Marco Montano

Maraviroc as intensification strategy in HIV-1 positive patients with deficient immunological response: an Italian randomized clinical trial.

Background Immunological non-responders (INRs) lacked CD4 increase despite HIV-viremia suppression on HAART and had an increased risk of disease progression. We assessed immune reconstitution profile upon intensification with maraviroc in INRs. Methods We designed a multi-centric, randomized, parallel, open label, phase 4 superiority trial. We enrolled 97 patients on HAART with CD4+<200/µL and/or CD4+ recovery ≤25% and HIV-RNA<50 cp/mL. Patients were randomized 1:1 to HAART+maraviroc or continued HAART. CD4+ and CD8+ CD45+RA/RO, Ki67 expression and plasma IL-7 were quantified at W0, W12 and W48. Results By W48 both groups displayed a CD4 increase without a significant inter-group difference. A statistically significant change in CD8 favored patients in arm HAART+maraviroc versus HAART at W12 (p=.009) and W48 (p=.025). The CD4>200/µL and CD4>200/µL + CD4 gain ≥25% end-points were not satisfied at W12 (p=.24 and p=.619) nor at W48 (p=.076 and p=.236). Patients continuing HAART displayed no major changes in parameters of T-cell homeostasis and activation. Maraviroc-receiving patients experienced a significant rise in circulating IL-7 by W48 (p=.01), and a trend in temporary reduction in activated HLA-DR+CD38+CD4+ by W12 (p=.06) that was not maintained at W48. Conclusions Maraviroc intensification in INRs did not have a significant advantage in reconstituting CD4 T-cell pool, but did substantially expand CD8. It resulted in a low rate of treatment discontinuations. Trial Registration ClinicalTrials.gov NCT00884858 http://clinicaltrials.gov/show/NCT00884858

HIV-1 residual viremia and proviral DNA in patients with suppressed plasma viral load (<400 HIV-RNA cp/ml) during different antiretroviral regimens.

Low levels of plasma viremia (below 50 copies/ml of HIV-1 RNA) can be detected in the majority of HIV+ subjects successfully treated with HAART. Aim of our study was to evaluate the impact of different antiretroviral regimens on this residual viremia and on proviral HIV-1 DNA in HAART-treated subjects with plasma HIV RNA <400 cp/ml and no history of virological failure. To this purpose, a cross-sectional analysis of 319 HIV-positive patients on HAART with plasma HIV RNA <400 cp/ml was performed. Subjects had been on HAART for a median of 3.6 years: the current regimen included two nucleoside reverse transcriptase inhibitors (NRTIs) plus a protease inhibitor (PI) in 104 (32.6%) cases, of which 73 treated with a boosted PI; two NRTIs plus a non-NRTI (NNRTI) were prescribed in 166 (52.2%) cases, and NRTIs-only in 49 cases (15.4%). Patients treated with PI had the lowest nadir CD4 cell count (237+191 cells/microl) compared to patients treated with NNRTI (384+192 cells/microl) or NRTIs-only (387+222 cells/microl). Cell-associated HIV-1 DNA was measured in 231 subjects. Residual viremia was measured in 238 subjects with plasma HIV-1 RNA levels < 50 copies/ml. Multivariate analysis showed that the use of NNRTI was independently associated to low levels of residual viremia and high levels of HIV-1DNA, whereas the use of PI was independently associated to low levels of HIV-1 DNA. The better virological performance of NNRTI in terms of low residual viremia is consistent with specific literature data, whereas the greater impact of PI on the viral reservoirs is noteworthy and needs further investigations.

Therapeutic DNA Vaccination of Vertically HIV-Infected Children: Report of the First Pediatric Randomised Trial (PEDVAC)

Subjects Twenty vertically HIV-infected children, 6–16 years of age, with stable viral load control and CD4+ values above 400 cells/mm3. Intervention Ten subjects continued their ongoing antiretroviral treatment (ART, Group A) and 10 were immunized with a HIV-DNA vaccine in addition to their previous therapy (ART and vaccine, Group B). The genetic vaccine represented HIV-1 subtypes A, B and C, encoded Env, Rev, Gag and RT and had no additional adjuvant. Immunizations took place at weeks 0, 4 and 12, with a boosting dose at week 36. Monitoring was performed until week 60 and extended to week 96. Results Safety data showed good tolerance of the vaccine. Adherence to ART remained high and persistent during the study and did not differ significantly between controls and vaccinees. Neither group experienced either virological failure or a decline of CD4+ counts from baseline. Higher HIV-specific cellular immune responses were noted transiently to Gag but not to other components of the vaccine. Lymphoproliferative responses to a virion antigen HIV-1 MN were higher in the vaccinees than in the controls (p = 0.047), whereas differences in reactivity to clade-specific Gag p24, RT or Env did not reach significance. Compared to baseline, the percentage of HIV-specific CD8+ lymphocytes releasing perforin in the Group B was higher after the vaccination schedule had been completed (p = 0.031). No increased CD8+ perforin levels were observed in control Group A. Conclusions The present study demonstrates the feasibility, safety and moderate immunogenicity of genetic vaccination in vertically HIV-infected children, paving the way for amplified immunotherapeutic approaches in the pediatric population. Trial registration clinicaltrialsregister.eu _2007-002359-18 IT

High Prevalence of M184 Mutation among Patients with Viroimmunologic Discordant Responses to Highly Active Antiretroviral Therapy and Outcomes after Change of Therapy Guided by Genotypic Analysis

ABSTRACT Whether highly active antiretroviral therapy (HAART) should be modified in patients with persistent increases in CD4+ T cells despite detectable viral loads is an unresolved question. Forty-three heavily pretreated human immunodeficiency virus (HIV)-infected patients with virologic failure during HAART were studied before a change of therapy guided by genotypic analysis and during follow-up. Patients with an increase in CD4+ cell count (>100 cells/ml) over pre-HAART values were considered to be discordant patients (20 individuals), whereas patients with a lower increase or no increase in CD4+ cell count were considered failing patients (23 individuals). Based on univariate analysis, a high CD4+ cell count before antiretroviral treatment, homosexual behavior as a risk factor for HIV infection, reduced drug exposure to nonnucleoside reverse transcriptase inhibitors, low replicative capacity of HIV isolates, and more frequent detection of HIV isolates with a non-B subtype, an R5 biological phenotype, and M184V and T215Y/F mutations were factors associated with a discordant response to HAART. Based on multivariate analysis, only the M184V mutation remained significantly associated with a viroimmunologic discordant response (odds ratio, 25.48; 95% confidence interval, 1.43 to 453.93). No difference in lamivudine exposure was found between discordant (95%) and failing (91%) patients. Twelve months after the genotypic analysis-guided change of therapy, 3 discordant (15%) and 6 failing patients (26%) achieved undetectable viral loads (<50 copies/ml), whereas in patients with HIV RNA loads of >500 copies/ml, discordant responses were observed in 5 out of 15 discordant patients and in 4 out of 16 failing patients. A relationship between the M184V mutation and a viroimmunologic discordant response to HAART was found. After the genotypic analysis-driven change of therapy, similar rates of virologic suppression were detected in the two groups.

Nevirapine use, prolonged antiretroviral therapy and high CD4 nadir values are strongly correlated with undetectable HIV-DNA and -RNA levels and CD4 cell gain

OBJECTIVES To evaluate the correlations of the combination of undetectable HIV-DNA (<10 copies/10(6) peripheral blood mononuclear cells) and HIV-RNA (<1 copy/mL of plasma) levels and a CD4 cell count of >500 cells/mm(3) (defined as the treatment goal) in a group of 420 antiretroviral treatment (ART) responder patients. METHODS A cross-sectional, open-label, multicentre trial was conducted in a cohort of 420 HIV-infected ART-treated subjects with viral loads persistently <50 copies/mL for a median observation time of 28.8 months. HIV-DNA and residual viraemia values and demographic, virological and immunological data were collected for each subject. RESULTS Undetectable HIV-DNA was found in 16.6% (70/420) of patients and was significantly correlated with undetectable (<1 copy/mL) plasma viraemia (P = 0.0001). Higher CD4 cell count nadir (P < 0.001), a lower HIV-RNA viraemia at the start of treatment (P = 0.0016) and nevirapine use (P < 0.001) were correlated with an undetectable value of HIV-RNA. Twenty-six out of 420 patients (6.2%) reached the treatment goal. In multivariate analysis, higher nadir CD4 cell count (OR 3.86, 95% CI 1.47-10.16, P = 0.006), the duration of therapy (OR 1.07, 95% CI 1.02-1.12, P = 0.004) and the use of nevirapine (OR 2.59, 95% CI 1.07-6.28, P = 0.034) were independently related to this condition. CONCLUSIONS Only 6.2% of ART-responder patients presented the combination of three laboratory markers that identified them as full responders. These results indicate the high variability of the ART-responding population and lead us to suggest caution in the selection of patients for possible simplification regimens.

Prognostic factors of long-term CD4+ count-guided interruption of antiretroviral treatment

Aim of the study was to determine predictors of the duration of antiretroviral treatment interruption in patients infected with HIV. This pilot prospective, open‐label, multicenter trial comprised 62 HIV‐seropositive subjects who decided voluntarily to interrupt therapy after two or more years of successful HAART. The primary end‐point was the time to patients being free of therapy before reaching a CD4+ cell count ≤350/µl. Fifteen of 62 patients remained in treatment interruption for more than 180 days. Patients restarting therapy had higher HIV‐DNA levels (P = 0.05), were treated more frequently with NNRTI‐drugs (P = 0.02), had a shorter period of HAART (P = 0.046), and lower CD4+ cell counts after day 14 of interruption of treatment (P = 0.04). Multivariate regression analysis showed that less than 323 baseline proviral HIV‐DNA cp/106 PBMCs and more than 564 CD4 cells/µl at day 14 after interruption were associated independently with a reduced risk of restarting treatment (P = 0.041 and P = 0.012, respectively). A score based on CD4+ cell counts at nadir, at baseline, at week 2 of treatment interruption, and on baseline HIV‐DNA values can identify patients with a prolonged period free safely of treatment. J. Med. Virol. 81:481–487, 2009.

The PEDVAC trial: preliminary data from the first therapeutic DNA vaccination in HIV-infected children.

The PEDVAC study is the first trial designed to analyze safety and immunogenicity of a therapeutic vaccination with a multiclade multigene HIV DNA vaccine (HIVIS) in infected children. Twenty HIV-1 vertically infected children (6-16 years of age), on stable antiretroviral treatment for at least 6 months with HIV-1 RNA<50 copies/ml and stable CD4 counts (> 400 cells/mm³ or 25%) over 12 months of follow-up, were recruited into the study. Enrolled patients have been randomized into two arms: a control group of 10 children who continued previous antiretroviral treatment (HAART) (arm A) and a group of 10 children immunized intramuscularly with the HIVIS DNA vaccine in addition to previous HAART (arm B). Immunizations took place at week 0, 4, 12 and the boosting dose is planned at week 36. The 10 children in the vaccine group have received the first 3 priming doses of the HIVIS vaccine. Safety data showed good tolerance to the vaccination schedule. Mild cutaneous self-limeted reactions consisted of local irritation, usually itching or erythema +/- swelling at the injection site, were reported. No severe systemic adverse events have been observed. No vaccinated children had a decrease of CD4 T-cell counts from baseline. None experienced virological failure. Analysis of cellular immune responses was scheduled at week 0, 4, 12, 16, 20, 40, 60, 72 and 96 by standard lymphoproliferation assay, intracellular cytokine staining and cell-ELISA, a miniaturized assay to measure antigen-induced IFNγ secretion. Evaluation of these results is in progress and will provide key information on the status and changes of antigen specific immunity during HIV DNA immunization.

Inhibition of dual/mixed tropic HIV-1 isolates by CCR5-inhibitors in primary lymphocytes and macrophages.

Background Dual/mixed-tropic HIV-1 strains are predominant in a significant proportion of patients, though little information is available regarding their replication-capacity and susceptibility against CCR5-antagonists in-vitro. The aim of the study was to analyze the replication-capacity and susceptibility to maraviroc of HIV-1 clinical isolates with different tropism characteristics in primary monocyte-derived-macrophages (MDM), peripheral-blood-mononuclear-cells (PBMC), and CD4+T-lymphocytes. Methods Twenty-three HIV-1 isolates were phenotipically and genotipically characterized as R5, X4 or dual (discriminated as R5+/X4, R5/X4, R5/X4+). Phenotypic-tropism was evaluated by multiple-cycles-assay on U87MG-CD4+-CCR5+−/CXCR4+-expressing cells. Genotypic-tropism prediction was obtained using Geno2Pheno-algorithm (false-positive-rate [FPR] = 10%). Replication-capacity and susceptibility to maraviroc were investigated in human-primary MDM, PBMC and CD4+T-cells. AMD3100 was used as CXCR4-inhibitor. Infectivity of R5/Dual/X4-viruses in presence/absence of maraviroc was assessed also by total HIV-DNA, quantified by real-time polymerase-chain-reaction. Results Among 23 HIV-1 clinical isolates, phenotypic-tropism-assay distinguished 4, 17 and 2 viruses with R5-tropic, dual/mixed-, and X4-tropic characteristics, respectively. Overall, viruses defined as R5+/X4-tropic were found with the highest prevalence (10/23, 43.5%). The majority of isolates efficiently replicated in both PBMC and CD4+T-cells, regardless of their tropism, while MDM mainly sustained replication of R5- or R5+/X4-tropic isolates; strong correlation between viral-replication and genotypic-FPR-values was observed in MDM (rho = 0.710;p-value = 1.4e-4). In all primary cells, maraviroc inhibited viral-replication of isolates not only with pure R5- but also with dual/mixed tropism (mainly R5+/X4 and, to a lesser extent R5/X4 and R5/X4+). Finally, no main differences by comparing the total HIV-DNA with the p24-production in presence/absence of maraviroc were found. Conclusions Maraviroc is effective in-vitro against viruses with dual-characteristics in both MDM and lymphocytes, despite the potential X4-mediated escape. This suggests that the concept of HIV-entry through one of the two coreceptors “separately” may require revision, and that the use of CCR5-antagonists in patients with dual/mixed-tropic viruses may be a therapeutic-option that deserves further investigations in different clinical settings.

Switching of Inferred Tropism Caused by HIV during Interruption of Antiretroviral Therapy

ABSTRACT After interruption of highly active antiretroviral therapy, 15 out of 53 patients with the X4 HIV strain had a significantly larger decrease in CD4+ T cell count (P = 0.001) and shorter length of treatment interruption (P = 0.02) than patients with the R5 strain. At treatment resumption, HIV inferred tropism switched from the X4 strain to the R5 variant in 9 patients (60%). These patients had a prolonged length of treatment interruption compared to that of those who still carried the X4 strain.