Weekends-off efavirenz-based antiretroviral therapy in HIV-infected children, adolescents and young adults (BREATHER): Extended follow-up results of a randomised, open-label, non-inferiority trial

D3/Penta 21 clinical trial design: A randomised non-inferiority trial with nested drug licensing substudy to assess dolutegravir and lamivudine fixed dose formulations for the maintenance of virological suppression in children with HIV-1 infection, aged 2 to 15 years

BACKGROUND

There is increasing interest in utilising two-drug regimens for HIV treatment with the goal of reducing toxicity and improve acceptability. The D3 trial evaluates the efficacy and safety of DTG/3TC in children and adolescents and includes a nested pharmacokinetics(PK) substudy for paediatric drug licensing.

METHODS

D3 is an ongoing open-label, phase III, 96-week non-inferiority randomised controlled trial(RCT) conducted in South Africa, Spain, Thailand, Uganda and the United Kingdom. D3 has enrolled 386 children aged 2- < 15 years, virologically suppressed for ≥6 months, with no prior treatment failure. Participants were randomised 1:1 to receive DTG/3TC or DTG plus two nucleoside reverse transcriptase inhibitors(NRTIs), stratified by region, age (2- < 6, 6- < 12, 12- < 15 years) and DTG use at enrolment (participants permitted to start DTG at enrolment). The primary outcome is confirmed HIV-1 RNA viral rebound ≥50 copies/mL by 96-weeks. The trial employs the Smooth Away From Expected(SAFE) non-inferiority frontier, which specifies the non-inferiority margin and significance level based on the observed event risk in the control arm. The nested PK substudy evaluates WHO weight-band-aligned dosing in the DTG/3TC arm.

DISCUSSION

D3 is the first comparative trial evaluating DTG/3TC in children and adolescents. Implications of integrating a PK substudy and supplying data for prompt regulatory submission, were carefully considered to ensure the integrity of the ongoing trial. The trial uses an innovative non-inferiority frontier for the primary analysis to allow for a lower-than-expected confirmed viral rebound risk in the control arm, while ensuring interpretability of results and maintaining the planned sample size in an already funded trial.

TRIAL REGISTRATION

International Standard Randomised Clinical Trial Number Register: ISRCTN17157458. European Clinical Trials Database: 2020-001426-57.

CLINICALTRIALS

gov: NCT04337450.

In Silico Pharmacokinetics Evaluation of Forgiveness for Doravirine and Rilpivirine

BACKGROUND

This study aimed to evaluate the concentrations of rilpivirine (RLP) and doravirine (DOR) after 3 days-off using simulations from population pharmacokinetics models.

METHODS

The authors conducted a series of 500 sets of 10,000 Monte Carlo simulations to examine the steady-state conditions for 2 common dosage levels: 25 mg/d for RLP and 100 mg/d for DOR. These simulations were conducted under 2 scenarios: 1 without drug cessation and another after a 3-day break. The validity of the implementation was established through a comparison of median trough concentrations (C24h) with previously reported data. Subsequently, the proportion of simulated patients with C24h and C72h after 3 days-off (C72h/3do) that exceeded the inhibitory concentration 50 (IC50), 5.2 mcg/L for DOR and 20.5 mcg/L for RLP respectively, was calculated. The inhibitory quotient (IQ) was also computed, which was 6 times IC50 for DOR and 4.5 times IC50 for RLP. Finally, nomograms were constructed to estimate the probability of having C72h/3do > IC50 or > IQ for different ranges of C24h.

RESULTS

Simulated C24h median ± SD for RLP were 61.8 ± 0.4 mcg/L and for DOR 397 ± 0 mcg/L. For RLP, 99.3 ± 0.1% exceeded IC50 at C24h, 16.4 ± 0.4% at C72h/3do, and none surpassed the IQ threshold. In contrast, DOR had 100% ± 0% above IC50 at C24h, 93.6 ± 0.2% at C72h/3do, and 58.6 ± 0.5% exceeded the IQ.

CONCLUSIONS

These findings suggest that treatment with DOR may offer a more forgiving therapeutic profile than RLP, given the larger proportion of patients achieving effective drug exposure with DOR. However, it is important to acknowledge a significant limitation of this study, namely, the assumption that drug concentration is a perfect surrogate for drug effectiveness.

Projected Life Expectancy for Adolescents With HIV in the US

Importance

Life expectancy is a key measure of overall population health. Life expectancy estimates for youth with HIV in the US are needed in the current HIV care and treatment context to guide health policies and resource allocation.

Objective

To compare life expectancy between 18-year-old youth with perinatally acquired HIV (PHIV), youth with nonperinatally acquired HIV (NPHIV), and youth without HIV.

Design, Setting, and Participants

Using a US-focused adolescent-specific Monte Carlo state-transition HIV model, we simulated individuals from age 18 years until death. We estimated probabilities of HIV treatment and care engagement, HIV progression, clinical events, and mortality from observational cohorts and clinical trials for model input parameters. The simulated individuals were 18-year-old race and ethnicity-matched youth with PHIV, youth with NPHIV, and youth without HIV; 47%, 85%, and 50% were assigned male sex at birth, respectively. Individuals were categorized by US Centers for Disease Control and Prevention-defined HIV acquisition risk: men who have sex with men, people who ever injected drugs, heterosexually active individuals at increased risk for HIV infection, or average risk for HIV infection. Distributions were 3%, 2%, 12%, and 83% for youth with PHIV and youth without HIV, and 80%, 6%, 14%, and 0% for youth with NPHIV, respectively. Among the simulated youth in this analysis, individuals were 61% Black, 24% Hispanic, and 15% White, respectively.

Exposures

HIV status by timing of acquisition.

Main Outcomes

Life expectancy loss for youth with PHIV and youth with NPHIV: difference between mean projected life expectancy under current and ideal HIV care scenarios compared with youth without HIV. Uncertainty intervals reflect varying adolescent HIV-related mortality inputs (95% CIs).

Results

Compared with youth without HIV (life expectancy: male, 76.3 years; female, 81.7 years), male youth with PHIV and youth with NPHIV had projected life expectancy losses of 10.4 years (95% CI, 5.5-18.1) and 15.0 years (95% CI, 9.3-26.8); female youth with PHIV and youth with NPHIV had projected life expectancy losses of 11.8 years (95% CI, 6.4-20.2) and 19.5 years (95% CI, 13.8-31.6), respectively. When receiving ideal HIV care, life expectancy losses were projected to improve for youth with PHIV (male: 0.5 years [95% CI, 0.3-1.8]: female: 0.6 years [95% CI, 0.4-2.1]) but were projected to persist for youth with NPHIV (male: 6.0 years [95% CI, 5.0-9.1]; female: 10.4 years [95% CI, 9.4-13.6]).

Conclusions

This adolescent-focused microsimulation modeling analysis projected that youth with HIV would have shorter life expectancy than youth without HIV. Projected differences were larger for youth with NPHIV compared with youth with PHIV. Differences in mortality by sex at birth, sexual behavior, and injection drug use contributed to lower projected life expectancy among youth with NPHIV. Interventions focused on HIV care and social factors are needed to improve life expectancy for youth with HIV in the US.

The Smooth Away From Expected (SAFE) non-inferiority frontier: theory and implementation with an application to the D3 trial

BACKGROUND

In a non-inferiority trial, the choice of margin depends on the expected control event risk. If the true risk differs from expected, power and interpretability of results can be affected. A non-inferiority frontier pre-specifies an appropriate non-inferiority margin for each value of control event risk. D3 is a non-inferiority trial comparing two treatment regimens in children living with HIV, designed assuming a control event risk of 12%, a non-inferiority margin of 10%, 80% power and a significance level (α) of 0.025. We consider approaches to choosing and implementing a frontier for this already funded trial, where changing the sample size substantially would be difficult.

METHODS

In D3, we fix the non-inferiority margin at 10%, 8% and 5% for control event risks of ≥9%, 5% and 1%, respectively. We propose four frontiers which fit these fixed points, including a Smooth Away From Expected (SAFE) frontier. Analysis approaches considered are as follows: using the pre-specified significance level (α=0.025); always using a reduced significance level (to achieve α≤0.025 across control event risks); reducing significance levels only when the control event risk differs significantly from expected (control event risk <9%); and using a likelihood ratio test. We compare power and type 1 error for SAFE with other frontiers.

RESULTS

Changing the significance level only when the control event risk is <9% achieves approximately nominal (<3%) type I error rate and maintains reasonable power for control event risks between 1 and 15%. The likelihood ratio test method performs similarly, but the results are more complex to present. Other analysis methods lead to either inflated type 1 error or badly reduced power. The SAFE frontier gives more interpretable results with low control event risks than other frontiers (i.e. it uses more reasonable non-inferiority margins). Other frontiers do not achieve power close (i.e. within 1%) to SAFE across the range of likely control event risks while controlling type I error.

CONCLUSIONS

The SAFE non-inferiority frontier will be used in D3, and the non-inferiority margin and significance level will be modified if the control event risk is lower than expected. This ensures results will remain interpretable if design assumptions are incorrect, while achieving similar power. A similar approach could be considered for other non-inferiority trials where the control event risk is uncertain.

Interventions to Improve Adolescent HIV Care Outcomes

PURPOSE OF REVIEW

This review of recent studies evaluating interventions to improve HIV care outcomes among adolescents with HIV (AHIV) was conducted to provide a comprehensive overview of the recent evidence, highlight promising approaches, and suggest directions for future research.

RECENT FINDINGS

Our scoping review revealed 65 studies evaluating a variety of interventions and using a range of study designs at various stages of research. Effective approaches included community-based, integrated service delivery models with case management, trained community adolescent treatment supporters, and consideration of social determinants of health. Recent evidence also supports the feasibility, acceptability, and preliminary efficacy of other innovative approaches, including mental health interventions as well as technology-delivered approaches; however, more research is needed to build the evidence base for these interventions. Our review's findings suggest that interventions providing comprehensive, individualized support are essential to improving HIV care outcomes among adolescents. More research is needed to build the evidence base for such interventions and ensure effective, equitable implementation to support the global target of ending the AIDS epidemic by 2030.

Intermittent Bictegravir/Emtricitabine/Tenofovir Alafenamide Treatment Maintains High Level of Viral Suppression in Virally Suppressed People Living with HIV

In this observational study, we aimed to evaluate whether bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) administered 5 or 4 days a week is able to maintain viral suppression in people living with HIV (PLHIV). We enrolled 85 patients who initiated intermittent B/F/TAF between 28 November 2018 and 30 July 2020: median (IQR) age 52 years (46–59), duration of virological suppression 9 years (3–13), CD4 633/mm3 (461–781). Median follow-up was 101 weeks (82–111). The virological success rate (no virological failure [VF]: confirmed plasma viral load [pVL] ≥ 50 copies/mL, or single pVL ≥ 200 copies/mL, or ≥50 copies/mL with ART change) was 100% (95%CI 95.8–100) and the strategy success rate (pVL < 50 copies/mL with no ART regimen change) was 92.9% (95%CI 85.3–97.4) at W48. Two VF occurred at W49 and W70, in 2 patients self-reporting poor compliance. No resistance mutation emerged at time of VF. Eight patients presented strategy discontinuation for adverse events. There was no significant change in the CD4 count, residual viraemia rate, neither body weight during follow-up, but a slight increase in CD4/CD8 ratio (p = 0.02). In conclusion, our findings suggest that B/F/TAF administered 5 or 4 days a week could maintain the control of HIV replication in virologically suppressed PLHIV while reducing cumulative exposition of ART.

Children living with HIV: a narrative review of recent advances in pediatric HIV research and their implications for clinical practice

Despite the great strides that have been made in prevention of mother to child transmission (PMTCT), children continue to acquire HIV. The reduction in transmission is variable, for example in Africa, great gains have been made in Eastern and Southern Africa, but critical gaps remain in West and Central Africa. These gaps are also observed in the treatment of children living with HIV. Although there is increased access to lifesaving antiretroviral therapy (ART), management of pediatric HIV infection continues to be a challenge to clinicians in low-income countries where the disease burden is disproportionately high. On the contrary, recent advances in ART drug types and formulations provide great hope. In this narrative review, we present key updates in HIV care and promising ART research among children and adolescents living with HIV. We particularly highlight the dolutegravir (DTG) research which informed the change of the World Health Organization (WHO) ART guidelines in this age group. Significant gaps remain around management of children presenting with advanced disease to minimize mortality and in the long-term care and treatment of adolescents living with HIV. Research to address these sensitive areas is crucial for the realization of global, regional, and national pediatric HIV targets.

Factors Associated with Transition of HIV Care Readiness Among Adolescents and Youth from a Specialty Pediatric HIV Clinic in the United States

Transitioning from pediatric to adult services is known to be associated with worsening of health outcomes and decreased retention in care among adolescents and youth living with HIV (AYLHIV). We aimed to identify factors associated with HIV care transition readiness among AYLHIV in care at a pediatric HIV clinic in Washington, DC. This retrospective cohort study from June 2019 through January 2021 collected demographic and clinical characteristics from the clinic database. We adapted the Transition Readiness Assessment Questionnaire (TRAQ; scored 1-4; 1 being the lowest level of preparedness) to evaluate transition readiness over time. We analyzed data using two-sided unadjusted two-sample and paired t-tests and adjusted analysis of variance (ANOVA). We included 103 AYLHIV (50.49% female; 100% non-Hispanic Black/African American; mean age = 19.54 ± 2.78 years; 81.55% virally suppressed). Mean baseline TRAQ score (2.32 ± 0.78) was associated with age (p < 0.0001), gender (p = 0.033), mode of HIV transmission (p = 0.0005), viral suppression (p = 0.0033), and duration of HIV diagnosis (p = 0.012). AYLHIV diagnosed with HIV within the prior year experienced significantly greater mean improvement in transition readiness compared with those living with HIV for >10 years (p = 0.013). Adjusted for covariates, older age (p < 0.0001), undetectable viral load (p = 0.0008), and presence of mental health condition(s) (p = 0.020) were associated with higher TRAQ scores. Lower improvement in transition readiness among youth with a longer history of HIV suggests that AYLHIV with perinatally acquired HIV might require additional support than those with horizontally acquired HIV.

Short-cycle therapy in HIV-infected adults: rilpivirine combination 4 days on/3 days off therapy

BACKGROUND

Short-cycle therapy (SCT) is the administration of ART for 4 or 5 consecutive days a week, followed by 3 or 2 days off therapy. Its benefits include improving patient satisfaction and reducing ART toxicity and costs.

METHODS

In this observational study we included HIV-infected adults with a three-drug ART containing rilpivirine, a history of long-term virological suppression and no evidence of resistance to previous drug regimens. Patients switched to a SCT of 4 days on/3 days off and were followed for 48 weeks with regular check-ups. The primary outcome was virological suppression; secondary outcomes were changes in CD4+ cells and rilpivirine plasma concentration, the occurrence of adverse events and resistance in the case of failure, and patient satisfaction.

RESULTS

At week 48 no virological failure was observed, with a virological suppression rate of 30/30 (100%). Three patients switched back to continuous therapy for other reasons, with an overall success rate of SCT of 30/33 (90.9%, 95% CI = 81.24% to 100%). The CD4+ mean value increased by +64 cells/mm3 (95% CI = -59 to +187 cells/mm3; P = 0.052). No adverse events were observed and the mean total score in the satisfaction questionnaire was 57.7/60 (96.22%). Rilpivirine plasma concentration was below the efficacy threshold in 71.3% of the samples, suggesting that the patients' characteristics, more than the drug's pharmacokinetics, played a role in maintaining virological suppression.

CONCLUSIONS

SCT with rilpivirine-containing regimens could be an effective alternative to continuous therapy in selected HIV-infected patients with previous long-term virological suppression.

Plasticity of the Immune System in Children Following Treatment Interruption in HIV-1 Infection

It is intriguing that, unlike adults with HIV-1, children with HIV-1 reach a greater CD4+ T cell recovery following planned treatment cessation. The reasons for the better outcomes in children remain unknown but may be related to increased thymic output and diversity of T cell receptor repertoires. HIV-1 infected children from the PENTA 11 trial tolerated planned treatment interruption without adverse long-term clinical, virological, or immunological consequences, once antiretroviral therapy was re-introduced. This contrasts to treatment interruption trials of HIV-1 infected adults, who had rapid changes in T cells and slow recovery when antiretroviral therapy was restarted. How children can develop such effective immune responses to planned treatment interruption may be critical for future studies. PENTA 11 was a randomized, phase II trial of planned treatment interruptions in HIV-1-infected children (ISRCTN 36694210). In this sub-study, eight patients in long-term follow-up were chosen with CD4+ count>500/ml, viral load <50c/ml at baseline: four patients on treatment interruption and four on continuous treatment. Together with measurements of thymic output, we used high-throughput next generation sequencing and bioinformatics to systematically organize memory CD8+ and naïve CD4+ T cell receptors according to diversity, clonal expansions, sequence sharing, antigen specificity, and T cell receptor similarities following treatment interruption compared to continuous treatment. We observed an increase in thymic output following treatment interruption compared to continuous treatment. This was accompanied by an increase in T cell receptor clonal expansions, increased T cell receptor sharing, and higher sequence similarities between patients, suggesting a more focused T cell receptor repertoire. The low numbers of patients included is a limitation and the data should be interpreted with caution. Nonetheless, the high levels of thymic output and the high diversity of the T cell receptor repertoire in children may be sufficient to reconstitute the T cell immune repertoire and reverse the impact of interruption of antiretroviral therapy. Importantly, the effective T cell receptor repertoires following treatment interruption may inform novel therapeutic strategies in children infected with HIV-1.

Efficacy of intermittent short cycles of integrase inhibitor-based maintenance ART in virologically suppressed HIV patients

BACKGROUND

Several studies have shown that NNRTI/PI-based triple therapy could be safely administered as a 4 days (4D) or 5 days (5D) a week maintenance strategy. We report here our experience of using an integrase inhibitor (INSTI)-based 4D/5D regimen in virologically suppressed HIV patients.

METHODS

This cohort study enrolled adult patients on ART with viral load (VL) <50 copies/mL for >1 year, who switched to an INSTI-based triple regimen given 4D/5D a week. The primary endpoint was the virological efficacy rate at Week (W) 48, with virological failure defined as confirmed VL ≥50 copies/mL.

RESULTS

A total of 73 patients were included (n = 28 for 4D, n = 45 for 5D): 54 men (74%), median (IQR) age 51 (45-57) years, ART duration 10 (6-18) years and duration of viral suppression 5 (2-9) years at baseline. As of 25 March 2019, the median follow-up was 21 (14-35) months, with a total of 161 patient-years of follow-up; all patients had reached the W24 visit, 66 (90%) W48 and 34 (47%) W96. Four patients discontinued the strategy: virological failure (n = 2) at W60 and W67, respectively, switch for renal toxicity (n = 1) at W28 and switch to rilpivirine/dolutegravir (n = 1) at W65. Overall the rate of virological success (95% CI) was 100% (94%-100%) at W24 and W48 and 93.7% (79.8%-98.2%) at W96.

CONCLUSIONS

While waiting for the final results of the large randomized QUATUOR ANRS-170 study, our real-life results suggest that the use of an intermittent maintenance triple-drug regimen given as a weekend (2 or 3 days) off is as effective with an INSTI-based regimen as with a PI or an NNRTI.

"We give them threatening advice…": expectations of adherence to antiretroviral therapy and their consequences among adolescents living with HIV in rural Malawi

INTRODUCTION

Many adolescents living with HIV in sub-Saharan Africa struggle to achieve optimal adherence to antiretroviral therapy (ART), but few studies have investigated how their treatment-taking decisions are influenced by their social interactions with providers, caregivers and community leaders. This study aims to explore the narratives that define expectations of adherence to ART among adolescents living with HIV in a rural Malawian setting.

METHODS

Overall, 45 in-depth interviews were conducted in 2016 with adolescents living with HIV, caregivers, health workers and community leaders, and four group sessions using participatory tools were undertaken with adolescents. Interviews and group sessions were audio-recorded, transcribed and translated into English. Data were coded inductively and analysed thematically.

RESULTS

Adolescents were given strict behavioural codes around optimal treatment adherence, which were often enforced through encouragement, persuasian and threats. In HIV clinics, some staff supported adolescents with broader concerns relating to living with HIV, but other measures to address sub-optimal adherence in HIV clinics were perceived by patients as punitive, including pill-counts and increased frequency of clinic visits. Community leaders felt responsible for young peoples' health, sometimes attempting to influence their treatment-taking by threatening to withdraw services, or to publically "out" those deemed to be non-adherent. At home, discussions with adolescents about HIV were often limited to dose reminders, and some caretakers resorted to physical punishment to ensure adherence. While some adolescents complied with strictly-enforced adherence rules, others demonstrated resistance by hiding missed doses, secretly throwing away drugs, or openly refusing to take them.

CONCLUSIONS

The potential of young people to adhere to their ART may be undermined by restrictive messages and punitive approaches to enforce and control their engagement with treatment at home, in the clinic and in the wider community. Interventions should focus on creating safe spaces for adolescents to speak frankly about the adherence challenges that they face and support for caregivers including home-based interventions.

State of the Mind: Growing up with HIV

Human immunodeficiency virus (HIV) is a neurotropic virus that has a detrimental impact on the developing central nervous system (CNS) of children growing up with perinatal HIV (PHIV) due to a combination of pathophysiological processes related to direct viral cytopathic effects and immune activation. This leads to a spectrum of neurocognitive impairment ranging from severe encephalopathy to subtle domain-specific cognitive impairments, as well as psychological disorders that are compounded by HIV-related stigma and sociodemographic factors that disproportionately affect PHIV children. Early commencement and consistent use of combination antiretroviral therapy (cART) has resulted in a dramatic improvement in neuropsychological outcomes for PHIV children; however, they remain vulnerable to cognitive impairment and psychological disorders, as evidenced by imaging findings, randomised clinical trials and observational studies. An optimal neuroprotective cART regimen remains elusive in children, but systemic viral suppression, regular neurocognitive and psychological screening and ready access to neuropsychological management strategies are key components for optimising neuropsychological outcomes. However, a lack of standardised and validated screening tools, particularly in resource-limited settings, hinders a precise understanding of the nature, prevalence and associations between neuropsychological symptomatology and HIV health. This article reviews the natural history, cellular pathophysiology and structural and functional imaging findings for children growing up with HIV, as well as summarising management strategies related to antiretroviral therapy, screening tools and specific interventions for neurocognitive impairments and psychological disorders.

Traversing the cascade: urgent research priorities for implementing the 'treat all' strategy for children and adolescents living with HIV in sub-Saharan Africa

Children and adolescents living with HIV (CALHIV) in sub-Saharan Africa experience significant morbidity and alarmingly high mortality rates due to critical gaps in the HIV care cascade, including late diagnosis and initiation of treatment, as well as poor retention in care and adherence to treatment. Interventions to strengthen the adult HIV care cascade may not be as effective in improving the cascade for CALHIV, for whom specific strategies are needed. Particular attention needs to be paid to the contexts of sub-Saharan Africa, where more than 85% of the world's CALHIV live. Implementing the 'treat all' strategy in sub-Saharan Africa requires dedicated efforts to address the unique diagnosis and care needs of CALHIV, in order to improve paediatric and adolescent outcomes, prevent viral resistance and reduce the number of new HIV infections. We consider the UNAIDS 90-90-90 targets from the perspective of infants, children and adolescents, and discuss the key challenges, knowledge gaps and urgent research priorities for CALHIV in implementation of the 'treat all' strategy in sub-Saharan Africa.