Outcomes of Integrase Inhibitor-based Antiretroviral Therapy in a Clinical Cohort of Treatment-experienced Children, Adolescents and Young Adults With HIV Infection

Pharmacokinetics, Safety and Antiviral Activity of Rilpivirine in Antiretroviral-naïve Children With HIV ≥6 to <12 Years Old: Week 48 and Final Analysis of Cohort 2 From the Open-label, Phase 2 PAINT Study

BACKGROUND

Rilpivirine has shown adequate antiviral activity, consistent pharmacokinetics and safety in adults and adolescents living with HIV-1. Pharmacokinetics, safety, and antiviral activity of rilpivirine were assessed in children, following at least 48 weeks of treatment.

METHODS

Cohort 2 of the open-label, phase 2 PAINT study (NCT00799864) included antiretroviral-naïve children living with HIV-1 ≥6 to <12 years old, with a viral load ≤100,000 RNA copies/mL. Participants received weight-based doses of rilpivirine in combination with a background regimen containing 2 nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs).

RESULTS

Of the 18 children enrolled, 17 completed the 48-week treatment period. Participants were mostly boys (61%), median (range) age of 9.0 years (6-11 years) and weight of 25.0 kg (17-51 kg). Most children [14/18 (78%)] were adherent (>95%) to the treatment. Pharmacokinetic exposures were similar across the recommended weight-based doses and within a range comparable to exposures seen in adult studies. At week 48, 13/18 (72%) children achieved virologic response (HIV-1 RNA <50 copies/mL, FDA Snapshot). The mean (SE) increase from baseline to week 48 in CD4+ count was 213.4 (77.80) cells/μL. Overall postbaseline, 2 participants experienced virologic failure, of which 1 carried treatment-emergent rilpivirine resistance-associated mutations (RAMs); 3 of 5 participants with suspected virologic failure carried rilpivirine and NRTI RAMs. No new safety signals were identified in this population.

CONCLUSIONS

At week 48, rilpivirine achieved adequate viral suppression in antiretroviral-naïve children ≥6 to <12 years of age. The pharmacokinetic, safety and virologic profile of rilpivirine in this age group was consistent with observations in adults and adolescents living with HIV-1.

Realizing the Promise of Dolutegravir in Effectively Treating Children and Adolescents Living With HIV in Real-world Settings in 6 Countries in Eastern and Southern Africa

BACKGROUND

Despite encouraging results from clinical trials and in high-income countries, large-scale data on the effectiveness and safety of dolutegravir (DTG) in children and adolescents living with HIV (CALHIV) are lacking in low- and middle-income countries (LMICs).

METHODS

Retrospective analysis was performed among CALHIV 0-19 years old and weighing greater than or equal to 20 kg who received DTG from 2017 to 2020 at sites in Botswana, Eswatini, Lesotho, Malawi, Tanzania and Uganda to determine effectiveness, safety and predictors of viral load suppression (VLS) among CALHIV using DTG, including through single drug substitutions (SDS).

RESULTS

Among 9419 CALHIV using DTG, 7898 had a documented post-DTG VL, and VLS post-DTG was 93.4% (7378/7898). VLS for antiretroviral therapy (ART) initiations was 92.4% (246/263), and VLS was maintained for the ART-experienced [92.9% (7026/7560) pre- vs. 93.5% (7071/7560) post-DTG; P = 0.14). Among previously unsuppressed, 79.8% (426/534) achieved VLS with DTG. Only 5 patients reported a Grade 3 or 4 adverse event (0.057 per 100 patient-years) requiring DTG discontinuation. History of protease inhibitor-based ART [odds ratio (OR) = 1.53; 95% confidence interval (CI): 1.16-2.03], care in Tanzania (OR = 5.45; 95% CI: 3.41-8.70), and being 15-19 years old (OR = 1.31; 95% CI: 1.03-1.65) were associated with gain of VLS post-DTG. Predictors of VLS on DTG included VLS before DTG (OR = 3.87; 95% CI: 3.03-4.95) and using the once-daily, single tab tenofovir-lamivudine-DTG regimen (OR = 1.78; 95% CI: 1.43-2.22). SDS maintained VLS [95.9% (2032/2120) pre- vs. 95.0% (2014/2120) post-SDS with DTG; P = 0.19], and 83.0% (73/88) of unsuppressed gained VLS using SDS with DTG.

CONCLUSIONS

We found DTG to be highly effective and safe within our cohort of CALHIV in LMICs. These findings can empower clinicians to prescribe DTG confidently to eligible CALHIV.

A clinical review of HIV integrase strand transfer inhibitors (INSTIs) for the prevention and treatment of HIV-1 infection

Integrase strand transfer inhibitors (INSTIs) have improved the treatment of human immunodeficiency virus (HIV). There are currently four approved for use in treatment-naïve individuals living with HIV; these include first generation raltegravir, elvitegravir, and second generation dolutegravir and bictegravir. The most recent INSTI, cabotegravir, is approved for (1) treatment of HIV infection in adults to replace current antiretroviral therapy in individuals who maintain virologic suppression on a stable antiretroviral regimen without history of treatment failure and no known resistance to its components and (2) pre-exposure prophylaxis in individuals at risk of acquiring HIV-1 infection. Cabotegravir can be administered intramuscularly as a monthly or bi-monthly injection depending on the indication. This long-acting combination has been associated with treatment satisfaction in clinical studies and may be helpful for individuals who have difficulty taking daily oral medications. Worldwide, second generation INSTIs are preferred for treatment-naïve individuals. Advantages of these INSTIs include their high genetic barrier to resistance, limited drug-drug interactions, excellent rates of virologic suppression, and favorable tolerability. Few INSTI resistance-associated mutations have been reported in clinical trials involving dolutegravir, bictegravir and cabotegravir. Other advantages of specific INSTIs include their use in various populations such as infants and children, acute HIV infection, and individuals of childbearing potential. The most common adverse events observed in clinical studies involving INSTIs included diarrhea, nausea, insomnia, fatigue, and headache, with very low rates of treatment discontinuation versus comparator groups. The long-term clinical implications of weight gain associated with second generation INSTIs dolutegravir and bictegravir warrants further study. This review summarizes key clinical considerations of INSTIs in terms of clinical pharmacology, drug-drug interactions, resistance, and provides perspective on clinical decision-making. Additionally, we summarize major clinical trials evaluating the efficacy and safety of INSTIs in treatment-naïve patients living with HIV as well as individuals at risk of acquiring HIV infection.

Adherence, Effectiveness and Safety of Dolutegravir Based Antiretroviral Regimens among HIV Infected Children and Adolescents in Tanzania

Objectives:This study aimed at assessing adherence, effectiveness, and safety of DTG-based HAART regimens among HIV-infected children and adolescents in Tanzania. Methods: This was a single-center prospective cohort study, conducted at the pediatric HIV Clinic in Mbeya, Tanzania. A binary logistic regression model was used to determine predictors of undetectable viral load at week 24. The results were significant when P-value was <0.05. Results: A total of 200 patients were enrolled with the majority (85.5%) being treatment experienced. High adherence levels (71%) were observed using the pharmacy refill method. At week 24, the overall proportion of patients with undetectable viral load was 70.2%. The predictors of undetectable viral load were age, World Health Organization (WHO) clinical stage, baseline VL and adherence to pharmacy refill. Conclusion: The majority of patients attained undetectable viral load 6 months after using DTG based regimen. DTG-based regimens were generally safe with few ADEs reported.

Dolutegravir in the long term in children and adolescents: frequent virological failure but rare acquired genotypic resistance

OBJECTIVES

Although widely recommended, data about dolutegravir efficacy in HIV-1-infected children/adolescents are scarce, limited to short-term follow-up and mainly extrapolated from studies in adults with good adherence to treatment. This study aimed to provide long-term data about the risk of virological failure (VF) and acquired genotypic resistance in children and adolescents receiving dolutegravir.

METHODS

This retrospective monocentric study included 134 paediatric patients who received a dolutegravir-based regimen for ≥ 12 months in 2014-2020. Virological failure was defined as not achieving a plasma viral load (pVL) < 50 copies/mL within 3 months of dolutegravir initiation or as experiencing virological rebound ≥ 50 copies/mL.

RESULTS

Most of the subjects were antiretroviral therapy-experienced (90.3%), naïve from integrase inhibitors (90.3%) and displayed virological suppression at baseline (63.4%). Their median (interquartile range, IQR) age was 12.0 (8.0-15.8) years. Genotypic susceptibility score of the new regimen was ≥ 2 in 96% of cases. Median (IQR) follow-up was 34 (22-50) months. Virological failure occurred in 43 people (32.1%), more frequently where the baseline pVL was ≥ 50 copies/mL (67.4% vs. 22.0%, P < 0.01). M184V/I mutations in the reverse transcriptase gene were newly detected in three people with VF. Resistance to dolutegravir (mutations G118R and E138A in the integrase gene) emerged in one adolescent (0.7% of subjects, 2.3% of those with VF).

CONCLUSIONS

Whereas VF is relatively common on dolutegravir in the paediatric population, regimens associating dolutegravir with more than one fully active drug were associated with a low rate of emergent drug resistance. This result strengthens the recommendation of dolutegravir as part of preferred combinations in children/adolescents.