Use of integrase inhibitors in HIV-associated tuberculosis in high-burden settings: implementation challenges and research gaps

Treatment Responses to Integrase Strand-transfer Inhibitor-containing Antiretroviral Regimens in Combination With Short-course Rifapentine-based Regimens for Latent Tuberculosis Infection Among People With HIV

BACKGROUND

Real-world experience with combinations of short-course rifapentine-based regimens and integrase strand-transfer inhibitor-containing antiretroviral therapy (ART) in management of latent tuberculous infection (LTBI) is limited among people with human immunodeficiency virus (PWH).

METHODS

From August 2019 to October 2022, PWH receiving 3 months of weekly rifapentine plus isoniazid (3HP) or 1 month of daily rifapentine plus isoniazid (1HP) in combination with ART were included. The primary outcome was virologic response within 12 months after LTBI treatment; secondary outcomes included treatment completion rate and safety of LTBI regimens.

RESULTS

During the study period, 479 PWH (94.6% male; median age, 43 years) were included: 142 received 1HP and bictegravir (BIC)-containing regimens (1HP/BIC group), 46 1HP and dolutegravir (DTG)-containing regimens (1HP/DTG group), 38 3HP and BIC-containing regimens (3HP/BIC group), 214 3HP and DTG-containing regimens (3HP/DTG group), 17 1HP and other ART regimens (1HP/others group), and 22 3HP/other ART regimens (3HP/others group). In the intention-to-treat analysis, the proportions of PWH maintaining plasma HIV-1 RNA <200 copies/mL within 12 months after LTBI treatment completion were 96.5% (1HP/BIC), 100% (1HP/DTG), 100% (3HP/BIC), 95.8% (3HP/DTG), 100% (1HP/others), and 100% (3HP/others). The overall completion rates were >80% for all treatment groups, whereas >50% of the included PWH experienced any adverse event. LTBI regimens and ART combinations were not associated with virologic response and completion rate.

CONCLUSIONS

Combinations of short-course rifapentine-based regimens and integrase strand-transfer inhibitor-containing ART maintained viral suppression for most PWH within 12 months of LTBI treatment completion with low rates of grade 3 or higher adverse events.

HIV-1 drug resistance in people on dolutegravir-based antiretroviral therapy: a collaborative cohort analysis

BACKGROUND

The widespread use of the integrase strand transfer inhibitor (INSTI) dolutegravir in first-line and second-line antiretroviral therapy (ART) might facilitate emerging resistance. The DTG RESIST study combined data from HIV cohorts to examine patterns of drug resistance mutations (DRMs) and identify risk factors for dolutegravir resistance.

METHODS

We included cohorts with INSTI resistance data from two collaborations (ART Cohort Collaboration, International epidemiology Databases to Evaluate AIDS in Southern Africa), and the UK Collaborative HIV Cohort. Eight cohorts from Canada, France, Germany, Italy, the Netherlands, Switzerland, South Africa, and the UK contributed data on individuals who were viraemic on dolutegravir-based ART and underwent genotypic resistance testing. Individuals with unknown dolutegravir initiation date were excluded. Resistance levels were categorised using the Stanford algorithm. We identified risk factors for resistance using mixed-effects ordinal logistic regression models.

FINDINGS

We included 599 people with genotypic resistance testing on dolutegravir-based ART between May 22, 2013, and Dec 20, 2021. Most had HIV-1 subtype B (n=351, 59%), a third had been exposed to first-generation INSTIs (n=193, 32%), 70 (12%) were on dolutegravir dual therapy, and 18 (3%) were on dolutegravir monotherapy. INSTI DRMs were detected in 86 (14%) individuals; 20 (3%) had more than one mutation. Most (n=563, 94%) were susceptible to dolutegravir, seven (1%) had potential low, six (1%) low, 17 (3%) intermediate, and six (1%) high-level dolutegravir resistance. The risk of dolutegravir resistance was higher on dolutegravir monotherapy (adjusted odds ratio [aOR] 34·1, 95% CI 9·93-117) and dolutegravir plus lamivudine dual therapy (aOR 9·21, 2·20-38·6) compared with combination ART, and in the presence of potential low or low (aOR 5·23, 1·32-20·7) or intermediate or high-level (aOR 13·4, 4·55-39·7) nucleoside reverse transcriptase inhibitor (NRTI) resistance.

INTERPRETATION

Among people with viraemia on dolutegravir-based ART, INSTI DRMs and dolutegravir resistance were rare. NRTI resistance substantially increased the risk of dolutegravir resistance, which is of concern, notably in resource-limited settings. Monitoring is important to prevent resistance at the individual and population level and ensure the long-term sustainability of ART.

FUNDING

US National Institutes of Health, Swiss National Science Foundation.

Clinical Relevance of Drug Interactions in People Living with Human Immunodeficiency Virus on Antiretroviral Therapy-Update 2022: Systematic Review

BACKGROUND

The clinical outcomes of antiretroviral drugs may be modified through drug interactions; thus, it is important to update the drug interactions in people living with HIV (PLHIV).

AIM

To update clinically relevant drug interactions in PLHIV on antiretroviral therapy with novel drug interactions published from 2017 to 2022.

METHODS

A systematic review in Medline/PubMed database from July 2017 to December 2022 using the Mesh terms antiretroviral agents and drug interactions or herb-drug interactions or food-drug interactions. Publications with drug interactions in humans, in English or Spanish, and with full-text access were retrieved. The clinical relevance of drug interactions was grouped into five levels according to the gravity and probability of occurrence.

RESULTS

A total of 366 articles were identified, with 219 (including 87 citation lists) were included, which allowed for the identification of 471 drug interaction pairs; among them, 291 were systematically reported for the first time. In total 42 (14.4%) and 137 (47.1%) were level one and two, respectively, and 233 (80.1%) pairs were explained with the pharmacokinetic mechanism. Among these 291 pairs, protease inhibitors (PIs) and ritonavir/cobicistat-boosted PIs, as well as integrase strand transfer inhibitors (InSTIs), with 70 (24.1%) and 65 (22.3%) drug interaction pairs of levels one and two, respectively, were more frequent.

CONCLUSIONS

In PLHIV on antiretroviral therapy, we identify 291 drug interaction pairs systematically reported for the first time, with 179 (61.5%) being assessed as clinically relevant (levels one and two). The pharmacokinetic mechanism was the most frequently identified. PIs, ritonavir/cobicistat-boosted PIs, and InSTIs were the antiretroviral groups with the highest number of clinically relevant drug interaction pairs (levels one and two).

Impact of Obesity on the Drug-Drug Interaction Between Dolutegravir and Rifampicin or Any Other Strong Inducers

Background

Obesity is increasingly prevalent among people with HIV. Obesity can impact drug pharmacokinetics and consequently the magnitude of drug-drug interactions (DDIs) and, thus, the related recommendations for dose adjustment. Virtual clinical DDI studies were conducted using physiologically based pharmacokinetic (PBPK) modeling to compare the magnitude of the DDI between dolutegravir and rifampicin in nonobese, obese, and morbidly obese individuals.

Methods

Each DDI scenario included a cohort of virtual individuals (50% female) between 20 and 50 years of age. Drug models for dolutegravir and rifampicin were verified against clinical observed data. The verified models were used to simulate the concurrent administration of rifampicin (600 mg) at steady state with dolutegravir (50 mg) administered twice daily in normal-weight (BMI 18.5-30 kg/m²), obese (BMI 30-40 kg/m²), and morbidly obese (BMI 40-50 kg/m²) individuals.

Results

Rifampicin was predicted to decrease dolutegravir area under the curve (AUC) by 72% in obese and 77% in morbidly obese vs 68% in nonobese individuals; however, dolutegravir trough concentrations were reduced to a similar extent (83% and 85% vs 85%). Twice-daily dolutegravir with rifampicin resulted in trough concentrations always above the protein-adjusted 90% inhibitory concentration for all BMI groups and above the 300 ng/mL threshold in a similar proportion for all BMI groups.

Conclusions

The combined effect of obesity and induction by rifampicin was predicted to further decrease dolutegravir exposure but not the minimal concentration at the end of the dosing interval. Thus, dolutegravir 50 mg twice daily with rifampicin can be used in individuals with a high BMI up to 50 kg/m².

sHIV-1 drug resistance in people on dolutegravir-based ART: Collaborative analysis of cohort studies

Background

The widespread use of the integrase strand transfer inhibitor (INSTI) dolutegravir (DTG) in first- and second-line antiretroviral therapy (ART) may facilitate emerging resistance. We combined data from HIV cohorts to examine patterns of drug resistance mutations (DRMs) and identify risk factors for DTG resistance.

Methods

Eight cohorts from Canada, Europe, and South Africa contributed data on individuals with genotypic resistance testing on DTG-based ART. Resistance levels were categorised using the Stanford algorithm. We identified risk factors for resistance using mixed-effects ordinal logistic regression models.

Results

We included 750 people with genotypic resistance testing on DTG-based ART between 2013 and 2022. Most had HIV subtype B (N=444, 59·2%) and were treatment-experienced; 134 (17.9%) were on DTG dual and 19 (2.5%) on DTG monotherapy. INSTI DRMs were detected in 100 (13·3%) individuals; 21 (2·8%) had more than one mutation. Most (N=713, 95·1%) were susceptible to DTG, 8 (1·1%) had potential-low, 5 (0·7%) low, 18 (2·4%) intermediate and 6 (0·8%) high-level DTG resistance. The risk of DTG resistance was higher on DTG monotherapy (adjusted odds ratio (aOR) 37·25, 95% CI 11·17 to 124·2) and DTG lamivudine dual therapy (aOR 6·59, 95% CI 1·70 to 25·55) compared to combination ART, and higher in the presence of potential-low/low (aOR 4.62, 95% CI 1.24 to 17.2) or intermediate/high-level (aOR 7·01, 95% CI 2·52 to 19·48) nucleoside reverse transcriptase inhibitors (NRTI) resistance. Viral load on DTG showed a trend towards increased DTG resistance (aOR 1·42, 95% CI 0·92 to 2·19 per standard deviation of log10 area under the viral load curve).

Interpretation

Among people experiencing virological failure on DTG-based ART, INSTI DRMs were uncommon, and DTG resistance was rare. DTG monotherapy and NRTI resistance substantially increased the risk for DTG resistance, which is of concern, notably in resource-limited settings.

Real-world use and outcomes of dolutegravir-containing antiretroviral therapy in HIV and tuberculosis co-infection: a site survey and cohort study in sub-Saharan Africa

INTRODUCTION

Dolutegravir is being scaled up globally as part of antiretroviral therapy (ART), but for people with HIV and tuberculosis co-infection, its use is complicated by a drug-drug interaction with rifampicin requiring an additional daily dose of dolutegravir. This represents a disadvantage over efavirenz, which does not have a major drug-drug interaction with rifampicin. We sought to describe HIV clinic practices for prescribing concomitant dolutegravir and rifampicin, and characterize virologic outcomes among patients with tuberculosis co-infection receiving dolutegravir or efavirenz.

METHODS

Within the four sub-Saharan Africa regions of the International epidemiology Databases to Evaluate AIDS consortium, we conducted a site survey (2021) and a cohort study (2015-2021). The cohort study used routine clinical data and included patients newly initiating or already receiving dolutegravir or efavirenz at the time of tuberculosis diagnosis. Patients were followed from tuberculosis diagnosis until viral suppression (<1000 copies/ml), a competing event (switching ART regimen; loss to program/death) or administrative censoring at 12 months.

RESULTS

In the survey, 86 of 90 (96%) HIV clinics in 18 countries reported prescribing dolutegravir to patients who were receiving rifampicin as part of tuberculosis treatment, with 77 (90%) reporting that they use twice-daily dosing of dolutegravir, of which 74 (96%) reported having 50 mg tablets available to accommodate twice-daily dosing. The cohort study included 3563 patients in 11 countries, with 67% newly or recently initiating ART. Among patients receiving dolutegravir (n = 465), the cumulative incidence of viral suppression was 58.9% (95% confidence interval [CI]: 54.3-63.3%), switching ART regimen was 4.1% (95% CI: 2.6-6.2%) and loss to program/death was 23.4% (95% CI: 19.7-27.4%). Patients receiving dolutegravir had improved viral suppression compared with patients receiving efavirenz who had a tuberculosis diagnosis before site dolutegravir availability (adjusted subdistribution hazard ratio [aSHR]: 1.47, 95% CI: 1.28-1.68) and after site dolutegravir availability (aSHR 1.28, 95% CI: 1.08-1.51).

CONCLUSIONS

At a programmatic level, dolutegravir was being widely prescribed in sub-Saharan Africa for people with HIV and tuberculosis co-infection with a dose adjustment for the drug-drug interaction with rifampicin. Despite this more complex regimen, our cohort study revealed that dolutegravir did not negatively impact viral suppression.

Implementation of long-acting antiretroviral therapy in low-income and middle-income countries

PURPOSE OF REVIEW

With oral antiretroviral therapy, HIV has become a manageable chronic illness. However, UNAIDS targets for virologic suppression have not yet been attained in many low-income and middle-income countries (LMICs). Long-acting drug formulations hold promise to improve treatment outcomes. In this rapidly evolving area of research, we aim to review recent literature on the treatment of HIV with long-acting agents and identify implementation considerations for LMICs.

RECENT FINDINGS

Randomized controlled trials have shown that monthly long-acting injectable cabotegravir (CAB) and rilpivirine (RPV) is noninferior to oral ART, and 2-monthly CAB/RPV is noninferior to monthly injections. However, few people from LMICs were included. A modelling study predicts that in sub-Saharan Africa, injectable CAB/RPV is best targeted to those with poor adherence (HIV viral load >1000 copies/ml) in whom cost-effectiveness is greatest and risk of contributing to further resistance is no greater than continuation of oral ART. Other promising agents, such as lenacapavir are under investigation and may prove particularly useful in heavily treatment-experienced adults.

SUMMARY

Long-acting regimens are a promising advance in HIV treatment. By extending the dosing interval, increasing convenience and being discreet these regimens may reduce HIV treatment challenges. However, there are multiple implementation considerations in LMICs including the need for exclusion of hepatitis B, cold chain, oral bridging in case of missed dosing and switching during tuberculosis therapy. Efficacy and safety data are also awaited for settings without routine access to baseline resistance testing or regular viral load monitoring and for special populations, such as pregnancy, children and the elderly.