Efficacy and safety of dolutegravir or darunavir in combination with lamivudine plus either zidovudine or tenofovir for second-line treatment of HIV infection (NADIA): week 96 results from a prospective, multicentre, open-label, factorial, randomised, non-inferiority trial

Dolutegravir plus boosted darunavir versus recommended standard-of-care antiretroviral regimens in people with HIV-1 for whom recommended first-line non-nucleoside reverse transcriptase inhibitor therapy has failed (D2EFT): an open-label, randomised, phase 3b/4 trial

BACKGROUND

Randomised comparative data on efficacy and safety of second-line antiretroviral therapy (ART) after failure of non-nucleoside reverse transcriptase inhibitors (NNRTIs) across diverse geographical settings are scarce. The aim of this study was to evaluate optimal second-line ART for people with HIV.

METHODS

D2EFT is a completed international, randomised, open-label, phase 3b/4 trial evaluating three second-line ART strategies in adults (aged ≥18 years) with HIV-1 for whom first-line NNRTI therapy has failed. The study was done at 28 sites across 14 countries in Asia, Africa, and Latin America. It was originally designed to compare recommended standard of care (ritonavir-boosted darunavir [800 mg darunavir plus 100 mg ritonavir once daily] plus two nucleoside reverse transcriptase inhibitors [NRTIs; dosed once or twice daily]) with a novel nucleoside sparing regimen of dolutegravir (50 mg once daily) with ritonavir-boosted darunavir. The study was adapted during the first year to add a third arm of dolutegravir (50 mg once daily) with fixed tenofovir disoproxil fumarate (300 mg once daily) plus either lamivudine (300 mg once daily) or emtricitabine (200 mg once daily). Participants were randomly assigned with a computer-generated, blocked randomisation scheme (block size of two) stratified by site, previous tenofovir disoproxil fumarate use, and HIV viral load. The trial was designed to evaluate non-inferiority of either interventional arm against standard of care for the primary outcome of virological suppression, as determined by HIV RNA load of less than 50 copies per mL at 48 weeks. The prespecified non-inferiority margin was 12%. Comparisons were made with a modified intention-to-treat population, including all participants randomly assigned but excluding administrative withdrawals. This study is registered with ClinicalTrials.gov, NCT03017872.

FINDINGS

1190 individuals were screened; 828 participants were enrolled between Nov 1, 2017, and Dec 31, 2021. Two participants were unable to receive their assigned regimen for administrative reasons; and 826 participants were included in analyses. Median age was 39 years (IQR 33-46), and 450 (54%) participants were female. Baseline median CD4 count was 206 cells per μL (23-354) and median HIV RNA was 15 400 copies per mL (3600-65 986). The proportion of participants with HIV RNA of less than 50 copies per mL at 48 weeks was 194 (75%) of 257 in the ritonavir-boosted darunavir plus two NRTIs group, 222 (84%) of 264 in the ritonavir-boosted darunavir plus dolutegravir group, and 227 (78%) of 291 in the dolutegravir with tenofovir disoproxil fumarate plus either lamivudine or emtricitabine group. Compared with ritonavir-boosted darunavir plus two NRTIs, the difference in virological suppression was 8·6% (95% CI 1·7 to 15·5; p=0·016) for dolutegravir plus ritonavir-boosted darunavir and 6·7% (-1·2 to 14·4; p=0·093) for dolutegravir with tenofovir disoproxil fumarate plus either lamivudine or emtricitabine. Six deaths occurred, none of which were related to treatment. 19 pregnancies (11 livebirths) occurred with no congenital defects.

INTERPRETATION

In individuals experiencing failure of an NNRTI-based first-line ART, a switch to either dolutegravir plus ritonavir-boosted darunavir or dolutegravir with tenofovir disoproxil fumarate plus either lamivudine or emtricitabine, without universal access to genotyping, was non-inferior in achieving viral suppression compared with ritonavir-boosted darunavir plus two NRTIs. These global data support the most recent WHO treatment guidelines.

FUNDING

UNITAID; National Institute of Allergy and Infectious Diseases, USA; National Health and Medical Research Council, Australia; ViiV Healthcare; and Janssen.

Optimising HIV drug resistance testing laboratory networks in Kenya: insights from systems engineering modelling

BACKGROUND

HIV drug resistance (DR) is a growing threat to the durability of current and future HIV treatment success. DR testing (DRT) technologies are very expensive and specialised, relying on centralised laboratories in most low and middle-income countries. Modelling for laboratory network with point-of-care (POC) DRT assays to minimise turnaround time (TAT), is urgently needed to meet the growing demand.

METHODS

We developed a model with user-friendly interface using integer programming and queueing theory to improve the DRT system in Kisumu County, Kenya. We estimated DRT demand based on both current and idealised scenarios and evaluated a centralised laboratory-only network and an optimised POC DRT network. A one-way sensitivity analysis of key user inputs was conducted.

RESULTS

In a centralised laboratory-only network, the mean TAT ranged from 8.52 to 8.55 working days, and the system could not handle a demand proportion exceeding 1.6%. In contrast, the mean TAT for POC DRT network ranged from 1.13 to 2.11 working days, with demand proportion up to 4.8%. Sensitivity analyses showed that expanding DRT hubs reduces mean TAT substantially while increasing the processing rate at national labs had minimal effect. For instance, doubling the current service rate at national labs reduced the mean TAT by only 0.0%-1.9% in various tested scenarios, whereas doubling the current service rate at DRT hubs reduced the mean TAT by 37.5%-49.8%. In addition, faster batching modes and transportation were important factors influencing the mean TAT.

CONCLUSIONS

Our model offers decision-makers an informed framework for improving the DRT system using POC in Kenya. POC DRT networks substantially reduce mean TAT and can handle a higher demand proportion than a centralised laboratory-only network, especially for children and pregnant women living with HIV, where there is an immediate push to use DRT results for patient case management.

Prevalence of Emergent Dolutegravir Resistance Mutations in People Living with HIV: A Rapid Scoping Review

BACKGROUND

Dolutegravir (DTG) is a cornerstone of global antiretroviral (ARV) therapy (ART) due to its high efficacy and favorable tolerability. However, limited data exist regarding the risk of emergent integrase strand transfer inhibitor (INSTI) drug-resistance mutations (DRMs) in individuals receiving DTG-containing ART.

METHODS

We performed a PubMed search using the term "Dolutegravir", last updated 18 December 2023, to estimate the prevalence of VF with emergent INSTI DRMs in people living with HIV (PLWH) without previous VF on an INSTI who received DTG-containing ART.

RESULTS

Of 2131 retrieved records, 43 clinical trials, 39 cohorts, and 6 cross-sectional studies provided data across 6 clinical scenarios based on ART history, virological status, and co-administered ARVs: (1) ART-naïve PLWH receiving DTG plus two NRTIs; (2) ART-naïve PLWH receiving DTG plus lamivudine; (3) ART-experienced PLWH with VF on a previous regimen receiving DTG plus two NRTIs; (4) ART-experienced PLWH with virological suppression receiving DTG plus two NRTIs; (5) ART-experienced PLWH with virological suppression receiving DTG and a second ARV; and (6) ART-experienced PLWH with virological suppression receiving DTG monotherapy. The median proportion of PLWH in clinical trials with emergent INSTI DRMs was 1.5% for scenario 3 and 3.4% for scenario 6. In the remaining four trial scenarios, VF prevalence with emergent INSTI DRMs was ≤0.1%. Data from cohort studies minimally influenced prevalence estimates from clinical trials, whereas cross-sectional studies yielded prevalence data lacking denominator details.

CONCLUSIONS

In clinical trials, the prevalence of VF with emergent INSTI DRMs in PLWH receiving DTG-containing regimens has been low. Novel approaches are required to assess VF prevalence with emergent INSTI DRMs in PLWH receiving DTG in real-world settings.

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.

Clinical outcomes with second-line dolutegravir in people with virological failure on first-line non-nucleoside reverse transcriptase inhibitor-based regimens in South Africa: a retrospective cohort study

BACKGROUND

Dolutegravir (DTG) is recommended for second-line antiretroviral therapy (ART) after virological failure on first-line non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimens in people living with HIV in low-income and middle-income countries. We compared the effectiveness of DTG versus the previously recommended ritonavir-boosted lopinavir (LPV/r) regimen for second-line treatment in South Africa.

METHODS

In this retrospective observational cohort study, we used routinely collected, de-identified data from 59 primary health-care facilities in eThekwini Municipality, KwaZulu-Natal, South Africa. We included people living with HIV aged 15 years or older with virological failure (defined as two consecutive viral loads of ≥1000 copies per mL at least 56 days apart) on first-line NNRTI-based ART containing tenofovir disoproxil fumarate (TDF) and who switched to second-line ART. Our primary outcomes were retention in care and viral suppression (<50 copies per mL) at 12 months after starting second-line treatment. We used modified Poisson regression models to compare these outcomes between second-line regimens (zidovudine [AZT]/emtricitabine or lamivudine [XTC]/DTG; TDF/XTC/DTG; and AZT/XTC/LPV/r).

FINDINGS

We included 1214 participants in our study, of whom 729 (60%) were female and 485 (40%) were male, and whose median age was 36 years (IQR 30-42). 689 (57%) were switched to AZT/XTC/LPV/r, 217 (18%) to AZT/XTC/DTG, and 308 (25%) to TDF/XTC/DTG. Compared with AZT/XTC/LPV/r (75%), retention in care was higher with AZT/XTC/DTG (86%, adjusted risk ratio [aRR]=1·14, 95% CI 1·03-1·27; adjusted risk difference [aRD]=10·89%, 95% CI 2·01 to 19·78) but similar with TDF/XTC/DTG (77%, aRR=1·01, 0·94-1·10; aRD=1·04%, -5·03 to 7·12). Observed retention in care was lower with TDF/XTC/DTG than with AZT/XTC/DTG, although in multivariable analysis evidence for a difference was weak (aRR=0·89, 0·78-1·01, p=0·060; aRD=-9·85%, -20·33 to 0·63, p=0·066). Of 799 participants who were retained in care with a 12-month viral load test done, viral suppression was higher with AZT/XTC/DTG (59%; aRR=1·25, 1·06-1·47; aRD=11·57%, 2·37 to 20·76) and higher with TDF/XTC/DTG (61%; aRR=1·30, 1·14-1·48; aRD=14·16%, 7·14 to 21·18) than with AZT/XTC/LPV/r (47%).

INTERPRETATION

These findings from routine care support further implementation of WHO's recommendation to use DTG instead of LPV/r in people living with HIV who experience virological failure while receiving first-line NNRTI-based ART.

FUNDING

Bill & Melinda Gates Foundation.

TRANSLATION

For the isiZulu translation of the abstract see Supplementary Materials section.

Virological Findings and Treatment Outcomes of Cases That Developed Dolutegravir Resistance in Malawi's National HIV Treatment Program

Millions of Africans are on dolutegravir-based antiretroviral therapy (ART), but few detailed descriptions of dolutegravir resistance and its clinical management exist. We reviewed HIV drug resistance (HIVDR) testing application forms submitted between June 2019 and October 2022, data from the national HIVDR database, and genotypic test results. We obtained standardized ART outcomes and virological results of cases with dolutegravir resistance, and explored associations with dolutegravir resistance among individuals with successful integrase sequencing. All cases were on two nucleoside reverse transcriptase inhibitors (NRTIs)/dolutegravir, and had confirmed virological failure, generally with prolonged viremia. Among 89 samples with successful integrase sequencing, 24 showed dolutegravir resistance. Dolutegravir resistance-associated mutations included R263K (16/24), E138K (7/24), and G118R (6/24). In multivariable logistic regression analysis, older age and the presence of high-level NRTI resistance were significantly associated with dolutegravir resistance. After treatment modification recommendations, four individuals (17%) with dolutegravir resistance died, one self-discontinued ART, one defaulted, and one transferred out. Of the 17 remaining individuals, 12 had follow-up VL results, and 11 (92%) were <1000 copies/mL. Twenty-four cases with dolutegravir resistance among 89 individuals with confirmed virological failure suggests a considerable prevalence in the Malawi HIV program. Successful management of dolutegravir resistance was possible, but early mortality was high. More research on the management of treatment-experienced individuals with dolutegravir resistance is needed.

Outcomes and characteristics of patients on protease inhibitors at a tertiary level antiretroviral clinic

Background

Protease inhibitors (PIs) have been recommended as World Health Organization second-line antiretroviral therapy (ART) for low- to middle-income countries for two decades. As dolutegravir-based regimens have become widely available, the future role of PIs is uncertain.

Objectives

To describe the characteristics of patients on PI-based ART (in first-line and second-line regimens), double-boosted protease inhibitors (DBPI) and patients who received recycled nucleoside reverse transcriptase inhibitors (NRTI) in second-line regimens at a tertiary level ART clinic.

Method

We conducted a descriptive retrospective record review of adult patients on PI-based ART who attended Nthabiseng Adult Infectious Diseases Clinic at Chris Hani Baragwanath Academic Hospital in Soweto, South Africa, between January 2021 and April 2022.

Results

Of the 900 patients sampled, 543 (60.3%) were female, the median age was 45 and 703 (79.1%) had viral loads (VL) below 1000 copies/mL. In contrast, 21 (58.3%) of 36 vertically infected patients had VLs below 1000 copies/mL. Thirty-seven (4.1%) patients were on DBPIs. The commonest reason for DBPI use in 24 (64.9%) patients was drug resistance test (DRT)-guided switch after virological failure. Forty-nine (5.4%) patients were on recycled NRTIs with no DRT, and 24 (2.6%) patients were on NRTIs to which there was documented resistance. Outcomes for these patients were similar to the total sample.

Conclusion

PIs have long been a cornerstone of second-line ART. This study demonstrates the real-world utility of PIs, as well as their disadvantages. There was no difference in the outcomes of patients who received recycled NRTIs in second-line regimens.

Integrase inhibitors: current protagonists in antiretroviral therapy

Since HIV was identified as the etiological agent of AIDS, there have been significant advances in antiretroviral therapy (ART) that has reduced morbidity/mortality. Still, the viral genome's high mutation rate, suboptimal ART regimens, incomplete adherence to therapy and poor control of the viral load generate variants resistant to multiple drugs. Licensing over 30 anti-HIV drugs worldwide, including integrase inhibitors, has marked a milestone since they are potent and well-tolerated drugs. In addition, they favor a faster recovery of CD4+ T cells. They also increase the diversity profile of the gut microbiota and reduce inflammatory markers. All of these highlight the importance of including them in different ART regimens.

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.

Virologic Response to Dolutegravir Plus Lamivudine in People With Suppressed Human Immunodeficiency Virus Type 1 and Historical M184V/I: A Systematic Literature Review and Meta-analysis

Background

To investigate the impact of the M184V/I mutation on virologic response to dolutegravir plus lamivudine (DTG + 3TC) in suppressed-switch populations, a meta-analysis was performed using virologic outcomes from people with human immunodeficiency virus type 1 (PWH) with and without M184V/I before DTG + 3TC switch in real-world studies identified via systematic literature review. Sensitivity analyses were performed using data from PWH with M184V/I in interventional studies identified via targeted literature review.

Methods

Single-arm meta-analyses using common- and random-effects models were used to estimate proportions of PWH with virologic failure (VF) among real-world populations with and without M184V/I and interventional study participants with M184V/I at 24, 48, and 96 weeks.

Results

Literature reviews identified 5 real-world studies from 3907 publications and 51 abstracts meeting inclusion criteria and 5 interventional studies from 1789 publications and 3 abstracts. All time points had low VF incidence in PWH with M184V/I (real-world: 1.43%-3.81%; interventional: 0.00%) and without (real-world: 0.73%-2.37%). Meta-analysis-estimated proportions (95% confidence interval) with VF were low at weeks 24, 48, and 96, respectively, for PWH with M184V/I (real-world: 0.01 [.00-.04], 0.03 [.01-.06], and 0.04 [.01-.07]; interventional: 0.00 [.00-.02], 0.00 [.00-.01], and 0.00 [.00-.03]) and without (real-world: 0.00 [.00-.02], 0.02 [.01-.04], and 0.02 [.00-.05]). One real-world study (n = 712) reported treatment-emergent M184V at VF in 1 of 652 (0.15%) PWH without prior M184V/I.

Conclusions

Results suggest that prior M184V/I has minimal impact on virologic suppression after switching to DTG + 3TC and provide reassurance when considering switching regimens in virologically suppressed PWH with incomplete treatment history or limited treatment options.

Current drugs for HIV-1: from challenges to potential in HIV/AIDS

The human immunodeficiency virus (HIV) persists in latently infected CD4+T cells and integrates with the host genome until cell death. Acquired immunodeficiency syndrome (AIDS) is associated with HIV-1. Possibly, treating HIV/AIDS is an essential but challenging clinical goal. This review provides a detailed account of the types and mechanisms of monotherapy and combination therapy against HIV-1 and describes nanoparticle and hydrogel delivery systems. In particular, the recently developed capsid inhibitor (Lenacapavir) and the Ainuovirine/tenofovir disoproxil fumarate/lamivudine combination (ACC008) are described. It is interestingly to note that the lack of the multipass transmembrane proteins serine incorporator 3 (SERINC3) and the multipass transmembrane proteins serine incorporator 5 (SERINC5) may be one of the reasons for the enhanced infectivity of HIV-1. This discovery of SERINC3 and SERINC5 provides new ideas for HIV-1 medication development. Therefore, we believe that in treating AIDS, antiviral medications should be rationally selected for pre-exposure and post-exposure prophylaxis to avoid the emergence of drug resistance. Attention should be paid to the research and development of new drugs to predict HIV mutations as accurately as possible and to develop immune antibodies to provide multiple guarantees for the cure of AIDS.

Virologic Outcomes and ARV Switch Profiles 2 Years After National Rollout of Dolutegravir to Children Less Than 15 Years in Southern Mozambique

BACKGROUND

Dolutegravir (DTG) was scaled up globally to optimize treatment for children living with HIV. We evaluated the rollout and virological outcomes after DTG introduction in Mozambique.

METHODS

Data from children 0-14 years with visits from September 2019 to August 2021 were extracted from records in 16 facilities in 12 districts. Among children ever on DTG, we report treatment switches, defined as changes in anchor drug, regardless of changes to nucleoside reverse transcriptase inhibitor (NRTI) backbones. Among those on DTG for ≥6 months, we described viral load suppression rates by children newly initiating and switching to DTG and by the NRTI backbone at the time of the DTG switch.

RESULTS

Overall, 3,347 children were ever on DTG-based treatment (median age 9.5 years; 52.8% female). Most children (3,202, 95.7%) switched to DTG from another antiretroviral regimen. During the 2-year follow-up, 9.9% never switched from DTG; 52.7% had 1 regimen change, of which 97.6% were switched to DTG. However, 37.2% of children experienced ≥2 anchor drug changes. Overall median time on DTG was 18.6 months; nearly all children ≥5 years (98.6%) were on DTG at the last visit. Viral suppression was 79.7% (63/79) for children newly initiating DTG and 85.8% (1,775/2,068) for those switching to DTG. Suppression rates were 84.8% and 85.7% among children who switched and maintained NRTI backbones, respectively.

CONCLUSIONS

Viral suppression rates of ≥80% with minor variations by backbone were achieved during the 2-year DTG rollout. However, there were multiple anchor drug switches for over one-third of children, which may be attributable in part to drug stockouts. Long-term pediatric HIV management will only be successful with immediate and sustainable access to optimized child-friendly drugs and formulations.

Association of cytokine gene polymorphisms with peripheral neuropathy susceptibility in people living with HIV in Greece

Relatively little research has been done in recent years to understand what leads to the unceasingly high rates of HIV sensory neuropathy despite successful antiretroviral treatment. In vivo and in vitro studies demonstrate neuronal damage induced by HIV and increasingly identified ART neurotoxicity involving mitochondrial dysfunction and innate immune system activation in peripheral nerves, ultimately all pathways resulting in enhanced pro-inflammatory cytokine secretion. Furthermore, many infectious/autoimmune/malignant diseases are influenced by the production-profile of pro-inflammatory and anti-inflammatory cytokines, due to inter-individual allelic polymorphism within cytokine gene regulatory regions. Associations of cytokine gene polymorphisms are investigated with the aim of identifying potential genetic markers for susceptibility to HIV peripheral neuropathy including ART-dependent toxic neuropathy. One hundred seventy-one people living with HIV in Northern Greece, divided into two sub-groups according to the presence/absence of peripheral neuropathy, were studied over a 5-year period. Diagnosis was based on the Brief Peripheral Neuropathy Screening. Cytokine genotyping was performed by sequence-specific primer-polymerase chain reaction. Present study findings identify age as an important risk factor (p < 0.01) and support the idea that cytokine gene polymorphisms are at least involved in HIV peripheral-neuropathy pathogenesis. Specifically, carriers of IL1a-889/rs1800587 TT genotype and IL4-1098/rs2243250 GG genotype disclosed greater relative risk for developing HIV peripheral neuropathy (OR: 2.9 and 7.7 respectively), while conversely, carriers of IL2+166/rs2069763 TT genotype yielded lower probability (OR: 3.1), all however, with marginal statistical significance. The latter, if confirmed in a larger Greek population cohort, may offer in the future novel genetic markers to identify susceptibility, while it remains significant that further ethnicity-oriented studies continue to be conducted in a similar pursuit.

Effectiveness of second-generation integrase strand-transfer inhibitor-based regimens for antiretroviral-experienced people with HIV who had viral rebound

BACKGROUND

Antiretroviral regimens containing a second-generation integrase strand-transfer inhibitor (INSTI) plus 2 nucleos(t)ide reverse-transcriptase inhibitors (NRTIs) are the recommended therapy for people with HIV (PWH) who are antiretroviral-naïve or on stable antiretroviral therapy (ART) with viral suppression. Real-world data on the virologic effectiveness of co-formulated bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) among PWH with virologic failure while receiving other ART remain sparse.

METHODS

We retrospectively reviewed the medical records of PWH who had viral rebound with plasma HIV RNA >1000 copies/mL and were switched to either dolutegravir combined with 2 NRTIs or BIC/FTC/TAF. The primary end point was re-achieving viral suppression within the first 48 weeks of switch. The association between NRTI-related resistance-associated mutations (RAMs) and virologic effectiveness was examined.

RESULTS

Seventy-nine PWH with viral rebound while receiving other antiretroviral regimens were included. Within the first 48 weeks of switch, the overall probability of re-achieving viral suppression was 79.7% (82.5% [33/40] and 76.9% [30/39] for BIC/FTC/TAF and dolutegravir-based regimens, respectively, p = 0.78). PWH with a higher CD4 lymphocyte count (adjusted odds ratio, per 100-cell/mm3 increase, 1.41; 95% confidence interval, 1.02-1.95) were more likely to re-achieve viral suppression. Among PWH switching to BIC/FTC/TAF who had pre-existing RAMs to NRTIs before switch, 14 of 15 (93.3%) successfully achieved viral suppression.

CONCLUSIONS

Switching to BIC/FTC/TAF and dolutegravir-based regimens could re-achieve viral suppression in four-fifth of the PWH who experienced viral rebound during treatment with other antiretroviral regimens. Pre-existing NRTI-related RAMs did not have adverse impact on the effectiveness of dolutegravir combined with 2 NRTIs or BIC/FTC/TAF.

Treatment Emergent Dolutegravir Resistance Mutations in Individuals Naïve to HIV-1 Integrase Inhibitors: A Rapid Scoping Review

Background: Dolutegravir (DTG)-based antiretroviral therapy (ART) rarely leads to virological failure (VF) and drug resistance in integrase strand transfer inhibitor (INSTI)-naïve persons living with HIV (PLWH). As a result, limited data are available on INSTI-associated drug resistance mutations (DRMs) selected by DTG-containing ART regimens. Methods: We reviewed studies published through July 2023 to identify those reporting emergent major INSTI-associated DRMs in INSTI-naïve PLWH receiving DTG and those containing in vitro DTG susceptibility results using a standardized assay. Results: We identified 36 publications reporting 99 PLWH in whom major nonpolymorphic INSTI-associated DRMs developed on a DTG-containing regimen and 21 publications containing 269 in vitro DTG susceptibility results. DTG-selected DRMs clustered into four largely non-overlapping mutational pathways characterized by mutations at four signature positions: R263K, G118R, N155H, and Q148H/R/K. Eighty-two (82.8%) viruses contained just one signature DRM, including R263K (n = 40), G118R (n = 24), N155H (n = 9), and Q148H/R/K (n = 9). Nine (9.1%) contained ≥1 signature DRM, and eight (8.1%) contained just other DRMs. R263K and G118R were negatively associated with one another and with N155H and Q148H/K/R. R263K alone conferred a median 2.0-fold (IQR: 1.8-2.2) reduction in DTG susceptibility. G118R alone conferred a median 18.8-fold (IQR:14.2-23.4) reduction in DTG susceptibility. N155H alone conferred a median 1.4-fold (IQR: 1.2-1.6) reduction in DTG susceptibility. Q148H/R/K alone conferred a median 0.8-fold (IQR: 0.7-1.1) reduction in DTG susceptibility. Considerably higher levels of reduced susceptibility often occurred when signature DRMs occurred with additional INSTI-associated DRMs. Conclusions: Among INSTI-naïve PLWH with VF and treatment emergent INSTI-associated DRMs, most developed one of four signature DRMs, most commonly R263K or G118R. G118R was associated with a much greater reduction in DTG susceptibility than R263K.

Low Prevalence of Pre-Treatment and Acquired Drug Resistance to Dolutegravir among Treatment Naïve Individuals Initiating on Tenofovir, Lamivudine and Dolutegravir in Zimbabwe

Dolutegravir (DTG) use in combination with tenofovir and lamivudine (TLD) is scaling up in Africa. However, HIV drug resistance (HIVDR) data to DTG remain scarce in Zimbabwe. We assessed the prevalence and genetic mechanisms of DTG resistance in people living with HIV initiating on TLD. A prospective cohort study was conducted between October 2021 and April 2023 among antiretroviral therapy (ART) naïve adults (≥18 years) attending care at an HIV clinic in Zimbabwe. Pre-treatment drug resistance (PDR) was assessed prior to TLD initiation and viral load (VL) outcome and acquired drug resistance (ADR) to TLD were described after 24 weeks follow-up. In total, 172 participants were enrolled in the study. The median (IQR) age and log10 VL were 39 (29-48) years and 5.41 (4.80-5.74) copies/mL, respectively. At baseline, no PDR to DTG was found. However, as previously reported, PDR to non-nucleotide reverse transcriptase inhibitor (NNRTI) was high (15%) whilst PDR to NRTI was low (4%). After a median duration of 27 (25-30) weeks on TLD, virological suppression (VL < 1000 copies/mL) was 98% and among the 2 participants with VL ≥ 1000 copies/mL, no ADR was found. HIVDR to DTG is rare among ART naïve individuals. DTG is more likely to address the problems of HIVDR in Africa.

HIV infection

The AIDS epidemic has been a global public health issue for more than 40 years and has resulted in ~40 million deaths. AIDS is caused by the retrovirus, HIV-1, which is transmitted via body fluids and secretions. After infection, the virus invades host cells by attaching to CD4 receptors and thereafter one of two major chemokine coreceptors, CCR5 or CXCR4, destroying the host cell, most often a T lymphocyte, as it replicates. If unchecked this can lead to an immune-deficient state and demise over a period of ~2-10 years. The discovery and global roll-out of rapid diagnostics and effective antiretroviral therapy led to a large reduction in mortality and morbidity and to an expanding group of individuals requiring lifelong viral suppressive therapy. Viral suppression eliminates sexual transmission of the virus and greatly improves health outcomes. HIV infection, although still stigmatized, is now a chronic and manageable condition. Ultimate epidemic control will require prevention and treatment to be made available, affordable and accessible for all. Furthermore, the focus should be heavily oriented towards long-term well-being, care for multimorbidity and good quality of life. Intense research efforts continue for therapeutic and/or preventive vaccines, novel immunotherapies and a cure.

Clinical outcomes after the introduction of dolutegravir for second-line antiretroviral therapy in South Africa: a retrospective cohort study

Background

Dolutegravir is now recommended for second-line anti-retroviral therapy (ART) in low- and middle-income countries. We compared outcomes with dolutegravir (DTG) versus the previous lopinavir/ritonavir (LPV/r) regimen in South Africa.

Methods

We used routinely collected, de-identified data from 59 South African clinics. We included people living with HIV aged ≥ 15 years with virologic failure (two consecutive viral loads ≥1000 copies/mL) on first-line tenofovir disoproxil fumarate (TDF)-based ART and switched to second-line ART. We used modified Poisson regression models to compare outcomes of 12-month retention-in-care and viral suppression (<50 copies/ml) after switching to second-line regimens of zidovudine (AZT), emtricitabine/lamivudine (XTC), DTG and TDF/XTC/DTG and AZT/XTC/LPV/r.

Findings

Of 1214 participants, 729 (60.0%) were female, median age was 36 years (interquartile range 30 to 42), 689 (56.8%) were switched to AZT/XTC/LPV/r, 217 (17.9%) to AZT/XTC/DTG and 308 (25.4%) to TDF/XTC/DTG. Retention-in-care was higher with AZT/XTC/DTG (85.7%, adjusted risk ratio (aRR) 1.14, 95% confidence interval (CI) 1.03 to 1.27; adjusted risk difference (aRD) 10.89%, 95%CI 2.01 to 19.78) but not different with TDF/XTC/DTG (76.9%, aRR 1.01, 95%CI 0.94 to 1.10; aRD 1.04%, 95%CI -5.03 to 7.12) compared to AZT/XTC/LPV/r (75.2%). Retention-in-care with TDF/XTC/DTG was not statistically significantly different from AZT/XTC/DTG (aRR 0.89, 95%CI 0.78 to 1.01; aRD -9.85%, 95%CI -20.33 to 0.63). Of 799 participants who were retained-in-care with a 12-month viral load, viral suppression was higher with AZT/XTC/DTG (59.3%, aRR 1.25, 95%CI 1.06 to 1.47; aRD 11.57%, 95%CI 2.37 to 20.76) and TDF/XTC/DTG (60.7%, aRR 1.30, 95%CI 1.14 to 1.48; aRD 14.16%, 95%CI 7.14 to 21.18) than with the AZT/XTC/LPV/r regimen (46.7%).

Interpretation

DTG-based second-line regimens were associated with similar or better retention-in-care and better viral suppression than the LPV/r-based regimen. TDF/XTC/DTG had similar viral suppression compared to AZT/XTC/DTG.

Funding

Bill & Melinda Gates Foundation, Africa Oxford Initiative.

Advancing HIV Drug Resistance Technologies and Strategies: Insights from South Africa's Experience and Future Directions for Resource-Limited Settings

Monitoring of HIV drug resistance (HIVDR) remains critical for ensuring countries attain and sustain the global goals for ending HIV as a public health threat by 2030. On an individual patient level, drug resistance results assist in ensuring unnecessary treatment switches are avoided and subsequent regimens are tailored on a case-by-case basis, should resistance be detected. Although there is a disparity in access to HIVDR testing in high-income countries compared to low- and middle-income countries (LMICS), more LMICs have now included HIVDR testing for individual patient management in some groups of patients. In this review, we describe different strategies for surveillance as well as where HIVDR testing can be implemented for individual patient management. In addition, we briefly review available technologies for HIVDR testing in LMICs, including Sanger sequencing, next-generation sequencing, and some point-of-care options. Finally, we describe how South Africa has implemented HIVDR testing in the public sector.

Second-Line Switch to Dolutegravir for Treatment of HIV Infection

BACKGROUND

Data to inform the switch from a ritonavir-boosted protease inhibitor (PI) to dolutegravir in patients living with human immunodeficiency virus (HIV) infection who do not have genotype information and who have viral suppression with second-line therapy containing a ritonavir-boosted PI have been limited.

METHODS

In a prospective, multicenter, open-label trial conducted at four sites in Kenya, we randomly assigned, in a 1:1 ratio, previously treated patients without genotype information who had viral suppression while receiving treatment containing a ritonavir-boosted PI to either switch to dolutegravir or continue the current regimen. The primary end point was a plasma HIV type 1 RNA level of at least 50 copies per milliliter at week 48, assessed on the basis of the Food and Drug Administration snapshot algorithm. The noninferiority margin for the between-group difference in the percentage of participants who met the primary end point was 4 percentage points. Safety up to week 48 was assessed.

RESULTS

A total of 795 participants were enrolled, with 398 assigned to switch to dolutegravir and 397 assigned to continue taking their ritonavir-boosted PI; 791 participants (397 in the dolutegravir group and 394 in the ritonavir-boosted PI group) were included in the intention-to-treat exposed population. At week 48, a total of 20 participants (5.0%) in the dolutegravir group and 20 (5.1%) in the ritonavir-boosted PI group met the primary end point (difference, -0.04 percentage points; 95% confidence interval, -3.1 to 3.0), a result that met the criterion for noninferiority. No mutations conferring resistance to dolutegravir or the ritonavir-boosted PI were detected at the time of treatment failure. The incidence of treatment-related grade 3 or 4 adverse events was similar in the dolutegravir group and the ritonavir-boosted PI group (5.7% and 6.9%, respectively).

CONCLUSIONS

In previously treated patients with viral suppression for whom there were no data regarding the presence of drug-resistance mutations, dolutegravir treatment was noninferior to a regimen containing a ritonavir-boosted PI when the patients were switched from a ritonavir-boosted PI-based regimen. (Funded by ViiV Healthcare; 2SD ClinicalTrials.gov number, NCT04229290.).

Bictegravir/emtricitabine/tenofovir alafenamide plus doravirine in highly treatment-experienced men with multidrug-resistant HIV

OBJECTIVE

To evaluate the safety and efficacy of switching highly treatment-experienced people with HIV (HTE PWH) from rilpivirine/emtricitabine/tenofovir alafenamide (RPV/FTC/TAF) plus dolutegravir (DTG) to bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) plus doravirine (DOR). A pharmacokinetic (PK) analysis was conducted to assess the potential interaction between BIC and DOR.

DESIGN AND METHODS

This open-label switch trial enrolled HTE PWH from a primary care private practice in the United States. Eligible participants were male, aged ≥45 years, with documented viral resistance to protease inhibitors, nucleoside reverse transcriptase inhibitors, and/or nonnucleoside reverse transcriptase inhibitors but no resistance to RPV or DOR, and no K65R or T69 insertion mutations. Virologic suppression (≤50 copies/ml) while on RPV/FTC/TAF plus DTG for ≥6 months was required prior to enrollment. The primary endpoint of the study was virologic suppression (<50 and <200 copies/ml) at 48 weeks. Secondary endpoints included safety, tolerability, changes in body mass index (BMI), and identification of PK parameters of BIC and DOR.

RESULTS

Twenty males [median age: 65 years (range, 46-74), median time since HIV diagnosis: 37 years (range, 12-42)] completed the study. BIC/FTC/TAF plus DOR was well tolerated with no serious or treatment-related adverse events reported and no appreciable changes in BMI from baseline to Week 48. At Week 48, 100% of participants had <50 viral copies/ml. PK parameters for BIC and DOR ( n  = 10) were consistent with published data.

CONCLUSIONS

Switching from RPV/FTC/TAF plus DTG to BIC/FTC/TAF plus DOR was well tolerated and efficacious in HTE men aged ≥45 years with HIV.

The G118R plus R263K Combination of Integrase Mutations Associated with Dolutegravir-Based Treatment Failure Reduces HIV-1 Replicative Capacity and Integration

Human immunodeficiency virus (HIV) treatment with antiretroviral regimens containing integrase strand transfer inhibitors such as dolutegravir (DTG) and bictegravir (BIC) offers high levels of protection against the development of drug resistance mutations. Despite this, resistance to DTG and BIC can occur through the development of the R263K integrase substitution. Failure with DTG has also been associated with the emergence of the G118R substitution. G118R and R263K are usually found separately but have been reported together in highly treatment-experienced persons who experienced treatment failure with DTG. We used cell-free strand transfer and DNA binding assays and cell-based infectivity, replicative capacity, and resistance assays to characterize the G118R plus R263K combination of integrase mutations. R263K reduced DTG and BIC susceptibility ~2-fold, in agreement with our previous work. Single-cycle infectivity assays showed that G118R and G118R plus R263K conferred ~10-fold resistance to DTG. G118R alone conferred low levels of resistance to BIC (3.9-fold). However, the G118R plus R263K combination conferred high levels of resistance to BIC (33.7-fold), likely precluding the use of BIC after DTG failure with the G118R plus R263K combination. DNA binding, viral infectivity, and replicative capacity of the double mutant were further impaired, compared to single mutants. We propose that impaired fitness helps to explain the scarcity of the G118R plus R263K combination of integrase substitutions in clinical settings and that immunodeficiency likely contributes to its development.

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.

Recycling Tenofovir in Second-line Antiretroviral Treatment With Dolutegravir: Outcomes and Viral Load Trajectories to 72 weeks

BACKGROUND

Recycling tenofovir and lamivudine/emtricitabine with dolutegravir (TLD) after failure of non-nucleoside transcriptase inhibitor first-line antiretroviral therapy is more tolerable and scalable than dolutegravir plus optimized nucleoside reverse transcriptase inhibitors. Studies have demonstrated TLD's efficacy as second line, but long-term follow-up is limited.

METHODS

ARTIST is a single arm, prospective, interventional study conducted in Khayelitsha, South Africa, which switched 62 adults with 2 viral loads >1000 copies/mL from tenofovir, lamivudine/emtricitabine, and an non-nucleoside transcriptase inhibitor to TLD. We report efficacy to 72 weeks and, in a post hoc analysis, evaluated viral load trajectories of individuals with viremic episodes.

RESULTS

Virologic suppression was 86% [95% confidence interval (CI) 74 to 93], 74% (95% CI: 61 to 84), and 75% (95% CI: 63 to 86) <50 copies/mL and 95%, 84%, and 77% <400 copies/mL at week 24, 48, and 72, respectively, with 89% (50/56) resistant (Stanford score ≥15) to tenofovir and/or lamivudine preswitch. No participants developed integrase-inhibitor resistance. Of the 20 participants not suppressed at week 24 and/or 48, 2 developed virologic failure, 1 switched regimen (adverse event), 2 were lost to follow-up, 1 missed the visit, 1 transferred out, 9 resuppressed <50 copies/mL with enhanced adherence counseling, and 4 remained viremic (3 with <200 copies/mL) at week 72.

CONCLUSIONS

Recycling NRTIs with dolutegravir was effective for most participants to 72 weeks. Most with viremia did not develop virologic failure and subsequently suppressed with enhanced adherence counseling or continued to have low-level viremia. No integrase-inhibitor resistance was detected despite low-level viremia in a minority of participants.

Efficacy of Dolutegravir versus Darunavir in Antiretroviral First-Line Regimens According to Resistance Mutations and Viral Subtype

Background: Dolutegravir (DTG)-based first-line regimens have shown superior efficacy versus darunavir (DRV)-based ones in randomized trials. We compared these two strategies in clinical practice, particularly considering the role of pre-treatment drug resistance mutations (DRMs) and of the HIV-1 subtype. Materials and methods: The multicenter Antiretroviral Resistance Cohort Analysis (ARCA) database was queried to identify HIV-1-positive patients starting a first-line therapy with 2NRTIs plus either DTG or DRV between 2013 and 2019. Only adult (≥18 years) patients with a genotypic resistance test (GRT) prior to therapy and with HIV-1 RNA ≥1000 copies/mL were selected. Through multivariable Cox regressions, we compared DTG- versus DRV-based regimens in the time to virological failure (VF) stratifying for pre-treatment DRMs and the viral subtype. Results: A total of 649 patients was enrolled, with 359 (55.3%) and 290 (44.7) starting DRV and DTG, respectively. In 11 months of median follow-up time, there were 41 VFs (8.4 in 100 patient-years follow-up, PYFU) and 15 VFs (5.3 per 100 PYFU) in the DRV and DTG groups, respectively. Compared with a fully active DTG-based regimen, the risk of VF was higher with DRV (aHR 2.33; p = 0.016), and with DTG-based regimens with pre-treatment DRMs to the backbone (aHR 17.27; p = 0.001), after adjusting for age, gender, baseline CD4 count and HIV-RNA, concurrent AIDS-defining event and months since HIV diagnosis. Compared with patients harboring a B viral subtype and treated with a DTG-based regimen, patients on DRV had an increased risk of VF, both in subtype B (aHR 3.35; p = 0.011), C (aHR 8.10; p = 0.005), CRF02-AG (aHR 5.59; p = 0.006) and G (aHR 13.90; p < 0.001); DTG also demonstrated a reduced efficacy in subtypes C (versus B, aHR 10.24; p = 0.035) and CRF01-AE (versus B; aHR 10.65; p = 0.035). Higher baseline HIV-RNA and a longer time since HIV diagnosis also predicted VF. Conclusions: In line with randomized trials, DTG-based first-line regimens showed an overall superior efficacy compared with DRV-based regimens. GRT may still play a role in identifying patients more at risk of VF and in guiding the choice of an antiretroviral backbone.

We should not stop considering HIV drug resistance testing at failure of first-line antiretroviral therapy

HIV drug resistance is a major global hurdle to successful and sustained antiretroviral therapy. Global guidelines recommend testing for antiretroviral drug resistance and results are used to inform treatment regimen design for patients at different stages of therapy. Several clinical trials investigated optimal regimens after failure of first-line antiretroviral therapy, yielding data that advanced knowledge and informed care. However, further interpretation of data from these studies questioned the benefit of antiretroviral drug resistance testing for cases in which first-line treatment is not effective and, furthermore, that relying on the results of antiretroviral drug resistance testing could be misleading and unnecessary. In this Viewpoint, which is largely focused on high-income settings, we review these data, reflect on the potential problems with their interpretation, and call for caution in their extrapolation. Without negating the importance of the data, and recognising the varied circumstances related to HIV drug resistance testing in different global settings, we advise caution before changing current practice and recommendations. We believe that we should not universally stop considering HIV drug resistance testing at failure of first-line antiretroviral therapy.

Initial supplementary dose of dolutegravir in second-line antiretroviral therapy: a non-comparative, double-blind, randomised placebo-controlled trial

BACKGROUND

Dolutegravir concentrations are reduced by efavirenz induction effect necessitating twice daily dolutegravir dosing when co-administered. Efavirenz induction persists for several weeks after stopping, which could potentially select for dolutegravir resistance if switching occurred with unsuppressed HIV-1 RNA levels and standard dolutegravir dosing. We evaluated the need for a lead-in supplementary dolutegravir dose in adults failing first-line tenofovir-emtricitabine-efavirenz (TEE).

METHODS

We conducted a randomised, double-blind, placebo-controlled, phase 2 trial in Khayelitsha, South Africa. Eligible patients had virologic failure (two consecutive HIV-1 RNA≥1000 copies/mL) on first-line TEE. Participants were randomly assigned (1:1) to switch to tenofovir-lamivudine-dolutegravir (TLD) with a supplementary 50 mg dolutegravir dose or placebo taken 12 hours later for 14 days. Primary outcome was proportion with HIV-1 RNA<50 copies/mL at week 24. This study was not powered to compare arms.

RESULTS

130 participants were randomised (65 to each arm). Median baseline HIV-1 RNA was 4.0 log10 copies/mL and 76% had baseline resistance to both tenofovir and lamivudine. One participant died and two were lost to follow-up. At week 24, 55/64 (86%, 95% confidence interval [CI], 75-93%) in the supplementary dolutegravir arm and 53/65 (82%, 95% CI, 70-90%) in the placebo arm had HIV-1 RNA<50 copies/mL. Grade 3 or 4 adverse events were similar in frequency between arms. None of six participants (3 in each arm) eligible for resistance testing by 24 weeks developed dolutegravir resistance.

CONCLUSIONS

Our findings do not support the need for initial dolutegravir dose adjustment in patients switching to TLD who failed first-line TEE.

Antiretroviral Drugs for Treatment and Prevention of HIV Infection in Adults: 2022 Recommendations of the International Antiviral Society-USA Panel

Importance

Recent advances in treatment and prevention of HIV warrant updated recommendations to guide optimal practice.

Objective

Based on a critical evaluation of new data, to provide clinicians with recommendations on use of antiretroviral drugs for the treatment and prevention of HIV, laboratory monitoring, care of people aging with HIV, substance use disorder and HIV, and new challenges in people with HIV, including COVID-19 and monkeypox virus infection.

Evidence Review

A panel of volunteer expert physician scientists were appointed to update the 2020 consensus recommendations. Relevant evidence in the literature (PubMed and Embase searches, which initially yielded 7891 unique citations, of which 834 were considered relevant) and studies presented at peer-reviewed scientific conferences between January 2020 and October 2022 were considered.

Findings

Initiation of antiretroviral therapy (ART) is recommended as soon as possible after diagnosis of HIV. Barriers to care should be addressed, including ensuring access to ART and adherence support. Integrase strand transfer inhibitor-containing regimens remain the mainstay of initial therapy. For people who have achieved viral suppression with a daily oral regimen, long-acting injectable therapy with cabotegravir plus rilpivirine given as infrequently as every 2 months is now an option. Weight gain and metabolic complications have been linked to certain antiretroviral medications; novel strategies to ameliorate these complications are needed. Management of comorbidities throughout the life span is increasingly important, because people with HIV are living longer and confronting the health challenges of aging. In addition, management of substance use disorder in people with HIV requires an evidence-based, integrated approach. Options for preexposure prophylaxis include oral medications (tenofovir disoproxil fumarate or tenofovir alafenamide plus emtricitabine) and, for the first time, a long-acting injectable agent, cabotegravir. Recent global health emergencies, like the SARS-CoV-2 pandemic and monkeypox virus outbreak, continue to have a major effect on people with HIV and the delivery of services. To address these and other challenges, an equity-based approach is essential.

Conclusions and Relevance

Advances in treatment and prevention of HIV continue to improve outcomes, but challenges and opportunities remain.

Switching to coformulated bictegravir, emtricitabine, and tenofovir alafenamide maintained viral suppression in adults with historical virological failures and K65N/R mutation

OBJECTIVES

Real-world experience with coformulated bictegravir, emtricitabine, and tenofovir alafenamide (BIC/FTC/TAF) is sparse as a switch regimen among people living with HIV (PLWH) having achieved viral suppression after previous virologic failures with the emergence of K65N/R.

METHODS

In this retrospective study, PLWH aged ≥20 years who had previous virologic failures with emergent K65N/R were included for switching to BIC/FTC/TAF after having achieved plasma HIV RNA load (PVL) <200 copies/ml for ≥3 months. PLWH were excluded if integrase inhibitor resistance-associated mutations were detected. The primary end point was losing virologic control (PVL >50 copies/ml) at week 48 using a modified US Food and Drug Administration snapshot algorithm.

RESULTS

A total of 72 PLWH with K65N/R who switched to BIC/FTC/TAF were identified. A total of 42 (59.7%) had concurrent M184V/I, and 9 (12.5%) had ≥1 thymidine analog mutations. The median duration of viral suppression was 4.7 years (interquartile range 2.3-5.8), and 97.2% (n = 70) had PVL <50 copies/ml before switching. After a median observation of 98.6 weeks (interquartile range 77.9-120.3), 94.4% (n = 68) continued BIC/FTC/TAF. At week 48, the rate of losing virologic control was 2.8% (2/72). M184V/I was not associated with viral rebound.

CONCLUSION

Despite the emergence of K65N/R +/- M184V/I after virologic failures, BIC/FTC/TAF could be an option for simplification after viral suppression.

Genotypic correlates of resistance to the HIV-1 strand transfer integrase inhibitor cabotegravir

Cabotegravir (CAB) is an integrase strand transfer inhibitor (INSTI) formulated as a long-acting injectable drug approved for pre-exposure prophylaxis and use with a long acting rilpivirine formulation for therapy in patients with virological suppression. However, there has been no comprehensive review of the genetic mechanisms of CAB resistance. Studies reporting the selection of drug resistance mutations (DRMs) by CAB and the results of in vitro CAB susceptibility testing were reviewed. The impact of integrase mutations on CAB susceptibility was assessed using regularized regression analysis. The most commonly selected mutations in the 24 persons developing virological failure while receiving CAB included Q148R (n = 15), N155H (n = 7), and E138K (n = 5). T97A, G118R, G140 A/R/S, and R263K each developed in 1-2 persons. With the exception of T97A, G118R, and G140 A/R, these DRMs were also selected in vitro while G140R was selected in the SIV macaque model. Although these DRMs are similar to those occurring in persons receiving the related INSTI dolutegravir, Q148R was more likely to occur with CAB while G118R and R263K were more likely to occur with dolutegravir. Regularized regression analysis identified 14 DRMs significantly associated with reduced CAB susceptibility including six primary DRMs which reduced susceptibility on their own including G118R, Q148 H/K/R, N155H, and R263K, and eight accessory DRMs including M50I, L74 F/M, T97A, E138K, and G140 A/C/S. Isolates with Q148 H/K/R in combination with L74M, E138 A/K, G140 A/S, and N155H often had >10-fold reduced CAB susceptibility. M50I, L74M, and T97A are polymorphic mutations that alone did not appear to increase the risk of virological failure in persons receiving a CAB-containing regimen. Careful patient screening is required to prevent CAB from being used during active virus replication. Close virological monitoring is required to minimize CAB exposure to active replication to prevent the emergence of DRMs associated with cross-resistance to other INSTIs.

Impact of preexisting nucleos(t)ide reverse transcriptase inhibitor resistance on the effectiveness of bictegravir/emtricitabine/tenofovir alafenamide in treatment experience patients

INTRODUCTION

Few clinical trials and cohort studies have evaluated the efficacy of bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) in people with HIV (PWH) with preexisting M184V/I or other nucleos(t)ide reverse transcriptase inhibitor (NRTI) resistance-associated mutations (RAMs). Real-world data are also scarce.

METHODS

Retrospective review of treatment-experienced patients who started B/F/TAF in a cohort of PWH. HIV-RNA less than 50 copies/ml was analyzed at 48 weeks in an intention-to-treat (ITT) analysis (missing=failure) and per protocol analysis (patients with missing data or changes for reasons other than virological failure were excluded). Results were compared in patients with and without previous NRTI-RAMs.

RESULTS

Five hundred and six PWH were included (16.2% women). Median age and time with HIV infection were 52.3 and 18.9 years, respectively. At baseline, viral load was less than 50 copies/ml in 440 patients (86.6%). Overall, 69 (13.6%) participants had documented preexisting NRTI-RAMs: 57 (11.2%) M184V/I and 30 (5.9%) tenofovir RAMs. In the ITT analysis, 83% (420/506) had HIV-RNA less than 50 copies/ml [82.2% (359/437) and 88.4% (61/69) in persons without and with NRTI-RAMs, respectively ( P  = 0.2)]. In the per protocol analysis 94.2% (420/445) had HIV-RNA less than 50 copies/ml [94.4% (359/380) vs. 93.8% (61/65); P  = 0.2]. A total of 61 participants were excluded from the per protocol analysis (23 missing data, 19 discontinued B/F/TAF because of toxicity, 13 for other reasons, and 6 died).

CONCLUSION

Switching to B/F/TAF is well tolerated and effective in the real-world setting, even in patients with preexisting NRTI RAMs, such as M184V and RAMs conferring resistance to tenofovir. These results confirm the robustness of this combination.

Emergent dolutegravir resistance in integrase-naïve, treatment experienced patients from Zimbabwe

We report two cases of dolutegravir (DTG) resistance in highly treatment experienced patients. Monitoring for treatment failure and adherence support is important in highly treatment experienced patients taking DTG.

WHAT THIS STUDY ADDS

Dolutegravir is the mainstay of HIV treatment programmes and emergence of drug resistance to DTG is of public health relevance.

Low-level viraemia despite emergence of dolutegravir-resistant variants

No abstract available.

Once-daily dolutegravir-based antiretroviral therapy in infants and children living with HIV from age 4 weeks: results from the below 14 kg cohort in the randomised ODYSSEY trial

BACKGROUND

Young children living with HIV have few treatment options. We aimed to assess the efficacy and safety of dolutegravir-based antiretroviral therapy (ART) in children weighing between 3 kg and less than 14 kg.

METHODS

ODYSSEY is an open-label, randomised, non-inferiority trial (10% margin) comparing dolutegravir-based ART with standard of care and comprises two cohorts (children weighing ≥14 kg and <14 kg). Children weighing less than 14 kg starting first-line or second-line ART were enrolled in seven HIV treatment centres in South Africa, Uganda, and Zimbabwe. Randomisation, which was computer generated by the trial statistician, was stratified by first-line or second-line ART and three weight bands. Dispersible 5 mg dolutegravir was dosed according to WHO weight bands. The primary outcome was the Kaplan-Meier estimated proportion of children with virological or clinical failure by 96 weeks, defined as: confirmed viral load of at least 400 copies per mL after week 36; absence of virological suppression by 24 weeks followed by a switch to second-line or third-line ART; all-cause death; or a new or recurrent WHO stage 4 or severe WHO stage 3 event. The primary outcome was assessed by intention to treat in all randomly assigned participants. A primary Bayesian analysis of the difference in the proportion of children meeting the primary outcome between treatment groups incorporated evidence from the higher weight cohort (≥14 kg) in a prior distribution. A frequentist analysis was also done of the lower weight cohort (<14 kg) alone. Safety analyses are presented for all randomly assigned children in this study (<14 kg cohort). ODYSSEY is registered with ClinicalTrials.gov, NCT02259127.

FINDINGS

Between July 5, 2018, and Aug 26, 2019, 85 children weighing less than 14 kg were randomly assigned to receive dolutegravir (n=42) or standard of care (n=43; 32 [74%] receiving protease inhibitor-based ART). Median age was 1·4 years (IQR 0·6-2·0) and median weight 8·1 kg (5·4-10·0). 72 (85%) children started first-line ART and 13 (15%) started second-line ART. Median follow-up was 124 weeks (112-137). By 96 weeks, treatment failure occurred in 12 children in the dolutegravir group (Kaplan-Meier estimated proportion 31%) versus 21 (48%) in the standard-of-care group. The Bayesian estimated difference in treatment failure (dolutegravir minus standard of care) was -10% (95% CI -19% to -2%; p=0·020), demonstrating superiority of dolutegravir. The frequentist estimated difference was -18% (-36% to 2%; p=0·057). 15 serious adverse events were reported in 11 (26%) children in the dolutegravir group, including two deaths, and 19 were reported in 11 (26%) children in the standard-of-care group, including four deaths (hazard ratio [HR] 1·08 [95% CI 0·47-2·49]; p=0·86). 36 adverse events of grade 3 or higher were reported in 19 (45%) children in the dolutegravir group, versus 34 events in 21 (49%) children in the standard-of-care group (HR 0·93 [0·50-1·74]; p=0·83). No events were considered related to dolutegravir.

INTERPRETATION

Dolutegravir-based ART was superior to standard of care (mainly protease inhibitor-based) with a lower risk of treatment failure in infants and young children, providing support for global dispersible dolutegravir roll-out for younger children and allowing alignment of adult and paediatric treatment.

FUNDING

Paediatric European Network for Treatment of AIDS Foundation, ViiV Healthcare, UK Medical Research Council.