Effectiveness of dolutegravir-based regimens as either first-line or switch antiretroviral therapy: data from the Icona cohort

Introduction: Concerns about dolutegravir (DTG) tolerability in the real-life setting have recently arisen. We aimed to estimate the risk of treatment discontinuation and virological failure of DTG-based regimens from a large cohort of HIV-infected individuals. Methods: We performed a multicentre, observational study including all antiretroviral therapy (ART)-naïve and virologically suppressed treatment-experienced (TE) patients from the Icona (Italian Cohort Naïve Antiretrovirals) cohort who started, for the first time, a DTG-based regimen from January 2015 to December 2017. We estimated the cumulative risk of DTG discontinuation regardless of the reason and for toxicity, and of virological failure using Kaplan–Meier curves. We used Cox regression model to investigate predictors of DTG discontinuation. Results: About 1679 individuals (932 ART-naïve, 747 TE) were included. The one- and two-year probabilities (95% CI) of DTG discontinuation were 6.7% (4.9 to 8.4) and 11.5% (8.7 to 14.3) for ART-naïve and 6.6% (4.6 to 8.6) and 7.6% (5.4 to 9.8) for TE subjects. In both ART-naïve and TE patients, discontinuations of DTG were mainly driven by toxicity with an estimated risk (95% CI) of 4.0% (2.6 to 5.4) and 2.5% (1.3 to 3.6) by one year and 5.6% (3.8 to 7.5) and 4.0% (2.4 to 5.6) by two years respectively. Neuropsychiatric events were the main reason for stopping DTG in both ART-naïve (2.1%) and TE (1.7%) patients. In ART-naïve, a concomitant AIDS diagnosis predicted the risk of discontinuing DTG for any reason (adjusted relative hazard (aRH) = 3.38, p = 0.001), whereas starting DTG in combination with abacavir (ABC) was associated with a higher risk of discontinuing because of toxicity (aRH = 3.30, p = 0.009). TE patients starting a DTG-based dual therapy compared to a triple therapy had a lower risk of discontinuation for any reason (adjusted hazard ratio (aHR) = 2.50, p = 0.037 for ABC-based triple-therapies, aHR = 3.56, p = 0.012 for tenofovir-based) and for toxicity (aHR = 5.26, p = 0.030 for ABC-based, aHR = 6.60, p = 0.024 for tenofovir-based). The one- and two-year probabilities (95% CI) of virological failure were 1.2% (0.3 to 2.0) and 4.6% (2.7 to 6.5) in the ART naïve group and 2.2% (1.0 to 3.3) and 2.9% (1.5 to 4.3) in the TE group. Conclusions: In this large cohort, DTG showed excellent efficacy and optimal tolerability both as first-line and switching ART. The low risk of treatment-limiting toxicities in ART-naïve as well as in treated individuals reassures on the use of DTG in everyday clinical practice

Binding of recombinant PrPc to human plasminogen: kinetic and thermodynamic study using a resonant mirror biosensor

Transmissible spongiform encephalopathies are a class of sporadic, genetic and transmissible neurodegenerative diseases that affect both humans and animals. Propagation of these diseases is thought to be due to the misfolding of a neuronal glyco-protein, PrP(c), into a pathological insoluble conformer, PrP(Sc). In earlier works, some serum components were identified as exclusive PrP(Sc)-interacting proteins (Fisher et al., Nature 2000;408:479), and thus those macromolecules were thought to represent a potential diagnostic endogenous factor discriminating between normal and pathological prion proteins. In contrast, in agreement with a recent work (Kornblatt et al., Biochem Biophys Res Commun 2003;305:518), in this paper we present a detailed thermodynamic and kinetic characterization of the interaction between recombinant bovine PrP(c 25-242) and the human serum component plasminogen, measured using a resonant mirror technique: our results reveal a high-affinity interaction between the two binding partners. For comparison, the complex obtained from the purified full-length PrP(c) and human plasminogen was also studied: both prion proteins (the recombinant bovine PrP(c 25-242) and the purified full-length PrP(c)) are able to bind human plasminogen. Both kinetic and thermodynamic parameters are affected by the modulation exerted by the H(+) ions in solution. Moreover, the analysis of binding, according to canonical linkage relationships, suggests the involvement of a His residue, consistent with the interaction between other serine (pro)enzymes and their ligands

Interplay between 20S proteasomes and prion proteins in scrapie disease.

Scrapie is a transmissible spongiform encephalopathy affecting the central nervous system in sheep. The key event in such neurodegeneration is the conversion of the normal prion protein (PrPC) into the pathological isoform (PrPSc). Misfolded prion proteins are normally degraded by the proteasome. This work, analyzing models of scrapie disease, describes the in vivo relationship between the proteasome and prions. We report that the disease is associated with an increase of proteasome functionality, most likely as a means of counteracting the increased levels of oxidative stress. Here, we show that prions coprecipitate with the 20S proteasome and that they colocalize within the same neuron, thus raising the possibility that PrP interacts with the proteasome in both normal and diseased brain, affecting substrate trafficking and proteasome functionality. This interaction, inducing proteasome activation, leads to different neuronal alterations and triggers apoptosis. Furthermore, testing the effects of isolated PrPC on purified 20S proteasomes, we obtain a concentration- and proteasome composition-dependent decrease in the complex activity. (C) 2009 Wiley-Liss, Inc

Automatic diagnosis of newly emerged heart failure from serial electrocardiography by repeated structuring & learning procedure

Heart failure (HF) diagnosis, typically visually performed by serial electrocardiography, may be supported by machine-learning approaches. Repeated structuring & learning procedure (RS & LP) is a constructive algorithm able to automatically create artificial neural networks (ANN); it relies on three parameters, namely maximal number of hidden layers (MNL), initializations (MNI) and confirmations (MNC), arbitrarily set by the user. The aim of this study is to evaluate RS & LP robustness to varying values of parameters and to identify an optimized combination of parameter values for HF diagnosis. To this aim, the Leiden University Medical Center HF data-base was used. The database is constituted by 129 serial ECG pairs acquired in patients who experienced myocardial infarction; 48 patients developed HF at follow-up (cases), while 81 remained clinically stable (controls). Overall, 15 ANNs were created by considering 13 serial ECG features as inputs (extracted from each serial ECG pair), 2 classes as outputs (cases/controls), and varying values of MNL (1, 2, 3, 4 and 10), MNI (50, 250, 500, 1000 and 1500) and MNC (2, 5, 10, 20 and 50). The area under the curve (AUC) of the receiver operating characteristic did not significantly vary with varying parameter values (P >= 0.09). The optimized combination of parameter values, identified as the one showing the highest AUC, was obtained for MNL = 3, MNI = 500 and MNC = 50 (AUC = 86 %; ANN structure: 3 hidden layers of 14, 14 and 13 neurons, respectively). Thus, RS & LP is robust, and the optimized ANN represents a potentially useful clinical tool for a reliable auto-matic HF diagnosis.Cardiolog

Effectiveness of dolutegravir-based vs boosted darunavir-based first-line 3-drug regimens in people with HIV with advanced disease: A trial emulation

Background: No randomized comparisons exist between dolutegravir (DTG) and boosted-darunavir (DRV/b) for people initiating treatment with advanced HIV. Methods: Antiretroviral therapy (ART)-naïve people with HIV (PWH) with CD4 < 200 cells/mm3 or AIDS who started a first-line three-drug regimen with DTG or DRV/b were included. The primary outcome was a composite endpoint of newly diagnosed AIDS, serious non-AIDS events (SNAE), death, virological failure (VF), or discontinuation of the anchor drug due to failure or toxicity. A marginal structural Cox regression model was used to estimate the effect of starting DTG vs DRV/b-based regimens. Results: A total of 1323 advanced ART-naïve PWH were included, 895 starting DTG and 428 DRV/b. The unweighted risks of the composite endpoint by 48 months were 21.1% (95% CI: 18.1; 24.1%) for DTG vs 37.9% (95% CI: 32.7; 43.2%) for DRV/b (P < 0.001). First-line treatment with DTG showed a lower risk of experiencing the composite endpoint than DRV/b (wHR of DTG vs DRV/b 0.47, 95% CI: 0.35; 0.64, P < 0.001). Conclusion: Under the stated assumptions, this analysis indicates that in ART-naïve PWH with advanced disease, ART initiation with DTG vs DRV/b-based regimens leads to a 50% reduction in the risk of AIDS/SNAE/death/VF/discontinuation. This observed difference is partly explained by discontinuation of the anchor drug

Does Syphilis Increase the Risk of HIV-RNA Elevation >200 Copies/mL in HIV-Positive Patients under Effective Antiretroviral Treatment? Data from the ICONA Cohort

Background:To assess the impact of syphilis infection on the risk of HIV-RNA elevation in people living with HIV (PLWH) with current HIV-RNA ≤50 copies/mL.Setting:The Italian Cohort Naive Antiretrovirals.Methods:All PLWH (2009-2020) under antiretroviral treatment with at least 2 consecutive HIV-RNA values ≤50 copies/mL before the date of syphilis diagnosis and at least 1 HIV-RNA determination after the syphilis event were enrolled. A control group of PLWH without syphilis was matched for mode of HIV transmission. Outcomes were defined using the first HIV-RNA measure in the time window ranging between -2 and +6 months of the diagnosis/index date. The primary outcome used a single value >200 copies/mL to define HIV-RNA elevation associated with risk of transmission. The association between syphilis infection and the protocol defined outcome was evaluated using logistic regression analysis.Results:Nine hundred twenty-six PLWH with a syphilis event were enrolled and matched with a random sample of 1370 PLWH without syphilis. Eighteen of the 926 (1.9%) with syphilis had ≥1 HIV-RNA >200 copies/mL in the window vs. 29/1370 (2.1%) of the not exposed (P = 0.77). In the multivariable analysis adjusted for age, year of diagnosis/index date, and clinical site, syphilis infection was not associated with the risk of HIV-RNA >200 copies/mL (adjusted odds ratio 0.81; 95% confidence interval 0.43-1.52, P = 0.508).Conclusions:We did not find any evidence for an association between syphilis infection and viral elevation >200 copies/mL

Effectiveness and predictors of treatment discontinuation of long-acting cabotegravir/rilpivirine in virologically suppressed people with HIV: real-life data from the Icona Cohort

Background: Phase 3 studies have shown long-acting (LA) cabotegravir/rilpivirine to be effective and tolerable as maintenance therapy in people with HIV (PWH). However, real-life data on their effectiveness are limited. Methods: All PWH enrolled in the Icona Cohort who started LA cabotegravir/rilpivirine with HIV-RNA < 50 copies/mL were included. Times to treatment discontinuation (TD) and to virological failure (VF50, two consecutive HIV-RNA >50 copies/mL or one >1000 copies/mL followed by ART switch) were estimated by the Kaplan–Meier method. Cox regression models, adjusted for age, sex and mode of HIV transmission and stratified by the centre, were employed. Results: Overall, 583 PWH started LA cabotegravir/rilpivirine. Six VF50 were observed, with a 1 year estimated cumulative probability of virological failure of 1.2% (95% CI, 0.5%–3.0%). Resistance-associated mutations for rilpivirine and cabotegravir were detected in 3/4 and 4/4 participants with VF50, respectively, for which the genotypic resistance test was performed. The 1 year cumulative probability of TD was 11.4% (95% CI, 8.6%–14.9%), mainly caused by toxicity/adverse events (73.2%). Multivariable analysis identified heterosexual intercourse and IV drug use as significant risk factors for TD compared with MSM. Conclusions: This analysis demonstrated the short-term effectiveness of cabotegravir/rilpivirine in a real-life setting showing minimal incidence of virological failure but a notable probability of discontinuation due to toxicity or adverse events

Switching to dual/monotherapy determines an increase in CD8+ in HIV-infected individuals: An observational cohort study

Background: The CD4/CD8 ratio has been associated with the risk of AIDS and non-AIDS events. We describe trends in immunological parameters in people who underwent a switch to monotherapy or dual therapy, compared to a control group remaining on triple antiretroviral therapy (ART). Methods: We included patients in Icona who started a three-drug combination ART regimen from an ART-naïve status and achieved a viral load ≤ 50 copies/mL; they were subsequently switched to another triple or to a mono or double regimen. Standard linear regression at fixed points in time (12-24 months after the switch) and linear mixed model analysis with random intercepts and slopes were used to compare CD4 and CD8 counts and their ratio over time according to regimen types (triple vs. dual and vs. mono). Results: A total of 1241 patients were included; 1073 switched to triple regimens, 104 to dual (72 with 1 nucleoside reverse transcriptase inhibitor (NRTI), 32 NRTI-sparing), and 64 to monotherapy. At 12 months after the switch, for the multivariable linear regression the mean change in the log10 CD4/CD8 ratio for patients on dual therapy was -0.03 (95% confidence interval (CI) -0.05, -0.0002), and the mean change in CD8 count was +99 (95% CI +12.1, +186.3), taking those on triple therapy as reference. In contrast, there was no evidence for a difference in CD4 count change. When using all counts, there was evidence for a significant difference in the slope of the ratio and CD8 count between people who were switched to triple (points/year change ratio = +0.056, CD8 = -25.7) and those to dual regimen (ratio = -0.029, CD8 = +110.4). Conclusions: We found an increase in CD8 lymphocytes in people who were switched to dual regimens compared to those who were switched to triple. Patients on monotherapy did not show significant differences. The long-term implications of this difference should be ascertained

Role of low-frequency integrase strand transfer inhibitor resistance mutations on virological outcomes in antiretroviral therapy-naïve individuals initiating second-generation integrase inhibitors

Objectives: This study investigated the role of low-frequency integrase strand transfer inhibitor (INSTI) resistance mutations, detectable by next-generation sequencing (NGS), at predicting virological rebound (VR) among people with HIV (PWH) starting second-generation INSTI-based first-line regimens. Methods: This case-control study compared PWH (retrieved from the ICONA cohort; www.icona.org) who experienced VR (cases) with those who maintained virological control (controls) under first-line regimens based on dolutegravir or bictegravir. NGS data obtained through the Illumina platform were interpreted using the HIVdb algorithm version 9.7. Major (MRM), accessory (ARM), and other (ORM) INSTI resistance mutations were analysed at 5%, 10%, and 20% NGS cut-offs, respectively. Conditional logistic regression was used to evaluate the association between INSTI resistance and risk of VR. Results: Among 266 PWH (90 cases, 176 controls), cases experienced VR with a median (interquartile range) viremia of 317 (93–6060) copies/mL after 15 (8–28) months from antiretroviral therapy start. The prevalence of MRM was low (NGS cut-off 5%, 10%, 20%: 1.9%, 0.8%, 0.4%, respectively), while it was moderate for ARM (7.5%, 7.1%, 6.4%) and high for ORM (50.0%, 44.7%, 42.1%). There was no evidence of a difference in prevalence of ≥1 MRM, ARM, or ORM between cases and controls. At 5% NGS cut-off, the prevalence of ≥2 ORM was higher in cases compared with controls. After adjusting for confounders, including HIV-1 subtype, ≥2 ORM detected as minority variants remained associated with VR risk. Conclusion: Our findings suggest that combinations of low-frequency ORM may increase the risk of VR in individuals starting dolutegravir or bictegravir-based regimens. Further studies are needed to better understand these findings