Ildefonso Pulido

Influence of the Toll-Like Receptor 9 1635A/G Polymorphism on the CD4 Count, HIV Viral Load, and Clinical Progression

Objective:To analyze the influence of single-nucleotide polymorphisms (SNPs) in TLR2 (1892A/C and 2258G/A), TLR4 (896A/G and 1196C/T), and TLR9 (1635A/G) genes on CD4 count, HIV viral load, and clinical progression in a cohort of naive HIV-infected patients. Methods:TLR2, TLR4, and TLR9 SNPs were analyzed in 369 naive HIV-infected patients by real-time polymerase chain reaction and melting curve technology. TLR2 1892C/A and TLR9 1635A/G SNPs were also analyzed in a non-HIV-infected population. Multivariate multiple regression analysis and Cox regression analyses were performed to assess the potential association between the SNPs and the end points. Results:TLR2 and TLR4 SNPs were not associated with the end points of the study. Regarding TLR9 1635A/G SNP, patients with the AA genotype showed statistically lower CD4 count (P = 0.003) and higher HIV viral load (P = 0.0018) compared with AG+GG genotypes at cohort entry. The multivariate analysis showed a significant association between the 1635AA genotype and both end points. Cox regression analysis showed that HIV clinical progression to clinical stage C and death due to AIDS-related events under antiretroviral therapy was earlier in patients with the 1635AA genotype (P = 0.035, P = 0.017, respectively). Conclusions:TLR9 1635A/G SNP might have a role in HIV clinical disease progression.

Correlation between the Trofile® test and virological response to a short-term maraviroc exposure in HIV-infected patients

OBJECTIVES The current validated assay to determine tropism of HIV variants is Trofile, which has some limitations. The aim of this work was to correlate the virological response to a short-term maraviroc exposure with Trofile. METHODS From 1 July 2008 to 1 March 2009, 34 consecutive HIV-infected patients with detectable viral load during the last 6 months began an 8 day exposure to maraviroc (MCT group); six HIV-infected patients without antiretroviral therapy received no treatment (control group). Plasma viral load was evaluated on days 0, 2, 5 and 8. Baseline Trofile was performed in MCT group patients. The maraviroc clinical test (MCT) was considered positive if viral load was undetectable (< 40 HIV-RNA copies/mL) or a reduction > or = 1 log(10) HIV-RNA copies/mL was achieved after 8 days of maraviroc exposure. RESULTS Global concordance between MCT and Trofile was 93.5%. In patients with R5 virus according to Trofile, MCT was positive in 19/20 (concordance 95%); in patients with dual/mixed virus, MCT was negative in 10/11 (concordance 90.9%). An additional phenotypic tropism assay was performed in patients with discordance between MCT and Trofile, being concordant with MCT in both cases. Three patients showed a non-reportable Trofile result, and all of them achieved undetectability after MCT. CONCLUSIONS A clinical approach like short-term maraviroc exposure could be an additional resource to genetic and phenotypic HIV tropism assays. This clinical approach shows high concordance with Trofile, and could allow patients with non-reportable results by Trofile to benefit from maraviroc therapy.

The TLR4 ASP299GLY polymorphism is a risk factor for active tuberculosis in Caucasian HIV-infected patients.

INTRODUCTION Tuberculosis (TB) is a pandemic infectious disease especially frequent in HIV-infected patients. Toll-like receptor (TLR) 4 has been described to play a main role in the innate immunity against TB. In fact, single nucleotide polymorphisms (SNPs) in TLRs may influence AIDS disease progression. The association between two particular SNPs in human TLR4 (Asp299Gly and Thr399Ile) and active TB has been studied in non-HIV Africans with contradictory results. However, studies focusing on the effect of these TLR4 SNPs in active TB within a Caucasian HIV population are lacking. OBJECTIVES To analyze the association between TLR4 Asp299Gly and Thr399Ile SNPs and active TB, in Caucasian Mediterranean HIV-infected individuals. METHODS 468 HIV-infected patients were analyzed. TLR4 genotyping was performed by real-time PCR and melting curve technology. RESULTS TB was diagnosed in 59 (12,6%) patients. In a bivariate analysis several variables resulted significantly associated with active TB; intravenous drugs use (OR= 2.2; 95% CI [1.2-3.8]), hepatitis C virus (HCV) co-infection (OR= 3.4; 95% CI [1.6-7.1]), CD4 count (p<0.001), HIV viral load (p=0.003), latent TB prophylaxis (OR= 0.3; 95% CI [0.1-0.5]), and TLR4 Asp299Gly (OR= 2.0; 95% CI [1.1-4.2]). No statistical association was found for the TLR4 Thr399Ile. After a multivariate analysis, HCV co-infection (OR= 3.8; 95% CI [2.2-6.5]), baseline CD4 count (OR= 0.996; 95% CI [0.994-0.998]), TLR4 Asp299Gly (OR= 2.57; 95% CI [1.18-5.61]) were independently associated with active TB and inversely with latent TB prophylaxis (OR= 0.24; 95% CI [0.01-0.60]). CONCLUSIONS We describe an independent association between TLR4 Asp299Gly SNP and active TB in Caucasian Mediterranean HIV-infected patients.

Effect of Maraviroc on HIV Disease Progression-Related Biomarkers

ABSTRACT The potential effect of blocking the CCR5 receptor on HIV disease progression biomarkers is not well understood. We showed that an 8-day maraviroc (MVC) monotherapy clinical test (MCT) can be used in selecting patients to receive MVC-containing combined antiretroviral therapy (cART). Using this MCT model, we assessed the effect of MVC on several HIV disease progression biomarkers during the MCT (MVC-specific effect) and following short-term (12-week) cART. We compared 45 patients on MVC monotherapy with a control group of 25 patients on MVC-sparing cART. We found that MVC did not modify any biomarkers in patients that had no virological response after the MCT. MVC-specific effects in patients with virological responses included increased CD8+ T-cell activation and senescence levels, preservation of an increase in soluble CD14 (sCD14), and a decrease in D dimer levels. After 12 weeks, MVC-containing cART increased CD8+ T-cell counts and preserved CD4+ T-cell senescence levels compared with MVC-sparing cART. Moreover, there was a decrease in sCD14 levels in patients that received MVC-containing cART. In conclusion, effects compatible with CD8+ T-cell redistribution in peripheral blood were observed after MVC therapy. However, MVC was associated with a favorable profile in HIV disease progression biomarkers only in patients with a virological response. These results support a potential clinical benefit of a therapy which includes MVC in HIV-infected patients.

IL28B Single-Nucleotide Polymorphism rs12979860 Is Associated With Spontaneous HIV Control in White Subjects

The single-nucleotide polymorphism (SNP) rs12979860 near the IL28B gene has been associated with the spontaneous clearance of hepatitis C virus. We sought to determine whether this SNP could be associated with the spontaneous control of human immunodeficiency virus (HIV) infection. We studied the prevalence of the IL28B CC genotype among 53 white HIV controllers, compared with the prevalence among 389 HIV-infected noncontrollers. We found that the IL28B CC genotype was independently associated with spontaneous HIV control (odds ratio [OR], 2.669; P = .017), as were female sex (OR, 7.077; P ≤ .001) and the presence of HLA-B57 and/or B27 (OR, 3.080; P = .017). This result supports the idea that common host mechanisms are involved in the spontaneous control of these 2 chronic infections.

Discordance rates between Trofile test and short-term virological response to maraviroc.

Enhanced sensitivity Trofile (ES-Trofile) is the most frequently used technique to assay HIV tropism. A clinical approach to predict CCR5-antagonists efficacy, based on the virological response to a short-term maraviroc exposure (Maraviroc Clinical Test, MCT), has been recently reported. We compared the results of ES-Trofile with MCT in 47 HIV-infected patients, and a global discordance around 15% was observed between the phenotypic method and the clinical approach. Discordance results were mainly found in patients with an ES-Trofile reported as dual/mixed. These provocative results might have important clinical implications and should be considered in order to accurately prescribe treatment with CCR5 antagonists.

T-cell changes after a short-term exposure to maraviroc in HIV-infected patients are related to antiviral activity

OBJECTIVES Analyze the short-term immunological effect directly attributable to MRV without interference of other drugs. METHODS MRV group included experienced HIV-infected patients undergoing an 8-day MRV monotherapy. A comparison population included naïve HIV-infected patients starting combined antiretroviral therapy (cART group). Absolute CD4(+) and CD8(+) T-cells and T-lymphocyte subsets were determined at day 0 and 8. RESULTS Fifty-nine patients who underwent MRV monotherapy and 28 naïve patients were analyzed. Forty-one patients in the MRV group experienced a significant viral load decrease (MRV positive subgroup). Virological response and CD4(+) T-cell change were comparable in the MRV positive and cART groups. CD8(+) T-cell increase in the MRV positive subgroup showed a trend toward superiority when compared with the cART group. T-lymphocyte subset changes showed a similar profile in the MRV positive and cART groups with a differential effect in the TemRA cells related to MRV. No immunological effect (absolute lymphocyte counts or subsets) was observed in patients without virological response to MRV. CONCLUSIONS MRV produced CD4(+) and CD8(+) T-cell gains related to antiviral activity and comparable or even superior in terms of CD8(+) T-cells to naïve patients starting cART. No immunological effect occurred in subjects without virological response to MRV.

Long-Term Immunovirogical Effect and Tolerability of a Maraviroc- Containing Regimen in Routine Clinical Practice

OBJECTIVES to analyze the long-term immunovirological effect and tolerability of a maraviroc-containing antiretroviral therapy in viraemic and pretreated HIV-infected patients with a high prevalence of hepatitis C virus (HCV) coinfection. METHODS forty-six R5 HIV-infected patients (48% HCV-coinfected) started a maraviroc-containing antiretroviral regimen, including patients with multidrug resistant virus and patients after first virologic failure. A retrospective study was performed, analysing percentage of patients with undetectable viral load, mean CD4+ gain, liver enzymes, clinical events and treatment modification up to week 48. RESULTS Raltegravir plus a boosted protease inhibitor was combined with maraviroc in 65.2% of the patients (mainly patients with multidrug resistant virus), while the coformulation lamivudine/abacavir was combined with maraviroc in 26.1% (all of them patients after first virologic failure). After 48 weeks on maraviroc-containing regimen, 96.3% of the patients had achieved undetectability and a mean CD4+ count increase of 151 cells/mm3 was observed. Liver enzymes did not increase along the follow up. One patient died after 24 weeks follow up due to heroin overdose. One patient developed a non-Hodgkin lymphoma after 36 weeks follow up, despite undetectable viral load and significant CD4+ increase was achieved (the only AIDS-defining event observed). Treatment modification was performed in 19.6% of the patients: 77.7% of them experienced a treatment simplification and only 1/46 suspended maraviroc. CONCLUSIONS maraviroc-containing regimen is long-term effective and well tolerated in HIV-infected patients in routine clinical practice and in different clinical scenarios.

Maraviroc Clinical Test (MCT) as an alternative tool to decide CCR5-antagonists prescription in naïve HIV-infected patients

Our aim was to analyze the virological response to a combined antiretroviral therapy started after Maraviroc Clinical Test (MCT) in naïve HIV-infected patients. Forty-one patients were exposed to MCT, based on an 8-day MVC monotherapy. If undetectability or a viral load reduction >1 log10 HIV-RNA copies/ml was achieved, a MVC-containing cART was prescribed. Forty patients showed a positive MCT; undetectability after 48weeks on cART was achieved in 34/41 (82.9%) patients. The result of MCT was compared with a genotypic tropism method and with Trofile®, showing 10.7% and 18.75% discordance rates, respectively. MCT is a reliable tool to decide CCR5-antagonists prescription, also in the naïve scenario where most patients show a virological response to MVC independently the tropism result reported by genotypic or phenotypic methods.

Patients on a combined antiretroviral therapy after maraviroc clinical test show no immunovirological impairment

The maraviroc clinical test (MCT) is a clinical approach to establish the indication of maraviroc treatment. In this study, we analysed the long-term outcome of patients receiving a combined antiretroviral therapy (cART) selected according to MCT results. Ninety-two consecutive HIV-infected patients underwent MCT. A virological response (<40 HIV-RNA copies/ml after 24 weeks) was observed in 76/92 patients (82.6%). These patients (n=76) were included in a time to treatment failure analysis; after a mean follow-up period of 88 weeks, treatment failure was confirmed in 14 patients (18.4%). Tropism switch during MCT was observed in 3/35 patients (8.6%); these patients experienced excellent long-term outcome on cART. In conclusion, MCT should be considered as an additional method before CCR5-antagonists prescription.