Long-acting injectable therapy: an emerging paradigm for the treatment of HIV infection

Improvements in Patient-Reported Outcomes After 12 Months of Maintenance Therapy With Cabotegravir + Rilpivirine Long-Acting Compared With Bictegravir/Emtricitabine/Tenofovir Alafenamide in the Phase 3b SOLAR Study

SOLAR (NCT04542070; registered 2020-09-09) is a Phase 3b study that demonstrated the noninferior virological efficacy of switching to cabotegravir + rilpivirine long-acting (CAB + RPV LA) dosed every 2 months vs. continuing daily oral bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) over 12 months. Participants were randomised (2:1) to switch to CAB + RPV LA or to continue BIC/FTC/TAF. Patient-reported endpoints included treatment preference, treatment satisfaction (12-item HIV Treatment Satisfaction Questionnaire status version), acceptability of injections (Perception of Injection questionnaire [acceptability domain]) and three single-item questions exploring psychological challenges related to HIV treatment (fear of disclosure, adherence-related anxiety and reminder of HIV status). Of 670 participants, 447 participants switched to CAB + RPV LA and 223 continued BIC/FTC/TAF. Overall, 18% were female, median age was 37 years and 31% were non-White. At Month 12, CAB + RPV LA significantly improved treatment satisfaction vs. BIC/FTC/TAF (mean [95% confidence interval (CI)] change: + 3.36 [2.59, 4.13] vs. -1.59 [-2.71, -0.47]; p < 0.001). At Month 12, a higher proportion of CAB + RPV LA arm participants reported improvements across the psychological challenges related to HIV treatment questions compared with BIC/FTC/TAF participants. Participants indicating ≥ 1 psychological challenge at baseline experienced a statistically significant and clinically meaningful improvement in treatment satisfaction after 12 months of CAB + RPV LA vs. continuing BIC/FTC/TAF (adjusted difference [95% CI]: 7.96 [5.65, 10.26]; p < 0.001). Most (90%, 382/425) questionnaire respondents preferred CAB + RPV LA vs. BIC/FTC/TAF (5%, 21/425). Switching to CAB + RPV LA was associated with significantly improved treatment satisfaction and relief from the fear of disclosure, anxiety surrounding adherence and reminder of HIV status.

Potential healthcare resource use and associated costs of every 2 month injectable cabotegravir plus rilpivirine long-acting regimen implementation in the Spanish National Healthcare System compared to daily oral HIV treatments

INTRODUCTION

HIV treatment currently consists of daily oral antiretroviral therapy (ART). Cabotegravir + rilpivirine long-acting (CAB + RPV LA) is the first ART available in Spain administered every 2 months through intramuscular injection by a healthcare professional (HCP). The objective of this analysis was to assess potential healthcare resource use (HRU) and cost impact of implementing CAB + RPV LA vs. daily oral ART at National Health System (NHS) hospitals.

METHODS

Online quantitative interviews and cost analysis were performed. Infectious disease specialists (IDS), hospital pharmacists (HP) and nurses were asked about their perception of potential differences in HRU between CAB + RPV LA vs. daily oral ART, among other concepts of interest. Spanish official tariffs were applied as unit costs to the HRU estimates (€2022).

RESULTS

120 responders (n = 40 IDS, n = 40 HP, n = 40 nurses) estimated an average number of annual visits per patient by speciality (IDS, HP, and nurse, respectively) of 3.3 vs. 3.7; 4.4 vs. 6.2; 6.1 vs. 3.9, for CAB + RPV LA vs. daily oral ART, and 3.0 vs. 3.2; 4.8 vs. 5.8; 6.9 vs. 4.9, respectively when adjusting by corresponding specialist responses. Estimation by the total sample led to an annual total cost per patient of €2,076 vs. €2,473, being €2,032 vs. €2,237 after adjusting by corresponding HCP, for CAB + RPV LA vs. daily oral ART.

CONCLUSIONS

These results suggest that the implementation of CAB + RPV LA in NHS hospitals would not incur in increased HRU-related costs compared to current daily oral ARTs, being potentially neutral or even cost-saving.

Acceptability of Long-Acting Injectable Antiretroviral Treatment for HIV Management: Perspectives of Patients and Physicians in Spain

We assessed the prevalence and factors associated with HIV-infected patients' interest in trying long-acting injectable antiretroviral treatment (LAI-ART) along with its expected benefits and concerns, and evaluated physicians' opinions about LAI-ART. This study was set within the multi-center prospective CoRIS cohort, comprising HIV-positive adults, naïve to antiretroviral treatment (ART) at study entry, recruited from 2004 onward in 48 centers in Spain. In June 2022, we conducted a 2-day cross-sectional survey among patients across 34 CoRIS centers and sent an online questionnaire to all physicians prescribing ART in 39 CoRIS centers. Of the 271 patients included, 83.3% [95% confidence interval (CI)]: 78.0 - 87.0%) expressed interest in receiving LAI-ART. This interest was higher among men (adjusted odds ratio: 2.96; 95% CI: 1.4-6.12), those aged <50 years (2.41; 1.23 - 4.73), and individuals inconvenienced by oral ART (5.03; 1.47 - 17.15), daily intake (14.65; 3.44-62.46), carrying HIV pills constantly (7.19; 2.88 - 17.96), and taking multiple medications (3.94; 1.58 - 9.85). Among the 154 physicians surveyed, 45.5% believed LAI-ART would be the preferred option for patients. Although most physicians (92.9%) thought LAI-ART could improve patients' quality of life (QoL), concerns were raised by 37.7% and 44.2% of them regarding injection site pain and visit rescheduling, respectively. Interest in LAI-ART was higher among men, those aged <50 years, and individuals finding their oral ART inconvenient. Physicians believed LAI-ART could improve QoL and overcome treatment challenges, yet concerns were raised about its potential usage difficulties. Although most patients were interested in receiving LAI-ART, only less than half of the physicians considered it their preferred option, likely owing to concerns about missed visits and injection site pain.

LAI-ART Awareness, Willingness, Barriers and Facilitators among Black Sexual Minority Men Living with HIV in the US South

Black sexual minority men (BSMM) continue to bear a disproportionate burden of HIV in the United States, with the highest incidence and prevalence in the southern region of the country. In Texas, BSMM living with HIV (BSMM+) have the lowest rates of viral suppression of all SMM and have lower antiretroviral treatment (ART) adherence than white and Hispanic SMM. Long-acting injectable ART (LAI-ART) can potentially overcome several barriers to daily oral ART adherence (e.g., stigma, forgetfulness, pill fatigue). However, little is known about the knowledge, willingness, barriers, and facilitators regarding LAI-ART among BSMM+. From July 2022 to September 2023, we conducted in-depth, semi-structured interviews with 27 BSMM+ from the Houston and Dallas Metropolitan Areas, Texas. Data were analyzed using a thematic analysis approach. Most men knew about LAI-ART, but their understanding varied based on their existing sources of information. Some men were enthusiastic, some were cautious, and some reported no interest in LAI-ART. Barriers to LAI-ART included a lack of public insurance coverage of LAI-ART; fear of needles and side effects; the frequency of injection visits; the requirement of viral suppression before switching from oral ART to LAI-ART; and satisfaction with oral daily ART. Motivators of LAI-ART uptake included the eliminated burden of daily pills and reduced anxiety about possibly missing doses. BSMM+ may be among those who could most benefit from LAI-ART, though more research is needed to understand which factors influence their willingness and how the barriers to LAI-ART might be addressed, particularly among diverse communities of SMM of color.

Patient Participant Perspectives on Implementation of Long-Acting Cabotegravir and Rilpivirine: Results From the Cabotegravir and Rilpivirine Implementation Study in European Locations (CARISEL) Study

INTRODUCTION

CARISEL is an implementation-effectiveness "hybrid" study examining the perspectives of people living with HIV-1 (patient study participants [PSPs]) on cabotegravir (CAB) plus rilpivirine (RPV) long-acting (LA) dosed every 2 months (Q2M) across 5 European countries.

METHODS

PSPs completed questionnaires on acceptability (Acceptability of Intervention Measure), appropriateness (Intervention Appropriateness Measure), and feasibility (Feasibility of Intervention Measure) at their first (Month [M] 1), third (M4), and seventh (M12) injection visits. Semistructured qualitative interviews were also conducted.

RESULTS

Overall, 437 PSPs were enrolled, of whom 430 received treatment. Median (interquartile range) age was 44 (37-51) years, 25.3% (n = 109/430) were female (sex at birth), and 21.9% (n = 94/430) were persons of color. Across time points, PSPs found CAB + RPV LA highly acceptable, appropriate, and feasible (mean scores ≥4.47/5). Qualitative data supported these observations.

CONCLUSIONS

PSPs found CAB + RPV LA Q2M to be an acceptable, appropriate, and feasible treatment option.

Strategies in the Design and Development of Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs)

AIDS (acquired immunodeficiency syndrome) is a potentially life-threatening infectious disease caused by human immunodeficiency virus (HIV). To date, thousands of people have lost their lives annually due to HIV infection, and it continues to be a big public health issue globally. Since the discovery of the first drug, Zidovudine (AZT), a nucleoside reverse transcriptase inhibitor (NRTI), to date, 30 drugs have been approved by the FDA, primarily targeting reverse transcriptase, integrase, and/or protease enzymes. The majority of these drugs target the catalytic and allosteric sites of the HIV enzyme reverse transcriptase. Compared to the NRTI family of drugs, the diverse chemical class of non-nucleoside reverse transcriptase inhibitors (NNRTIs) has special anti-HIV activity with high specificity and low toxicity. However, current clinical usage of NRTI and NNRTI drugs has limited therapeutic value due to their adverse drug reactions and the emergence of multidrug-resistant (MDR) strains. To overcome drug resistance and efficacy issues, combination therapy is widely prescribed for HIV patients. Combination antiretroviral therapy (cART) includes more than one antiretroviral agent targeting two or more enzymes in the life cycle of the virus. Medicinal chemistry researchers apply different optimization strategies including structure- and fragment-based drug design, prodrug approach, scaffold hopping, molecular/fragment hybridization, bioisosterism, high-throughput screening, covalent-binding, targeting highly hydrophobic channel, targeting dual site, and multi-target-directed ligand to identify and develop novel NNRTIs with high antiviral activity against wild-type (WT) and mutant strains. The formulation experts design various delivery systems with single or combination therapies and long-acting regimens of NNRTIs to improve pharmacokinetic profiles and provide sustained therapeutic effects.

Factors Associated with Preferences for Long-Acting Injectable Antiretroviral Therapy Among Adolescents and Young People Living with HIV in South Africa

Long-acting injectable anti-retroviral therapy (LAART) may overcome barriers to long-term adherence and improve the survival of adolescents and young people living with HIV (AYLHIV). Research on the acceptability of LAART for this age-group is limited. We asked 953 AYLHIV about their preferred (theoretical) ART mode of delivery (pill, injectable, or other) in 2017-2018, before LAART was available or known to AYLHIV in South Africa. One in eight (12%) AYLHIV preferred LAART over single or multiple pill regimens. In multivariate analyses, six factors were associated with LAART preference: medication stock-outs (aOR = 2.56, 95% CI 1.40-4.68, p = 0.002), experiencing side-effects (aOR = 1.84, 95% CI 1.15-2.97, p = 0.012), pill-burden (aOR = 1.88, 95% CI 1.20-2.94, p = 0.006), past-year treatment changes (aOR = 1.63, 95% CI 1.06-2.51, p = 0.025), any HIV stigma (aOR = 2.22, 95% CI 1.39-3.53, p ≤ 0.001) and recent ART initiation (aOR = 2.02, 95% CI 1.09-3.74, p = 0.025). In marginal effects modelling, 66% of adolescents who experienced all factors were likely to prefer LAART, highlighting the potential high acceptability of LAART among adolescents and young people living with HIV struggling to adhere and have good HIV treatment outcomes. Adolescent boys who reported high ART pill burden were more likely to prefer LAART than their female peers in moderation analyses, suggesting that LAART may be particularly important to improve treatment outcomes among male AYLHIV as they become older. Adding LAART to existing treatment options for AYLHIV, particularly higher risk groups, would support AYLHIV to attain and sustain viral suppression-the third 95, and reduce their risk of AIDS-related mortality.

Who's slipping through the cracks? A comprehensive individual, clinical and health system characterization of people with virological failure on first-line HIV treatment in Uganda and South Africa

OBJECTIVES

HIV virological failure remains a major threat to programme success in sub-Saharan Africa. While HIV drug resistance (HIVDR) and inadequate adherence are the main drivers of virological failure, the individual, clinical and health system characteristics that lead to poor outcomes are not well understood. The objective of this paper is to identify those characteristics among people failing first-line antiretroviral therapy (ART).

METHODS

We enrolled a cohort of adults in HIV care experiencing virological failure on first-line ART at five sites and used standard statistical methods to characterize them with a focus on three domains: individual/demographic, clinical, and health system, and compared each by country of enrolment.

RESULTS

Of 840 participants, 51% were women, the median duration on ART was 3.2 years [interquartile range (IQR) 1.1, 6.4 years] and the median CD4 cell count prior to failure was 281 cells/µL (IQR 121, 457 cells/µL). More than half of participants [53%; 95% confidence interval (CI) 49-56%] stated that they had > 90% adherence and 75% (95% CI 72-77%) took their ART on time all or most of the time. Conversely, the vast majority (90%; 95% CI 86-92%) with a completed genotypic drug resistance test had any HIV drug resistance. This population had high health system use, reporting a median of 3 (IQR 2.6) health care visits and a median of 1 (IQR 1.1) hospitalization in the preceding 6 months.

CONCLUSIONS

Patients failing first-line ART in sub-Saharan Africa generally report high rates of adherence to ART, have extremely high rates of HIV drug resistance and utilize significant health care resources. Health systems interventions to promptly detect and manage treatment failure will be a prerequisite to establishing control of the HIV epidemic.

Key population perceptions and opinions about long-acting antiretrovirals for prevention and treatment: a scoping review

PURPOSE OF REVIEW

Key populations are disproportionately affected by human immunodeficiency virus (HIV). Access, retention, and adherence are important barriers for the efficacy of preexposure prophylaxis (PrEP) and HIV treatment among these populations. Long-acting (LA) antiretrovirals hold the promise to solve some of these backdrops. The objective of the current review is to update the perceptions of key populations and PLWH about LA, based on their opinion, acceptability, and willingness to use it.

RECENT FINDINGS

According to the review preferences for LA vary with the population studied. Regarding people living with HIV (PLWH), male having sex with men are interested in having different options, adolescents are interested in LA (strong preference for implants), yet also perceive substantial obstacles to using biomedical prevention; transgender women aimed to nonvisible small implants, with long-lasting effects or LA injections that can be applied in other areas than buttocks, and women who experienced history of medical injections might increase preference for LA (except for history of people who inject drugs [IDU]). Female sex workers and IDU both showed interest in LA-PrEP. Regarding antiretroviral therapy, LA increased treatment satisfaction and acceptance, mainly among those receiving injections every 2 months. LA helped overcome pill fatigue, stigma, and adherence issues.

SUMMARY

Knowing preferences for biomedical interventions will contribute to better understanding and developing effective strategies for these populations.

Week 96 extension results of a Phase 3 study evaluating long-acting cabotegravir with rilpivirine for HIV-1 treatment

BACKGROUND

ATLAS (NCT02951052), a phase 3, multicenter, open-label study, demonstrated that switching to injectable cabotegravir (CAB) with rilpivirine (RPV) long-acting dosed every 4 weeks was noninferior at week (W) 48 to continuing three-drug daily oral current antiretroviral therapy (CAR). Results from the W 96 analysis are presented.

METHODS AND DESIGN

Participants completing W 52 of ATLAS were given the option to withdraw, transition to ATLAS-2M (NCT03299049), or enter an Extension Phase to continue long-acting therapy (Long-acting arm) or switch from CAR to long-acting therapy (Switch arm). Endpoints assessed at W 96 included proportion of participants with plasma HIV-1 RNA less than 50 copies/ml, incidence of confirmed virologic failure (CVF; two consecutive HIV-1 RNA ≥200 copies/ml), safety and tolerability, pharmacokinetics, and patient-reported outcomes.

RESULTS

Most participants completing the Maintenance Phase transitioned to ATLAS-2M (88%, n = 502/572). Overall, 52 participants were included in the W 96 analysis of ATLAS; of these, 100% (n = 23/23) and 97% (n = 28/29) in the Long-acting and Switch arms had plasma HIV-1 RNA less than 50 copies/ml at W 96, respectively. One participant had plasma HIV-1 RNA 50 copies/ml or higher in the Switch arm (173 copies/ml). No participants met the CVF criterion during the Extension Phase. No new safety signals were identified. All Switch arm participants surveyed preferred long-acting therapy to their previous daily oral regimen (100%, n = 27/27).

CONCLUSION

In this subgroup of ATLAS, 98% (n = 51/52) of participants at the Extension Phase W 96 analysis maintained virologic suppression with long-acting therapy. Safety, efficacy, and participant preference results support the therapeutic potential of long-acting CAB+RPV treatment for virologically suppressed people living with HIV-1.

Correlates of Treatment and Disease Burden in People Living with HIV (PLHIV) in Italy

Treatment burden is a multidimensional concept, including several aspects of life of patients affected by chronic conditions. It has been poorly explored in people living with HIV (PLHIV). An online anonymous survey of PLHIV taking antiretroviral therapy (ART) was conducted, in order to investigate the self-reported correlates of disease burden. HIV Treatment and Diseases Burden (TDB) was investigated with a questionnaire containing 31 items in 7 domains. Respondents were stratified in high burden (H-TDB)/low burden (L-TDB) according to overall HIV TDB mean + 1 standard deviation. Factors associated with H-TDB has been evaluated with a logistic regression model. In total, 531 PLHIV completed the questionnaire. 99 PLHIV had a H-TDB (18.6%). PLHIV with H-TDB were younger (p < 0.001), less frequently on current two drug antiretroviral (ARV) regimens (p = 0.01) and more frequently with plasma HIV-RNA >50 copies/mL (p = 0.04). At multivariable regression analysis, younger age (aOR 1.43, 95%CI 1.14–1.80; p = 0.002), not fully treatment satisfaction (aOR 2.19, 95%CI 1.28–3.74; p = 0.004), the need of a more accurate dialogue with treating physician (aOR 2.29, 95%CI 1.21–4.36, p = 0.01) and a self-declared lower overall Health Status (aOR 1.75, 95%CI 1.33–2.32; p = 0.002) were all associated with a H-TDB. One out of five PLHIV showed a high level of treatment and disease burden. Younger age, not fully satisfaction with ART and need of interaction with a tailored health system should be taken into consideration as correlates of treatment and disease burden in a patient-centered approach, to reduce the negative impact that it can produce on the overall perceived health status of the person.

A new paradigm for antiretroviral delivery: long-acting cabotegravir and rilpivirine for the treatment and prevention of HIV

PURPOSE OF REVIEW

Cabotegravir (CAB) and rilpivirine (RPV) is the first long-acting injectable antiretroviral therapy (ART) option approved for virologically suppressed adults with HIV-1. In addition, long-acting CAB is a promising agent for HIV preexposure prophylaxis (PrEP). This review focuses on phase 3 clinical trial results and implementation considerations for these long-acting ART and PrEP strategies.

RECENT FINDINGS

Long-acting CAB and RPV administered every 4 weeks demonstrated noninferiority to oral ART through week 96 in both the ATLAS and FLAIR studies, whereas ATLAS-2M found similar efficacy through 96 weeks when the long-acting injectable ART was administered every 8 weeks instead of every 4 weeks. For prevention, two phase 3 trials were stopped early due to fewer incident HIV infections in participants receiving long-acting CAB every 8 weeks compared with daily oral tenofovir disoproxil fumarate-emtricitabine for PrEP. The long-acting therapies were well tolerated across all clinical trials.

SUMMARY

Clinical trial results support the use of long-acting CAB for HIV PrEP and long-acting CAB and RPV as a switch strategy for adults with HIV-1 who are first virologically suppressed with oral ART. Implementation challenges persist, and data are urgently needed in populations who may benefit most from long-acting therapy, including adolescents, pregnant individuals, and those with barriers to medication adherence.

Population pharmacokinetics of the rilpivirine long-acting formulation after intramuscular dosing in healthy subjects and people living with HIV

OBJECTIVES

To characterize the population pharmacokinetics of the rilpivirine long-acting (LA) formulation after intramuscular administration.

METHODS

Rich and sparse rilpivirine plasma concentration data were obtained from seven clinical studies. In total, 18 261 rilpivirine samples were collected from 986 subjects (131 healthy subjects from Phase I studies and 855 people living with HIV from Phase IIb/III studies). Doses ranged from 300 to 1200 mg, as single-dose or multiple-dose regimens (every 4 or 8 weeks). In Phase III studies, an initiation injection of 900 mg followed by continuation injections of 600 mg every 4 weeks was used. Non-linear mixed-effects modelling was performed using NONMEM® software.

RESULTS

A one-compartment model with linear elimination and two parallel absorption pathways (fast and slow) with sequential zero-first-order processes adequately captured rilpivirine flip-flop pharmacokinetics after intramuscular administration of the LA formulation. The estimated apparent elimination half-life of rilpivirine LA was 200 days. None of the evaluated covariates (age, body weight, BMI, sex, race, health status and needle length) had a clinically relevant impact on rilpivirine pharmacokinetics.

CONCLUSIONS

The population pharmacokinetic model suitably describes the time course and associated variability of rilpivirine plasma concentrations after rilpivirine LA intramuscular administration. The monthly regimen consists of an oral lead-in period (rilpivirine 25 mg tablets once daily for 4 weeks), followed by an initiation injection of 900 mg rilpivirine LA, then 600 mg rilpivirine LA continuation injections monthly. The absence of a clinically relevant effect of covariates on rilpivirine pharmacokinetics suggests that rilpivirine LA dose adjustments for specific subgroups are not warranted.

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

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

Challenges and opportunities in the development of complex generic long-acting injectable drug products

Long-acting injectable (LAI) drug products enable the controlled release of a drug over an extended duration of time to improve the therapeutic effect, safety profile, or administration of an injectable product. The development of generic [505(j)] and differentiated [505(b)(2)] LAI products helps to provide patients and healthcare providers with more treatment options and to reduce overall healthcare costs, including those associated with drug product administration and patient compliance. In this review, we analyze the landscape of LAI products and identify the most common technical challenges that potential generic product entrants face. We focus on five formulation technologies that account for ~90% of approved LAI products, including those eligible for generic product registration over the next five years, to illustrate technology-specific challenges. We then review efforts from the U.S. Food and Drug Administration (FDA) to promote more generic product competition and emphasize the importance of collaboration among government, industry, and academia to advance the knowledge and capabilities of the scientific community. Regulatory bodies, industry, and academia are encouraged to anticipate challenges with emerging innovative LAI technologies and to leverage the experiences built on established technologies to foster generic product development.

Impact of Formulation Parameters on In Vitro Release from Long-Acting Injectable Suspensions

The development of long-acting injectable (LAI) suspension products has increased in recent years. A better understanding of the relationship between the physicochemical properties of these products and their in vitro as well as in vivo performance is expected to further facilitate their development and regulatory review. Using Depo-SubQ Provera 104® as the reference listed drug (RLD), four qualitatively and quantitatively (Q1/Q2) equivalent LAI suspensions with different formulation properties were prepared. Two recrystallization methods (solvent evaporation and antisolvent) were utilized to obtain active pharmaceutical ingredient (API) with different properties and solid-state characterization was performed. In addition, two different sources of the major excipient were used to prepare the Q1/Q2 equivalent suspensions. Physiochemical characterization and in vitro release testing of the prepared Q1/Q2 equivalent suspension formulations and the RLD were conducted. In vitro drug release was dependent not only on the particle size, the morphology, and the crystallinity of the API but also on the residual solvent in the API. The excipient source also affected the drug release rates.

The LAIs Are Coming! Implementation Science Considerations for Long-Acting Injectable Antiretroviral Therapy in the United States: A Scoping Review

Long-acting injectable antiretroviral therapy (LAI-ART) is one of the latest advancements in HIV control with the potential to overcome oral ART barriers to adherence. The objective of this article is to anticipate and examine implementation considerations for LAI-ART using components of the PRISM model, a Practical, Robust Implementation and Sustainability Model for integrating research findings into practice. We conducted a scoping review from January to August 2020 of the growing literature on LAI-ART implementation and other fields using LAI therapies. Key considerations regarding LAI-ART were parsed from the searches and entered into the PRISM implementation science framework. The PRISM framework posed multiple questions for consideration in the development of an optimal implementation strategy for LAI-ART in the United States. These questions revealed the necessity for more data, including acceptability of LAI-ART among many different subgroups of people living with HIV (PLWH), cost effectiveness, patient satisfaction, and patient-reported outcomes, as well as more detailed information related to the external environment for optimal LAI-ART implementation. Ethical considerations of LAI-ART will also need to be considered. The anticipation of, and excitement for, LAI-ART represent the hope for a new direction for HIV treatment that reduces adherence barriers and improves prognoses for PLWH. We have a unique window of opportunity to anticipate implementation considerations for LAI-ART, so this new therapy can be used to its fullest potential. Outstanding questions remain, however, that need to be addressed to help achieve HIV suppression goals in diverse populations.

Time-space constraints to HIV treatment engagement among women who use heroin in Dar es Salaam, Tanzania: A time geography perspective

Timely initiation and sustained adherence to antiretroviral therapy (ART) are essential to improving the health outcomes of people living with HIV and preventing onward HIV transmission. However, women who use heroin often face challenges to initiating and adhering to ART. In this paper we identify spatial, temporal, and social factors that affect HIV treatment engagement among women who use heroin, drawing from a time geography framework. We conducted in-depth interviews with 30 heroin-using women living with HIV in Dar es Salaam, Tanzania between January and March 2019. We found that unstable housing, high mobility, HIV-related stigma, and unpredictable daily paths due to heroin use and involvement in sex work spatially and temporally constrained women who use heroin from incorporating HIV treatment behaviors into daily routines. Some women, however, were able to overcome these time-space constraints to HIV treatment engagement through social support and social role performance. Time geography, including concepts of time-space constraints and daily paths, is a useful framework for identifying barriers to ART engagement. Structural, relational, and individual interventions aimed at eliminating time-space constraints hold the potential to improve HIV treatment engagement among particularly vulnerable and mobile populations.

Reasons People Living with HIV Might Prefer Oral Daily Antiretroviral Therapy, Long-Acting Formulations, or Future HIV Remission Options

A growing body of research is beginning to elucidate reasons people living with HIV (PLWHIV) might prefer oral daily antiretroviral treatment (ART) compared with emerging long-acting ART (LA-ART) or HIV remission strategies under investigation. Our objective is to provide qualitative insights into the reasons why PLWHIV might prefer one of these HIV control therapies over others. From May to August 2018, we implemented a semistructured cross-sectional survey of PLWHIV in the United States to better understand patient preferences around various HIV treatment and remission options. Using free text, respondents were asked to explain why they preferred one HIV control option over the other two. We analyzed responses to the open-ended survey questions on reasons for preferring oral daily ART versus LA-ART versus HIV remission strategies using conventional content analysis. The results showed that PLWHIV preferred oral daily ART because of its familiarity and known safety and efficacy profile, whereas those who preferred LA-ART would value the convenience it offers. Finally, HIV remission strategies would be preferred to avoid taking ART altogether. The qualitative results provide insights into reasons why PLWHIV in the United States might prefer oral daily ART versus novel therapies. More importantly, they provide information to better align HIV virological control strategies with end-user perspectives. To make informed choices around evolving HIV therapeutics, PLWHIV and HIV care providers would benefit from decision tools to better assess options and trade-offs. More research is needed on how best to effectively support PLWHIV and HIV care providers in shared decision-making.

An evaluation of cabotegravir for HIV treatment and prevention

Introduction: Oral pre-exposure prophylaxis (PrEP) and antiretroviral therapy (ART) represent the cornerstones of HIV infection prevention and treatment. However, despite their high efficacy, the need to take daily oral pill(s) negatively impacts long-term patient adherence. In some cases, it can also be associated with drug-drug interactions and adverse gastrointestinal effects, as well as being a constant reminder to individuals of their HIV status. The availability of long-acting non-orally administered antiretroviral drugs could, therefore, be extremely useful. Cabotegravir (CAB) is a second-generation integrase strand transfer inhibitor, characterized by a relatively high genetic barrier and good antiretroviral potency, which is administrable as a long-acting injectable suspension (LAI CAB).Areas covered: The authors present and discuss the efficacy and available safety data of LAI CAB, either when co-administered with rilpivirine (RPV; LAI CAB + RPV) for the treatment of HIV infection, or when used as single agent for PrEP.Expert opinion: Cabotegravir has the potential to play a primary role in the treatment and prevention of HIV infection. The future availability of LAI CAB + RPV and LAI CAB may mark the beginning of an era of LAI ART and PrEP, respectively.

Perceptions of HIV Virologic Control Strategies Among Younger and Older Age Groups of People Living with HIV in the United States: A Cross-Sectional Survey

Two HIV virologic control advances are in various stages of development, including long-acting antiretroviral therapy (ART) formulations and strategies aimed at sustained ART-free HIV control. Perceptions of risks and benefits toward HIV virologic control strategies may be different based on an individual's age due to differing experiences of the impacts of the domestic HIV epidemic, altruistic attitudes toward research participation, and general levels of engagement in health care. We examined preferences of HIV virologic control strategies by age groups. In 2018, we conducted a nationwide, online cross-sectional survey to examine differences in HIV virologic control strategies among a sample of people living with HIV who were <50 and ≥50 years of age. From a total of 281 participants, 3 findings were noteworthy: (1) Participants <50 years of age were more likely to be demotivated by perceived social risks (e.g., stigma, discrimination, HIV disclosure, and fear of transmitting HIV during a treatment interruption), compared with those ≥50 years; (2) participants ≥50 years of age were more motivated by altruistic notions compared with those <50 years; and (3) we noted greater desirability of longer long-acting ART and new HIV cure-related strategies among participants <50 years versus those ≥50 years. Our analysis provides a deeper understanding of differences in perceptions among various age groups regarding desirable future ART characteristics, and motivations and barriers to participating in HIV cure-related strategies. Our findings can help inform community engagement and education, and assist researchers in tailoring study design and recruitment efforts to major age groups.

The dynamics of a simple, risk-structured HIV model

Many diseases, such as HIV, are heterogeneous for risk. In this paper, we study an infectious-disease model for a population with demography, mass-action incidence, an arbitrary number of risk classes, and separable mixing. We complement our general analyses with two specific examples. In the first example, the mean of the components of the transmission coefficients decreases as we add more risk classes. In the second example, the mean stays constant but the variance decreases. For each example, we determine the disease-free equilibrium, the basic reproduction number, and the endemic equilibrium. We also characterize the spectrum of eigenvalues that determine the stability of the endemic equilibrium. For both examples, the basic reproduction number decreases as we add more risk classes. The endemic equilibrium, when present, is asymptotically stable. Our analyses suggest that risk structure must be modeled correctly, since different risk structures, with similar mean properties, can produce different dynamics.

Pathways towards human immunodeficiency virus elimination

Antiretroviral therapy (ART) suppresses human immunodeficiency virus (HIV) infection. Research seeking to transform viral suppression into elimination has generated novel immune, chemical and molecular antiviral agents. However, none, to date, have excised latent integrated proviral DNA or removed infected cells from infected persons. These efforts included, but are not limited to, broadly neutralizing antibodies, "shock" and "kill" latency-reversing agents, innate immune regulators, and sequential long-acting antiretroviral nanoformulated prodrugs and CRISPR-Cas9 gene editing. While, the latter, enabled the complete excision of latent HIV-1 from the host genome success was so far limited. We contend that improvements in antiretroviral delivery, potency, agent specificity, or combinatorial therapies can provide a pathway towards complete HIV elimination.