Lessons for Patient Education Around Long-Acting Injectable PrEP: Findings from a Mixed-Method Study of Phase II Trial Participants

Behind Prep Decisions: Understanding User Patterns and Discontinuation Factors in Real-World

This study aimed to characterize the epidemiological aspects of PrEP use and barriers to accessing this prophylaxis. This cross-sectional study was conducted between January 2021 and April 2022, encompassing 140 PrEP users treated at the Testing and Counseling Center (CTA) in Campo Grande, Mato Grosso do Sul. Data on sociodemographic characteristics and factors associated with PrEP discontinuation were obtained using a standardized questionnaire. Most PrEP users were cisgender men (92.00%), predominantly white (51.00%), over 30 years of age (56.50%), homosexual-oriented (76.50%), and had a minimum of 12 years of education (77.50%). Approximately 60.00% admitted to inconsistent condom use in recent sexual encounters, primarily involving anal intercourse. Approximately 88.00% perceived themselves as at risk of contracting STIs in the upcoming year. Regarding new presentation forms, 54.00% indicated a willingness to use "on-demand PrEP," and 92.00% expressed interest in using "injectable PrEP." After 6 months of follow-up, 43.60% (95.00% CI: 35.50-52.00) discontinued PrEP use, primarily due to changes in sexual behavior (38.30%) and difficulties accessing healthcare services (21.28%). This study underscores the need to involve diverse key populations and highlights the significance of PrEP as an ongoing monitoring strategy for HIV/STI prevention in addition to the importance of incorporating new formulations such as daily oral PrEP into the Brazilian National Health System (SUS).

Provider Factors Likely to Impact Access and Uptake of Long-Acting Injectable Cabotegravir for Transgender Women in the United States: Results of a Qualitative Study

ABSTRACT

Long-acting injectable cabotegravir (CAB-LA) was US Food and Drug Administration-approved in 2021. However, little is known about providers' CAB-LA knowledge, attitudes, challenges, and prescribing preferences for transgender women patients. Understanding this is critical to developing new pre-exposure prophylaxis (PrEP) interventions tailored to transgender women. We conducted 45-min, in-depth Zoom interviews (IDIs) with United States-based health care providers who prescribe PrEP to transgender women. IDIs focused on providers' CAB-LA knowledge/acceptability, willingness to prescribe CAB-LA to transgender women, potential challenges, and solutions to mitigate challenges. Providers ( N = 17) had a mean age of 43 years, and 35.4% ( n = 6) identified as people of color. Most ( n = 12) had basic knowledge of CAB-LA but wanted additional training. All participants found CAB-LA acceptable and were willing to prescribe. Most ( n = 11) anticipated minimal challenges to implementation. Others ( n = 4) reported potential issues, including logistical/scheduling concerns that impede CAB-LA integration and staffing concerns. Many providers expressed support for self-injection ( n = 13) and injections at "drop-in" clinics ( n = 8) to overcome challenges.

Interest in I-PrEP and Willingness to Participate in Clinical Trials Among Men and Transfeminine Persons Who have Sex with Men in Sub-Saharan Africa: Quantitative and Qualitative Findings from HPTN 075

This study explored interest in injectable PrEP (I-PrEP) and willingness to participate in clinical trials testing new biomedical HIV prevention strategies among men and transfeminine persons who have sex with men (MSM & TGP), using data collected in the HIV Prevention Trials Network (HPTN) 075 study, which took place at sites in Kenya, Malawi, and South Africa. Data result from a survey among 267 18-44 years old HIV negative participants, complemented with semi-structured interviews with 80 purposively recruited persons. Correlations coefficients were calculated to identify demographic and psychosocial factors associated with interest in I-PrEP. Qualitative interviews were analyzed using concept-driven and subsequent data-driven coding. Most surveyed participants expressed an interest in I-PrEP. Quantitatively, only being interested in other HIV prevention measures was associated with interest in I-PrEP. Qualitatively, most participants preferred I-PrEP to O-PrEP and remained interested in I-PrEP despite barriers such as the somewhat invasive nature of the procedure and potential side effects of I-PrEP. Interest in I-PrEP was driven by the possibility of avoiding sexual or HIV stigma. Access to healthcare and altruism-such as assisting in the development of new HIV prevention methods-positively impacted willingness to participate in clinical trials. With I-PrEP favored by most participants, it is potentially a critical tool to prevent HIV infection among MSM & TGP in sub-Saharan Africa, with the mitigation of stigma as a major advance. Recruitment of MSM & TGP in biobehavioral clinical trials seems feasible, with altruistic reasons and receiving I-PrEP and free medical care as major motivators.

Towards more tolerable subcutaneous administration: Review of contributing factors for improving combination product design

Subcutaneous (SC) injections can be associated with local pain and discomfort that is subjective and may affect treatment adherence and overall patient experience. With innovations increasingly focused on finding ways to deliver higher doses and volumes (≥2 mL), there is a need to better understand the multiple intertwined factors that influence pain upon SC injection. As a priority for the SC Drug Development & Delivery Consortium, this manuscript provides a comprehensive review of known attributes from published literature that contribute to pain/discomfort upon SC injection from three perspectives: (1) device and delivery factors that cause physical pain, (2) formulation factors that trigger pain responses, and (3) human factors impacting pain perception. Leveraging the Consortium's collective expertise, we provide an assessment of the comparative and interdependent factors likely to impact SC injection pain. In addition, we offer expert insights and future perspectives to fill identified gaps in knowledge to help advance the development of patient-centric and well tolerated high-dose/high-volume SC drug delivery solutions.

Systematic review of the values and preferences regarding the use of injectable pre-exposure prophylaxis to prevent HIV acquisition

INTRODUCTION

Pre-exposure prophylaxis (PrEP) is an important HIV prevention option. Two randomized trials have provided efficacy evidence for long-acting injectable cabotegravir (CAB-LA) as PrEP. In considering CAB-LA as an additional PrEP modality for people at substantial risk of HIV, it is important to understand community response to injectable PrEP. We conducted a systematic review of values, preferences and perceptions of acceptability for injectable PrEP to inform global guidance.

METHODS

We searched nine databases and conference websites for peer-reviewed and grey literature (January 2010-September 2021). There were no restrictions on location. A two-stage review process assessed references against eligibility criteria. Data from included studies were organized by constructs from the Theoretical Framework of Acceptability.

RESULTS

We included 62 unique references. Most studies were observational, cross-sectional and qualitative. Over half of the studies were conducted in North America. Men who have sex with men were the most researched group. Most studies (57/62) examined injectable PrEP, including hypothetical injectables (55/57) or placebo products (2/57). Six studies examined CAB-LA specifically. There was overall interest in and often a preference for injectable PrEP, though there was variation within and across groups and regions. Many stakeholders indicated that injectable PrEP could help address adherence challenges associated with daily or on-demand dosing for oral PrEP and may be a better lifestyle fit for individuals seeking privacy, discretion and infrequent dosing. End-users reported concerns, including fear of needles, injection site pain and body location, logistical challenges and waning or incomplete protection.

DISCUSSION

Despite an overall preference for injectable PrEP, heterogeneity across groups and regions highlights the importance of enabling end-users to choose a PrEP modality that supports effective use. Like other products, preference for injectable PrEP may change over time and end-users may switch between prevention options. There will be a greater understanding of enacted preference as more end-users are offered anti-retroviral (ARV)-containing injectables. Future research should focus on equitable implementation, including real-time decision-making and how trained healthcare providers can support choice.

CONCLUSIONS

Given overall acceptability, injectable PrEP should be included as part of a menu of prevention options, allowing end-users to select the modality that suits their preferences, needs and lifestyle.

Optimizing the pipeline of multipurpose prevention technologies: opportunities across women's reproductive lifespans

HIV/AIDS and maternal mortality are the two leading causes of death among women of reproductive age in sub-Saharan Africa. A growing body of research investigates opportunities for multipurpose prevention technologies (MPTs) that prevent unintended pregnancy, HIV, and/or other sexually transmitted infections (STIs) with a single product. More than two dozen MPTs are currently in development, most of them combining contraception with HIV pre-exposure prophylaxis, with or without protection from other STIs. If successful, such MPTs could offer women benefits at multiple levels: greater motivation for effective use; lower product administration burden; accelerated integration of HIV, STI, and reproductive health services; and opportunities to circumvent stigma by using contraception as a "fig leaf" for HIV and/or STI prevention. However, even if women find respite from product burden, lack of motivation, and/or stigma in contraceptive-containing MPTs, their use of MPTs will be interrupted, often multiple times, over the reproductive lifecourse due to desire for pregnancy, pregnancy and breastfeeding, menopause, and changes in risk. Interruptions to the benefits of MPTs could be avoided by combining HIV/STI prevention with other life-stage-appropriate reproductive health products. New product concepts could include combining prenatal supplements with HIV and STI prevention, emergency contraception with HIV post-exposure prophylaxis, or hormone replacement therapies for menopause with HIV and STI prevention. Research is needed to optimize the MPT pipeline based on the populations underserved by available options and the capacity of resource-constrained health systems to deliver novel preventative healthcare 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.

Practices of patient engagement in drug development: a systematic scoping review

BACKGROUND

During the past decade, patient engagement (PE) has attracted significant attention in the field of drug development. Readiness to accept the central importance of patients' knowledge and contributions has become evident. This study aimed to synthesize evidence on the current state of PE in drug development: what is actually being done and how.

METHODS

A systematic scoping review was conducted based on a PRISMA-informed protocol. Search was performed in PubMed, EMBASE and Web of Science, covering the period between 2011 and 2021. For analysis of extracted data, we developed a framework for analyzing PE in Drug Development. The Framework distinguishes a number of different PE types that take place at different stages of drug development and are characterized by the different degrees of power patients have in the process. It allowed us to assess depth and intensity of PE initiatives included in this review.

RESULTS

Most included PE initiatives took place at the stage of designing studies (40 in total). At this stage drug development goals are already set, but the mode of reaching them has not yet been fully determined. PE initiatives on the finetuning details stage followed (16 in total). The finetuning details stage covers the last parts of the drug development trajectory, when only relatively minor issues are still open for patients' contributions. The least numerous were PE initiatives on the stage of setting up R&D program (13 in total). This stage refers to the early steps in drug development where PE has the potential to make the most impact on shaping the subsequent process. In terms of intensity of engagement, most PE initiatives included in this review align with consultation and involvement types, 26 and 30 initiatives, respectively. Partnership was less frequent in the published accounts of PE (13 initiatives).

CONCLUSIONS

This review delineated a contemporary landscape of PE in drug development. Although attention to PE in drug development is relatively recent, a wide range of PE practices has already been initiated. The results indicate the necessity of distinguishing between different types of PE in order to understand consequences of choices regarding depth and intensity of PE.

The systematic development of attributes and levels for a discrete choice experiment of HIV patient preferences for long-acting antiretroviral therapies in the United States

INTRODUCTION

Patient preferences for long-acting antiretroviral therapies (LA-ART) should inform development of regimens with optimal adherence and acceptability. We describe a systematic process used to identify attributes and levels for a discrete choice experiment (DCE) designed to elicit preferences for potential LA-ART options in the US.

METHODS

Our approach was conducted in four stages: data collection, data reduction, removing inappropriate attributes, and optimizing wording. We started with 8 attributes defining potential LA-ART products based on existing literature and knowledge of products in development. We conducted 12 key informant interviews with experts in HIV treatment. The list of attributes, the set of plausible levels for each attribute, and restrictions on combinations of attribute levels were updated iteratively.

RESULTS

Despite uncertainty about which products will become available, key informant discussions converged on 4 delivery modes (infusions and patches were not considered immediately feasible) and 6 additional attributes. Treatment effectiveness and frequency of clinical monitoring were dropped. Oral lead-in therapy was split into two attributes: pre-treatment time undetectable and pre-treatment negative reaction testing. We omitted product-specific systemic and local side effects. In addition to mode, the final set of attributes included: frequency of dosing; location of treatment; pain; pre-treatment time undetectable; pre-treatment negative reaction testing; and late-dose leeway.

CONCLUSIONS

A systematic process successfully captured elements that are both feasible and relevant to evaluating the acceptability of potential LA-ART alternatives to patients.

Transgender Women's Barriers, Facilitators, and Preferences on Tailored Injection Delivery Strategies to Administer Long-Acting Injectable Cabotegravir (CAB-LA) for HIV Pre-exposure Prophylaxis (PrEP)

Long-acting injectable cabotegravir (CAB-LA) is in advanced stages of clinical trials. Under the standard protocol, CAB-LA is injected into the gluteal muscle by a healthcare provider every eight weeks. To explore transgender women’s barriers and facilitators to tailored delivery strategies—including self-injection and injection in “drop-in” centers—we completed in-depth interviews with N = 15 transgender women in New York City. Participants endorsed the alternative delivery methods and the corresponding features we proposed, and expressed likes and dislikes about each. These fell into the following categories: competence (e.g., the person delivering CAB-LA must have skills to do so), convenience (e.g., CAB-LA must be easy to obtain), and privacy or fear of judgement (e.g., participants did not want to feel judged for using CAB-LA by providers or other service consumers). Findings suggest the need to offer CAB-LA to transgender women through multiple delivery protocols.

A Scoping Review Investigating Relationships between Depression, Anxiety, and the PrEP Care Continuum in the United States

Men who have sex with men and transgender women in the United States are at increased risk for HIV and may benefit from pre-exposure prophylaxis (PrEP), a once-a-day pill to prevent HIV. Due to stigma and discrimination, sexual and gender minority (SGM) populations are also at risk for depression and anxiety. This scoping review sought to identify literature addressing relationships between the PrEP care continuum, depression, and anxiety among SGM individuals and others at high risk for HIV. We conducted a systematic review of four databases (i.e., PubMed, PsycInfo, Web of Science, Google Scholar) and identified 692 unique articles that were screened for inclusion criteria, with 51 articles meeting the final inclusion criteria. Data were extracted for key study criteria (e.g., geographic location, participant demographics, study design, main findings). Results suggest that while depression and anxiety are not associated with PrEP awareness or willingness to use, they can be barriers to seeking care and to PrEP adherence. However, empirical studies show that taking PrEP is associated with reductions in anxiety. Findings suggest the need to implement mental health screenings in PrEP clinical care. In addition, addressing systemic and structural issues that contribute to mental health disorders, as well as PrEP-related barriers, is critical.

Formulary Drug Review: Cabotegravir

Each month, subscribers to The Formulary Monograph Service receive 5 to 6 well-documented monographs on drugs that are newly released or are in late phase 3 trials. The monographs are targeted to Pharmacy and Therapeutics Committees. Subscribers also receive monthly 1-page summary monographs on agents that are useful for agendas and pharmacy/nursing in-services. A comprehensive target drug utilization evaluation/medication use evaluation (DUE/MUE) is also provided each month. With a subscription, the monographs are available online to subscribers. Monographs can be customized to meet the needs of a facility. Through the cooperation of The Formulary, Hospital Pharmacy publishes selected reviews in this column. For more information about The Formulary Monograph Service, contact Wolters Kluwer customer service at 866-397-3433.

Statistical approaches to accelerate the development of long-acting antiretrovirals for HIV pre-exposure prophylaxis

PURPOSE OF REVIEW

This review considers statistical issues in the design and analysis of the studies used to develop long-acting formulations of antiretrovirals for pre-exposure prophylaxis (PrEP).

RECENT FINDING

An abundant pipeline of products is maturing. Accelerating their evaluation as clinical products requires abandonment of noninferiority standards. Randomized trials should be based on the comparison of principled but innovative estimates of background HIV risk and enrich enrollment for those who do not desire current PrEP products. At every stage of testing, innovative analyses can be applied to help inform and accelerate later studies.

SUMMARY

The development of new long-acting PrEP regimens can be accelerated by innovations in design, ingenuity in synthesizing data sources, and application of causal inference methods.

The only way is up: priorities for implementing long-acting antiretrovirals for HIV prevention and treatment

Purpose of review

Long-acting HIV treatment and prevention (LAHTP) can address some of the achievement gaps of daily oral therapy to bring us closer to achieving Joint United Nations Programme on HIV/AIDS Fast-track goals. Implementing these new technologies presents individual-level, population-level, and health systems-level opportunities and challenges.

Recent findings

To optimize LAHTP implementation and impact, decision-makers should define and gather relevant data to inform their investment case within the existing health systems context. Programmatic observations from scale-up of antiretroviral therapy, oral preexposure prophylaxis, voluntary medical male circumcision, and family planning offer lessons as planning begins for implementation of LAHTP. Additional data intelligence should be derived from formative studies, pragmatic clinical trials, epidemiologic and economic modeling of LAHTP. Key implementation issues that need to be addressed include optimal communication strategies for demand creation; target setting; logistics and supply chain of commodities needed for LAHTP delivery; human resource planning; defining and operationalizing monitoring and evaluating metrics; integration into health systems.

Summary

Successful LAHTP implementation can bolster treatment and prevention coverage levels if implementation issues outlined above are proactively addressed in parallel with research and development so that health systems can more rapidly integrate new technologies as they gain regulatory approval.

Acceptability of Long-Acting Injectable Cabotegravir (CAB LA) in HIV-Uninfected Individuals: HPTN 077

Long-acting injectable PrEP could offer an alternative to daily oral PrEP, improve adherence and protection, if found acceptable, safe and effective. HPTN 077 evaluated injectable cabotegravir safety, tolerability and pharmacokinetics among HIV-uninfected males and females in sequentially-enrolled cohorts of two dosing strategies. We compared acceptability of product attributes, prevention preferences and future interest in injectable PrEP (FIIP) by region, sex-at-birth, arm and cohort and used multivariable analysis to identify FIIP determinants. Baseline injectable PrEP preferences were higher in non-U.S. sites and increased in both regions over time. In multivariable models, FIIP was most strongly associated with acceptability of product attributes, was higher in non-U.S. sites and more altruistic participants. Treatment arm and report of pain were not associated with FIIP. Injectable acceptability was highest in non-U.S. sites. Preferences for injectable versus other PrEP methods were higher among U.S. males than females, but higher among males and females in non-U.S. settings.

Behavioral and social science research to support development of educational materials for clinical trials of broadly neutralizing antibodies for HIV treatment and prevention

BACKGROUND/AIMS

Early integration of behavioral and social sciences research into clinical trials can improve trial conduct and facilitate future implementation of biomedical interventions. We sought to examine participants' experiences in clinical trials with broadly neutralizing antibodies and describe the development of educational materials for use in future broadly neutralizing antibody research.

METHODS

We conducted semi-structured interviews with trial participants in phase 1 trials evaluating safety and efficacy of broadly neutralizing antibodies for HIV prevention and treatment and key informants (i.e. trial staff involved in broadly neutralizing antibody research). Semi-structured interviews were transcribed and analyzed thematically. Based on findings from the interviews, we developed educational materials addressing concerns and misconceptions identified among trial participants with input from community and research stakeholders. Educational materials were used in subsequent clinical trials with broadly neutralizing antibodies. We evaluated trial staff's experiences with newly developed educational materials in follow-up key informant interviews.

RESULTS

Although most participants were concerned about long-term harms related to the investigational product upon enrollment, absence of severe side effects in the trial led to an underestimation of risks related to the study during trial participation. Participants showed a poor understanding of what broadly neutralizing antibodies are and the differences between broadly neutralizing antibodies and other HIV prevention and treatment products, such as antiretrovirals. Many trial participants overestimated the possible public health impact of the broadly neutralizing antibody trials in which they were enrolled, associating broadly neutralizing antibody research with the development of vaccine or cure for HIV in the near future. Based on these concerns and misconceptions among trial participants, we developed a frequently asked questions document and adapted an existing educational video about broadly neutralizing antibodies. In follow-up interviews, key informants reported that materials helped address trial participants' concerns and questions related to the trial. Key informants reported using the educational materials not only during informed consent but also throughout trial participation, which contributed to making informed consent an "ongoing" process.

CONCLUSION

Integration of behavioral research into clinical trials with broadly neutralizing antibodies is key to identify and address key concerns among trial participants. Behavioral and social sciences research promotes communication between trial participants and biomedical researchers, facilitates engagement of participants and trial staff, and strengthens trial conduct. Development of educational materials collaboratively by behavioral and clinical scientists, trial staff, and community stakeholders is feasible and may help to address trial participants' concerns and misconceptions. Future research should evaluate the impact of educational materials in recruitment and retention of trial participants.

"Talking About it Publicly Made Me Feel Both Curious and Embarrassed": Acceptability, Feasibility, and Appropriateness of a Stigma-Mitigation Training to Increase Health Worker Comfort Discussing Anal Sexuality in HIV Services

Health workers report challenges to broaching sexual behavior with gay and bisexual men (MSM). We conducted a stigma-mitigation training to increase provider-initiated conversation about anal sexuality among Chinese health workers. The two-day workshop, titled Smarter Sex is the New Safer Sex: Anal Pleasure and Health, coupled information about anal physiology and sexual response with gradual exposure to trainees' emotional and cognitive responses. We analyzed surveys and one-time interviews. Acceptability (satisfaction with training activities and recommended practices), feasibility (compatibility with participants' current practices), and appropriateness (perceived fit with participants' work mission and goals) were high, reaching 84-95% of the scale range, though with variable ratings for trainee comfort during participation. Qualitative data confirm health workers' motivation to discuss anal sexuality and the value of learning about anal physiology and sexual response, but revealed continued uncertainty about how to broach and navigate discussion with clients. Refinement of the training to align with health worker recommendations and to augment communication options and skills is warranted, as is involvement of MSM clientele themselves.

Perspectives of injectable long acting antiretroviral therapies for HIV treatment or prevention: understanding potential users' ambivalences

Recent clinical trial data showed that injectable long-acting antiretroviral treatment (LA-ART) every four or eight weeks could become an alternative option for HIV treatment or prevention. The purpose of our study was to explore perceptions and potential users' points of views of this new mode of administration through individuals' therapeutic itinerary and their singular history with ART. Between 2018 and 2019, a qualitative study was conducted in two University Hospitals in Paris, France. In-depth interviews were conducted with 15 virologically controlled People Living with HIV (PLWH) and 13 men on pre-exposure prophylaxis (PrEP) for at least six months. Interviews, focused on the daily experience with ART, were recorded, transcribed, and analyzed using thematic content analysis. Collected discourses were organized around three emergent concerns: social, material and experimental. Each of these concerns was perceived as ambivalent, balanced by skepticism and hope. It revealed the complexity of each individual's relationship to their HIV treatment or PrEP, leading to balance the injectable LA-ART popularity reported within clinical trials. This new mode of administration may be a suitable alternative for some PLWH and PrEP users, a "simplification" compared to the oral route. It opens a window for "customizable" ART-treatment according to individuals' lives.

Long-acting injectable cabotegravir for the prevention of HIV infection

PURPOSE OF REVIEW

This review highlights the development of long-acting injectable cabotegravir (CAB LA) for HIV preexposure prophylaxis (PrEP), with a focus on phase 2 studies and later development.

RECENT FINDINGS

Early studies of CAB LA for HIV prevention offered promising pharmacokinetic data and paved the way for phase 2 studies, which have now been completed. On the basis of phase 2 data, dosing of CAB LA at 8-week intervals consistently delivers target trough concentrations in both men and women. Recent studies have shown no required dose adjustments for hepatic or renal disease and minimal drug--drug interactions. Additionally, injectable PrEP is desired by potential PrEP candidates. Still, gaps in knowledge remain with respect to implementation and delivery, the clinical significance of the pharmacologic tail, and dosing in key populations. Phase 3 trials are underway that are anticipated to inform some of these questions and provide efficacy and safety data to support regulatory submissions for CAB LA as a potential PrEP agent.

SUMMARY

Recent studies have defined an appropriate CAB LA dosing interval and offered insight into its safety profile. Phase 3 studies will provide much-anticipated efficacy data. If efficacious, CAB LA may provide a desirable PrEP option for those who face challenges to daily pill adherence. A more complete understanding of how to best integrate LA PrEP into service delivery models will be critical for success.

Expanding Knowledge About Implementation of Pre-exposure Prophylaxis (PrEP): A Methodological Review

Methodological limitations in PrEP implementation studies may explain why PrEP implementation is lagging. This methodological review provides a description and critique of the methods used to identify barriers to PrEP implementation in the United States (2007-18). For each selected article, we provide: (1) research questions; (2) measures; (3) design; (4) sample (size and type); and (5) theoretical orientation. Among 79 articles which identified knowledge, attitudes, and behavioral and social/structural barriers to PrEP implementation, 51 (65%) were quantitative; 25 (32%) qualitative; and 3 (4%) were mixed-methods; overall, just one-half described a conceptual approach. About two-thirds of articles were conducted with patients and one-third with healthcare providers. Our review reveals a paucity of longitudinal, mixed-methods, and ethnographic/observational research and guiding theoretical frameworks; thus, the applicability of results are limited. We recommend that interventions aimed at PrEP implementation address barriers situated at multiple ecological domains, and thus improve PrEP access, uptake, and adherence.

Mosaic effectiveness: measuring the impact of novel PrEP methods

Various ongoing trials seek to evaluate long-acting pre-exposure prophylaxis (PrEP) agents by showing that they are non-inferior to daily oral tenofovir disoproxil fumarate and emtricitabine. Trials comparing oral PrEP to new methods examine effectiveness in a setting where only one or the other is provided; however, a new product will probably be delivered in a context where oral PrEP is also available. The effectiveness of a new PrEP product is best measured by its potential effect in a context that also includes oral tenofovir disoproxil fumarate and emtricitabine as an option. We offer an alternative standard for long-acting products-a measure of the effectiveness of the new product in addition to oral tenofovir disoproxil fumarate and emtricitabine as compared with oral PrEP alone. We term this measure mosaic effectiveness. We illustrate scenarios where a novel product can fail to show non-inferiority but show substantial mosaic effectiveness, thus implying the public health value of the novel product even if it is less effective than oral PrEP. Regulatory standards should consider mosaic effectiveness, not just comparative effectiveness. We assert that measurements that combine rigor with public health relevance can accelerate progress against the HIV epidemic.

Current and Future PrEP Medications and Modalities: On-demand, Injectables, and Topicals

PURPOSE OF REVIEW

Pre-exposure prophylaxis (PrEP) is a potent HIV prevention strategy, but uptake of daily oral PrEP remains low. This review covers PrEP agents currently available and agents and modalities under investigation.

RECENT FINDINGS

Injectable ARV preparations have high acceptability among users but are likely to require adherence to 8-week interval injections. Topical microbicide gels and vaginal rings have underperformed by intention-to-treat analyses in efficacy studies, at least in large part due to challenges with adherence and/or sustained use. However, daily oral TDF-FTC also underperformed in randomized, placebo-controlled trials compared to expectations and subsequent real-world pragmatic use. On-demand (2-1-1 dosing strategy for MSM) and injectable PrEP appear to be acceptable among participants in clinical trials. These modalities are particularly compelling alternatives for individuals who either do not want to take a daily medication (both on-demand and injectable) and/or want to take PrEP without a long commitment (on-demand). Emerging modalities such as vaginal films, microneedles, and subdermal implants have numerous advantages but are still in early stages of development.

Advancing Novel PrEP Products - Alternatives to Non-Inferiority

With the scale-up of HIV pre-exposure prophylaxis (PrEP) with tenofovir (TDF) with or without emtricitabine (FTC), we have entered an era of highly effective HIV prevention with a growing pipeline of potential products to be studied. These studies are likely to be randomized trials with an oral TDF/FTC control arm. These studies require comparison of incident infections and can be time and resource intensive. Conventional approaches for design and analysis active controlled trial can lead to very large sample sizes. We demonstrate the important of assumptions about background infections for interpreting trial results and suggest alternative criteria for demonstrating the efficacy and effectiveness of potential PrEP agents.

Why I Quit Pre-Exposure Prophylaxis (PrEP)? A Mixed-Method Study Exploring Reasons for PrEP Discontinuation and Potential Re-initiation Among Gay and Bisexual Men

Literature concerning pre-exposure prophylaxis (PrEP) among gay and bisexual identifying men (GBM) has explored facilitators and barriers to uptake and adherence. Far less reported are the reasons why GBM discontinue PrEP use. A national sample of 1071 GBM completed surveys about PrEP use and discontinuation. Participants who were still taking PrEP the 24-month follow up were compared to those that had stopped. Eighteen percent (n = 31) of GBM who reported ever using PrEP discontinued use. Younger (AOR = 0.96; 95% CI 0.92-1.00), and unemployed (AOR = 4.58; 95% CI 1.43-14.70) GBM were more likely to discontinue PrEP than their counterparts. Those that discontinued provided details on why via a free response question. The most common reasons for discontinuation were lower perceived HIV risk (50%) and cost/insurance (30%). Reasons for potential re-initiation included higher-risk sexual activities and changes to structural related barriers. More research is needed to inform interventions on how GBM can continue taking PrEP during changes to employment that effect insurance coverage and cost.

"Free Testing and PrEP without Outing Myself to Parents:" Motivation to participate in oral and injectable PrEP clinical trials among adolescent men who have sex with men

BACKGROUND

Adolescent men who have sex with men (AMSM) account for disproportionately high numbers of new HIV diagnoses. Non-adherence to daily use limiting the effectiveness of oral PrEP (Truvada) has led to current trials with adult MSM testing Cabotegravir, a long-term injectable medication. Once comparative studies with young adult MSM have established relative safety and efficacy of these medications, there will be a need for such comparative trials involving adolescents. Trends in state laws and IRB protocol review indicate that many of these studies will permit youth to provide independent consent for participation. Understanding the motivations of AMSM to participate in HIV biomedical prevention studies is important to ensure their agreement is voluntary without misunderstanding and undue influence. This study examined AMSM attitudes toward participation in oral/injectable PrEP RCTs to inform protections of youth's rights and welfare in future studies.

METHODS

We administered to 198 ethnically diverse U.S. AMSM, 14-17 years, a web-based survey including demographic and sexual health questions, description of a year-long oral versus injectable PrEP RCT and 26 Likert-type and one open-ended item assessing motivations for and against participation including: perceived benefits and risks of PrEP; free HIV/STI testing and counseling; confidentiality concerns; random assignment; and benefit to others.

RESULTS

Sixty-two percent indicated they were likely to participate in the study. The majority endorsed daily HIV protection, free HIV/STI testing, sexual health counseling, not having to rely on partner's condom use, and altruism as reasons to participate. Reasons against participation included medication side effects, concern taking the pill daily and clinic visits would reveal their sexual orientation and behaviors to parents. Over half erroneously assumed they would be assigned to the condition best for them and 39% indicated free access to services would lead them to participate even if they did not want to. Multiple regression indicated these factors accounted for 55% of the variance in participation choice. Nether age or ethnicity yielded significance.

CONCLUSIONS

Results suggest future biomedical HIV prevention research will need to develop procedures to address AMSM's confidentiality concerns, enhance youth's understanding of random assignment, the continued importance of medication adherence and partner condom use during trial participation, and availability of alternative sexual health services to avoid the potentially undue influence of access to free sexual health services.

To switch or not to switch: Intentions to switch to injectable PrEP among gay and bisexual men with at least twelve months oral PrEP experience

BACKGROUND

Phase III trials of long-acting injectable (LAI) PrEP, currently underway, have great potential for expanding the menu of HIV prevention options. Imagining a future in which multiple PrEP modalities are available to potential users of biomedical HIV prevention, we investigated which factors might help direct a patient-physician shared-decision making process to optimize the choice of biomedical HIV prevention method.

METHODS

Participants (n = 105; ages 19-63; 46.7% men of color) were former participants in a PrEP demonstration project and had taken daily oral PrEP for ≥ 12 months. Participants were given information about LAI PrEP and asked whether they would be interested in switching from oral to LAI PrEP. Participants were also asked about specific pros/cons of LAI PrEP, PrEP attitudes and experiences, and personality factors.

RESULTS

Two-thirds (66.7%) of current oral PrEP users would switch to LAI PrEP. Intention to switch was associated with product-level and psychosocial factors. Attitudes towards logistical factors (i.e. getting to regular clinic visits for recurring shots) featured more prominently than factors related to the physical experience of PrEP modality (i.e., concerns about injection pain) as motivators for switching. In a multivariate regression model, psychosocial factors including the emotional burden of daily pill taking, deriving a sense of responsibility from PrEP use, and self-identifying as an early adopter, were the strongest predictors of switching.

CONCLUSIONS

These data underscore the importance of attending not only to product-level factors, but also to the logistical and psychological experience of prevention methods for users. Findings have significant implications for the development of patient education materials and patient-provider shared decision aids.