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Dive into the research topics where Valdilea G. Veloso is active.

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Featured researches published by Valdilea G. Veloso.


The New England Journal of Medicine | 2010

Preexposure Chemoprophylaxis for HIV Prevention in Men Who Have Sex with Men

Robert M. Grant; Javier R. Lama; Peter L. Anderson; Vanessa McMahan; Albert Liu; Lorena Vargas; Pedro Goicochea; Martin Casapia; Juan Vicente Guanira-Carranza; Maria Esther Ramirez-Cardich; Orlando Montoya-Herrera; Telmo Fernandez; Valdilea G. Veloso; Susan Buchbinder; Suwat Chariyalertsak; Mauro Schechter; Linda-Gail Bekker; Kenneth H. Mayer; Esper G. Kallas; K. Rivet Amico; Kathleen Mulligan; Lane R. Bushman; Robert J. Hance; Carmela Ganoza; Patricia Defechereux; Brian S. Postle; Furong Wang; J. Jeff McConnell; Jia-Hua Zheng; Jeanny Lee

BACKGROUND Antiretroviral chemoprophylaxis before exposure is a promising approach for the prevention of human immunodeficiency virus (HIV) acquisition. METHODS We randomly assigned 2499 HIV-seronegative men or transgender women who have sex with men to receive a combination of two oral antiretroviral drugs, emtricitabine and tenofovir disoproxil fumarate (FTC-TDF), or placebo once daily. All subjects received HIV testing, risk-reduction counseling, condoms, and management of sexually transmitted infections. RESULTS The study subjects were followed for 3324 person-years (median, 1.2 years; maximum, 2.8 years). Of these subjects, 10 were found to have been infected with HIV at enrollment, and 100 became infected during follow-up (36 in the FTC-TDF group and 64 in the placebo group), indicating a 44% reduction in the incidence of HIV (95% confidence interval, 15 to 63; P=0.005). In the FTC-TDF group, the study drug was detected in 22 of 43 of seronegative subjects (51%) and in 3 of 34 HIV-infected subjects (9%) (P<0.001). Nausea was reported more frequently during the first 4 weeks in the FTC-TDF group than in the placebo group (P<0.001). The two groups had similar rates of serious adverse events (P=0.57). CONCLUSIONS Oral FTC-TDF provided protection against the acquisition of HIV infection among the subjects. Detectable blood levels strongly correlated with the prophylactic effect. (Funded by the National Institutes of Health and the Bill and Melinda Gates Foundation; ClinicalTrials.gov number, NCT00458393.).


Lancet Infectious Diseases | 2014

Uptake of pre-exposure prophylaxis, sexual practices, and HIV incidence in men and transgender women who have sex with men: a cohort study

Robert M. Grant; Peter L. Anderson; Vanessa McMahan; Albert Liu; K. Rivet Amico; Megha Mehrotra; Sybil Hosek; Carlos Mosquera; Martin Casapia; Orlando Montoya; Susan Buchbinder; Valdilea G. Veloso; Kenneth H. Mayer; Suwat Chariyalertsak; Linda-Gail Bekker; Esper G. Kallas; Mauro Schechter; Juan V. Guanira; Lane R. Bushman; David N. Burns; James F. Rooney; David V. Glidden

BACKGROUND The effect of HIV pre-exposure prophylaxis (PrEP) depends on uptake, adherence, and sexual practices. We aimed to assess these factors in a cohort of HIV-negative people at risk of infection. METHODS In our cohort study, men and transgender women who have sex with men previously enrolled in PrEP trials (ATN 082, iPrEx, and US Safety Study) were enrolled in a 72 week open-label extension. We measured drug concentrations in plasma and dried blood spots in seroconverters and a random sample of seronegative participants. We assessed PrEP uptake, adherence, sexual practices, and HIV incidence. Statistical methods included Poisson models, comparison of proportions, and generalised estimating equations. FINDINGS We enrolled 1603 HIV-negative people, of whom 1225 (76%) received PrEP. Uptake was higher among those reporting condomless receptive anal intercourse (416/519 [81%] vs 809/1084 [75%], p=0·003) and having serological evidence of herpes (612/791 [77%] vs 613/812 [75%] p=0·03). Of those receiving PrEP, HIV incidence was 1·8 infections per 100 person-years, compared with 2·6 infections per 100 person-years in those who concurrently did not choose PrEP (HR 0·51, 95% CI 0·26-1·01, adjusted for sexual behaviours), and 3·9 infections per 100 person-years in the placebo group of the previous randomised phase (HR 0·49, 95% CI 0·31-0·77). Among those receiving PrEP, HIV incidence was 4·7 infections per 100 person-years if drug was not detected in dried blood spots, 2·3 infections per 100 person-years if drug concentrations suggested use of fewer than two tablets per week, 0·6 per 100 person-years for use of two to three tablets per week, and 0·0 per 100 person-years for use of four or more tablets per week (p<0·0001). PrEP drug concentrations were higher among people of older age, with more schooling, who reported non-condom receptive anal intercourse, who had more sexual partners, and who had a history of syphilis or herpes. INTERPRETATION PrEP uptake was high when made available free of charge by experienced providers. The effect of PrEP is increased by greater uptake and adherence during periods of higher risk. Drug concentrations in dried blood spots are strongly correlated with protective benefit. FUNDING US National Institutes of Health.


The New England Journal of Medicine | 2011

Timing of Antiretroviral Therapy for HIV-1 Infection and Tuberculosis

Diane V. Havlir; Michelle A. Kendall; Prudence Ive; Johnstone Kumwenda; Susan Swindells; Sarojini S. Qasba; Anne F. Luetkemeyer; Evelyn Hogg; James F. Rooney; Xingye Wu; Mina C. Hosseinipour; Umesh G. Lalloo; Valdilea G. Veloso; Fatuma F. Some; N. Kumarasamy; Nesri Padayatchi; Breno Santos; Stewart E. Reid; James Hakim; Lerato Mohapi; Peter Mugyenyi; Jorge Sanchez; Javier R. Lama; Jean W. Pape; Alejandro Sanchez; Aida Asmelash; Evans Moko; Fred Sawe; Janet Andersen; Ian Sanne

BACKGROUND Antiretroviral therapy (ART) is indicated during tuberculosis treatment in patients infected with human immunodeficiency virus type 1 (HIV-1), but the timing for the initiation of ART when tuberculosis is diagnosed in patients with various levels of immune compromise is not known. METHODS We conducted an open-label, randomized study comparing earlier ART (within 2 weeks after the initiation of treatment for tuberculosis) with later ART (between 8 and 12 weeks after the initiation of treatment for tuberculosis) in HIV-1 infected patients with CD4+ T-cell counts of less than 250 per cubic millimeter and suspected tuberculosis. The primary end point was the proportion of patients who survived and did not have a new (previously undiagnosed) acquired immunodeficiency syndrome (AIDS)-defining illness at 48 weeks. RESULTS A total of 809 patients with a median baseline CD4+ T-cell count of 77 per cubic millimeter and an HIV-1 RNA level of 5.43 log(10) copies per milliliter were enrolled. In the earlier-ART group, 12.9% of patients had a new AIDS-defining illness or died by 48 weeks, as compared with 16.1% in the later-ART group (95% confidence interval [CI], -1.8 to 8.1; P=0.45). Among patients with screening CD4+ T-cell counts of less than 50 per cubic millimeter, 15.5% of patients in the earlier-ART group versus 26.6% in the later-ART group had a new AIDS-defining illness or died (95% CI, 1.5 to 20.5; P=0.02). Tuberculosis-associated immune reconstitution inflammatory syndrome was more common with earlier ART than with later ART (11% vs. 5%, P=0.002). The rate of viral suppression at 48 weeks was 74% and did not differ between the groups (P=0.38). CONCLUSIONS Overall, earlier ART did not reduce the rate of new AIDS-defining illness and death, as compared with later ART. In persons with CD4+ T-cell counts of less than 50 per cubic millimeter, earlier ART was associated with a lower rate of new AIDS-defining illnesses and death. (Funded by the National Institutes of Health and others; ACTG A5221 ClinicalTrials.gov number, NCT00108862.).


Science Translational Medicine | 2012

Emtricitabine-Tenofovir Concentrations and Pre-Exposure Prophylaxis Efficacy in Men Who Have Sex with Men

Peter L. Anderson; David V. Glidden; Albert Liu; Susan Buchbinder; Javier R. Lama; Juan V. Guanira; Vanessa McMahan; Lane R. Bushman; Martin Casapia; Orlando Montoya-Herrera; Valdilea G. Veloso; Kenneth H. Mayer; Suwat Chariyalertsak; Mauro Schechter; Linda-Gail Bekker; Esper G. Kallas; Robert M. Grant

PrEP drug concentrations associated with ≥90% reduction in HIV acquisition in men who have sex with men are achieved with daily dosing. PrEParing to Stop HIV Acquisition Pre-exposure prophylaxis (PrEP) using the antiretroviral drugs emtricitabine (FTC) and tenofovir disoproxil fumarate (TDF) is a recently proven strategy for preventing HIV acquisition. These drugs require phosphorylation in mononuclear cells to the pharmacologically active triphosphate moieties, called emtricitabine-triphosphate (FTC-TP) and tenofovir-diphosphate (TFV-DP). The iPrEx study was a randomized placebo-controlled trial of daily oral doses of FTC-TDF as PrEP in HIV-negative men who have sex with men. Participants all received a comprehensive package of HIV prevention services. HIV infections were reduced by 44% overall in the FTC-TDF arm relative to placebo. HIV risk was reduced by more than 90% among those having detectable drug in blood, indicating that adherence was a powerful determinant of drug efficacy at preventing HIV acquisition. A new study by Anderson et al. estimates specific drug concentrations and adherence levels associated with protection from HIV-1 acquisition in the iPrEx trial. A regression analysis predicted that a TFV-DP concentration of 16 fmol/106 peripheral blood mononuclear cells (PBMCs) (95% confidence interval, 3 to 28) was associated with a 90% reduction in HIV acquisition relative to placebo in the iPrEx study. To determine the number of tablets required to achieve this drug concentration, TFV-DP concentrations from another study called STRAND were used to establish expected TFV-DP concentrations. TFV-DP was detected in the blood at all dosing levels in all participants with a median (interquartile range) TFV-DP concentration of 11 fmol/106 PBMCs (6 to 13) after two doses per week, 32 fmol/106 PBMCs (25 to 39) after four doses per week, and 42 fmol/106 PBMCs (31 to 47) after seven doses per week. When the iPrEx study’s regression model was used to analyze the STRAND TFV-DP concentrations, the predicted HIV risk reductions were 76, 96, and 99% for two, four, and seven doses per week, respectively. These findings suggest that PrEP using oral FTC-TDF tablets is a robust intervention for preventing HIV acquisition among men who have sex with men. Drug concentrations associated with protection from HIV-1 acquisition have not been determined. We evaluated drug concentrations among men who have sex with men in a substudy of the iPrEx trial (1). In this randomized placebo-controlled trial, daily oral doses of emtricitabine/tenofovir disoproxil fumarate were used as pre-exposure prophylaxis (PrEP) in men who have sex with men. Drug was detected less frequently in blood plasma and in viable cryopreserved peripheral blood mononuclear cells (PBMCs) in HIV-infected cases at the visit when HIV was first discovered compared with controls at the matched time point of the study (8% versus 44%; P < 0.001) and in the 90 days before that visit (11% versus 51%; P < 0.001). An intracellular concentration of the active form of tenofovir, tenofovir-diphosphate (TFV-DP), of 16 fmol per million PBMCs was associated with a 90% reduction in HIV acquisition relative to the placebo arm. Directly observed dosing in a separate study, the STRAND trial, yielded TFV-DP concentrations that, when analyzed according to the iPrEx model, corresponded to an HIV-1 risk reduction of 76% for two doses per week, 96% for four doses per week, and 99% for seven doses per week. Prophylactic benefits were observed over a range of doses and drug concentrations, suggesting ways to optimize PrEP regimens for this population.


Journal of Acquired Immune Deficiency Syndromes | 1998

Molecular epidemiology of HIV-1 in Brazil: high prevalence of HIV-1 subtype B and identification of an HIV-1 subtype D infection in the city of Rio de Janeiro Brazil.

Mariza G. Morgado; Monick Lindenmeyer Guimarães; Carmen B. G. Gripp; C. I. Costa; Ivan Neves; Valdilea G. Veloso; Maria Inês Linhares-carvalho; Luis R. Castello-branco; Francisco I. Bastos; Carla Kuiken; Euclides Ayres de Castilho; Bernardo Galvão-Castro; Vera Bongertz

HIV-1 genetic variability and the potential association with modes of transmission exposure categories gender and distribution over time were investigated in 1993-96 in 131 HIV-infected individuals from Rio de Janeiro Brazil. The study group included 28 homosexual and 15 bisexual men 55 heterosexuals 24 injecting drug users and 1 blood transfusion recipient. HIV-1 env subtyping by heteroduplex mobility assay identified 106 infections (80.9%) with subtype B 20 (15.3%) with subtype F and 1 (0.8%)--the first reported in Brazil--with subtype D. According to restriction fragment length polymorphism with fok 1 restriction enzyme 39 (37%) of the 106 subtype B samples had the GWGR motif at the tip of the V3 loop typically found in subtype B in Brazil. A previous study conducted in Sao Paulo Brazil suggested that subtype F could be related specifically to injecting drug use. The present study however found no significant associations between HIV-1 subtypes and exposure categories gender or mode of transmission. The long-lasting nature of the AIDS epidemic in Brazil may have favored the dispersion of the HIV-1 subtypes among the various exposure categories.


PLOS ONE | 2013

Changing Mortality Profile among HIV-Infected Patients in Rio de Janeiro, Brazil: Shifting from AIDS to Non-AIDS Related Conditions in the HAART Era

Beatriz Grinsztejn; Paula M. Luz; Antonio G. Pacheco; Desiree V. G. Santos; Luciane Velasque; Ronaldo I. Moreira; Maria Regina Cotrim Guimarães; Estevão Portela Nunes; Alberto S. Lemos; Sayonara Rocha Ribeiro; Dayse Pereira Campos; Marco Vitoria; Valdilea G. Veloso

Introduction We describe temporal trends in the mortality rates and factors associated with AIDS and non-AIDS related mortality at the Evandro Chagas Clinical Research Institute (IPEC), Oswaldo Cruz Foundation (FIOCRUZ). Methods Adult patients enrolling from 1986 through 2009 with a minimum follow up of 60 days were included. Vital status was exhaustively checked using patients’ medical charts, through active contact with individuals and family members and by linkage with the Rio de Janeiro Mortality database using a previously validated algorithm. The CoDe protocol was used to establish the cause of death. Extended Cox proportional hazards models were used for multivariate modeling. Results A total of 3530 individuals met the inclusion criteria, out of which 868 (24.6%) deceased; median follow up per patient was 3.9 years (interquartile range 1.7–9.2 years). The dramatic decrease in the overall mortality rates was driven by AIDS-related causes that decreased from 9.19 deaths/100PYs n 1986–1991 to 1.35/100PYs in 2007–2009. Non-AIDS related mortality rates remained stable overtime, at around 1 death/100PYs. Immunodeficiency significantly increased the hazard of both AIDS-related and non-AIDS-related causes of death, while HAART use was strongly associated with a lower hazard of death from either cause. Conclusions Our results confirm the remarkable decrease in AIDS-related mortality as the HIV epidemic evolved and alerts to the conditions not traditionally related to HIV/AIDS which are now becoming more frequent, needing careful monitoring.


AIDS | 2014

Changes in renal function associated with oral emtricitabine/tenofovir disoproxil fumarate use for HIV pre-exposure prophylaxis.

Marc M. Solomon; Javier R. Lama; David V. Glidden; Kathleen Mulligan; Vanessa McMahan; Albert Liu; Juan V. Guanira; Valdilea G. Veloso; Kenneth H. Mayer; Suwat Chariyalertsak; Mauro Schechter; Linda-Gail Bekker; Esper G. Kallas; David N. Burns; Robert M. Grant

Objective:Tenofovir disoproxil fumarate (TDF) pre-exposure prophylaxis decreases sexual acquisition of HIV infection. We sought to evaluate the renal safety of TDF in HIV-uninfected persons. Design and methods:The Iniciativa Profilaxis Pre-Exposición (iPrEx) study randomly assigned 2499 HIV-seronegative men and transgender women who have sex with men (MSM) to receive oral daily TDF coformulated with emtricitabine (FTC/TDF) or placebo. Serum creatinine and phosphorus during randomized treatment and after discontinuation were measured, and creatinine clearance (CrCl) was estimated by the Cockcroft–Gault equation. Indicators of proximal renal tubulopathy (fractional excretion of phosphorus and uric acid, urine protein, and glucose) were measured in a substudy. Results:There was a small but statistically significant decrease in CrCl from baseline in the active arm, compared to placebo, which was first observed at week 4 (mean change: −2.4 vs. −1.1 ml/min; P = 0.02), persisted through the last on-treatment visit (mean change: +0.3 vs. +1.8 ml/min; P = 0.02), and resolved after stopping pre-exposure prophylaxis (mean change: −0.1 vs. 0.0 ml/min; P = 0.83). The effect was confirmed when stratifying by drug detection. The effect of FTC/TDF on CrCl did not vary by race, age, or history of hypertension. There was no difference in serum phosphate trends between the treatment arms. In the substudy, two participants receiving placebo had indicators of tubulopathy. Conclusions:In HIV-seronegative MSM, randomization to FTC/TDF was associated with a very mild nonprogressive decrease in CrCl that was reversible and managed with routine serum creatinine monitoring.


Memorias Do Instituto Oswaldo Cruz | 2005

Human immunodeficiency virus type 1 (HIV-1) genotyping in Rio de Janeiro, Brazil: assessing subtype and drug-resistance associated mutations in HIV-1 infected individuals failing highly active antiretroviral therapy

José Carlos Couto-Fernandez; Carlos Silva-de-Jesus; Valdilea G. Veloso; M. Rachid; R. S. G. Gracie; S. L. Chequer-Fernandez; S. M. Oliveira; D. Arakaki-Sanchez; P. J. N. Chequer; Mariza G. Morgado

In order to assess the human immunodeficiency virus type 1 (HIV-1) drug resistance mutation profiles and evaluate the distribution of the genetic subtypes in the state of Rio de Janeiro, Brazil, blood samples from 547 HIV-1 infected patients failing antiretroviral (ARV) therapy, were collected during the years 2002 and 2003 to perform the viral resistance genotyping at the Renageno Laboratory from Rio de Janeiro (Oswaldo Cruz Foundation). Viral resistance genotyping was performed using ViroSeq Genotyping System (Celera Diagnostic-Abbott, US). The HIV-1 subtyping based on polymerase (pol) gene sequences (protease and reverse transcriptase-RT regions) was as follows: subtype B (91.2%), subtype F (4.9%), and B/F viral recombinant forms (3.3%). The subtype C was identified in two patients (0.4%) and the recombinant CRF_02/AG virus was found infecting one patient (0.2%). The HIV-1 genotyping profile associated to the reverse transcriptase inhibitors has shown a high frequency of the M184V mutation followed by the timidine-associated mutations. The K103N mutation was the most prevalent to the non-nucleoside RT inhibitor and the resistance associated to protease inhibitor showed the minor mutations L63P, L10F/R, and A71V as the more prevalent. A large proportion of subtype B was observed in HIV-1 treated patients from Rio de Janeiro. In addition, we have identified the circulation of drug-resistant HIV-1 subtype C and are presenting the first report of the occurrence of an African recombinant CRF_02/AG virus in Rio de Janeiro, Brazil. A clear association between HIV-1 subtypes and protease resistance mutations was observed in this study. The maintenance of resistance genotyping programs for HIV-1 failing patients is important to the management of ARV therapies and to attempt and monitor the HIV-1 subtype prevalence in Brazil.


Clinical Infectious Diseases | 2015

Effects of Emtricitabine/Tenofovir on Bone Mineral Density in HIV-Negative Persons in a Randomized, Double-Blind, Placebo-Controlled Trial

Kathleen Mulligan; David V. Glidden; Peter L. Anderson; Albert Liu; Vanessa McMahan; Pedro Gonzales; Maria Esther Ramirez-Cardich; Sirianong Namwongprom; Piotr Chodacki; Laura Maria C. Mendonça; Furong Wang; Javier R. Lama; Suwat Chariyalertsak; Juan V. Guanira; Susan Buchbinder; Linda-Gail Bekker; Mauro Schechter; Valdilea G. Veloso; Robert M. Grant

BACKGROUND Daily preexposure prophylaxis (PrEP) with oral emtricitabine and tenofovir disoproxil fumarate (FTC/TDF) decreases the risk of human immunodeficiency virus (HIV) acquisition. Initiation of TDF decreases bone mineral density (BMD) in HIV-infected people. We report the effect of FTC/TDF on BMD in HIV-seronegative men who have sex with men and in transgender women. METHODS Dual-energy X-ray absorptiometry was performed at baseline and 24-week intervals in a substudy of iPrEx, a randomized, double-blind, placebo-controlled trial of FTC/TDF PrEP. Plasma and intracellular tenofovir concentrations were measured in participants randomized to FTC/TDF. RESULTS In 498 participants (247 FTC/TDF, 251 placebo), BMD in those randomized to FTC/TDF decreased modestly but statistically significantly by 24 weeks in the spine (net difference, -0.91% [95% confidence interval {CI}, -1.44% to -.38%]; P = .001) and hip (-0.61% [95% CI, -.96% to -.27%], P = .001). Changes within each subsequent 24-week interval were not statistically significant. Changes in BMD by week 24 correlated inversely with intracellular tenofovir diphosphate (TFV-DP), which was detected in 53% of those randomized to FTC/TDF. Net BMD loss by week 24 in participants with TFV-DP levels indicative of consistent dosing averaged -1.42% ± 29% and -0.85% ± 19% in the spine and hip, respectively (P < .001 vs placebo). Spine BMD tended to rebound following discontinuation of FTC/TDF. There were no differences in fractures (P = .62) or incidence of low BMD. CONCLUSIONS In HIV-uninfected persons, FTC/TDF PrEP was associated with small but statistically significant decreases in BMD by week 24 that inversely correlated with TFV-DP, with more stable BMD thereafter. CLINICAL TRIALS REGISTRATION NCT00458393.


AIDS | 2009

Early mortality and cause of deaths in patients using HAART in Brazil and the United States.

Beatriz Grinsztejn; Valdilea G. Veloso; Ruth Khalili Friedman; Ronaldo I. Moreira; Paula M. Luz; Dayse Pereira Campos; José Henrique Pilotto; Sandra W. Cardoso; Jeanne C. Keruly; Richard D. Moore

Objective:To compare the early mortality pattern and causes of death among patients starting HAART in Brazil and the United States. Methods:We analyzed the combined data from two clinical cohorts followed at the Johns Hopkins AIDS Service in Baltimore, United States, and the Evandro Chagas Clinical Research Institute AIDS Clinic in Rio de Janeiro, Brazil. Participants included those who entered either cohort between 1999 and 2007 and were antiretroviral naive. Follow-up was at 1 year since HAART initiation. Cox proportional hazards regression analysis was used to assess the role of the city on the risk of death. Results:A total of 859 and 915 participants from Baltimore and Rio de Janeiro, respectively, were included. In Rio de Janeiro, 64.7% of deaths occurred within 90 days of HAART initiation; in Baltimore, 48.9% occurred between 180 and 365 days. AIDS-defining illness (61.8%) and non-AIDS-defining illness (55.6%) predominated as causes of death in Rio de Janeiro and Baltimore, respectively. Risk of death was similar in both cities (hazard ratio 1.04; P value = 0.95) after adjusting for CD4+ T cell count, age, sex, HIV risk group, prior AIDS-defining illness, and Pneumocystis jirovecii pneumonia and Mycobacterium avium prophylaxis. Individuals with CD4+ T cell count less than or equal to 50 cells/μl (hazard ratio 4.36; P = 0.001) or older (hazard ratio, 1.03; P = 0.03) were more likely to die. Conclusion:Although late HIV diagnosis is a problem both in developed and developing countries, differences in the timing and causes of deaths clearly indicate that, besides interventions for early HIV diagnosis, different strategies to curb early mortality need to be tailored in each country.

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Paula M. Luz

Oswaldo Cruz Foundation

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Esau Joao

University of California

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