Modulating the Impact of Critical Events in Early HIV Infection: Effect of ART Initiation and Alcohol Use (MERLIN)

Modulating the Impact of Critical Events in Early HIV Infection: Effect of ART Initiation and Alcohol Use

Modulating the Impact of Critical Events in Early HIV Infection: Effect of ART Initiation and Alcohol Use

University of California, San Francisco, University of Washington, Asociación Civil Impacta Salud y Educación, Peru, Université de Montréal, Seattle Children's Hospital, National Institute on Drug Abuse (NIDA)

The overall objective is to determine the influence of timing of ART initiation and alcohol consumption on HIV disease course. ART initiation immediately after HIV infection largely results in smaller HIV reservoir and lower HIV-associated systemic inflammation, which has been linked to non-AIDS morbidity and mortality. Immediate ART also reduces HIV-associated bacterial translocation and may prevent intestinal microbiome dysbiosis, that has been linked to increased systemic inflammation. Immediate intervention is not, however, generally feasible and more information is required about the consequences of starting ART at later time-points, but still early after acquisition. The study will be conducted in Lima, Peru, in a cohort of 180 MSM and transgender women (TW) with acute (Ab-, HIV RNA+) or recent (≤ 3 months) HIV infection. Alcohol use disorder (AUDIT score ≥8) is present in ~50% of HIV + participants in our cohort, four times higher than that seen among males in the general Peruvian population. Although the role of alcohol use in HIV pathogenesis and disease course remains unclear, some studies show a correlation with accelerated disease progression. The effects of alcohol resemble early post-infection changes in bacterial translocation and pro-inflammatory cytokines induced by HIV and their impact on HIV disease course before and after ART initiation remain unexplored. Specific Aim 1: To determine the relative long-term benefits of immediate vs. early vs. delayed ART initiation at 24 weeks after diagnosis. The investigators will study outcomes after 2 and 4 years in MSM and TW diagnosed with acute or recent HIV infection. Specific Aim 2: To determine the impact of alcohol use on the relative long-term benefits of immediate vs. early vs. delayed initiation of ART.

Specific Aims: Recent studies suggest that very early initiation of ART (prior to seroconversion) does not prevent the establishment of HIV reservoirs, which eventually expand when ART is discontinued. Early ART initiation is, however, associated with preservation of CD4+ T cells and lower levels of total HIV DNA and cell-associated RNA as well as preservation of gut Th17 cells, thereby averting a major driver of HIV-related immune activation and limiting the size of the HIV reservoir. When, by contrast, ART is initiated in Fiebig III (FIII) or later, many HIV-associated changes have already occurred, including seeding of HIV reservoirs, damage to GI mucosa, and initiation of inflammatory cascades. Since ART initiation within weeks of HIV acquisition is not a viable public health strategy, it is important to more completely understand the relative long-term benefits of initiating ART at very early times after infection (FI-II) as opposed to after a short (during FIII-V) or longer delay (at 24 weeks). Since the possibility that high-level alcohol use can mitigate the benefits of early ART is emerging as a potentially important public health issue, the investigators will evaluate the impact of time of ART initiation as well as alcohol use on HIV pathogenesis in Peruvian men who have sex with men (MSM) and TW, in whom high-level alcohol use is common. They will study outcomes after 2 and 4 years in MSM and TW diagnosed with acute (Ab-, HIV RNA+) or recent (≤3 months) HIV infection. Three groups based on time since estimated date of detectible HIV infection (EDDI) to ART initiation will be studied: a) EDDI-to-ART: ≤ 30 days b) EDDI-to-ART: 31-90 days and c) EDDI-to-ART: >90 days The overarching hypotheses are: 1. Initiation of ART soon after HIV infection will dampen perturbations of GI microbiota, reduce HIV-induced inflammatory changes, and decrease seeding of the reservoir. Initiation of ART within 30 days will have the greatest benefit. 2. Irrespective of the time of ART initiation, alcohol use will compound the negative effects of HIV. SPECIFIC AIM 1) To determine the relative long-term benefits of immediate vs. early vs. delayed initiation of ART. Initiation of ART within 30 days of infection, while theoretically appealing, is infeasible in clinical practice because antibody-based tests, used almost world-wide, are unable to diagnose very early infection. Six months of ART initiated shortly after seroconversion can improve many immune parameters, although not to the near normal level seen when ART is initiated earlier.. Longer-term follow-up of seropositive participants who started ART ~2-8 months after HIV acquisition compared to those initiating ART within 30 days is needed to see whether markers of inflammation and residual viral load might continue to improve after 6 months, decreasing the difference between the groups. Methods: the investigators will evaluate the 3 groups using specimens from equivalent times after ART initiation for a total of 4 years of ART, comparing viral load, CD4 counts, time to reach undetectable VL, the GI microbiota, and inflammatory markers. Specimens from uninfected and chronically infected subjects are available as controls for some outcomes. They will model the size and persistence of the viral reservoir across all ART-compliant study subjects, measuring total HIV DNA, integrated HIV DNA and multi-spliced HIV RNA via TILDA (Tat/Rev Induced Limiting Dilution Assay) assay. In a subset of individuals from each group, the proviral integration sites will be defined at ART initiation and after 2 and 4 years to assess the maintenance of the reservoir by proliferating CD4 cells. SPECIFIC AIM 2) To determine the impact of high-level alcohol use on the relative long-term benefits of immediate vs. early vs. delayed ART initiation. High-level alcohol use results in changes in the GI microbiome, increasing dysbiosis and gut permeability, and these changes are associated with up-regulation of inflammatory pathways.. Dysbiosis is present in many HIV-infected patients. Methods: Investigators will compare outcomes between subjects by their reported alcohol use or by assessing alcohol use blood biomarkers (Phosphatidylethanol; PEth) at specified timepoints.. Finally, among ART-adherent subjects with persistent viral suppression, the investigators will assess inflammatory markers and HIV reservoirs in those with and without high-level alcohol use at 2 and 4 years after ART initiation.

Total HIV DNA reservoir at baseline (ART Initiation) Baseline total HIV DNA was measured in CD4+ T cells isolated from PBMC collected at the ART Initiation visit. Total DNA was quantitated using polymerase chain reaction (PCR) with primers within HIV (5'-LTR and gag).

Decay of total HIV DNA was assessed in CD4+ T cells isolated from PBMC collected at 1, 2, 4, 8, 16, 24, 96 and 192 weeks (as available) from ART initiation (which occurred prior to enrollment into MERLIN). Total DNA was quantitated using polymerase chain reaction (PCR) with primers within HIV (5'-LTR and gag). The longitudinal decay in total HIV DNA was analyzed by use of a mixed-effects model from the time of ART initiation up to 192 weeks.

Baseline integrated HIV DNA was measured in CD4+ T cells isolated from PBMC collected at the ART Initiation visit. Integrated DNA was quantitated using polymerase chain reaction (PCR) with primers within HIV (3'-LTR) and host DNA (alu).

Decay of integrated HIV DNA was assessed in CD4+ T cells isolated from PBMC collected at 1, 2, 4, 8, 16, 24, 96 and 192 weeks (as available) from ART initiation (which occurred prior to enrollment into MERLIN).. Integrated DNA was quantitated using polymerase chain reaction (PCR) with primers within HIV (3'-LTR) and host DNA (alu). The longitudinal decay in integrated HIV DNA was analyzed by use of a mixed-effects model from the time of ART initiation up to 192 weeks.

Baseline HIV DNA by TILDA stimulation was measured in CD4+ T cells isolated from PBMC collected at the ART Initiation visit. The inducible HIV reservoir (TILDA stimulation) was quantitated using a tat/rev induced limiting dilution assay (TILDA). Cells with inducible HIV proviruses were assessed by quantifying the frequency of CD4+ cells producing multiply-spliced HIV RNA after in-vitro stimulation.

Decay of inducible HIV DNA proviruses (TILDA stimulation) was assessed in CD4+ T cells isolated from PBMC collected at 1, 2, 4, 8, 16, 24, 96 and 192 weeks (as available) from ART initiation (which occurred prior to enrollment into MERLIN). The inducible HIV reservoir (TILDS stimulation) was quantitated using a tat/rev induced limiting dilution assay (TILDA). Cells with inducible HIV proviruses were assessed by quantifying the frequency of CD4+ cells producing multiply-spliced HIV RNA after in-vitro stimulation. The longitudinal decay in the inducible HIV DNA reservoir was analyzed by use of a mixed-effects model from the time of ART initiation up to 192 weeks.

HIV DNA integration sites were measured for up to 4 years after initiation of ART (which occurred prior to enrollment in MERLIN). HIV DNA integration was assessed using CD4+ T cells isolated from PBMC at enrollment, ART initiation and 24, 96 and 192 weeks after ART initiation. HIV integration into the STAT5 and BACH2 genes was measured by assessing hybrid transcript structure (HIV LTR to BACH2 or STAT5 exon); hybrid transcript structure was confirmed by sequencing.

The GI microbiome will be assessed using 16S rRNA-based phylogenetic characterization of microbiome composition using stool specimens obtained before and after ART initiation.

Levels of inflammatory biomarkers measured in plasma by Meso Scale Discovery (MSD) and ELISA assays prior to infection and after viral load suppression.

High level alcohol use will be measured using self report (AUDIT Score and Quick Drinking Survey) and a blood biomarker (PEth). Alcohol use level will be included in multivariate analysis of GI Microbiome composition as well as a covariate in other analyses.

HIV viral load was measured in plasma at multiple timepoints beginning with the first visit after HIV diagnosis (which occurred prior to enrollment in MERLIN), using standard commercial viral load kits with a cut-off of 40 HIV RNA copies/mL. The log10 of HIV RNA copies/mL is reported. A value of 1.6 or less represent an undetectable log10 viral load (log10 <40 copies/mL).

Inclusion Criteria: Men who have sex with men or transgender women HIV-infected with prior participation in SABES study in Lima Peru OR Established HIV infection OR HIV uninfected Exclusion Criteria: counter-indication for use of study antiretroviral drugs

Massanella M, Ignacio RAB, Lama JR, Pagliuzza A, Dasgupta S, Alfaro R, Rios J, Ganoza C, Pinto-Santini D, Gilada T, Duerr A, Chomont N. Long-term effects of early antiretroviral initiation on HIV reservoir markers: a longitudinal analysis of the MERLIN clinical study. Lancet Microbe. 2021 May;2(5):e198-e209. doi: 10.1016/s2666-5247(21)00010-0. Epub 2021 Mar 23.