Clinical and Immunologic Outcomes After Immediate or Deferred Antiretroviral Therapy Initiation During Primary Human Immunodeficiency Virus Infection: The Sabes Randomized Clinical Study

Acute retroviral syndrome

PURPOSE OF REVIEW

To review the most important recent literature on the definition, epidemiology, clinical presentation, pathogenesis and treatment of the acute retroviral syndrome (ARS), a constellation of nonspecific symptoms and transient illness occuring in at least 50% of persons shortly after HIV acquisition. ARS is driven by initial rapid HIV viral replication and dissemination after acquisition, followed by immune activation and massive systemic inflammation. A more detailed understanding of ARS is important for the implementation of early detection efforts, treatment and public health strategies to control HIV.

RECENT FINDINGS

Recent research has provided deeper insights into ARS. Key findings include associations of ARS with heightened immune activation and elevated levels of IFNγ and multiple other cytokines, particularly IP-10, as well as with higher viral load and more severe CD4 + depletion during acute infection. These negative impacts can be mitigated by early antiretroviral therapy initiation and long-term outcomes are generally similar in treated individals with or without ARS.

SUMMARY

Current findings underscore the importance of early detection and intervention in ARS to mitigate long-term health impacts and inform the development of targeted therapeutic strategies.

Observational study of effects of HIV acquisition and antiretroviral treatment on biomarkers of systemic immune activation

To assess whether biomarkers of systemic inflammation are associated with HIV acquisition or with the timing of ART initiation ("immediate", at diagnosis, versus "deferred", at 24 weeks post-diagnosis) in men-who-have-sex-with-men (MSM) and transgender women, we conducted a retrospective study comparing inflammatory biomarkers in participants' specimens collected before infection and after ≥2 years of effective ART. We measured biomarkers in four longitudinally collected plasma, including two specimens collected from each participant before and two after HIV acquisition and confirmed ART-suppression. Biomarkers were quantified by enzyme-linked immuno-assay or Meso Scale Discovery. When evaluating systematic variation in these markers over time, we found that multiple biomarkers consistently varied across participants' two pre-infection or two post-ART-suppression specimens. Additionally, we compared changes in biomarkers after vs before HIV acquisition. Across 47 participants, the levels of C-reactive protein (CRP), monocyte chemo-attractant protein-1, tumor necrosis factor-α and interferon gamma-induced protein-10 significantly increased while leptin and lipopolysaccharide binding protein (LBP) significantly decreased following HIV infection. Randomization to deferred-ART initiation was associated with greater increases in CRP and no decrease in LBP. Acquisition of HIV appeared to induce systemic inflammation, with elevation of biomarkers previously associated with infections and cardiovascular disease. Initiation of ART during the early weeks of infection tempered the increase in pro-inflammatory biomarkers compared to delaying ART for ~24 weeks after HIV diagnosis. These findings provide insight into potential mediators by which immediate-ART initiation improves health outcomes, perhaps because immediate-ART limits the size of the HIV reservoir or limits immune dysregulation that in turn trigger systemic inflammation.

Implementation of REDCap mobile app in an oral HIV clinical study

BACKGROUND

In Peru, HIV cases are highly concentrated among men who have sex with men (MSM). Despite the availability of anti-retroviral therapy, people living with HIV (PWH) have higher levels of oral diseases. Alcohol use disorder (AUD) is significantly present among PWH. Our overarching goal was to generate foundational evidence on the association of AUD and oral health in MSM with HIV and enhance research capacity for future intersectional research on AUD, oral health and HIV. Our specific aim was to implement an on-site electronic data collection system through the use of a REDCap Mobile App in a low-middle income country (LMIC) setting.

METHODS

Five validated surveys were utilized to gather data on demographics, medical history, HIV status, alcohol use, HIV stigma, perceived oral health status, and dietary supplement use. These surveys were developed in REDCap and deployed with the REDCap Mobile App, which was installed on ten iPads across two medical HIV clinics in Lima, Peru. REDCap app as well as the protocol for data collection were calibrated with feedback from trial participants and clinical research staff to improve clinical efficiency and participant experience.

RESULTS

The mean age of participants (n = 398) was 35.94 ± 9.13y, of which 98.5% identified as male, and 85.7% identified as homosexual. 78.1% of participants binge drank, and 12.3% reported being heavy drinkers. After pilot testing, significant modifications to the structure and layout of the surveys were performed to improve efficiency and flow. The app was successfully deployed to replace cumbersome paper records and collected data was directly stored in a REDCap database.

CONCLUSIONS

The REDCap Mobile App was successfully used due to its ability to: (a) capture and store data offline, (b) timely translate between multiple languages on the mobile app interface, and (c) provide user-friendly interface with low associated costs and ample support.

TRIAL REGISTRATION

1R56DE029639-01.

Incidence of low-level viremia and its impact on virologic failure among people living with HIV who started an integrase strand transfer inhibitors: a longitudinal cohort study

BACKGROUND

Low-level viremia (LLV) has been identified as a potential precursor to virologic failure (VF), yet its clinical implications, particularly within the context of Integrase Strand Transfer Inhibitors (INSTIs)-based regimens, remain insufficiently explored. The study aimed to investigate the relationship between LLV and VF within ART-naïve patients on INSTIs-based regimens in China.

METHODS

A longitudinal cohort study was conducted with ART-naïve patients aged ≥ 18 years at Beijing Ditan Hospital, under the Chinese National Free Antiretroviral Treatment Program (NFATP). The LLV was defined as a viral load (VL) ranging from 50 to 199 copies/mL after six months of ART initiation, and VF as a VL ≥ 200 copies/mL. Sensitive analyses were also performed, defining LLV as 50-999 copies/mL and VF as exceeding 1000 copies/mL. Multivariate logistic regression, Kaplan-Meier (KM) curve, and Generalized Estimating Equation (GEE) models were used to evaluate the risk factors associated with LLV and VF events.

RESULTS

The study involved 830 ART-naïve patients, comprising 600 in the INSTIs group and 230 in the protease inhibitors (PIs) group. LLV events were observed in 10.4% of patients on PIs-based regimens and and 3.2% on INSTIs-based regimens (P < 0.001). INSTIs-based regimens demonstrated a protective effect against LLV events (aHR = 0.27, 95% CI 0.137-0.532). VF events occurred in 10.9% of patients on PIs-based regimens and 2.0% on INSTIs-based regimens, respectively (P < 0.001). The occurrence of LLV events significantly increased the risk of VF by 123.5% (95% CI 7.5%-364.4%), while the integrase inhibitors were associated with a 76.9% (95% CI 59.1%-86.9%) reduction in VF risk.

CONCLUSION

Our findings indicate that INSTIs-based regimens are critical protective factors against LLV and subsequent VF. These results underscore the importance of HIV viral load monitoring to ensuring effective treatment outcomes, highlighting the necessity for prompt and precise monitoring to refine HIV treatment methodologies.

Protocol for evaluating mechanistic pathways associated with HIV acquisition via nested Least Absolute Shrinkage and Selective Operator analysis

Statistical analysis to evaluate mechanistic pathways can be limited by non-causal associations as well as co-linearity of high-dimensional data. Here, we present a protocol evaluating statistical associations between multiple exposure variables (sociodemographic and behavioral), immune biomarkers, and HIV acquisition. We describe steps for study setup, combining Least Absolute Shrinkage and Selective Operator with the standard regression approach, and building nested models. This approach can determine to what extent associations between risks for exposure contributes to HIV acquisition with or without associated changes in immune activation. For complete details on the use and execution of this protocol, please refer to Bender Ignacio et al.1.

Observational study of effects of HIV Acquisition and Antiretroviral Treatment on Biomarkers of Systemic Immune Activation

Objective

Assess whether biomarkers of systemic inflammation are associated with HIV acquisition or with the timing of ART initiation ("immediate", at diagnosis, versus "deferred", at 24 weeks post-diagnosis) in men-who-have-sex-with-men (MSM) and transgender women.

Design

A retrospective study comparing inflammatory biomarkers in participants' specimens collected before and after ≥2 years of effective ART.

Methods

Inflammatory biomarkers were measured in four longitudinally collected plasma specimens, including two plasma specimens collected from each participant before and two after HIV acquisition and confirmed ART-suppression. Biomarkers were quantified by enzyme-linked immuno-assay or Meso Scale Discovery. Statistical measures compared intra-participant and between-group changes in biomarkers.

Results

Across 50 participants, the levels of C-reactive protein (CRP), monocyte chemo-attractant protein-1, tumor necrosis factor-α and interferon gamma-induced protein-10 significantly increased while leptin and lipopolysaccharide binding protein (LBP) significantly decreased following HIV infection. Randomization to deferred-ART initiation was associated with greater increases in CRP and no decreases in LBP. Multiple biomarkers varied significantly within participants' two pre-infection or two post-ART-suppression specimens.

Conclusions

Acquisition of HIV appeared to induce systemic inflammation, with elevation of biomarkers previously associated with infections and cardiovascular disease. Initiation of ART during the early weeks of infection tempered the increase in pro-inflammatory biomarkers compared to those who delayed ART for ~24 weeks after HIV diagnosis, perhaps because immediate-ART limited the size of the HIV reservoir or limited immune dysregulation. Some but not all biomarkers appeared sufficiently stable to assess intraparticipant changes over time. Given that pro-inflammatory biomarkers predict multiple co-morbidities, our findings suggest that immediate-ART initiation may improve health outcomes.

Acute retroviral syndrome is associated with lower CD4 + T cell nadir and delayed viral suppression, which are blunted by immediate antiretroviral therapy initiation

OBJECTIVES

To describe the prevalence of acute retroviral syndrome (ARS) and associated findings during primary HIV, and explore the relationship of ARS to clinical, virological, and immunological outcomes within a longitudinal screen, retest and treat study that minimized ascertainment bias.

DESIGN

We evaluated ARS symptoms and signs among 216 persons with acute and early incident HIV within the Sabes study of timing of antiretroviral therapy (ART) initiation during primary HIV in Peru.

METHODS

We evaluated patient reported symptoms and signs during primary HIV and used logistic regression and generalized linear models to evaluate associations with CD4 + and CD8 + T cell counts, HIV viral load, and a panel of 23 soluble markers of immune activation.

RESULTS

Sixty-one percent of participants had at least one ARS finding and 35% had at least 3. More ARS findings were reported in those enrolled within a month of estimated date of detectable infection (EDDI). Having more ARS signs/symptoms was associated with increased risk of CD4 + cell decrease below 350 cells/ml within the first 24 weeks, failure to suppress HIV viral load, and was most strongly associated with elevated IP-10. Immediate ART blunted effects on symptoms, CD4 + cell count and viral load, as associations were strongest in the arm that started ART after 24 weeks. Detrimental associations of ARS with CD4 + counts, and CD4 + /CD8 + ratio were not maintained at 2 or 4 years.

CONCLUSIONS

ARS has marked associations with short-term immunologic function and virologic suppression, which were mitigated in participants randomized to initiate ART immediately during primary infection.

Dynamic immune markers predict HIV acquisition and augment associations with sociobehavioral factors for HIV exposure

Prior studies attempting to link biomarkers of immune activation with risk of acquiring HIV have relied on cross sectional samples, most without proximity to HIV acquisition. We created a nested case-control study within the Sabes study in Peru, and assessed a panel of plasma immune biomarkers at enrollment and longitudinally, including within a month of diagnosis of primary HIV or matched timepoint in controls. We used machine learning to select biomarkers and sociobehavioral covariates predictive of HIV acquisition. Most biomarkers were indistinguishable between cases and controls one month before HIV diagnosis. However, levels differed between cases and controls at study entry, months to years earlier. Dynamic changes in IL-2, IL-7, IL-10, IP-10 and IL-12, rather than absolute levels, jointly predicted HIV risk when added to traditional risk factors, and there was modest effect modification of biomarkers on association between sociobehavioral risk factors and HIV acquisition.

Single-cell multiomics reveals persistence of HIV-1 in expanded cytotoxic T cell clones

Understanding the drivers and markers of clonally expanding HIV-1-infected CD4⁺ T cells is essential for HIV-1 eradication. We used single-cell ECCITE-seq, which captures surface protein expression, cellular transcriptome, HIV-1 RNA, and TCR sequences within the same single cell to track clonal expansion dynamics in longitudinally archived samples from six HIV-1-infected individuals (during viremia and after suppressive antiretroviral therapy) and two uninfected individuals, in unstimulated conditions and after CMV and HIV-1 antigen stimulation. Despite antiretroviral therapy, persistent antigen and TNF responses shaped T cell clonal expansion. HIV-1 resided in Th1-polarized, antigen-responding T cells expressing BCL2 and SERPINB9 that may resist cell death. HIV-1 RNA⁺ T cell clones were larger in clone size, established during viremia, persistent after viral suppression, and enriched in GZMB⁺ cytotoxic effector memory Th1 cells. Targeting HIV-1-infected cytotoxic CD4⁺ T cells and drivers of clonal expansion provides another direction for HIV-1 eradication.

Immune Activation in Primary Human Immunodeficiency Virus: Influence of Duration of Infection, Treatment, and Substance Use

Background

Primary human immunodeficiency virus (HIV) is characterized by dynamic changes in viral load and innate and adaptive immune responses; it is unclear the extent to which time from acquisition to antiretroviral therapy (ART) initiation and substance use impact these immunologic changes.

Methods

We studied plasma immune activation biomarkers, viral load, and CD4+ and CD8+ cell counts in participants from the Sabes primary infection study in Peru, who had been randomized to begin ART immediately after diagnosis vs 24 weeks later. We modeled influence of substance use and duration of HIV infection on biomarkers at baseline and over 24 weeks.

Results

Compared to participants enrolled >30 days after HIV acquisition, participants enrolled during acute infection (≤30 days) had higher mean interferon (IFN)-γ and IFN-α2a (1.7-fold and 3.8-fold interquartile range [IQR] higher, respectively). Participants enrolled >30 days after HIV acquisition had higher mean baseline CD8+ cell count (2.7 times the IQR). Alcohol use (positive phosphatidylethanol level) was associated with elevated IFN-γ, tumor necrosis factor alpha (TNF-α), and interleukin 12p70 (IL-12p70), and smoking was associated with higher macrophage inflammatory protein 1α, TNF-α, and IL-12p70. Most biomarkers declined more quickly in participants who initiated ART immediately; however, substance use and duration of HIV infection at enrollment had little influence on rate of decline.

Conclusions

IFN-γ and other biomarkers are elevated during early primary infection, when exposure to HIV antigens is high. Immune activation decreased most quickly in those who started ART during acute/early primary infection. Higher CD8+ cell counts and a trend toward higher soluble CD163 levels during the 30 days after acquisition suggest the onset of compensatory responses and immune exhaustion.

Virological and Immunological Outcomes of an Intensified Four-Drug versus a Standard Three-Drug Antiretroviral Regimen, Both Integrase Strand Transfer Inhibitor-Based, in Primary HIV Infection

The optimal therapeutic approach for primary HIV infection (PHI) is still debated. We aimed to compare the viroimmunological response to a four- versus a three-drug regimen, both INSTI-based, in patients with PHI. This was a monocentric, prospective, observational study including all patients diagnosed with PHI from December 2014 to April 2018. Antiretroviral therapy (ART) was started, before genotype resistance test results, with tenofovir/emtricitabine and either raltegravir plus boosted darunavir or dolutegravir. Cumulative probability of virological suppression [VS] (HIV-1 RNA< 40 cp/mL), low-level HIV-1 DNA [LL-HIVDNA] (HIV-1 DNA < 200 copies/106PBMC), and CD4/CD8 ratio ≥1 were estimated using Kaplan−Meier curves. Factors associated with the achievement of VS, LL-HIVDNA, and CD4/CD8 ≥ 1 were assessed by a Cox regression model. We enrolled 144 patients (95.8% male, median age 34 years): 110 (76%) started a four-drug-based therapy, and 34 (24%) a three-drug regimen. Both treatment groups showed a comparable high probability of achieving VS and a similar probability of reaching LL-HIVDNA and a CD4/CD8 ratio ≥1 after 48 weeks from ART initiation. Higher baseline HIV-1 RNA and HIV-1 DNA levels lowered the chance of VS, whereas a better preserved immunocompetence increased that chance. Not statistically significant factors associated with LL-HIVDNA achievement were found, whereas a higher baseline CD4/CD8 ratio predicted the achievement of immune recovery. In PHI patients, the rapid initiation of either an intensified four-drug or a standard three-drug INSTI-based regimen showed comparable responses in terms of VS, viral reservoir size, and immunological recovery.

The single-cell landscape of immunological responses of CD4+ T cells in HIV versus severe acute respiratory syndrome coronavirus 2

PURPOSE OF REVIEW

CD4 T cell loss is the hallmark of uncontrolled HIV-1 infection. Strikingly, CD4 T cell depletion is a strong indicator for disease severity in the recently emerged coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We reviewed recent single-cell immune profiling studies in HIV-1 infection and COVID-19 to provide critical insight in virus-induced immunopathogenesis.

RECENT FINDINGS

Cytokine dysregulation in HIV-1 leads to chronic inflammation, while severe SARS-CoV-2 infection induces cytokine release syndrome and increased mortality. HIV-1-specific CD4 T cells are dysfunctional, while SARS-CoV-2-specific CD4 T cells exhibit robust Th1 function and correlate with protective antibody responses. In HIV-1 infection, follicular helper T cells (TFH) are susceptible to HIV-1 infection and persist in immune-sanctuary sites in lymphoid tissues as an HIV-1 reservoir. In severe SARS-CoV-2 infection, TFH are absent in lymphoid tissues and are associated with diminished protective immunity. Advancement in HIV-1 DNA, RNA, and protein-based single-cell capture methods can overcome the rarity and heterogeneity of HIV-1-infected cells and identify mechanisms of HIV-1 persistence and clonal expansion dynamics.

SUMMARY

Single-cell immune profiling identifies a high-resolution picture of immune dysregulation in HIV-1 and SARS-CoV-2 infection and informs outcome prediction and therapeutic interventions.

Initiation of Antiretroviral Therapy during Primary HIV Infection: Effects on the Latent HIV Reservoir, Including on Analytic Treatment Interruptions

Antiretroviral therapy (ART) inhibits HIV replication but does not eradicate the latent reservoir. The previous research suggests that earlier ART initiation provides benefit on limiting reservoir size, but timing and extent of this effect remain unclear. Analytic treatment interruption (ATI) may be used to demonstrate HIV remission, but whether early ART also improves likelihood or duration of even temporary virologic remission is unclear. This review seeks to answer both questions. We performed a systematic review and analysis following Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines and included 21 interventional or observational studies with sufficient HIV reservoir outcomes. We also aggregated reservoir outcomes and transformed data into approximate measurements of total HIV DNA per million peripheral blood mononuclear cells and analyzed the correlation between timing of ART initiation and reservoir size. People living with HIV who initiate ART in primary infection maintain smaller reservoirs on suppressive ART than those who initiate treatment during chronic infection. The reduction of reservoir is most pronounced when ART is started within 2 weeks of HIV acquisition. Across studies, we found a moderately strong association between longer time to ART initiation and reservoir size, which was strongest when measured after 1 year on ART (Pearson's r = 0.69, p = 0.0003). After ATI, larger pre-ATI reservoir size predicts shorter time to viral rebound. Early ART may also facilitate long-term control of viremia. Although achieving sustained HIV remission will require further interventions, initiating ART very early in infection could limit the extent of the reservoir and also lead to post-ATI control in rare cases.