Long-acting cabotegravir and rilpivirine dosed every 2 months in adults with HIV-1 infection (ATLAS-2M), 96-week results: a randomised, multicentre, open-label, phase 3b, non-inferiority study

Multicentre service evaluation of injectable cabotegravir and rilpivirine delivery and outcomes across 12 UK clinics (SHARE LAI-net)

INTRODUCTION

Long-acting injectable cabotegravir + rilpivirine (CAB + RPV LAI) was approved for use in virally suppressed adults in the England and Wales national health service in November 2021. We describe a service evaluation of delivery processes and outcomes in 12 clinics.

METHODS

Centres populated a database using information from local policies and clinical records. Services were asked to describe approval processes, clinic pathways, and adherence to national guidelines. Additional data were collected on reasons for regimen choice, treatment discontinuations, and management of viraemia.

RESULTS

In total, 518 adults from 12 clinics were approved for CAB + RPV LAI between February 2022 and December 2023. Of the 518 people approved for CAB + RPV LAI, 423 received at least one injection. Median duration on CAB + RPV was 7.5 months (interquartile range 3.7-11.3). In total, 97% of injections were administered within the ±7-day window. Virological failure occurred in 0.7%, and 6% discontinued CAB + RPV.

CONCLUSION

In this large UK-based cohort, robust approval processes and clinic protocols facilitated on-time injections and low rates of both discontinuation and virological failure.

Clinical considerations when switching antiretroviral therapy

INTRODUCTION

Antiretroviral therapy (ART) can be personalized through simple formulations with high resistance barriers, favorable safety profiles, and novel administration routes. Switching treatments has become a key clinical strategy for addressing drug toxicity and interactions and enhancing adherence and convenience. This strategy aims to improve the quality of life and long-term efficacy, even in challenging cases like people living with HIV (PLWH) with multiple comorbidities, prior virological failure, and drug resistance.

AREAS COVERED

The authors reviewed clinical trials and cohort studies providing evidence of benefits and risks of current antiretroviral (ARV) drugs as switching options for PLWH in various scenarios. The literature search included clinical trials, meta-analyses, observational studies, and review articles in English published after 2000, and current HIV treatment guidelines in English and Spanish as of February 2024.

EXPERT OPINION

New ARV drugs offer advantages in efficacy and safety over previous options but may have also adverse effects. Second-generation integrase inhibitors and tenofovir alafenamide show benefits as switching options in various scenarios, though more research is needed on potential weight gain and metabolic issues. Injectable long-acting ART is promising for switching strategies, but finding the optimal combination of new drugs remains challenging.

Injectable antiretroviral therapy: best practice guide for nurses providing care to people living with HIV

Oral antiretroviral therapy (ART) is extremely effective, allowing people living with HIV to have a normal life expectancy. Most treatments consist of oral tablets that must be taken at the same time every day for the rest of an individual's life. For a variety of reasons, some people cannot adhere to a daily regimen, resulting in a deterioration in their health. The introduction in 2021 of long-acting injectable ART has provided an alternative option for those who would prefer not to take oral therapy. This article provides an overview of the practicalities and challenges of setting up nurse clinics to administer these injections. It also highlights how this type of treatment has improved the quality of life for people receiving them. HIV nurse specialists are leading the way in delivering this innovative new treatment, and the article concludes by discussing which patients may benefit from injectables in the future. This guide is aimed at nurses who work within the HIV field or are supporting this treatment in other settings, for example in outpatient parenteral antimicrobial therapy (OPAT) services.

Switch to long-acting cabotegravir and rilpivirine in virologically suppressed adults with HIV in Africa (CARES): week 48 results from a randomised, multicentre, open-label, non-inferiority trial

BACKGROUND

Long-acting injectable cabotegravir and rilpivirine is licensed for individualised treatment of HIV-1 infection in resource-rich settings. Additional evidence is required to support use in African treatment programmes where demographic factors, viral subtypes, previous treatment, and delivery and monitoring approaches differ. The aim of this study was to determine whether switching to long-acting therapy with injections every 8 weeks is non-inferior to daily oral therapy in Africa.

METHODS

CARES is a randomised, open-label, non-inferiority trial being conducted at eight sites in Uganda, Kenya, and South Africa. Participants with HIV viral load below 50 copies per mL on oral antiretroviral therapy and no history of virological failure were randomly assigned (1:1; web-based, permuted blocks) to receive cabotegravir (600 mg) and rilpivirine (900 mg) by intramuscular injection every 8 weeks, or to continue oral therapy. Viral load was monitored every 24 weeks. The primary outcome was week 48 viral load below 50 copies per mL, assessed with the Food and Drug Administration snapshot algorithm (non-inferiority margin 10 percentage points) in the intention-to-treat exposed population. This trial is registered with the Pan African Clinical Trials Registry (202104874490818) and is ongoing up to 96 weeks.

FINDINGS

Between Sept 1, 2021, and Aug 31, 2022, we enrolled 512 participants (295 [58%] female; 380 [74%] previous non-nucleoside reverse transcriptase inhibitor exposure). Week 48 viral load was below 50 copies per mL in 246 (96%) of 255 participants in the long-acting therapy group and 250 (97%) of 257 in the oral therapy group (difference -0·8 percentage points; 95% CI -3·7 to 2·3), demonstrating non-inferiority (confirmed in per-protocol analysis). Two participants had virological failure in the long-acting therapy group, both with drug resistance; none had virological failure in the oral therapy group. Adverse events of grade 3 or greater severity occurred in 24 (9%) participants on long-acting therapy and ten (4%) on oral therapy; one participant discontinued long-acting therapy (for injection-site reaction).

INTERPRETATION

Long-acting therapy had non-inferior efficacy compared with oral therapy, with a good safety profile, and can be considered for African treatment programmes.

FUNDING

Janssen.

Feasibility of Implementing a Low-Barrier Long-Acting Injectable Antiretroviral Program for HIV Treatment and Prevention for People Experiencing Homelessness

BACKGROUND

Long-acting (LA) antiretrovirals may provide meaningful benefit to people who use drugs and people experiencing homelessness (PEH) who face disproportionate structural and psychosocial barriers in adhering to daily oral HIV antiretroviral therapy or pre-exposure prophylaxis (PrEP), but their use in these populations has not been studied.

SETTING

The Maria X. Martinez Health Resource Center is a low-barrier (eg, no appointment) community-based clinic serving San Francisco PEH.

METHODS

A multidisciplinary care model with robust monitoring and outreach support was developed to provide LA antiretroviral therapy (ART) and LA-PrEP to eligible patients experiencing difficulties adhering to oral antiretrovirals. Feasibility was assessed by evaluating the rates of HIV viremia and on-time injections among patients receiving LA antiretrovirals over the first 24 months of program implementation.

RESULTS

Between November 2021 and November 2023, 33 patients initiated LA-ART or LA-PrEP (median age, 37 years; 27% transgender/nonbinary; 73% non-White; 27% street homeless; 52% sheltered homeless; 30% with opioid use disorder; 82% with methamphetamine use disorder). Among 18 patients with HIV, 14 initiated LA-ART injections with detectable viremia (median CD4 count, 340 cells/mm 3 ; mean log 10 viral load, 3.53; SD, 1.62), 8 had never previously been virally suppressed, and all but 1 achieved or maintained virologic suppression (mean, 9.67 months; SD, 8.30). Among 15 LA-PrEP patients, all remained HIV negative (mean, 4.73 months; SD, 2.89). Of 224 total injections administered, 8% were delayed >7 days.

DISCUSSION

The implementation of LA antiretrovirals is feasible in low-barrier, highly supportive clinical settings serving vulnerable PEH. Expansion of such programs will be critical in ending the HIV epidemic.

Preferences and feasibility of long-acting technologies for treatment of hepatitis C virus in low- and middle-income countries: A survey of providers and policymakers

Long-acting technologies (LATs) for hepatitis C virus (HCV) are under development as a strategy to improve linkage to care, treatment adherence and outcomes. We conducted a survey of HCV treatment prescribers and HCV policymakers in low- and middle-income countries (LMICs) regarding acceptability and feasibility of HCV LATs. We included one-time intramuscular injection, subdermal implant and transdermal patch as potential LAT options. We surveyed participants regarding optimal health system and patient characteristics, concerns, potential barriers, overall feasibility and preferences for HCV LAT as compared to daily oral medication. Overall, 122 providers and 50 policymakers from 42 LMICs completed the survey. Among providers, 93% (113/122) expressed willingness to prescribe LAT and 72% (88/120) of providers preferred LAT if provided at comparable efficacy, safety and cost as current oral treatments. Of providers preferring HCV LAT to daily oral medication, 67% (59/88) preferred injection, 24% (21/88) preferred patch and 9% (8/88) preferred implant. Only 20% (24/122) would prescribe LAT if it were more costly than oral treatment. In regression analysis, no provider characteristics were associated with preference for LAT over oral treatment. Policymakers reported high likelihood that LAT would be included in treatment guidelines (42/50; 84%) and national drug formularies (39/50; 78%) if efficacy, safety and cost were similar to oral treatment. HCV LATs could advance progress to HCV elimination in LMICs by diversifying treatment options to improve treatment coverage and outcomes. Provider preferences from LMICs are a critical consideration in the development of HCV LATs to ensure its early and equitable availability in LMICs.

Safety and pharmacokinetics of oral and long-acting injectable cabotegravir or long-acting injectable rilpivirine in virologically suppressed adolescents with HIV (IMPAACT 2017/MOCHA): a phase 1/2, multicentre, open-label, non-comparative, dose-finding study

BACKGROUND

Combined intramuscular long-acting cabotegravir and long-acting rilpivirine constitute the first long-acting combination antiretroviral therapy (ART) regimen approved for adults with HIV. The goal of the IMPAACT 2017 study (MOCHA [More Options for Children and Adolescents]) was to assess the safety and pharmacokinetics of these drugs in adolescents.

METHODS

In this phase 1/2, multicentre, open-label, non-comparative, dose-finding study, virologically suppressed adolescents (aged 12-17 years; weight ≥35 kg; BMI ≤31·5 kg/m2) with HIV-1 on daily oral ART were enrolled at 15 centres in four countries (Botswana, South Africa, Thailand, and the USA). After 4-6 weeks of oral cabotegravir (cohort 1C) or rilpivirine (cohort 1R), participants received intramuscular long-acting cabotegravir or long-acting rilpivirine every 4 weeks or 8 weeks per the adult dosing regimens, while continuing pre-study ART. The primary outcomes were assessments of safety measures, including all adverse events, until week 4 for oral cabotegravir and until week 16 for long-acting cabotegravir and long-acting rilpivirine, and pharmacokinetic measures, including the area under the plasma concentration versus time curve during the dosing interval (AUC0-tau) and drug concentrations, at week 2 for oral dosing of cabotegravir and at week 16 for intramuscular dosing of cabotegravir and rilpivirine. Enrolment into cohort 1C or cohort 1R was based on the participant's pre-study ART, meaning that masking was not done. For pharmacokinetic analyses, blood samples were drawn at weeks 2-4 after oral dosing and weeks 4-16 after intramuscular dosing. Safety outcome measures were summarised using frequencies, percentages, and exact 95% CIs; pharmacokinetic parameters were summarised using descriptive statistics. This trial is registered at ClinicalTrials.gov, NCT03497676, and is closed to enrolment.

FINDINGS

Between March 19, 2019, and Nov 25, 2021, 55 participants were enrolled: 30 in cohort 1C and 25 in cohort 1R. At week 16, 28 (97%, 95% CI 82-100) of the 29 dose-evaluable participants in cohort 1C and 21 (91%; 72-99) of the 23 dose-evaluable participants in cohort 1R had reported at least one adverse event, with the most common being injection-site pain (nine [31%] in cohort 1C; nine [39%] in cohort 1R; none were severe). One (4%, 95% CI 0-22) participant in cohort 1R had an adverse event of grade 3 or higher, leading to treatment discontinuation, which was defined as acute rilpivirine-related allergic reaction (self-limiting generalised urticaria) after the first oral dose. No deaths or life-threatening events occurred. In cohort 1C, the week 2 median cabotegravir AUC0-tau was 148·5 (range 37·2-433·1) μg·h/mL. The week 16 median concentrations for the every-4-weeks and every-8-weeks dosing was 3·11 μg/mL (range 1·22-6·19) and 1·15 μg/mL (<0·025-5·29) for cabotegravir and 52·9 ng/mL (31·9-148·0) and 39·1 ng/mL (27·2-81·3) for rilpivirine, respectively. These concentrations were similar to those in adults.

INTERPRETATION

Study data support using long-acting cabotegravir or long-acting rilpivirine, given every 4 weeks or 8 weeks, per the adult dosing regimens, in virologically suppressed adolescents aged 12 years and older and weighing at least 35 kg.

FUNDING

The National Institutes of Health and ViiV Healthcare.

Erratum to: Progress Note 2024: Curing HIV; Not in My Lifetime or Just Around the Corner?

[This corrects the article DOI: 10.20411/pai.v8i2.665.].

Asian participants' experience in phase 3/3b studies of long-acting cabotegravir and rilpivirine: Efficacy, safety, pharmacokinetic, and virological outcomes through week 96

OBJECTIVES

Cabotegravir + rilpivirine (CAB + RPV) dosed monthly or every 2 months is the first complete long-acting (LA) regimen recommended by treatment guidelines for the maintenance of HIV-1 virological suppression. This post hoc analysis summarizes outcomes for Asian participants through week 96.

METHODS

Data from Asian participants naive to CAB + RPV randomized to receive dosing every 4 weeks (Q4W) or every 8 weeks (Q8W) in the FLAIR (NCT02938520) and ATLAS-2M (NCT03299049) phase 3/3b studies were pooled. The proportion of participants with plasma HIV-1 RNA ≥50 and <50 copies/mL (per FDA Snapshot algorithm), incidence of confirmed virological failure (CVF; two consecutive HIV-1 RNA ≥200 copies/mL), pharmacokinetics, safety, and tolerability through week 96 were assessed.

RESULTS

Overall, 41 Asian participants received CAB + RPV (Q8W, n = 17; Q4W, n = 24). At week 96, 83% (n = 34/41) of participants maintained HIV-1 RNA <50 copies/mL, none had HIV-1 RNA ≥50 copies/mL, and 17% (n = 7/41) had no virological data. No Asian participant met the CVF criterion. Drug-related adverse events occurred in 44% (n = 18/41) of participants; none were Grade ≥3. All injection site reactions were Grade 1 or 2; median duration was 2 days and most resolved within 7 days (90%, n = 390/435). CAB and RPV trough concentrations remained well above their respective protein-adjusted 90% inhibitory concentrations (CAB, 0.166 μg/mL; RPV, 12 ng/mL) through week 96.

CONCLUSIONS

CAB + RPV LA demonstrated high efficacy, with no participants having CVF, and an acceptable safety profile in Asian participants through week 96. These data support CAB + RPV LA as a complete regimen for the maintenance of HIV-1 virological suppression in Asian individuals.

Implementation of a Pharmacist-Led, Long-Acting, Injectable Cabotegravir/Rilpivirine Program for HIV-1 at Health System-Based Clinics in the New York Metropolitan Area

Long-acting cabotegravir/rilpivirine (LA-CAB/RPV) is the first complete injectable antiretroviral for patients living with HIV. To facilitate patient access to long-acting injectable treatment, a system-wide, pharmacist-led, LA-CAB/RPV transition program was developed at four health system-based New York clinics. Provider referrals were received across four clinics between January 22nd, 2021, and December 31st, 2022. All referrals were evaluated by a pharmacist for clinical eligibility and medication access. The primary outcome was the treatment retention rate defined as the percentage of patients who remained on LA-CAB/RPV at 3 months post-transition. A total of 171 referrals were received, with 73 patients (43%) initiating LA-CAB/RPV. Baseline demographics included a median age of 38 years, 81% patients were male, 41% were African American, and 49% had commercial insurance coverage. The treatment retention rate was 90% at 3 months post-transition. By the end of the study period, 84% of patients who transitioned remained on LA-CAB/RPV. Treatment was discontinued due to reasons such as viral breakthrough (4%), emergence of mutations (4%), and intolerable side effects (4%). Injection site reactions were commonly reported (51%), but only resulting in treatment discontinuation for one patient. A pharmacist-led program can transition a diverse population of patients living with HIV to LA-CAB/RPV. Results from this study further add to clinical experiences with LA-CAB/RPV, demonstrating real-world treatment retention despite more frequent clinic visits for patients.

Progress Note 2024: Curing HIV; Not in My Lifetime or Just Around the Corner?

Once a death sentence, HIV is now considered a manageable chronic disease due to the development of antiretroviral therapy (ART) regimens with minimal toxicity and a high barrier for genetic resistance. While highly effective in arresting AIDS progression and rendering the virus untransmissible in people living with HIV (PLWH) with undetectable viremia (U=U) [1, 2]), ART alone is incapable of eradicating the "reservoir" of resting, latently infected CD4+ T cells from which virus recrudesces upon treatment cessation. As of 2022 estimates, there are 39 million PLWH, of whom 86% are aware of their status and 76% are receiving ART [3]. As of 2017, ART-treated PLWH exhibit near normalized life expectancies without adjustment for socioeconomic differences [4]. Furthermore, there is a global deceleration in the rate of new infections [3] driven by expanded access to pre-exposure prophylaxis (PrEP), HIV testing in vulnerable populations, and by ART treatment [5]. Therefore, despite outstanding issues pertaining to cost and access in developing countries, there is strong enthusiasm that aggressive testing, treatment, and effective viral suppression may be able to halt the ongoing HIV epidemic (ie, UNAIDS' 95-95-95 targets) [6-8]; especially as evidenced by recent encouraging observations in Sydney [9]. Despite these promising efforts to limit further viral transmission, for PLWH, a "cure" remains elusive; whether it be to completely eradicate the viral reservoir (ie, cure) or to induce long-term viral remission in the absence of ART (ie, control; Figure 1). In a previous salon hosted by Pathogens and Immunity in 2016 [10], some researchers were optimistic that a cure was a feasible, scalable goal, albeit with no clear consensus on the best route. So, how are these cure strategies panning out? In this commentary, 8 years later, we will provide a brief overview on recent advances and failures towards identifying determinants of viral persistence and developing a scalable cure for HIV. Based on these observations, and as in the earlier salon, we have asked several prominent HIV cure researchers for their perspectives.

Direct switch from an efavirenz-based regimen to intramuscular long-acting cabotegravir plus rilpivirine: A case report

Switching from oral antiretroviral treatment to intramuscular (IM) cabotegravir (CAB) + rilpivirine (RPV) has an optional oral lead-in to ensure tolerability. The British HIV Association guidelines advise against directly switching from oral antiretroviral (ART) combinations containing strong/moderate cytochrome inducers like efavirenz (EFV) to IM CAB + RPV. EFV has a prolonged elimination half-life, leading to a residual induction of UGT1A1 and CYP3A4 after discontinuation. These enzymes are responsible for CAB and RPV metabolism and their induction might lead to sub-optimal concentrations of CAB and RPV, risking drug resistance. When switching from EFV to oral CAB + RPV, the ATLAS and ATLAS 2M studies showed reduced RPV concentrations but with maintained viral suppression during the oral lead-in and subsequent long-acting injectable (LAI) phases. Also, a recent pharmacokinetic modelling study indicated reduced RPV concentrations, without viral implication, when switching from EFV to IM CAB + RPV. However, there are limited real-world data on direct switching from EFV-based therapy to long-acting IM CAB + RPV. We describe a case where oral intake was impossible in a critical care scenario, switching from emitricitabine/tenofovir-DF (FTC/TDF) 200/245 mg + 600 mg EFV to IM CAB + RPV for treatment optimisation.

Fighting nature with nature: antiviral compounds that target retroviruses

The human immunodeficiency virus (HIV) is a type of lentivirus that targets the human immune system and leads to acquired immunodeficiency syndrome (AIDS) at a later stage. Up to 2021, there are millions still living with HIV and many have lost their lives. To date, many anti-HIV compounds have been discovered in living organisms, especially plants and marine sponges. However, no treatment can offer a complete cure, but only suppressing it with a life-long medication, known as combined antiretroviral therapy (cART) or highly active antiretroviral therapy (HAART) which are often associated with various adverse effects. Also, it takes many years for a discovered compound to be approved for clinical use. Thus, by employing advanced technologies such as automation, conducting systematic screening and testing protocols may boost the discovery and development of potent and curative therapeutics for HIV infection/AIDS. In this review, we aim to summarize the antiretroviral therapies/compounds and their associated drawbacks since the discovery of azidothymidine. Additionally, we aim to provide an updated analysis of the most recent discoveries of promising antiretroviral candidates, along with an exploration of the current limitations within antiretroviral research. Finally, we intend to glean insightful perspectives and propose future research directions in this crucial area of study.

HIV epidemiology, prevention, treatment, and implementation strategies for public health

The global HIV response has made tremendous progress but is entering a new phase with additional challenges. Scientific innovations have led to multiple safe, effective, and durable options for treatment and prevention, and long-acting formulations for 2-monthly and 6-monthly dosing are becoming available with even longer dosing intervals possible on the horizon. The scientific agenda for HIV cure and remission strategies is moving forward but faces uncertain thresholds for success and acceptability. Nonetheless, innovations in prevention and treatment have often failed to reach large segments of the global population (eg, key and marginalised populations), and these major disparities in access and uptake at multiple levels have caused progress to fall short of their potential to affect public health. Moving forward, sharper epidemiologic tools based on longitudinal, person-centred data are needed to more accurately characterise remaining gaps and guide continued progress against the HIV epidemic. We should also increase prioritisation of strategies that address socio-behavioural challenges and can lead to effective and equitable implementation of existing interventions with high levels of quality that better match individual needs. We review HIV epidemiologic trends; advances in HIV prevention, treatment, and care delivery; and discuss emerging challenges for ending the HIV epidemic over the next decade that are relevant for general practitioners and others involved in HIV care.

Pharmacokinetics and tolerability of cabotegravir and rilpivirine long-acting intramuscular injections to the vastus lateralis (lateral thigh) muscles of healthy adult participants

Cabotegravir + rilpivirine administered via intramuscular gluteal injections is the first complete long-acting (LA) regimen approved for maintaining HIV-1 virologic suppression. The vastus lateralis (lateral) thigh muscle could be a potential alternative site of administration in circumstances such as injection site fatigue, intolerability, or contraindication for gluteal administration. Cabotegravir and rilpivirine pharmacokinetics and participant tolerability were evaluated following single intramuscular injections to the lateral thigh. Healthy adult participants received 4 weeks of daily oral cabotegravir (30 mg) and rilpivirine (25 mg), followed by a 10- to 14-day washout and single 3 mL intramuscular injections of cabotegravir LA 600 mg and rilpivirine LA 900 mg to the lateral thigh. Safety, tolerability, and pharmacokinetics were evaluated through 52 weeks post injection. Pharmacokinetic parameters were estimated using non-compartmental analysis. Fifteen participants (female at birth, n = 6) enrolled. Median age was 33 years. Median weight was 93.6 kg. Median body mass index was 31.4 kg/m2. One participant withdrew due to pregnancy after oral dosing before receiving an injection. Plasma concentrations at Weeks 4 and 8 were 15.4- and 5.3-fold above the protein-adjusted 90% inhibitory concentration for cabotegravir and 4.7- and 2.4-fold for rilpivirine, respectively. The most common injection site reactions were pain [28/28 (100%)], induration [15/28 (54%)], and swelling [12/28 (42%)]; 94% were Grade 1 or 2. Cabotegravir and rilpivirine plasma pharmacokinetic profiles observed in this study support further evaluation of thigh administration in target populations of people living with HIV-1. Tolerability of cabotegravir + rilpivirine LA intramuscular lateral thigh injections was similar to gluteal administration.

Predictors of Post-switch Viremia in People With HIV on Injectable Cabotegravir/Rilpivirine

BACKGROUND

Predictors of virologic failure in those receiving long-acting injectable (LAI) cabotegravir/rilpivirine (CAB/RPV) have been evaluated; however, factors associated with low-level viremia, including blips and persistent low-level viremia (pLLV), are not well-described.

METHODS

A retrospective cohort study was performed using data from April 2021 through December 2022. Inclusion criteria included treatment with CAB/RPV for at least 3 months, availability of pre- and postswitch HIV RNA values, HIV RNA value of <200 copies/mL (cpm) at the time of switch to CAB/RPV, and at least 1 postswitch HIV RNA collected >21 days after the start of CAB/RPV. Outcomes included incidence of HIV RNA ≥20, ≥50, and ≥200 cpm after switch and factors associated with detectable HIV RNA after switch.

RESULTS

The median duration of follow-up among 144 participants was 287 days. After switching to CAB/RPV, occurrences of at least 1 HIV RNA ≥20, ≥50, and ≥200 cpm after switch were 34.7%, 15.3%, and 2.8%, respectively. Those with pLLV before switch were significantly more likely to have detectable HIV RNA after switch [hazard ratio 24.39 (8.71-68.34)], and 44.4% of those with pLLV before switch continued with pLLV after switch to LAI CAB/RPV. Body mass index, late injection, and monthly versus every two-month dosing were not associated with detectable viremia after switch.

CONCLUSIONS

Despite virologic suppression at the time of switch and the perceived adherence benefits, participants still experienced blips or pLLV after switch to LAI CAB/RPV. Having detectable HIV RNA on oral therapy before switch was associated with detectable HIV RNA after switching.

[Current antiretroviral therapy: A review]

The article presents an overview of clinical recommendations for currant antiretroviral therapy. Currently, the current preferred first-line antiretroviral therapy regimens are combinations of 2 or 3 antiretroviral drugs (ARVs) in one tablet with a frequency of administration 1 time per day and, as a rule, include drugs of the 2nd generation (integrase inhibitors or non-nucleoside reverse transcriptase inhibitors). These schemes have high efficiency and a good genetic barrier in the development of HIV resistance mutations. HIV protease inhibitors are used as alternative regimens. Schemes with the least number and spectrum of side effects, no effect on metabolic processes and minimal drug interactions have advantages. Switching patients to injectable therapy regimens with a frequency of administration of drugs once every 2 months can significantly improve the quality of life of patients and, accordingly, adherence to their treatment. The development and introduction of new classes of ARVs into clinical practice ensures the suppression of HIV replication in most patients with HIV strains resistant to drugs of the main groups of ARVs (nucleoside/nucleotide reverse transcriptase.

Physiologically Based Pharmacokinetic Modelling of Cabotegravir Microarray Patches in Rats and Humans

Microarray patches (MAPs) are currently under investigation as a self-administered, pain-free alternative used to achieve long-acting (LA) drug delivery. Cabotegravir is a potent antiretroviral that has demonstrated superior results over current pre-exposure prophylaxis (PrEP) regimens. This study aimed to apply physiologically based pharmacokinetic (PBPK) modelling to describe the pharmacokinetics of the dissolving bilayer MAP platform and predict the optimal dosing strategies for a once-weekly cabotegravir MAP. A mathematical description of a MAP was implemented into a PBPK model, and empirical models were utilised for parameter estimation. The intradermal PBPK model was verified against previously published in vivo rat data for intramuscular (IM) and MAP administration, and in vivo human data for the IM administration of LA cabotegravir. The verified model was utilised for the prediction of 300 mg, 150 mg and 75 mg once-weekly MAP administration in humans. Cabotegravir plasma concentrations >4 × protein-adjusted 90% inhibitory concentration (PA-IC90) (0.664 µg/mL) and >8 × PA-IC90 (1.33 µg/mL) were set as targets. The 75 mg, 150 mg and 300 mg once-weekly cabotegravir MAP regimens were predicted to sustain plasma concentrations >4 × PA-IC90, while the 300 mg and 150 mg regimens achieved plasma concentrations >8 × PA-IC90. These data demonstrate the potential for a once-weekly cabotegravir MAP using practical patch sizes for humans and inform the further development of cabotegravir MAPs for HIV PrEP.

Clair M, Polli JW, Vanveggel S, Vandermeulen K, D’Amico R, Garges HP, Zolopa A, Spreen WR, van Wyk J, Cutrell AG. Expanded Multivariable Models to Assist Patient Selection for Long-Acting Cabotegravir + Rilpivirine Treatment: Clinical Utility of a Combination of Patient, Drug Concentration, and Viral Factors Associated With Virologic Failure

BACKGROUND

Previously reported post hoc multivariable analyses exploring predictors of confirmed virologic failure (CVF) with cabotegravir + rilpivirine long-acting (CAB + RPV LA) were expanded to include data beyond week 48, additional covariates, and additional participants.

METHODS

Pooled data from 1651 participants were used to explore dosing regimen (every 4 or every 8 weeks), demographic, viral, and pharmacokinetic covariates as potential predictors of CVF. Prior dosing regimen experience was accounted for using 2 populations. Two models were conducted in each population-baseline factor analyses exploring factors known at baseline and multivariable analyses exploring baseline factors plus postbaseline model-predicted CAB/RPV trough concentrations (4 and 44 weeks postinjection). Retained factors were evaluated to understand their contribution to CVF (alone or in combination).

RESULTS

Overall, 1.4% (n = 23/1651) of participants had CVF through 152 weeks. The presence of RPV resistance-associated mutations, human immunodeficiency virus-1 subtype A6/A1, and body mass index ≥30 kg/m2 were associated with an increased risk of CVF (P < .05 adjusted incidence rate ratio), with participants with ≥2 of these baseline factors having a higher risk of CVF. Lower model-predicted CAB/RPV troughs were additional factors retained for multivariable analyses.

CONCLUSIONS

The presence of ≥2 baseline factors (RPV resistance-associated mutations, A6/A1 subtype, and/or body mass index ≥30 kg/m2) was associated with increased CVF risk, consistent with prior analyses. Inclusion of initial model-predicted CAB/RPV trough concentrations (≤first quartile) did not improve the prediction of CVF beyond the presence of a combination of ≥2 baseline factors, reinforcing the clinical utility of the baseline factors in the appropriate use of CAB + RPV LA.

Assessing readiness to implement long-acting injectable HIV antiretroviral therapy: provider and staff perspectives

BACKGROUND

Long-acting injectable antiretroviral therapy (LAI-ART) represents the next innovation in HIV therapy. Pre-implementation research is needed to develop effective strategies to ensure equitable access to LAI-ART to individuals living with HIV.

METHODS

We conducted focus group discussions (FGDs) with providers and staff affiliated with HIV clinics in San Francisco, Chicago, and Atlanta to understand barriers to and facilitators of LAI-ART implementation. Participants also completed a short survey about implementation intentions. FGDs were held via video conference, recorded, transcribed, and thematically analyzed using domains associated with the Consolidated Framework for Implementation Research (CFIR).

RESULTS

Between September 2020 and April 2021, we led 10 FDGs with 49 participants, of whom ~60% were prescribing providers. Organizational readiness for implementing change was high, with 85% agreeing to being committed to figuring out how to implement LAI-ART. While responses were influenced by the unique inner and outer resources available in each setting, several common themes, including implementation mechanisms, dominated: (1) optimism and enthusiasm about LAI-ART was contingent on ensuring equitable access to LAI-ART; (2) LAI-ART shifts the primary responsibility of ART adherence from the patient to the clinic; and (3) existing clinic systems require strengthening to meet the needs of patients with adherence challenges. Current systems in all sites could support the use of LAI-ART in a limited number of stable patients. Scale-up and equitable use would be challenging or impossible without additional personnel. Participants outlined programmatic elements necessary to realize equitable access including centralized tracking of patients, capacity for in-depth, hands-on outreach, and mobile delivery of LAI-ART. Sites further specified unknown logistical impacts on implementation related to billing/payer source as well as shipping and drug storage.

CONCLUSIONS

Among these HIV care sites, clinic readiness to offer LAI-ART to a subset of patients is high. The main challenges to implementation include concerns about unequal access and a recognition that strengthening the clinic system is critical.

The New Era of Long-Acting Antiretroviral Therapy: When and Why to Make the Switch

PURPOSE OF REVIEW

Despite the availability of safe and effective oral combination antiretroviral therapy, barriers to maintaining viral suppression remain a challenge to ending the HIV epidemic. Long-acting injectable antiretroviral therapy was developed as an alternative to daily oral therapy. This review summarizes the current literature on the efficacy of long-acting cabotegravir plus rilpivirine for the treatment of HIV-1, reasons to switch to injectable therapy, and barriers to switching.

RECENT FINDINGS

Long-acting cabotegravir plus rilpivirine is safe and effective in maintaining HIV-1 virologic suppression. Ideal candidates for switching to long-acting cabotegravir plus rilpivirine are virologically suppressed on oral regimens with good adherence and no history of virologic failure or baseline resistance. Indications to switch to injectable therapy include patient preference, the potential for improved adherence, and avoidance of adverse effects. Implementation research is needed to assess and overcome system barriers. Long-acting cabotegravir plus rilpivirine is a novel alternative to oral antiretrovirals, with the potential to improve adherence and quality of life in people with HIV.

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

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

Repurposing of rilpivirine for preventing platelet β3 integrin-dependent thrombosis by targeting c-Src active autophosphorylation

BACKGROUND

HIV-infected individuals are known to be at higher risk for thrombotic cardiovascular disease (CVD), which may also be differentially affected by components of anti-HIV drugs. To identify the effects of a series of FDA-approved anti-HIV drugs on platelet aggregation in humans, focusing on the novel pharmacological effects of rilpivirine (RPV), a reverse transcriptase inhibitor, on platelet function both in vitro and in vivo and the mechanisms involved.

METHODS AND RESULTS

In vitro studies showed that RPV was the only anti-HIV reagent that consistently and efficiently inhibited aggregation elicited by different agonists, exocytosis, morphological extension on fibrinogen, and clot retraction. Treatment of mice with RPV significantly prevented thrombus formation in FeCl3-injured mesenteric vessels, postcava with stenosis surgery, and ADP -induced pulmonary embolism models without defects in platelet viability, tail bleeding, and coagulation activities. RPV also improved cardiac performance in mice with post-ischemic reperfusion. A mechanistic study revealed that RPV preferentially attenuated fibrinogen-stimulated Tyr773 phosphorylation of β3-integrin by inhibiting Tyr419 autophosphorylation of c-Src. Molecular docking and surface plasmon resonance analyses showed that RPV can bind directly to c-Src. Further mutational analysis showed that the Phe427 residue of c-Src is critical for RPV interaction, suggesting a novel interaction site for targeting c-Src to block β3-integrin outside-in signaling.

CONCLUSION

These results demonstrated that RPV was able to prevent the progression of thrombotic CVDs by interrupting β3-integrin-mediated outside-in signaling via inhibiting c-Src activation without hemorrhagic side effects, highlighting RPV as a promising reagent for the prevention and therapy of thrombotic CVDs.

Efficacy, safety, and tolerability of switching to long-acting cabotegravir plus rilpivirine versus continuing fixed-dose bictegravir, emtricitabine, and tenofovir alafenamide in virologically suppressed adults with HIV, 12-month results (SOLAR): a randomised, open-label, phase 3b, non-inferiority trial

BACKGROUND

Cabotegravir plus rilpivirine is the only approved complete long-acting regimen for the maintenance of HIV-1 virological suppression dosed every 2 months. The SOLAR study aimed to compare long-acting cabotegravir plus rilpivirine every 2 months with continued once-daily bictegravir, emtricitabine, and tenofovir alafenamide for the maintenance of HIV-1 virological suppression in adults living with HIV.

METHODS

SOLAR is a randomised, open-label, multicentre, phase 3b, non-inferiority study. The study was done in 118 centres across 14 countries. Participants with HIV-1 RNA less than 50 copies per mL were randomly assigned (2:1), stratified by sex at birth and BMI, to either long-acting cabotegravir (600 mg) plus rilpivirine (900 mg) dosed intramuscularly every 2 months or to continue daily oral bictegravir (50 mg), emtricitabine (200 mg), and tenofovir alafenamide (25 mg). Participants randomly assigned to long-acting therapy had a choice to receive cabotegravir (30 mg) plus rilpivirine (25 mg) once daily as an optional oral lead-in for approximately 1 month. The primary efficacy endpoint was the proportion of participants with virological non-response (HIV-1 RNA ≥50 copies per mL; the US Food and Drug Administration snapshot algorithm, 4% non-inferiority margin; modified intention-to-treat exposed population) at month 11 (long-acting start with injections group) and month 12 (long-acting with oral lead-in group and bictegravir, emtricitabine, and tenofovir alafenamide group). The study is registered with ClinicalTrials.gov, NCT04542070, and is ongoing.

FINDINGS

837 participants were screened between Nov 9, 2020, and May 31, 2021, and 687 were randomly assigned to switch treatment or continue existing treatment. Of 670 participants (modified intention-to-treat exposed population), 447 (67%) switched to long-acting therapy (274 [61%] of 447 start with injections; 173 [39%] of 447 with oral lead-in) and 223 (33%) continued bictegravir, emtricitabine, and tenofovir alafenamide. Baseline characteristics were similar; median age was 37 years (range 18-74), 118 (18%) of 670 were female sex at birth, 207 (31%) of 670 were non-White, and median BMI was 25·9 kg/m2 (IQR 23·3-29·5). At month 11-12, long-acting cabotegravir plus rilpivirine showed non-inferior efficacy versus bictegravir, emtricitabine, and tenofovir alafenamide (HIV-1 RNA ≥50 copies per mL, five [1%] of 447 vs one [<1%] of 223), with an adjusted treatment difference of 0·7 (95% CI -0·7 to 2·0). Excluding injection site reactions, adverse events and serious adverse events were similar between groups. No treatment-related deaths occurred. More long-acting group participants had adverse events leading to withdrawal (25 [6%] of 454 vs two [1%] of 227). Injection site reactions were reported by 316 (70%) of 454 long-acting participants; most (98%) were grade 1 or 2.

INTERPRETATION

These data support the use of long-acting cabotegravir plus rilpivirine dosed every 2 months as a complete antiretroviral regimen that has similar efficacy to a commonly used integrase strand transfer inhibitor-based first-line regimen, while addressing unmet psychosocial issues associated with daily oral treatment.

FUNDING

ViiV Healthcare.

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

BACKGROUND

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Demonstration Project of Long-Acting Antiretroviral Therapy in a Diverse Population of People With HIV

BACKGROUND

Intramuscular cabotegravir (CAB) and rilpivirine (RPV) is the only long-acting antiretroviral therapy (LA-ART) regimen approved for people with HIV (PWH). Long-acting ART holds promise for improving outcomes among populations with barriers to adherence but is only approved for PWH who have virologic suppression with use of oral ART before initiating injectables.

OBJECTIVE

To examine LA-ART in a population of PWH that includes those with viremia.

DESIGN

Observational cohort study.

SETTING

Urban academic safety-net HIV clinic.

PATIENTS

Publicly insured adults living with HIV with and without viral suppression, high rates of unstable housing, mental illness, and substance use.

INTERVENTION

Demonstration project of long-acting injectable CAB-RPV.

MEASUREMENTS

Descriptive statistics summarizing cohort outcomes to date, based on pharmacy team logs and electronic medical record data.

RESULTS

Between June 2021 and November 2022, 133 PWH at the Ward 86 HIV Clinic were started on LA-ART, 76 of whom had virologic suppression while using oral ART and 57 of whom had viremia. The median age was 46 years (IQR, 25 to 68 years); 117 (88%) were cisgender men, 83 (62%) had non-White race, 56 (42%) were experiencing unstable housing or homelessness, and 45 (34%) had substance use. Among those with virologic suppression, 100% (95% CI, 94% to 100%) maintained suppression. Among PWH with viremia, at a median of 33 days, 54 of 57 had viral suppression, 1 showed the expected 2-log10 reduction in HIV RNA level, and 2 experienced early virologic failure. Overall, 97.5% (CI, 89.1% to 99.8%) were projected to achieve virologic suppression by a median of 33 weeks. The current virologic failure rate of 1.5% in the cohort is similar to that across registrational clinical trials at 48 weeks.

LIMITATION

Single-site study.

CONCLUSION

This project demonstrates the ability of LA-ART to achieve virologic suppression among PWH, including those with viremia and challenges to adherence. Further data on the ability of LA-ART to achieve viral suppression in people with barriers to adherence are needed.

PRIMARY FUNDING SOURCE

National Institutes of Health, City and County of San Francisco, and Health Resources and Services Administration.

Acceptability, Feasibility, and Appropriateness of Implementation of Long-acting Injectable Antiretrovirals: A National Survey of Ryan White Clinics in the United States

Background

The approval of long-acting injectable cabotegravir/rilpivirine (LAI CAB/RPV) heightened the urgency of ensuring effective implementation. Our study assesses readiness and barriers to implement LAI CAB/RPV across Ryan White-funded clinics in the United States.

Methods

We conducted a cross-sectional survey between December 2020 and January 2021 using validated 4-item measures: acceptability of intervention measure (AIM), intervention appropriateness measure (IAM), and feasibility of intervention measure (FIM). Associations between measures and clinic characteristics were evaluated via Spearman rank correlations. A 5-point Likert scale ranked potential barriers of implementation responses. Open-ended questions were analyzed through a thematic approach.

Results

Of 270 clinics, 44 (16%) completed the survey: 38% federally qualified health centers, 36% academic, 20% community-based organizations, 14% hospital outpatient, and 9% nonprofit. Means (SD; range) were as follows: AIM, 17.6 (2.4; 12-20); IAM, 17.6 (2.4; 13-20); and FIM, 16.8 (2.9; 7-20). Twenty percent were not at all ready to implement LAI CAB/RPV, and 52% were slightly or somewhat ready. There was a significant association between AIM and the proportion of Medicaid patients (AIM, rho = 0.312, P = .050). Community-based organizations scored the highest readiness measures (mean [SD]: AIM, 19.50 [1.41]; IAM, 19.25 [1.49]; FIM, 19.13 [1.36]) as compared with other clinics. Implementation barriers were cost and patients' nonadherence to visits.

Conclusions

There is variability of readiness yet high levels of perceived acceptability and appropriateness of implementing LAI CAB/RPV among Ryan White clinics, necessitating tailored interventions for successful implementation. A special focus on addressing the barriers of adherence and the cost of implementation is needed.

Prodrug approaches for the development of a long-acting drug delivery systems

Long-acting formulations are designed to reduce dosing frequency and simplify dosing schedules by providing an extended duration of action. One approach to obtain long-acting formulations is to combine long-acting prodrugs (LA-prodrug) with existing or emerging drug delivery technologies (DDS). The design criteria for long-acting prodrugs are distinct from conventional prodrug strategies that alter absorption, distribution, metabolism, and excretion (ADME) parameters. Our review focuses on long-acting prodrug delivery systems (LA-prodrug DDS), which is a subcategory of long-acting formulations where prodrug design enables DDS formulation to achieve an extended duration of action that is greater than the parent drug. Here, we define LA-prodrugs as the conjugation of an active pharmaceutical ingredient (API) to a promoiety group via a cleavable covalent linker, where both the promoiety and linker are selected to enable formulation and administration from a drug delivery system (DDS) to achieve an extended duration of action. These LA-prodrug DDS results in an extended interval where the API is within a therapeutic range without necessarily altering ADME as is typical of conventional prodrugs. The conversion of the LA-prodrug to the API is dependent on linker cleavage, which can occur before or after release from the DDS. The requirement for linker cleavage provides an additional tool to prolong release from these LA-prodrug DDS. In addition, the physicochemical properties of drugs can be tuned by promoiety selection for a particular DDS. Conjugation with promoieties that are carriers or amenable to assembly into carriers can also provide access to formulations designed for extending duration of action. LA-prodrugs have been applied to a wide variety of drug delivery strategies and are categorized in this review by promoiety size and complexity. Small molecule promoieties (typically MW < 1000 Da) have been used to improve encapsulation or partitioning as well as broaden APIs for use with traditional long-acting formulations such as solid drug dispersions. Macromolecular promoieties (typically MW > 1000 Da) have been applied to hydrogels, nanoparticles, micelles, dendrimers, and polymerized prodrug monomers. The resulting LA-prodrug DDS enable extended duration of action for active pharmaceuticals across a wide range of applications, with target release timescales spanning days to years.

Impact of rilpivirine cross-resistance on long-acting cabotegravir-rilpivirine in low and middle-income countries

Baseline rilpivirine drug resistance mutations (DRMs) are a risk factor for virological failure in patients treated with long-acting cabotegravir and rilpivirine (CAB/RPV LA). We investigated rilpivirine cross-resistance in treatment-naive and experienced patients in South Africa. One in 10 treatment-naive patients and 74.5% of patients failing treatment presented with rilpivirine DRMs. Our data suggest targeted genotyping may be required for patients initiating CAB/RPV LA, which significantly complicates the currently used public health approach.

Long-acting antiretrovirals and HIV treatment adherence

Intramuscular injection of long-acting cabotegravir and rilpivirine is a novel, long-acting antiretroviral therapy (ART) combination approved for use as a fully suppressive regimen for people living with HIV. Long-acting cabotegravir with rilpivirine ART has reduced required dosing frequency from once daily to once every month or every 2 months injections. This new era of long-acting ART, which includes other antiretrovirals and formulations in various stages of clinical development, holds tremendous promise to change the standard of HIV treatment. Although long-acting ART has high potential to be revolutionary in the landscape of HIV care, prevention, and treatment cascade, more data are needed to substantiate its efficacy and cost-effectiveness among patients at risk of non-adherence and across age groups, pregnancy, and post partum. Advocacy efforts and policy changes to optimise a sustained, high-quality, equitable reach of long-acting ART, especially in low-income and middle-income countries where most people living with HIV reside, are needed to realise the full benefits of long-acting ART.

Future of Antiretroviral Drugs and Evolution of HIV-1 Drug Resistance

Highly active antiretroviral (ARV) therapy has been used for many years, but the use in low- and middle-income countries of antiretroviral drugs with low genetic barrier to resistance, combined with limited availability of viral load testing, has led to higher rates of acquired drug resistance, sustaining the rate of transmitted drug resistance. Here, we describe the evolution of ARV drugs with the ongoing development of injectable long-acting forms and the requirements regarding all new ARV drugs (i.e., no transmitted drug resistance, no cross-resistance and high genetic barrier to resistance). Then, we report the evolution of both transmitted and acquired resistance regarding new ARV drugs. The WHO has set very ambitious but motivating goals for HIV testing, treatment and viral suppression, aiming to achieve rates of 95% for all three by 2025. Reaching these goals requires a wide implementation and use of close virological monitoring in LMICs.

First Demonstration Project of Long-Acting Injectable Antiretroviral Therapy for Persons With and Without Detectable Human Immunodeficiency Virus (HIV) Viremia in an Urban HIV Clinic

BACKGROUND

Long-acting injectable antiretroviral therapy (LAI-ART) is approved for treatment-naive or experienced people with human immunodeficiency virus (HIV; PWH) based on trials that only included participants with viral suppression. We performed the first LAI-ART demonstration project to include PWH unable to achieve or maintain viral suppression due to challenges adhering to oral ART.

METHODS

Ward 86 is a large HIV clinic in San Francisco that serves publicly insured and underinsured patients. We started patients on LAI-ART via a structured process of provider referral, multidisciplinary review (MD, RN, pharmacist), and monitoring for on-time injections. Inclusion criteria were willingness to receive monthly injections and a reliable contact method.

RESULTS

Between June 2021 and April 2022, 51 patients initiated LAI-ART, with 39 receiving at least 2 follow-up injections by database closure (median age, 46 years; 90% cisgender men, 61% non-White, 41% marginally housed, 54% currently using stimulants). Of 24 patients who initiated injections with viral suppression (median CD4 cell count, 706 cells/mm3), 100% (95% confidence interval [CI], 86%-100%) maintained viral suppression. Of 15 patients who initiated injections with detectable viremia (median CD4 cell count, 99 cells/mm3; mean log10 viral load, 4.67; standard deviation, 1.16), 12 (80%; 95% CI, 55%-93%) achieved viral suppression, and the other 3 had a 2-log viral load decline by a median of 22 days.

CONCLUSIONS

This small demonstration project of LAI-ART in a diverse group of patients with high levels of substance use and marginal housing demonstrated promising early treatment outcomes, including in those with detectable viremia due to adherence challenges. More data on LAI-ART in hard-to-reach populations are needed.

Long-acting injectable antiretroviral therapy: will it change the future of HIV treatment?

The treatment of human immunodeficiency virus (HIV) has greatly advanced over the past few decades from complex regimens, with high toxicities, multiple daily dosing, and incomplete viral suppression to more simplified, highly effective, daily oral regimens. Although these advancements greatly improved access and tolerability, the need for daily antiretroviral (ARV) administration remained until recently. With long-acting (LA) injectable ARV options emerging, patients may choose how they want to receive treatment. By eliminating the barrier of daily medication adherence, LA injectable ARV formulations have the potential to not only improve health outcomes for the individual, but also the community by reducing HIV transmission. At the time of this writing cabotegravir/rilpivirine (LA-CAB/RPV) is the only LA injectable ARV regimen approved as a complete regimen for the treatment of HIV in adults and adolescents (⩾35 kg and ⩾12 years of age) who are virologically suppressed. However, additional studies of LA-CAB/RPV in expanded populations, and of other LA ARVs, are underway. The goal of this article was to summarize clinical data and review pertinent clinical considerations for the use of LA-CAB/RPV in the management of HIV.

Safety and efficacy of long-acting intramuscular cabotegravir and rilpivirine in adults with HIV-1 infection: a systematic review and meta-analysis protocol

BACKGROUND

Current antiretroviral regimens have, for the most part, achieved optimal antiretroviral efficacy and tolerability, transforming HIV infection from a deadly disease into a manageable chronic condition. However, adherence to daily oral drug intake remains an issue, as it is the most important determinant for sustained viral suppression and prevention of the emergence of drug-resistant viral strains. The long-acting injection antiretroviral cabotegravir and rilpivirine combination, a novel drug delivery approach, is about to revolutionise the therapy for people living with HIV. In this protocol, we aim to generate a clinically useful summary of the interventions based on their efficacy.

METHODS AND ANALYSIS

We searched the literature for eligible studies published from inception up to 16 August 2022 through PubMed, EMBASE, Cochrane Library, Scopus and ClinicalTrials.gov. Two methodologically trained researchers will select the qualified studies for data extraction independently. Cochrane Risk of Bias tool will be used to assess the risk of bias in included studies. Statistical heterogeneity will be computed by Cochrane X² and I² tests. Sensitivity analysis will be conducted to evaluate the stability of the results. Publication biases will be evaluated by Begg's and Egger's tests. The quality of evidence will be assessed by the Grading of Recommendations Assessment, Development and Evaluation system. The RevMan V.5.3 and Stata V.14.0 software will be applied for statistical analyses.

ETHICS AND DISSEMINATION

Ethical approval will not be required for this systematic review because the data used are not linked to the individual patient. The results of this review will be disseminated by being published in a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42022310414.

Two-drug regimens for HIV treatment

Combination therapy with three antiretroviral agents has been integral to successful HIV-1 treatment since 1996. Although the efficacy, adverse effects, and toxicities of contemporary three-drug regimens have improved, even the newest therapies have potential adverse effects. The use of two-drug regimens is one way to reduce lifetime exposure to antiretroviral drugs while maintaining the benefits of viral suppression. Multiple large, randomised trials have shown the virological non-inferiority of certain two-drug regimens versus three-drug comparators, including adverse effect differences that reflect known profiles of the antiretroviral drugs in the respective regimens. Two-drug combinations are now recommended in treatment guidelines and include the first long-acting antiretroviral regimen for the treatment of HIV-1. Recommended two-drug regimens differ in their risks for, and factors associated with, virological failure and emergent resistance. The tolerability, safety, metabolic profiles, and drug interactions of two-drug regimens also vary by the constituent drugs. No current two-drug regimen is recommended for people with chronic hepatitis B virus as none include tenofovir. Two-drug regimens have increased options for individualised care.

Barriers to Uptake of Long-Acting Antiretroviral Products for Treatment and Prevention of HIV in Low- and Middle-Income Countries (LMICs)

Long-acting injectable antiretroviral therapy (LA ART) has been found to be non-inferior to daily oral ART in phase 3 clinical trials and is poised to soon enter routine clinical care. This treatment modality has the potential to address many barriers to daily oral ART adherence among people living with human immunodeficiency virus (HIV) and for HIV Pre-Exposure prevention. Data from the Patient Reported Outcomes (PROs) showed high rates of satisfaction, acceptability, tolerability and preference for the LA regimen, compared with the daily oral treatment. Once LA ART is available, access and uptake will be limited because of current knowledge gaps in the use of these agents and multiple challenges many specific to low-income and middle-income countries, where the epidemic is most concentrated and HIV prevention and treatment options are limited. These gaps will lead to multiple systems-level and individual-level barriers to implementation. Anticipating and addressing these gaps and barriers will help fulfill the promise of these agents against the pandemic.

Barriers to Uptake of Long-Acting Antiretroviral Products for Treatment and Prevention of Human Immunodeficiency Virus (HIV) in High-Income Countries

Long-acting injectable antiretroviral therapy (LAI-ART) for the treatment and prevention of human immunodeficiency virus (HIV) holds great potential to shift treatment paradigms by offering an alternative to daily oral medication. However, significant challenges at the drug, patient, and system levels risk impeding the uptake and implementation of LAI-ART. This review aims to describe the known and anticipated barriers to uptake of LAI-ART in high-income countries, as well as the ongoing research addressing some of these barriers to improve the delivery and uptake of LAI-ART products.

Pregnancy outcomes and pharmacokinetics in pregnant women living with HIV exposed to long‐acting cabotegravir and rilpivirine in clinical trials

BACKGROUND

Limited data exist on pregnant women living with HIV exposed to cabotegravir + rilpivirine (CAB + RPV). Outcomes in pregnant participants exposed to CAB + RPV, and pharmacokinetic washout data in those exposed to CAB + RPV long-acting (LA) with live births, are presented.

METHODS

Women exposed to one or more doses of CAB + RPV (oral/LA) from ViiV Healthcare-sponsored phase 2b/3/3b clinical trials and the compassionate use programme who became pregnant were included. Upon pregnancy in the trial programme, CAB + RPV was discontinued, an alternative antiretroviral regimen was initiated, and quarterly pharmacokinetic sampling for 52 weeks post-last injection was obtained. CAB + RPV continuation or alternative antiretroviral regimen initiation was decided by pregnant compassionate use programme participants and their treating physicians.

RESULTS

As of 31 March 2021, 25 pregnancies following CAB + RPV exposure at conception were reported (five oral, 20 LA), including four who conceived during pharmacokinetic washout following treatment discontinuation. There were eight elective abortions, six miscarriages (five in first trimester), one ectopic pregnancy, and 10 live births (one oral, nine LA), including one infant born with congenital ptosis. Among participants exposed to CAB + RPV LA at conception with live births, plasma CAB and RPV washout concentrations during pregnancy were within the range of those observed in non-pregnant women.

CONCLUSION

In this first analysis of pregnancy outcomes following CAB + RPV exposure at conception, 10 live births, including one with congenital anomaly, were reported. Plasma CAB and RPV washout concentrations during pregnancy were within the range of those in non-pregnant women. Pregnancy surveillance within ViiV Healthcare-sponsored clinical trials is ongoing, with dedicated pregnancy studies planned.

Antiviral drugs

In this chapter, we have reviewed side effects reported with the use of antivirals for the treatment of the following infections: coronavirus disease 2019 (COVID-19), cytomegalovirus (CMV), hepatitis B virus (HBV), hepatitis C Virus (HCV), herpes simplex viruses 1 and 2 (HSV-1, -2), human immunodeficiency virus (HIV), and influenza virus. The search engines PUBMED, EMBASE and International Pharmaceutical Abstracts (IPA) were utilized to identify literature published between January 1, 2021 to December 31, 2021.

Molecular Epidemiology of HIV-1 in Eastern Europe and Russia

The HIV epidemic in Eastern Europe and Russia is large and not well-controlled. To describe the more recent molecular epidemiology of HIV-1, transmitted drug resistance, and the relationship between the epidemics in this region, we sequenced the protease and reverse transcriptase genes of HIV-1 from 812 people living with HIV from Ukraine (n = 191), Georgia (n = 201), and Russia (n = 420) before the initiation of antiretroviral therapy. In 190 Ukrainian patients, the integrase gene sequence was also determined. The most reported route of transmission was heterosexual contact, followed by intravenous drug use, and men having sex with men (MSM). Several pre-existing drug resistance mutations were found against non-nucleoside reverse transcriptase inhibitors (RTIs) (n = 103), protease inhibitors (n = 11), and nucleoside analogue RTIs (n = 12), mostly polymorphic mutations or revertants. In the integrase gene, four strains with accessory integrase strand transfer inhibitor mutations were identified. Sub-subtype A6 caused most of the infections (713/812; 87.8%) in all three countries, including in MSM. In contrast to earlier studies, no clear clusters related to the route of transmission were identified, indicating that, within the region, the exchange of viruses among the different risk groups may occur more often than earlier reported.

Background factors in people living with HIV in Japan who switch to cabotegravir plus rilpivirine: A pilot study

Long-acting therapy of cabotegravir and rilpivirine is expected to free people from the negative emotions of living with HIV associated with taking drugs, but problems such as increased number of hospital visits, lack of anti-HBV activity, and limited convenience in people with concomitant drugs have been noted. In this single-center, prospective, cross-sectional study, we investigated background factors of people living with HIV in Japan who chose cabotegravir plus rilpivirine. Forty-seven percent (36 of 76) of individuals chose this regimen, but many people living with HIV who visited the hospital once every 3 months or needed concomitant medications due to complications chose this regimen and there were no significant differences in background factors that could affect convenience between the groups of those who switched and those who did not.

Perspectives of people living with HIV-1 on implementation of long-acting cabotegravir plus rilpivirine in US healthcare settings: results from the CUSTOMIZE hybrid III implementation-effectiveness study

INTRODUCTION

The CUSTOMIZE hybrid III implementation-effectiveness study evaluated implementation of once-monthly long-acting (LA) cabotegravir + rilpivirine in diverse US healthcare settings. Here, we report patient participant perspectives after 12 months in CUSTOMIZE.

METHODS

CUSTOMIZE was a phase IIIb, 12-month study conducted from July 2019 to October 2020 at eight diverse US HIV clinics that enrolled virologically suppressed people living with HIV-1 (PLHIV) on a stable oral regimen to receive monthly cabotegravir + rilpivirine LA injections after a 1-month oral lead-in. Participants were administered quantitative surveys before injections at months 1 (baseline), 4 and 12. A randomly selected subset of participants was interviewed at baseline and month 12. Data collection at month 12 was completed by October 2020 (during the COVID-19 pandemic).

RESULTS

At baseline, 109 and 34 participants completed surveys and interviews, respectively; 87% were male; 35% were Black or African American. All participants who remained in the study at month 12 (n = 102) maintained HIV-1 RNA <50 copies/ml; two participants withdrew due to injection-related reasons. Mean total scores measuring acceptability and appropriateness of cabotegravir + rilpivirine LA were high at baseline (4.5-4.6 out of 5) and month 12 (4.7-4.9). At month 12, 74% of participants reported nothing interfered with receiving LA injections; injection pain or soreness was the most common concern (15%). Time spent in the clinic and coming to the clinic for monthly injections was very or extremely acceptable after 12 months for most participants (93% and 87%, respectively), with 64% reporting having spent ≤30 minutes in the clinic for injection visits. At month 12, 92% of participants preferred LA injections to daily oral tablets (3%); 97% plan to continue LA treatment going forward. In month 12 interviews, 24 (77%) of 31 participants reported the COVID-19 pandemic did not impact their ability to receive treatment.

CONCLUSIONS

Once-monthly cabotegravir + rilpivirine LA was highly acceptable among PLHIV who were virologically suppressed on a stable antiretroviral regimen and interested in trying LA therapy, with few participants reporting challenges receiving LA injections. Implementation data from CUSTOMIZE suggest that monthly LA injections provide a convenient and appealing treatment option for PLHIV.

Perspectives of healthcare providers on implementation of long-acting cabotegravir plus rilpivirine in US healthcare settings from a Hybrid III Implementation-effectiveness study (CUSTOMIZE)

Introduction

CUSTOMIZE evaluated the implementation of long‐acting (LA) cabotegravir + rilpivirine, a novel healthcare provider–administered injectable antiretroviral therapy regimen, in diverse US healthcare settings. Findings from staff‐study participants (SSPs) through 12 months of implementation are reported.

Methods

CUSTOMIZE was a phase IIIb, 12‐month, single‐arm, hybrid III implementation‐effectiveness study conducted from July 2019 to October 2020 at eight US clinics of five clinic types: private practice (n = 2), federally qualified health centre (n = 2), university (n = 2), AIDS Healthcare Foundation (n = 2) and health maintenance organization (n = 1). Eligible patient participants received monthly cabotegravir + rilpivirine LA injections after a 1‐month oral lead‐in. At baseline, month 4 and month 12, SSPs (n = 3 each per clinic), including physicians, nurses or injectors, and administrators, completed quantitative surveys and semi‐structured interviews to assess implementation outcomes (acceptability, appropriateness and feasibility of intervention measures), programme sustainability and SSP perceptions of, attitudes towards, and expectations for cabotegravir + rilpivirine LA. Month 12 data collection occurred during the COVID‐19 pandemic.

Results

In surveys, SSPs reported high mean total scores for acceptability, appropriateness and feasibility of cabotegravir + rilpivirine LA implementation at baseline (4.43, 4.52 and 4.38 of 5, respectively) and month 12 (4.45, 4.61 and 4.46 of 5, respectively), regardless of clinic type. At month 12, SSPs were positive about the implementation sustainability (mean Program Sustainability Assessment Tool score, 5.83 out of 7). At baseline, SSPs’ top concern was patients’ ability to maintain monthly appointments (81%); at month 12, 39% had this concern. The proportion of SSPs reporting patient injection pain or soreness as a barrier was consistent at month 12 versus baseline (48% vs. 46%). Most (78%) SSPs reported optimal implementation of cabotegravir + rilpivirine LA in their clinics was achieved in 1–3 months. In interviews, SSP‐reported strategies for successful implementation included teamwork, using a web‐based treatment planner and having a designated person to track appointment scheduling. In month 12 interviews, SSP‐reported structural changes needed for implementation included changing clinic hours and purchasing refrigerators.

Conclusions

In CUSTOMIZE, cabotegravir + rilpivirine LA was successfully implemented across a range of US healthcare settings. Barriers were mitigated with minor process adjustments.

The future of long-acting cabotegravir plus rilpivirine therapy: Deeds and misconceptions

HIV infection is currently managed as a chronic disease thanks to the improvement of antiretroviral therapy (ART). In this light, treatment is lifelong. Therefore, switch to new regimens is a natural event during long-term therapies to avoid problems related to toxicity, adherence, failure and potential selection of drug resistance. In this context, coformulations of multiple agents in one pill and the development of novel drug classes and drugs with high genetic barrier to resistance are now available. The recent approval of the long-acting once monthly or bimonthly injectable combination of the second-generation strand transfer integrase inhibitor (InSTI) cabotegravir (CAB) together with the non-nucleoside reverse transcriptase inhibitor (NNRTI) rilpivirine (RPV) represents the most recent achievement along the line of potent and convenient ART. Several pivotal trials (such as LATTE-2, ATLAS, FLAIR, and ATLAS-2M) largely demonstrated the high efficacy and safety of this long-acting formulation used as an induction-maintenance strategy. Few confirmed virological failures (CVF) have been observed. The combination of at least two baseline factors among HIV-1 subtype A6/A1, a body mass index ≥30 kg/m², and RPV resistance associated mutations, was associated with an increased risk of CVF at week 48. Available data indicate that this long-acting therapeutic strategy is attractive and potent, thus defining the most appropriate patient and how to handle practical issues is warranted.

Cabenuva: the last FDA-approved drug to treat HIV

INTRODUCTION

The conventional combination antiretroviral therapy (cART) besides all its benefits, exhibited poor adherence to daily pill administration, life-long treatment period and emergence of viral resistance. The development of long-acting (LA) drugs have changed the management of common medical conditions for human immunodeficiency virus (HIV). Cabenuva is the first LA antiretroviral injectable drug composed of nano-formulation of cabotegravir (CAB) and rilpivirine (RPV).

AREAS COVERED

In this review article, we aim to have a brief overview of results of major clinical trials which administrated cabenuva for patients considering the efficacy and safety profiles. Moreover, we discuss about CAB and RPV chemical structure, mechanism of action, ‎activity against drug-sensitive and resistant HIV and pharmacodynamics/ pharmacokinetics properties.

EXPERT OPINION

Based on the results of the ATLAS and FLAIR trials, cabenuva regimen once-monthly has shown equal effectivity to oral cART in maintaining HIV-1 suppression in patients. Furthermore, ATLAS-2M study revealed the non-inferiority of cabenuva regimen every 8 weeks compared to every 4 weeks. The injectable LA ART, reduces the number of treatment intake as well as increases adherence especially in patients with HIV-related stigma. Administration of extended-release agents probably minimize the risk of treatment-related toxicity and resistance related to sub-optimal adherence to oral ART, so cabenuva can be suggested as a suitable alternative for HIV infection control in current era.