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

A selective, sensitive and fast LC-MS/MS method for cabotegravir quantification in rat plasma and pharmacokinetic investigations

This study presents a novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for quantifying cabotegravir (CAB) in rat plasma. A novel, sensitive, and rapid LC-MS/MS method has been developed and validated. Furthermore, protein precipitation technique allowed us to lowered the limit of quantification (LOQ) to nanogram levels, allowing detection of smaller CAB amounts in plasma samples. A review of scientific literature reveals that this method is superior than published methods in terms of runtime, sensitivity, wide linearity, and cost, using LC-MS/MS to quantify CAB in biological samples. CAB reached its maximum concentration (Cmax) of 78.401 μg/mL in rat plasma at 1.50 h (Tmax). Linearity was evaluated across 0.05-1000 μg/mL for CAB using five calibration curves with at least nine standards each with r2 > 0.9997. The intra- and inter-day precision and accuracy results were below 15% and acceptable as per Food and Drug Administration (FDA) guidelines. Stability of compounds were established in a battery of stability studies, that is, benchtop, autosampler, and long-term storage stability as well as freeze thaw cycles. The validated method can be used as a routine method to support pharmacokinetic studies.

Examining concordance of sexual-related factors and PrEP eligibility with HIV risk perception among adolescent girls and young women: cross-sectional insights from DREAMS sites in Kenya, Malawi, and Zambia

BACKGROUND

HIV risk perception is an important cognition for prevention, theoretically engendering service-seeking and risk-reduction behaviors, but its composition remains poorly understood. We examined country-specific correlates of self-appraised HIV exposure risk among sexually active adolescent girls and young women (AGYW, aged 15-24 years) without HIV in Kenya, Malawi, and Zambia. We also explored overlaps between self-appraised HIV exposure risk and pre-exposure prophylaxis (PrEP) eligibility to identify engagement opportunities.

METHODS

We analyzed cross-sectional data (2016/2017) to estimate sexual-related correlates of self-appraised HIV exposure risk (likely vs. not, temporally framed as "ever") using log-Poisson models with robust standard errors. For sexual-related factors with an unadjusted p ≤ 0.10, individual adjusted models were fitted, controlling for sociodemographic and cognitive factors with an unadjusted p ≤ 0.10. PrEP eligibility was defined using national guidelines; since conditional criteria are in Malawi's (age-disparate sex + ever-pregnant) and Zambia's (multiple partners + condomless sex) guidelines, we also assessed PrEP eligibility after decoupling these factors.

RESULTS

Few AGYW reported likely HIV exposures (Kenya [N = 746]: 15.7%, Malawi [N = 1348]: 46.2%, Zambia [N = 349]: 9.5%) despite ubiquitous HIV risk (98.7%, 99.8%, and 98.9% of Kenyan, Malawian, and Zambian AGYW reported ≥ 1 sexual-related factor). However, the adjusted models found some actual-perceived risk concordance. Positive correlates of self-appraised likely HIV exposures included partner(s)' likely HIV exposure (all countries); partner(s)' unknown HIV status and other partners (Kenya, Malawi); STI symptoms and partner(s) living outside the community (Kenya); non-partner sexual violence (Zambia); and transactional sex, multiple partners, pre-coital alcohol use, and physical/sexual intimate partner violence (Malawi). Per national guidelines, PrEP eligibility criteria differentially identified HIV risk (Kenya: 93.6%, Malawi: 53.3%, Zambia: 44.6%), and self-appraised likely HIV exposures were low among PrEP-eligible AGYW (Kenya: 16.5%, Malawi: 48.5%, Zambia: 18.8%). Decoupling Malawi's and Zambia's conditional PrEP criteria could increase risk identification to > 85% and potential engagement by ~ 70% and ~ 30%, respectively.

CONCLUSIONS

AGYW's HIV risk perceptions were mostly influenced by factors beyond their locus of control. Conditional PrEP eligibility criteria may inhibit AGYW's access and uptake in some settings: countries should consider decoupling these factors to minimize barriers. Intersections between autonomy, behaviors, and perceptions among AGYW in gender-inequitable settings warrants further investigation.

Assessing Preferences for Long-Acting Injectable Pre-Exposure Prophylaxis Among Young Adult Sexual Minority Men and Transgender Women

OBJECTIVE

Oral pre-exposure prophylaxis (PrEP) is effective in preventing HIV transmission. However, oral PrEP uptake is low, particularly among sexual and gender minority youth who are vulnerable to HIV infection. Alternative methods of PrEP delivery, such as long-acting injectable (LAI) PrEP may overcome barriers and be preferred. However, attitudes and preferences of younger sexual and gender minorities towards LAI PrEP have not been well studied. The purpose of this study is to describe preferences for initiating LAI PrEP among sexual and gender minority youth.

METHODS

We analyzed data collected as part of an HIV prevention randomized trial from January 2022 to February 2023, using multiple regression to identify factors associated with a preference for LAI PrEP.

RESULTS

The study sample (N = 265) was 50% youth of color, mean age 25 years (SD=3.4, range=18-31), and primarily identified as gay (71%) and male (91%). Forty two percent had heard of LAI PrEP and 31% preferred LAI PrEP over other prevention methods. In multiple regression analysis, LAI PrEP preference was associated with identifying as White, previous PrEP experience, and perceived LAI PrEP efficacy.

CONCLUSIONS

We conclude that gaps in awareness exist for LAI PrEP, however it may be preferred over other prevention methods especially in White youth, those with PrEP experience and higher perceptions of its efficacy. More education and outreach are needed to prevent extension of existing race and ethnicity disparities in use of oral daily PrEP to LAI PrEP.

Telehealth Models for PrEP Delivery: A Systematic Review of Acceptability, Implementation, and Impact on the PrEP Care Continuum in the United States

Pre-exposure prophylaxis (PrEP) is pivotal in curbing HIV transmission and is integral to the national plan to end the HIV epidemic in the United States (US). Nonetheless, widespread PrEP adoption faces barriers. Telehealth delivery models for PrEP, or telePrEP, can enhance PrEP access and adherence by providing flexible care remotely. This study presents a systematic review of telePrEP programs in the US, aiming to describe model characteristics and summarize clinical, implementation, and equity outcomes. We reviewed studies published from 2012 to 2023. We included articles that described telePrEP systems in the US and measured PrEP care continuum outcomes (awareness, initiation, uptake, adherence) or acceptability of the intervention by program users. Eight articles describing six distinct telePrEP initiatives met our inclusion criteria. Studies described models implemented in community-based, academic, and commercial settings, with most programs using a direct-to-client telePrEP model. Across studies, clients reported high acceptability of the telePrEP programs, finding them easy to use, convenient, and helpful as a tool for accessing HIV prevention services. No programs were offering injectable PrEP at the time these studies were conducted. Data was limited in measuring PrEP retention rates and the reach of services to underserved populations, including Black and Latinx communities, transgender individuals, and cis-gender women. Findings underscore the potential of telePrEP to bolster the reach of PrEP care and address structural barriers to access. As telehealth models for PrEP care gain prominence, future research should concentrate on refining implementation strategies, enhancing equity outcomes, and expanding services to include injectable PrEP.

Pre-exposure prophylaxis (PrEP) use trajectories and incidence of HIV and other sexually transmitted infections among PrEP users in Belgium: a cohort analysis of insurance claims data from 2017 to 2019

BACKGROUND

Since June 2017, oral pre-exposure prophylaxis (PrEP) has been reimbursed in Belgium for people at substantial risk of HIV. To inform the national PrEP programme, we described sociodemographic characteristics of PrEP users, PrEP dispensing practices, testing for HIV and sexually transmitted infections (STIs; gonorrhoea, chlamydia and syphilis), and incidence of HIV and STIs.

METHODS

Analysis of routinely collected social health insurance claims data from all individuals who were dispensed at least one PrEP prescription between June 2017 and December 2019. Using logistic regression adjusted for age, we examined associations between sociodemographic characteristics and having been dispensed PrEP only once in the first six months of PrEP use.

RESULTS

Overall, 4559 individuals were dispensed PrEP. Almost all PrEP users were male (99.2%, 4522/4559), with a median age of 37 years (IQR 30-45). A minority were entitled to an increased healthcare allowance (11.4%, 514/4559). 18% (657/3636) were dispensed PrEP only once in the first six months of PrEP use. PrEP users younger than 25 years, unemployed, entitled to an increased healthcare allowance, and who initiated PrEP between January 2019 and June 2019 were more likely to have had no PrEP dispensing after initiation compared to their counterparts. The testing rates for bacterial STIs and HIV were 4.2 tests per person-year (95% CI 4.1-4.2) and 3.6 tests per person-year (95% CI 3.5-3.6), respectively. Twelve individuals were identified to have seroconverted during the study period, resulting in an HIV incidence rate of 0.21/100 person-years (95% CI 0.12-0.36). The incidence of bacterial STIs was 81.2/100 person-years (95% CI 78.7-83.8).

CONCLUSIONS

The study highlights challenges in PrEP persistence and a high incidence of bacterial STIs among individuals receiving PrEP. Tailored prevention support is crucial for individuals with ongoing HIV risk to optimise PrEP effectiveness. Integrated STI testing and prevention interventions within PrEP care are necessary to mitigate STI acquisition and transmission among PrEP users.

Systemic delivery of bictegravir and tenofovir alafenamide using dissolving microneedles for HIV preexposure prophylaxis

Human immunodeficiency virus (HIV) continues to pose a serious threat to global health. Oral preexposure prophylaxis (PrEP), considered highly effective for HIV prevention, is the utilisation of antiretroviral (ARV) drugs before HIV exposure in high-risk uninfected individuals. However, ARV drugs are associated with poor patient compliance and pill fatigue due to their daily oral dosing. Therefore, an alternative strategy for drug delivery is required. In this work, two dissolving microneedle patches (MNs) containing either bictegravir (BIC) or tenofovir alafenamide (TAF) solid drug nanoparticles (SDNs) were developed for systemic delivery of a novel ARV regimen for potential HIV prevention. According to ex vivo skin deposition studies, approximately 11% and 50% of BIC and TAF was delivered using dissolving MNs, respectively. Pharmacokinetic studies in Sprague Dawley rats demonstrated that BIC MNs achieved a long-acting release profile, maintaining the relative plasma concentration above the 95% inhibitory concentration (IC95) for 3 weeks. For TAF MNs, a rapid release of drug and metabolism of TAF into TFV were obtained from the plasma samples. This work has shown that the proposed transdermal drug delivery platform could be potentially used as an alternative method to systemically deliver ARV drugs for HIV PrEP.

Need for informed providers: exploring LA-PrEP access in focus groups with PrEP-indicated communities in Baltimore, Maryland

BACKGROUND

The approval of long-acting pre-exposure prophylaxis PrEP (LA-PrEP) in the United States brings opportunities to overcome barriers of oral PrEP, particularly among sexual and gender minority communities who bear a higher HIV burden. Little is known about real-time decision-making among potential PrEP users of LA-PrEP post-licensure.

METHODS

We held focus group discussions with people assigned male at birth who have sex with men in Baltimore, Maryland to explore decision-making, values, and priorities surrounding PrEP usage. A sexual and gender minority-affirming health center that provides PrEP services supported recruitment. Discussions included a pile-sorting activity and were audio-recorded. Recordings were transcribed and analyzed iteratively, combining an inductive and deductive approach.

RESULTS

We held five focus groups from Jan-June 2023 with 23 participants (21 cisgender men who have sex with men, two transgender women who have sex with men; mean age 37). Among participants, 21 were on oral PrEP, one was on injectable PrEP, and one had never taken PrEP. Most had never heard about LA-PrEP. When making decisions about PrEP, participants particularly valued efficacy in preventing HIV, side effects, feeling a sense of security, and ease of use. Perceptions varied between whether oral or injectable PrEP was more convenient, but participants valued the new opportunity for a choice in modality. Factors influencing PrEP access included cost, individual awareness, provider awareness, and level of comfort in a healthcare environment. Participants emphasized how few providers are informed about PrEP, placing the burden of being informed about PrEP on them. Comfort and trust in a provider superseded proximity as considerations for if and where to access PrEP.

CONCLUSIONS

There is still low awareness about LA-PrEP among sexual and gender minority communities; thus, healthcare providers have a critical role in influencing access to LA-PrEP. Despite this, providers are still vastly underinformed about PrEP and underprepared to support clients in contextualized ways. Clients are more likely to engage in care with affirming providers who offer non-judgmental conversations about sex and life experiences. Provider education in the United States is urgently needed to better support clients in choosing a PrEP modality that is right for them and supporting adherence for effective HIV prevention.

Long-acting cabotegravir pharmacokinetics with and without oral lead-in for HIV PrEP

Long-acting cabotegravir is approved for pre-exposure prophylaxis and combination HIV treatment, both initiated with optional short-term oral lead-in (OLI). We evaluated the impact of OLI on long-acting cabotegravir pharmacokinetics. Cabotegravir plasma concentrations were compared between HIV-positive participants initiating injections with (n = 278) or without (n = 110) OLI in phase III treatment study FLAIR and in HIV-negative participants using OLI (n = 263) in pivotal pre-exposure prophylaxis studies HPTN 083 and HPTN 084. Cabotegravir pharmacokinetic profiles were simulated in three populations (assigned-male-at-birth, 50%-assigned-female-at-birth, and assigned-female-at-birth) under three scenarios: first injection given (A) 1 or (B) 3 days after final OLI dose (OLI-injection gap) or (C) without OLI. The PK objective was 80% of participants achieving 4× in vitro protein-adjusted 90% maximal inhibitory concentration (PA-IC90) and 50% achieving 8× PA-IC90. Observed trough concentrations (Cτ) were similar with and without OLI (P > 0.3). With a 3-day OLI-injection gap, simulated pre-injection Cτ remained above PK objective. Approximately 1-2 weeks after the first injection, simulated PK profiles became nearly identical among all scenarios. Without OLI, it was predicted that 80% of participants achieve 4× PA-IC90 in 1.2, 1.8, and 2.8 days after the first injection in each population, respectively, and 50% achieve 8× PA-IC90 in 1.4, 2.1, and 3.8 days, respectively. Observed long-acting cabotegravir exposure was similar with or without OLI, supporting optional OLI use. Cabotegravir exposure was predicted to remain above PK objective for OLI-injection gaps of ≤3 days and rapidly achieve PK objective after first injection without OLI. Findings are consistent between assigned-male-at-birth and assigned-female-at-birth populations.This study is registered with ClinicalTrials.gov as NCT02720094.

Perspectives on Injectable HIV Pre-Exposure Prophylaxis: A Qualitative Study of Health Care Providers in the United States

The introduction of injectable HIV pre-exposure prophylaxis (PrEP) has the potential to significantly change the biomedical HIV prevention landscape. However, effective implementation will require health care providers to adopt, prescribe, and administer injectable PrEP within clinical settings. This study qualitatively examined challenges and benefit of injectable PrEP implementation from the perspective of health care providers. From April to August 2022, we conducted 19 in-depth interviews with current PrEP-prescribing health care providers in New York State, including 3 physician assistants, 5 physicians, and 11 nurse practitioners. Interviews were audio-recorded, transcribed verbatim, and thematically analyzed to report semantic-level themes regarding injectable PrEP implementation. More than half of participants (61%) were aware of injectable PrEP; only 21% had experience prescribing it. Qualitative findings highlighted five themes. Three themes represented implementation challenges, including speculative concerns about side effects, appointment compliance, and practical and logistical considerations. The remaining two themes described benefits of injectable PrEP relative to oral PrEP, which included greater convenience and enhanced privacy. Findings from this qualitative study make significant applied contributions to the sparse knowledge on health care provider perspectives of injectable PrEP post-US Food and Drug Administration approval and their concerns and considerations regarding implementation in real-world clinical settings.

HIV pre-exposure prophylaxis services, provision, and delivery in the European treatment network of HIV, hepatitis and global emerging infectious diseases (NEAT ID)

OBJECTIVES

We conducted a survey to evaluate HIV pre-exposure prophylaxis (PrEP) practices in a European clinical research network on HIV, hepatitis, and global infectious diseases (NEAT ID).

METHODS

An online survey comprising 22 questions was sent via a secure electronic tool to the investigating physician of each of the 342 NEAT ID study centres across 15 European countries in November 2020.

RESULTS

In total, 50 sites from 12 countries responded (15% response rate). Most sites were in Western Europe, two were in Poland, and one was in Hungary. Of the responding sites, 45 provided PrEP services for a total of 27 416 PrEP users, with 1361 new PrEP initiators each month. These centres supplied PrEP for men who have sex with men (100%), people who inject drugs (84%), sex workers (84%), women (62%), and transgender women (31%). PrEP persistence after 1 year was >90%, 75%-90%, and 40%-75% in 17, 24, and 4 centres, respectively. In total, 32/45 (71%) centres reported strong community-based organization commitment at their site, and 15/45 (33%) centres developed task-shifting processes to deliver PrEP through nurses (11/15), pharmacists (5/15), and key-population peers (2/15). The biggest barriers to implementation of PrEP were low awareness of and knowledge about PrEP (47%), unwillingness to disclose sexual identity or at-risk behaviour (36%), and lack of administrative support (29%). Of the 45 centres, 32 (71%) have already been involved in PrEP research and 43 (96%) were interested in participating in such studies.

CONCLUSIONS

The few NEAT ID centres that responded to the survey showed disparities in PrEP deployment and practices despite a common interest in participating in research in this field.

Adolescents and young adults are the most undiagnosed of HIV and virally unsuppressed in Eastern and Southern Africa: Pooled analyses from five population-based surveys

Age and gender disparities within the HIV cascade of care are critical to focus interventions efficiently. We assessed gender-age groups at the highest probability of unfavorable outcomes in the HIV cascade in five HIV prevalent settings. We performed pooled data analyses from population-based surveys conducted in Kenya, South Africa, Malawi and Zimbabwe between 2012 and 2016. Individuals aged 15-59 years were eligible. Participants were tested for HIV and viral load was measured. The HIV cascade outcomes and the probability of being undiagnosed, untreated among those diagnosed, and virally unsuppressed (≥1,000 copies/mL) among those treated were assessed for several age-gender groups. Among 26,743 participants, 5,221 (19.5%) were HIV-positive (69.9% women, median age 36 years). Of them, 72.8% were previously diagnosed and 56.7% virally suppressed (88.5% among those treated). Among individuals 15-24 years, 51.5% were diagnosed vs 83.0% among 45-59 years, p<0.001. Among 15-24 years diagnosed, 60.6% were treated vs 86.5% among 45-59 years, p<0.001. Among 15-24 years treated, 77.9% were virally suppressed vs 92.0% among 45-59 years, p<0.001. Among all HIV-positive, viral suppression was 32.9% in 15-24 years, 47.9% in 25-34 years, 64.9% in 35-44 years, 70.6% in 45-59 years. Men were less diagnosed than women (65.2% vs 76.0%, p <0.001). Treatment among diagnosed and viral suppression among treated was not different by gender. Compared to women 45-59 years, young people had a higher probability of being undiagnosed (men 15-24 years OR: 37.9, women 15-24 years OR: 12.2), untreated (men 15-24 years OR:2.2, women 15-24 years OR: 5.7) and virally unsuppressed (men 15-24 years OR: 1.6, women 15-24 years OR: 6.6). In these five Eastern and Southern Africa settings, adolescents and young adults had the largest gaps in the HIV cascade. They were less diagnosed, treated, and virally suppressed, than older counterparts. Targeted preventive, testing and treating interventions should be scaled-up.

Prevention strategies for sexually transmitted infections, HIV, and viral hepatitis in Europe

The current prevention efforts for STIs, HIV and viral hepatitis in the WHO European Region, especially in the Central and Eastern subregions, are hindered by healthcare disparities, data gaps, and limited resources. In this comprehensive narrative review, we aim to highlight both achievements and persisting challenges while also exploring new developments that could significantly impact the prevention of these infections in the near future. While pre-exposure prophylaxis (PrEP) for HIV has been broadly approved and implemented in 38 out of 53 countries in the region, challenges remain, including cost, limited licensing, and incomplete adherence. We explore innovative approaches like on-demand PrEP, long-acting injectable cabotegravir, and intravaginal rings that have shown promising results, alongside the use of six-monthly lenacapavir, the outcomes of which are pending. Additionally, the potential of doxycycline post-exposure prophylaxis has been discussed, revealing efficacy in reducing chlamydia and syphilis risk, but effectiveness against gonorrhoea being contingent on tetracycline resistance rates, and the need of further data to determine potential resistance development in other bacteria and its impact on the gut microbiome. We examine successful vaccination campaigns against HBV and HPV, the ongoing development of vaccines for chlamydia, syphilis, herpesvirus, and gonorrhoea, and challenges in HIV vaccine research, including lines of research with significant potential like sequential immunization, T-cell responses, and mRNA technology. This review underscores the research endeavors that pave the way for a more resilient and robust approach to combating STIs, HIV, and viral hepatitis in the region.

Evolution of Antiretroviral Drug Rilpivirine and Approach to Oncology

Rilpivirine is an antiretroviral drug used to treat AIDS worldwide. The drug is a non-nucleoside reverse transcriptase inhibitor that halts the cDNA elongation process and, thus, the capacity of the HIV-1 virus to replicate. With the new wave of drug repurposing in recent years, rilpivirine has been studied in this regard. This drug is useful in Zika virus treatment, with in vivo results indicating regression in neuronal effects often associated with this infection. Several cancer types have also been researched, from breast to leukemia and pancreatic cancer, and rilpivirine has proved to have inhibitory effects in various cell lines with low concentrations, causing cellular death, apoptosis, and cell cycle arrest. The pathways are not yet established, but some works have hypothesized and demonstrated that rilpivirine causes inhibition of Aurora A kinase and has effects on the Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathway and the vascular endothelial growth factors-receptors (VEGFs-VEGFRs) pathway, which are known to be altered in cancer and tumors and can be targeted for cancer treatment. Further testing and clinical trials are needed, but this review demonstrates the potential of rilpivirine's repurposing for cancer treatment.