation; expulsion; sexual interference, or debilitating side effects). Uncertainty regarding efficacy influenced perspectives about intended prevention benefits. Personal choices in managing reproduction and sexual behaviors had to be congruent with sociocultural values and norms for acceptance beyond the individual user level. Participants viewed broader community acceptance as likely to be mixed given community opposition to the use of modern family planning methods. They also shared concerns that IVR use could lead to infertility, especially among nulliparous women, or that it would encourage premarital sex or high-risk sexual behaviors among adolescent and young women. While a MPT IVR may not be suitable for all women, first-hand testimonials could help influence collective receptivity. Additional community acceptability research is needed. Clinical Trial Registration The study is registered at http://ClinicalTrials.gov under the identifier NCT03762382.

Alignment of PrEP adherence with periods of HIV risk among adolescent girls and young women in South Africa and Zimbabwe: a secondary analysis of the HPTN 082 randomised controlled trial

BACKGROUND

Adolescent girls and young women in southern and eastern Africa have adherence challenges with daily oral HIV pre-exposure prophylaxis (PrEP). High adherence is most important during periods of HIV risk (prevention-effective adherence). We aimed to describe HIV risk behaviour and to understand patterns in PrEP adherence during periods of risk among adolescent girls and young women from sub-Saharan Africa.

METHODS

We did a secondary analysis of the HPTN 082 trial, an open-label, interventional, randomised controlled trial of sexually active adolescent girls and young women (aged 16-25 years) testing negative for HIV in Johannesburg and Cape Town, South Africa, and in Harare, Zimbabwe. The primary outcomes were high cumulative PrEP adherence, dichotomised as intracellular tenofovir diphosphate concentrations of at least 700 fmol/punch in dried blood spots at weeks 13, 26, and 52, and high recent PrEP adherence, dichotomised as plasma tenofovir concentrations of at least 40 ng/mL at weeks 13, 26, and 52, among participants who accepted PrEP. We collected data on sexual behaviour every 3 months. We categorised visits into a binary variable of any HIV risk based on condomless sex, more than one sexual partner, primary partner's HIV status and antiretroviral use, transactional sex, drug or alcohol use around sexual activity, and laboratory-diagnosed STIs. We used generalised estimating equations to evaluate associations between HIV risk (reflecting behaviour during the previous 3 months) and high cumulative and recent adherence to PrEP and any PrEP use (quantifiable drug concentrations). The trial is registered with ClinicalTrials.gov, NCT02732730.

FINDINGS

Between Oct 12, 2016, and Oct 25, 2018, 451 women were recruited, and 427 participants (median age 21·0 years [IQR 19·0-22·0]) were eligible for inclusion in this analysis. The proportion of participants reporting at least one HIV risk factor decreased significantly over follow-up, from 364 (85%) participants at enrolment, 226 (60%) at week 13, and 243 (65%) at week 26, to 224 (61%) at week 52 (p<0·0001). Any HIV risk was significantly associated with high PrEP adherence, measured by both tenofovir diphosphate concentrations of at least 700 fmol/punch (adjusted relative risk 1·57 [95% CI 1·09-2·25]; p=0·014) and plasma tenofovir concentrations of at least 40 ng/mL (1·36 [1·11-1·65]; p=0·0025). Any HIV risk was also associated with quantifiable concentrations of tenofovir diphosphate (1·15 [1·03-1·29]; p=0·013) and tenofovir (1·27 [1·09-1·49]; p=0·0022). We observed significant dose-response relationships between number of HIV risk factors and PrEP drug concentrations.

INTERPRETATION

The association between any HIV risk and high PrEP adherence suggests that adolescent girls and young women were able to use PrEP during periods of risk, an indicator of prevention-effective PrEP adherence. Our findings support a shift in the PrEP framework to acknowledge prevention-effective adherence practices, which might improve PrEP delivery and adherence support for adolescent girls and young women in HIV-endemic settings.

FUNDING

US National Institutes of Health.

Safety and Tolerability of Once Daily Coformulated Bictegravir, Emtricitabine, and Tenofovir Alafenamide for Postexposure Prophylaxis After Sexual Exposure

BACKGROUND

Antiretroviral post-exposure prophylaxis (PEP) is recommended to prevent HIV infection after a high-risk exposure, but current regimens have presented challenges in tolerability, regimen completion, and potential drug-drug interactions. Because coformulated bictegravir, emtricitabine, and tenofovir alafenamide [BIC/FTC/tenofovir alafenamide (TAF)] is effective for HIV treatment, it was evaluated for use for PEP.

SETTING

Boston community health center.

METHODS

Individuals accessing PEP were enrolled in an open-label study of coformulated BIC/FTC/TAF, taken as one pill daily for 28 days. Pearson's χ2 and Fisher's exact tests were used to assess whether BIC/FTC/TAF differed with respect to side effects and regimen completion rates compared with historical PEP regimens.

RESULTS

Between August, 2018 and March, 2020, 52 individuals enrolled in the study. Most identified as cisgender gay (67.3%) or bisexual (11.5%) men, but 7.7% identified as cisgender heterosexual men and 3.8% cisgender heterosexual women. The most common regimen side effects were nausea or vomiting (15.4%), fatigue (9.6%), and diarrhea/loose stools (7.7%), which were less common than historical controls using other PEP regimens, including those containing other integrase strand transfer inhibitors. Only 1 participant discontinued the regimen because of fatigue, and all other side effects were self-limited. Almost all participants (90.4%) completed the indicated regimen, which was a higher completion rate compared with earlier PEP regimens, and none became HIV-positive.

CONCLUSIONS

BIC/FTC/TAF coformulated as a single daily pill was found to be safe, well-tolerated, and highly acceptable when used for PEP, and compared more favorably than historical PEP regimens used at an urban health center.

Safety of G2-S16 Polyanionic Carbosilane Dendrimer as Possible HIV-1 Vaginal Microbicide

The UNAIDS objective for 2020 was 500,000 new HIV-1 infections per year; however, the latest annual reported data confirmed 1.7 million new HIV-1 infections in that year. Those data evidences the need for new prevention strategies and prophylactic treatments. This prevention crisis occurred in spite of the knowledge and availability of efficient prevention strategies. The G2-S16 is a microbicidal polyanionic carbosilane dendrimer currently being tested for topical vaginal application, which has been shown to be efficient in the prevention of HIV-1 infection. However, safety tests were lacked. For this purpose, we injected intravenously G2-S16 dendrimer to CD1 mice, thereby analyzing the hemogram, blood biochemical markers of systemic damage, accumulation in the organs and organ-tissue damage in heart, spleen, kidney, liver and brain. This work shows that even if the G2-S16 dendrimer penetrates the epithelial tissue, it does not cause vaginal irritation or tissue damage. Moreover, the i.v. injection of the G2-S16 dendrimer did not cause a damaging effect on the studied organs and it did not modify the hemogram or the biochemical plasma markers. In conclusion, the G2-S16 dendrimer has a very good safety profile, indicating that this molecule can be a very safe and efficient vaginal microbicide.

Introducing the Dapivirine Vaginal Ring in Sub-Saharan Africa: What Can We Learn from Oral PrEP?

Purpose of review

Clinical trials have found that the dapivirine vaginal ring (DVR) is safe to use and effective at reducing women’s risk of acquiring HIV infection. As countries prepare for the introduction of this novel long-acting, woman-controlled prevention method, an examination of key learnings from oral pre-exposure prophylaxis (PrEP) delivery will help programs leverage successful innovations and approaches to support DVR scale-up and expand the method mix for HIV prevention.

Recent findings

Intensive efforts over the past 5 years have yielded lessons on how to facilitate access to oral PrEP; expand service delivery for PrEP; address the knowledge, attitudes, and skills providers need to support PrEP initiation and effective use; develop messaging that builds community and partner support and combats stigma; and understand the cyclical nature of PrEP use.

Summary

Evidence from oral PrEP introduction and scale-up can help inform and expedite DVR introduction.

The wisdom of mistrust: qualitative insights from transgender women who participated in PrEP research in Lima, Peru

INTRODUCTION

Although pre-exposure prophylaxis (PrEP) is a remarkable biomedical advance to prevent HIV, ongoing research on PrEP contributes to and interacts with a legacy of HIV experimentation on marginalized communities in resource-limited settings. This paper explores the complexity of PrEP research mistrust among Peruvian transgender (trans) women who completed a PrEP adherence intervention and those who refused participation (i.e. declined to enrol, voluntarily withdrew, and/or were lost to follow-up).

METHODS

Data were derived from 86 trans women (mean age 29 years) participants in the formative (four focus groups (n = 32), 20 interviews) and the evaluation stages (34 interviews) of a social network-based PrEP intervention for trans women in Lima, Peru. The formative stage took place from May to July 2015, while the evaluative stage took place from April to May 2018. Audio files were transcribed verbatim and analysed via an immersion crystallization approach using Dedoose (v.6.1.18).

RESULTS

Three paradoxes of trans women's participation in PrEP science as a "key" population emerged as amplifying mistrust: (1) increases in PrEP research targeting trans women but limited perceived improvements in HIV outcomes; (2) routine dismissal by research physicians and staff of PrEP-related side effects and the social realities of taking PrEP, resulting in questions about who PrEP research is really for and (3) persistent limitations on PrEP access for trans women despite increasing involvement in clinical trials, fostering feelings of being a "guinea pig" to advance PrEP science.

CONCLUSIONS

Findings highlight the wisdom inherent in PrEP mistrust as a reflection of trans women's experiences that underscore the broken bonds of trust between communities, researchers and the research enterprise. PrEP mistrust is amplified through perceived paradoxes that suggest to trans women that they are key experimental participants but not target PrEP users outside of research settings. Findings highlight the urgent need to reframe mistrust not as a characteristic of trans women to be addressed through education and outreach, but as a systemic institutional- and industry-level problem replicated, manifested and ultimately to be corrected, through global HIV science.

High Levels of Prevention-Effective Adherence to HIV PrEP: An Analysis of Substudy Data From the EPIC-NSW Trial

BACKGROUND

Preexposure prophylaxis (PrEP) prevents HIV infection but relies on good adherence at times of risk, termed "prevention-effective adherence." Most studies assess adherence without reference to sexual behaviur, making it challenging to determine if poor adherence coincides with HIV risk.

SETTING

We examined data from a behavioral substudy of a large-scale PrEP implementation trial in New South Wales, Australia.

METHODS

Trial participants completed optional brief quarterly surveys, reporting the number of pills taken and sexual behavior with male partners for each day of the "last full week" before each survey. Condomless sex (CLS) was defined as "higher risk" for HIV when with HIV-positive men with detectable/unknown viral loads or unknown HIV status men. Adequate PrEP protection was defined as ≥4 pills for participants assigned male sex at birth and ≥6 pills for participants assigned female sex at birth (including transgender men).

RESULTS

Of 9596 participants dispensed PrEP, 4401 completed baseline and ≥1 follow-up survey. Participants reported on 12,399 "last full weeks": 7485 weeks (60.4%) involved CLS and 2521 weeks (33.7% of CLS-weeks) involved higher risk CLS. There were 103 weeks in which participants did not have adequate PrEP protection and had higher risk CLS: 4.1% of higher-risk CLS weeks (n = 103/2521), 1.4% of all CLS weeks (n = 103/7485), and 0.8% of all observed weeks (n = 103/12,399).

CONCLUSIONS

In a large PrEP trial, prevention-effective adherence to PrEP was very high at 99%. Our findings illustrate the importance of measuring pill-taking and sexual behavior in the same period so that prevention-effective adherence can be better estimated.

Use of simulated vaginal and menstrual fluids to model in vivo discolouration of silicone elastomer vaginal rings

Vaginal rings releasing antiretrovirals – either alone or in combination with contraceptive progestins – are being developed for prevention of human immunodeficiency virus (HIV) transmission via vaginal sex. Following Phase I trials, significant discolouration was observed on the surface of investigational silicone elastomer antiretroviral-contraceptive matrix-type vaginal rings containing either 25 mg dapivirine or 200 mg dapivirine plus levonorgestrel. In this study, potential causes of the discolouration have been assessed in vitro using simulated vaginal and menstrual fluids (SVF and SMF, respectively) to model in vivo exposure. The fluid compositions also included hydrogen peroxide (H₂O₂), hydrogen peroxide plus a copper intrauterine device (IUD), or synthetic dyes (representing personal care and household cleaning products). No discolouration was observed for rings exposed to SVF + hydrogen peroxide (with or without an IUD). However, the SVF + dye compositions showed significant ring discolouration, with staining patterns similar to those observed with rings that had been exposed to highly-coloured personal care and household cleaning products during clinical trial use. Exposure of rings to SMF compositions invariably caused yellow surface discolouration, dark spotting and markings, similar to the staining patterns observed following clinical use. The darker marks on the ring surface were identified as blood debris derived from the SMF. The study indicates that surface discolouration of rings in vivo can be attributed to exposure to menstrual fluid or highly coloured personal care or household cleaning products. Discolouration of the rings was not associated with any specific safety risks for the user, though severe discolouration could potentially impact acceptability and adherence.

Inflammatory cytologic alterations in the oral epithelium associated with HIV pre-exposure prophylaxis: a preliminary study

OBJECTIVE

The objective of this study was to assess inflammatory cytologic alterations in the oral epithelium of patients on human immunodeficiency virus pre-exposure prophylaxis (PrEP).

MATERIAL AND METHODS

Epithelial cells from the buccal mucosa of 30 patients were collected by exfoliative cytology and were evaluated according to inflammatory cellular alterations: karyomegaly, bi- or multinucleation, karyopyknosis, karyorrhexis, perinuclear halo formation, metachromasia, cytoplasmic vacuolization, indistinct cytoplasmic border, keratinization, and atrophy. Epithelial cells were collected initially before PrEP onset (T1) and then after 30 days of PrEP use (T2). Two experienced cytopathologists independently analyzed the slides.

RESULTS

The nonparametric Wilcoxon test showed that there was a statistically significant increase in the number of cells with karyomegaly at T2 compared to T1 (P = .033). The other cellular alterations did not present with statistically significant differences between the 2 moments of evaluation (P > .05).

CONCLUSION

The increased number of oral epithelial cells with karyomegaly after 30 days of using PrEP suggests the presence of inflammatory alterations at this site.