Associations between integrase strand-transfer inhibitors and cardiovascular disease in people living with HIV: a multicentre prospective study from the RESPOND cohort consortium

BACKGROUND

Although associations between older antiretroviral drug classes and cardiovascular disease in people living with HIV are well described, there is a paucity of data regarding a possible association with integrase strand-transfer inhibitors (INSTIs). We investigated whether exposure to INSTIs was associated with an increased incidence of cardiovascular disease.

METHODS

RESPOND is a prospective, multicentre, collaboration study between 17 pre-existing European and Australian cohorts and includes more than 32 000 adults living with HIV in clinical care after Jan 1, 2012. Individuals were eligible for inclusion in these analyses if they were older than 18 years, had CD4 cell counts and HIV viral load measurements in the 12 months before or within 3 months after baseline (latest of cohort enrolment or Jan 1, 2012), and had no exposure to INSTIs before baseline. These individuals were subsequently followed up to the earliest of the first cardiovascular disease event (ie, myocardial infarction, stroke, or invasive cardiovascular procedure), last follow-up, or Dec 31, 2019. We used multivariable negative binomial regression to assess associations between cardiovascular disease and INSTI exposure (0 months [no exposure] vs >0 to 6 months, >6 to 12 months, >12 to 24 months, >24 to 36 months, and >36 months), adjusted for cardiovascular risk factors. RESPOND is registered with ClinicalTrials.gov, NCT04090151, and is ongoing.

FINDINGS

29 340 people living with HIV were included in these analyses, of whom 7478 (25·5%) were female, 21 818 (74·4%) were male, and 44 (<1%) were transgender, with a median age of 44·3 years (IQR 36·2-51·3) at baseline. As of Dec 31, 2019, 14 000 (47·7%) of 29 340 participants had been exposed to an INSTI. During a median follow-up of 6·16 years (IQR 3·87-7·52; 160 252 person-years), 748 (2·5%) individuals had a cardiovascular disease event (incidence rate of 4·67 events [95% CI 4·34-5·01] per 1000 person-years of follow-up). The crude cardiovascular disease incidence rate was 4·19 events (3·83-4·57) per 1000 person-years in those with no INSTI exposure, which increased to 8·46 events (6·58-10·71) per 1000 person-years in those with more than 0 months to 6 months of exposure, and gradually decreased with increasing length of exposure, until it decreased to similar levels of no exposure at more than 24 months of exposure (4·25 events [2·89-6·04] per 1000 person-years among those with >24 to 36 months of exposure). Compared with those with no INSTI exposure, the risk of cardiovascular disease was increased in the first 24 months of INSTI exposure and thereafter decreased to levels similar to those never exposed (>0 to 6 months of exposure: adjusted incidence rate ratio of 1·85 [1·44-2·39]; >6 to 12 months of exposure: 1·19 [0·84-1·68]; >12 to 24 months of exposure: 1·46 [1·13-1·88]; >24 to 36 months of exposure: 0·89 [0·62-1·29]; and >36 months of exposure: 0·96 [0·69-1·33]; p<0·0001).

INTERPRETATION

Although the potential for unmeasured confounding and channelling bias cannot fully be excluded, INSTIs initiation was associated with an early onset, excess incidence of cardiovascular disease in the first 2 years of exposure, after accounting for known cardiovascular disease risk factors. These early findings call for analyses in other large studies, and the potential underlying mechanisms explored further.

FUNDING

The CHU St Pierre Brussels HIV Cohort, The Austrian HIV Cohort Study, The Australian HIV Observational Database, The AIDS Therapy Evaluation in the Netherlands National Observational HIV cohort, The EuroSIDA cohort, The Frankfurt HIV Cohort Study, The Georgian National AIDS Health Information System, The Nice HIV Cohort, The ICONA Foundation, The Modena HIV Cohort, The PISCIS Cohort Study, The Swiss HIV Cohort Study, The Swedish InfCare HIV Cohort, The Royal Free HIV Cohort Study, The San Raffaele Scientific Institute, The University Hospital Bonn HIV Cohort and The University of Cologne HIV Cohorts, ViiV Healthcare, and Gilead Sciences.

Integrase strand transfer inhibitor use and cancer incidence in a large cohort setting

Background

Limited data exist examining the association between incident cancer and cumulative integrase inhibitor (INSTI) exposure.

Methods

Participants were followed from baseline (latest of local cohort enrollment or January 1, 2012) until the earliest of first cancer, final follow-up, or December 31, 2019. Negative binomial regression was used to assess associations between cancer incidence and time-updated cumulative INSTI exposure, lagged by 6 months.

Results

Of 29 340 individuals, 74% were male, 24% were antiretroviral treatment (ART)-naive, and median baseline age was 44 years (interquartile range [IQR], 36–51). Overall, 13 950 (48%) individuals started an INSTI during follow-up. During 160 657 person-years of follow-up ([PYFU] median 6.2; IQR, 3.9–7.5), there were 1078 cancers (incidence rate [IR] 6.7/1000 PYFU; 95% confidence interval [CI], 6.3–7.1). The commonest cancers were non-Hodgkin lymphoma (n = 113), lung cancer (112), Kaposi’s sarcoma (106), and anal cancer (103). After adjusting for potential confounders, there was no association between cancer risk and INSTI exposure (≤6 months vs no exposure IR ratio: 1.15 [95% CI, 0.89–1.49], >6–12 months; 0.97 [95% CI, 0.71–1.32], >12–24 months; 0.84 [95% CI, 0.64–1.11], >24–36 months; 1.10 [95% CI, 0.82–1.47], >36 months; 0.90 [95% CI, 0.65–1.26] [P = .60]). In ART-naive participants, cancer incidence decreased with increasing INSTI exposure, mainly driven by a decreasing incidence of acquired immune deficiency syndrome cancers; however, there was no association between INSTI exposure and cancer for those ART-experienced (interaction P < .0001).

Conclusions

Cancer incidence in each INSTI exposure group was similar, despite relatively wide CIs, providing reassuring early findings that increasing INSTI exposure is unlikely to be associated with an increased cancer risk, although longer follow-up is needed to confirm this finding.

Clinical outcomes of two-drug regimens vs. three-drug regimens in antiretroviral treatment-experienced people living with HIV

BACKGROUND

Limited data exist comparing clinical outcomes of two-drug regimens (2DRs) and three-drug regimens (3DRs) in people living with HIV.

METHODS

Antiretroviral treatment-experienced individuals in RESPOND switching to a new 2DR or 3DR from 1/1/12-1/10/18 were included. The incidence of clinical events (AIDS, non-AIDS cancer, cardiovascular disease, end-stage liver and renal disease, death) was compared between regimens using Poisson regression.

RESULTS

Of 9791 individuals included, 1088 (11.1%) started 2DRs and 8703 (88.9%) 3DRs. The most common 2DRs were dolutegravir plus lamivudine (22.8%) and raltegravir plus boosted darunavir (19.8%); the most common 3DR was dolutegravir plus 2 nucleoside reverse transcriptase inhibitors (46.9%). Individuals on 2DRs were older (median 52.6 years [interquartile range 46.7-59.0] vs 47.7 [39.7-54.3]), and a higher proportion had ≥1 comorbidity (81.6% vs 73.9%).There were 619 events during 27,159 person-years of follow-up (PYFU): 540 (incidence rate [IR] 22.5/1000 PYFU [95% CI 20.7-24.5]) on 3DRs, 79 (30.9/1000 PYFU [24.8-38.5]) on 2DRs. The most common events were death (7.5/1000 PYFU [95% CI 6.5-8.6]) and non-AIDS cancer (5.8/1000 PYFU [4.9-6.8]). After adjustment for baseline demographic and clinical characteristics, there was a similar incidence of events on both regimen types (2DRs vs 3DRs IR ratio: 0.92 [0.72-1.19]; p=0.53).

CONCLUSIONS

This is the first large, international cohort assessing clinical outcomes on 2DRs. After accounting for baseline characteristics, there was a similar incidence of events on 2DRs and 3DRs. 2DRs appear to be a viable treatment option with regard to clinical outcomes; further research on resistance barriers and long-term durability of 2DRs is needed.

Treatment outcomes of integrase inhibitors, boosted protease inhibitors and nonnucleoside reverse transcriptase inhibitors in antiretroviral-naïve persons starting treatment

OBJECTIVES

Although outcomes of antiretroviral therapy (ART) have been evaluated in randomized controlled trials, experiences from subpopulations defined by age, CD4 count or viral load (VL) in heterogeneous real-world settings are limited.

METHODS

The study design was an international multicohort collaboration. Logistic regression was used to compare virological and immunological outcomes at 12 ± 3 months after starting ART with an integrase strand transfer inhibitor (INSTI), contemporary nonnucleoside reverse transcriptase inhibitor (NNRTI) or boosted protease inhibitor (PI/b) with two nucleos(t)ides after 1 January 2012. The composite treatment outcome (cTO) defined success as VL < 200 HIV-1 RNA copies/mL with no regimen change and no AIDS/death events. Immunological success was defined as a CD4 count > 750 cells/μL or a 33% increase where the baseline CD4 count was ≥ 500 cells/μL. Poisson regression compared clinical failures (AIDS/death ≥ 14 days after starting ART). Interactions between ART class and age, CD4 count, and VL were determined for each endpoint.

RESULTS

Of 5198 ART-naïve persons in the International Cohort Consortium of Infectious Diseases (RESPOND), 45.4% started INSTIs, 26.0% PI/b and 28.7% NNRTIs; 880 (17.4%) were aged > 50 years, 2539 (49.4%) had CD4 counts < 350 cells/μL and 1891 (36.8%) had VL > 100 000 copies/mL. Differences in virological and immunological success and clinical failure among ART classes were similar across age groups (≤ 40, 40-50 and > 50 years), CD4 count categories (≤ 350 vs. > 350 cells/μL) and VL categories at ART initiation (≤ 100 000 vs. > 100 000 copies/mL), with all investigated interactions being nonsignificant (P > 0.05).

CONCLUSIONS

Differences among ART classes in virological, immunological and clinical outcomes in ART-naïve participants were consistent irrespective of age, immune suppression or VL at ART initiation. While confounding by indication cannot be excluded, this provides reassuring evidence that such subpopulations will equally benefit from contemporary ART.

An Indirect Comparison of Efficacy and Safety of Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Disoproxil Fumarate and Abacavir/Lamivudine + Dolutegravir in Initial Therapy

Objectives

The objective of this analysis is to perform an indirect comparison of elvitegravir, cobicistat, emtricitabine and tenofovir DF (E/C/F/TDF) to abacavir/lamivudine and dolutegravir (ABC/3TC + DTG) by using 2 trials evaluating each of these regimens in comparison to efavirenz, emtricitabine and tenofovir DF (EFV/FTC/TDF).

Methods

An indirect comparison was performed by using a generalization of Bucher's methodology to calculate risk differences. Two phase III clinical trials (GS-US-236-0102 and SINGLE—described above) were used.

Results

Results of the indirect comparison showed no statistically significant risk difference of the efficacy endpoint of achieving HIV RNA < 50 copies/mL between E/C/F/TDF and ABC/3TC + DTG for the ITT population at weeks 48, 96 and 144: respectively -3.7% (CI95% = [-10.8%; 3.4%]), -5.2% (CI95% = [-13.2%; 2.8%]) and -3.1% (CI_95% = [-12.0%; 5.7%]). There was no statistically significant differences in the risk difference for serious adverse events (5.7% (CI95% = [-2.2%; 12.3%])), drug related adverse event (2.7% (CI95% = [-7.0%;12.4%])), drug related serious adverse event (0.8% (CI95% = [-1.6%;3.2%])) and death (0.5% (CI95% = [-0.8%;1.8%])), respectively, between E/C/F/TDF and ABC/3TC + DTG. A significant difference was found for discontinuation due to adverse events with a higher rate for E/C/F/TDF (difference = 8.6% (CI95% = [3.3%; 13.9%])). There was also no statistically significant risk difference of the viral resistance of 1.2% (CI95% = [-1.2; 3.7]) between E/C/F/TDF and ABC/3TC + DTG at week 48, 1.7% at week 96 (CI95% = [-1.1; 4.5]) and 2.2% (CI95% = [-1.0; 5.4]) at week 144.