Arkaitz Imaz
Bellvitge University Hospital
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Publication
Featured researches published by Arkaitz Imaz.
Journal of Antimicrobial Chemotherapy | 2014
A Curran; Polyana Monteiro; Pere Domingo; Judit Villar; Arkaitz Imaz; Esteban Martínez; Irene Fernandez; Hernando Knobel; Daniel Podzamczer; José Antonio Iribarren; María Peñaranda; Manuel Crespo
OBJECTIVES Ritonavir-boosted protease inhibitor monotherapy (PIMT) is a maintenance strategy that prevents nucleoside reverse transcriptase inhibitor toxicity and reduces costs. Some trials compare PIMT with combined antiretroviral therapy, but restricted selection criteria and low sample size hamper data extrapolation to routine practice. Here, we analyse the effectiveness and safety of PIMT in clinical practice. METHODS This was a retrospective, observational, multicentre study. Adult HIV-1 patients receiving PIMT with darunavir or lopinavir were included. A Cox regression model identified independent predictors for virological failure (VF). RESULTS A total of 664 patients (435 on darunavir/ritonavir and 229 on lopinavir/ritonavir) [74% male, median age of 54 years, one-third with previous protease inhibitor VF, CD4 nadir 189 cells/mm(3) and 42% coinfected with hepatitis C virus (HCV)] were analysed. After a median follow-up of 16 months, 78% of patients (95% CI 74%-81%) remained free from therapeutic failure (TF) (change between ritonavir-boosted PIs not considered failure). At 12 months, by intention-to-treat analysis (change between ritonavir-boosted PIs equals failure), 83% of patients were free from TF (87% darunavir/ritonavir versus 77% lopinavir/ritonavir, P = 0.001). Regarding VF, 88% of patients maintained viral suppression at 12 months (93% darunavir/ritonavir versus 88% lopinavir/ritonavir, P = not significant). CD4 nadir <200 cells/mm(3) [hazard ratio (HR) 1.58, 95% CI 1.01-2.49] and undetectable viral load prior to PIMT <24 months (HR 1.86, 95% CI 1.20-2.91) were independent predictors for VF. Prior protease inhibitor failure, HCV coinfection and the protease inhibitor/ritonavir used were not associated with PIMT outcome. A total of 158 patients stopped PIMT, 6% due to adverse events. Two patients developed encephalitis. CONCLUSIONS PIMT effectiveness was consistent with data from clinical trials. Viral suppression duration prior to PIMT and CD4 cell count nadir were independent predictors for PIMT outcome.
Hiv Clinical Trials | 2009
José R. Santos; Josep M. Llibre; Elena Ferrer; Pere Domingo; Arkaitz Imaz; José Moltó; Raquel Martin-Iguacel; Carme Caum; Daniel Podzamczer; Bonaventura Clotet
Abstract Objective: To assess the Efficacy and safety of switching from HAART containing enfuvirtide to raltegravir as a simplification strategy in patients with viral suppression and intolerance to enfuvirtide. Methods: Thirty-six patients with sustained plasma HIV RNA levels <50 copies/mL for at least 3 months with injection site reactions and/or injection fatigue while receiving an enfuvirtide-containing optimized background regimen switched from enfuvirtide to raltegravir (400 mg bid). Results: Patientshad received enfuvirtide for a median of 96 weeks and had sustained HIV RNA <50 copies/ mL for a median of 95 weeks. One patient discontinued raltegravir due to the appearance of cutaneous rash (grade 2) unresponsive to antihistamines after 19 days of starting raltegravir. The remaining 35 patients were followed for 24 weeks and 18 of them for 48 weeks. All patients maintained virological suppression <50 copies/mL at Weeks 24 and 48. No patient had blips in their viral load after switching to raltegravir. There were no grade 3 or 4 adverse events related to raltegravir. Conclusions: A switch from enfuvirtide to raltegravir in virologically suppressed patients who are highly treatment-experienced maintained both virologic and immunologic efficacy up to 48 weeks
AIDS Research and Human Retroviruses | 2014
Arkaitz Imaz; Nuria Cayuela; Jordi Niubó; Juan Tiraboschi; Cristina Izquierdo; Carmen Cabellos; Daniel Podzamczer
Abstract Monotherapy with boosted protease inhibitors has emerged as an antiretroviral therapy simplification alternative for selected patients, endorsed by the results of some randomized clinical trials. However, there are some concerns about the efficacy of such a strategy in achieving successful viral suppression in those anatomic compartments or reservoirs in which antiretroviral drug penetration is lower, such as the central nervous system (CNS). Several studies have demonstrated better neurocognitive performance in patients receiving antiretroviral drugs with better cerebrospinal fluid (CSF) penetration. Nevertheless, cases of CSF viral escape accompanied by moderate or severe neurological symptoms have been reported with both standard triple therapy and boosted protease inhibitor (PI) monotherapy, and it is not well established whether ritonavir-boosted protease inhibitor (PI/r) monotherapy is associated with a higher risk of symptomatic CSF viral escape or not. Herein, we present a case of viral r...Monotherapy with boosted protease inhibitors has emerged as an antiretroviral therapy simplification alternative for selected patients, endorsed by the results of some randomized clinical trials. However, there are some concerns about the efficacy of such a strategy in achieving successful viral suppression in those anatomic compartments or reservoirs in which antiretroviral drug penetration is lower, such as the central nervous system (CNS). Several studies have demonstrated better neurocognitive performance in patients receiving antiretroviral drugs with better cerebrospinal fluid (CSF) penetration. Nevertheless, cases of CSF viral escape accompanied by moderate or severe neurological symptoms have been reported with both standard triple therapy and boosted protease inhibitor (PI) monotherapy, and it is not well established whether ritonavir-boosted protease inhibitor (PI/r) monotherapy is associated with a higher risk of symptomatic CSF viral escape or not. Herein, we present a case of viral rebound and resistance emergence exclusively in CSF associated with an unusual clinical manifestation of focal encephalitis in a patient with plasma HIV-1 RNA suppression while receiving lopinavir/ritonavir monotherapy. Clinical resolution and CSF viral suppression were observed after switching to a genotype-guided combined antiretroviral regimen with good CSF penetration.
Antiviral Therapy | 2012
Adrian Curran; Esteban Martínez; Daniel Podzamczer; Montserrat Lonca; Patricia Barragán; Manel Crespo; Falco; Vidal-Sicart S; Arkaitz Imaz; Martinez M; Josep M. Gatell; Esteban Ribera
BACKGROUND Fat distribution, bone mineral density (BMD) and mitochondrial DNA (mtDNA) may improve, in the long-term, after switching from nucleoside reverse transcriptase inhibitors (NRTIs) to fixed-dose abacavir (ABC)/lamivudine (3TC) or tenofovir (TDF)/emtricitabine (FTC). METHODS This was a prospective, randomized, open-label, multicentre substudy of the BICOMBO trial in which virologically suppressed patients had their NRTIs switched to ABC/3TC or TDF/FTC. Whole-body dual-energy X-ray absorptiometry (DXA) was used to measure limb, trunk and total body fat and total BMD. Lumbar and hip DXA scans were used to measure lumbar and hip BMD. Fat mass ratio (FMR; % trunk fat/% leg fat by whole-body DXA) was used to assess fat distribution. mtDNA was measured in peripheral blood mononuclear cells (PBMCs). Parameters of interest were measured at baseline, 48 and 96 weeks, and were compared between treatment groups. RESULTS Of 56 patients included, 45 (20 ABC/3TC and 25 TDF/FTC) completed the substudy. After 96 weeks, ABC/3TC (+756 g, +12.1%) and TDF/FTC (+337 g, +7.6%) led to non-significantly different increases in limb fat (P=0.60). By contrast, trunk fat showed a significant increase (P=0.04) with ABC/3TC (+1,184 g, +10.6%) relative to TDF/FTC (-370 g, -4.2%). Median (IQR) FMR remained unchanged with ABC/3TC (-0.01 [-0.16-0.06]; P=0.23), but it decreased significantly with TDF/FTC (-0.13 [-0.30-0.00]; P=0.007). Total BMD and mtDNA significantly increased after 96 weeks, without differences between groups. CONCLUSIONS Switching from NRTIs to either ABC/3TC or TDF/FTC led to similar increases in limb fat, BMD and PBMC mtDNA after 96 weeks.
Antiviral Therapy | 2014
Arkaitz Imaz; Josep M. Llibre; Jordi Navarro; Jordi Curto; Bonaventura Clotet; Manuel Crespo; Elena Ferrer; Maria Saumoy; Juan Tiraboschi; Oscar Murillo; Daniel Podzamczer
BACKGROUND There are no clinical trials in which the main objective is to compare the efficacy of efavirenz versus ritonavir-boosted protease inhibitor (PI/r)-based initial antiretroviral therapy (ART) in patients with high plasma HIV-1 RNA levels. This study aims to compare these regimens in this patient population in the setting of routine clinical practice. METHODS This was a multicentre, observational cohort study, including 596 consecutive treatment-naive patients with plasma HIV-1 RNA>100,000 copies/ml initiating efavirenz or PI/r-based ART between 2000 and 2010. The primary effectiveness end point was the percentage of patients with HIV-1 RNA<50 copies/ml at week 48 by intent-to-treat analysis. RESULTS Among a total of 596 patients, 57% initiated efavirenz and 43% PI/r-regimens (73% lopinavir and fosamprenavir [62% lopinavir, 11% fosamprenavir]). HIV-1 RNA suppression to <50 copies/ml at week 48 was higher in the efavirenz group (84% versus 74% [difference 10%, 95% CI 3.4%, 16.7%; P=0.002]). The percentage of virological failures was similar (efavirenz 4% versus PI/r 4%; P=0.686), but voluntary discontinuations and toxicity-related treatment changes were higher with PI/r (4% versus 1%; P=0.006 and 11% versus 6%; P=0.069, respectively). However, resistance selection at failure was higher in patients receiving efavirenz (89% versus 50%; P=0.203). Efavirenz was significantly more effective than lopinavir/r or fosamprenavir/r, whereas no significant differences were observed between efavirenz and darunavir/r or atazanavir/r. The high viral suppression in the efavirenz group was also evident in patients with very high viral loads (>500,000 copies/ml) and in those with low CD4(+) T-cell counts. CONCLUSIONS In routine clinical practice, the effectiveness of initial efavirenz-based regimens was at least similar to or even higher than various PI/r-based regimens in HIV-1-infected patients with plasma HIV-1 RNA>100,000 copies/ml.
Expert Review of Anti-infective Therapy | 2017
Arkaitz Imaz; Daniel Podzamczer
ABSTRACT Introduction: Tenofovir alafenamide (TAF) is a novel prodrug of the nucleotide analogue reverse-transcriptase inhibitor, tenofovir. TAF has been co-formulated with emtricitabine (FTC), elvitegravir (EVG) and the EVG metabolic enhancer, cobicistat (COBI) as a single-tablet regimen being the first TAF-containing antiretroviral combination available. Areas covered: This article summarizes the available information on the pharmacology of the novel compound TAF and overviews TAF/FTC/EVG/COBI use for HIV-1 infected patients, with specific focus on clinical efficacy and safety data. Information sources include peer-reviewed scientific literature, conference proceedings and publically available regulatory reports. Compared to tenofovir disoproxil fumarate, TAF results in higher concentrations of the active metabolite tenofovir diphosphate within lymphoid cells, whereas plasma tenofovir exposure is about 90% lower. The efficacy and safety of TAF/FTC/EVG/COBI in treatment-naïve HIV-infected patients has been assessed in phase-III randomized trials, showing non-inferior virological suppression in comparison with TDF/FTC/EVG/COBI, and significantly lower renal and bone toxicity. In addition, TAF/FTC/EVG/COBI has demonstrated efficacy and safety as a switching strategy in suppressed HIV-1 infected individuals, including those with mild or moderate renal impairment. Expert commentary: Approval of the single-tablet TAF/FTC/EVG/COBI regimen is an important advance in HIV therapy, as it is associated with very high efficacy and a better kidney and bone safety profile compared to TDF-containing regimens due to the incorporation of TAF.
PLOS ONE | 2016
Jesús Troya; Pablo Ryan; Esteban Ribera; Daniel Podzamczer; Víctor Hontañón; José Alberto Terrón; Vicente Boix; Santiago Moreno; Pilar Barrufet; Manuel Castaño; Ana Carrero; María José Galindo; Ignacio Suárez-Lozano; Hernando Knobel; Miguel Raffo; Javier Solís; María Yllescas; Herminia Esteban; Juan González-García; Juan Berenguer; Arkaitz Imaz
Objectives Based on data from clinical practice, we evaluated the effectiveness and safety of switching to abacavir/lamivudine plus rilpivirine (ABC/3TC+RPV) treatment in virologically suppressed HIV-1-infected patients. Methods We performed a multicenter, non-controlled, retrospective study of HIV-1-infected patients who switched treatment to ABC/3TC+RPV. Patients had an HIV-RNA <50 copies/mL for at least 24 weeks prior to changing treatments. The primary objective was HIV-1 RNA <50 copies/mL at week 48. Effectiveness was analyzed by intention-to-treat (ITT), missing = failure and on-treatment (OT) analyses. The secondary objectives analyzed were adverse effects changes in renal, hepatic or lipid profiles, changes in CD4+ cell count and treatment discontinuations. Results Of the 205 patients included, 75.6% were men and the median age was 49. At baseline, before switching to ABC/3TC+RPV, median time since HIV diagnosis was 13.1 years, median time with undetectable HIV-1 RNA was 6.2 years and median time of previous antiretroviral regimen was 3.1 years (48.3% patients were taking efavirenz and ABC/3TC was the most frequent backbone coformulation in 69.7% of patients). The main reasons for switching were drug toxicity/poor tolerability (60.5%) and simplification (20%). At week 48, the primary objective was achieved by 187 out of 205 (91.2%) patients by ITT analysis, and 187 out of 192 (97.4%) patients by OT analysis. The CD4+ lymphocyte count and CD4+ percentage increased significantly from baseline to week 48 by a median of 48 cells/μL (−50 to 189) and 1.2% (−1.3% to 4.1%), respectively, P<0.001. Thirty-eight adverse events (AE) were detected in 32 patients. Of these, 25 had no clear association with treatment. Three patients interrupted therapy due to AE. We observed a decrease in all lipid parameters, P<0.001, and a slight improvement in the glomerular filtration rate, P<0.01. Therapy was considered to have failed in 18 patients owing to virological failure (5 [2.4%]), toxicity/poor tolerability (4 [2%]), clinical decision (3 [1.5%]), loss to follow-up (3 [1.5%]), death (1 [0.5%]), and no clinical data (2 [1%]). Conclusions The results of this study confirms that ABC/3TC+RPV is an effective, safe, and cost-effective option for the treatment of patients with virologically stable HIV-1 infection.
Journal of the International AIDS Society | 2014
Juan Tiraboschi; Arkaitz Imaz; Elena Ferrer; Maria Saumoy; Nerea Rozas; Marga Maso; Antonia Vila; Jordi Niubó; Daniel Podzamczer
Plasma trough concentrations of lopinavir (LPV) given as LPV/r 800/200 mg once daily (OD) are reduced in comparison with 400/100 mg twice daily (BID). While OD dosage of LPV/r is sufficient to achieve viral suppression in plasma, data about drug penetration and viral suppression in central nervous system (CNS) is needed, mainly if LPVr is used as maintenance monotherapy strategy in selected patients. The objective of this study was to evaluate CSF HIV‐1 RNA and CSF LPV concentrations in patients receiving LPV/r monotherapy OD (LPVrMOD).
PLOS ONE | 2018
Juan Pasquau; Carmen Hidalgo-Tenorio; Maria Luisa Montes; Alberto Romero-Palacios; Jorge Vergas; Isabel Sanjoaquín; José Hernández-Quero; Koldo Aguirrebengoa; Francisco Orihuela; Arkaitz Imaz; María J. Ríos-Villegas; Juan A. Flores; María Carmen Fariñas; Pilar Vázquez; María José Galindo; Isabel García-Mercé; Fernando Lozano; Ignacio Santos; Samantha E. de Jesus; Coral García-Vallecillos
Trial design The QoLKAMON study evaluated quality of life, efficacy and treatment safety in HIV patients receiving lopinavir/ritonavir in monotherapy (MT) versus continuing combined antiretroviral triple treatment with a boosted protease inhibitor (TT). Methods This was a 24-week, open-label, multicentre study in virologically-suppressed HIV-infected participants (N = 225) with a 2:1 randomization: 146 patients who switched to MT were compared with 79 patients who remained on a TT regimen. The primary endpoint was change in patient-reported outcomes in quality of life as measured by the MOS-HIV and EQ-5D questionnaires. Secondary endpoints included treatment adherence, patient satisfaction, incidence of adverse events and differences in plasma HIV-1 RNA viral load (VL) and CD4 cell counts. Results Baseline quality of life, measured with the MOS-HIV score, was very good (overall score of 83 ± 10.5 in the MT arm and 82.3 ± 11.3 in the TT arm) and suffered no change during the study in any of the arms (at week 24, 83.5 ± 12.2 in MT arm and 81.9 ± 12.7 in TT arm), without statistically significant differences when compared. In regards to adherence to therapy and patient satisfaction, some aspects (number of doses forgotten in the last week and satisfaction of treatment measured with the CESTA score, dimension 1) improved significantly with MT. There were also no differences in the incidence and severity of adverse events, even though 22.8% of those in the MT arm switched their treatment when they were included in the study. Moreover, there was also no significant difference between the immunological and virological evolution of MT and TT. In the MT arm, the VL was always undetectable in 83% of patients (vs 90.7% in the TT arm) and there were only 6.7% of virological failures with VL > 50 copies/mL (vs 2.3% in the TT arm), without resistance mutations and with resuppression of VL after switching back to TT. Conclusions In a new clinical trial, monotherapy as a treatment simplification strategy in HIV-1 infected patients with sustained viral suppression has demonstrated quality of life, safety and efficacy profiles comparable to those of conventional triple therapy regimens.
Enfermedades Infecciosas Y Microbiologia Clinica | 2018
Josep M. Llibre; Elisa de Lazzari; Jean-Michel Molina; Sébastien Gallien; Juan González-García; Arkaitz Imaz; Daniel Podzamczer; Bonaventura Clotet; Pere Domingo; Josep M. Gatell
OBJECTIVE To evaluate the efficiency of single-tablet regimens (STR) and multiple-tablet regimens (MTR) with exactly the same or different components. METHODS A study was conducted on HIV-1-infected antiretroviral-naïve patients from 6 Spanish or French centers, who were started on treatment with STR-Atripla®, or the same components separately (MTR-SC), or a different MTR (MTR-Other). Effectiveness was measured as percentage of HIV-RNA <50copies/mL at 48 weeks (ITT). Efficiency was the ratio between costs (direct cost of antiretrovirals plus outpatient visits, hospital admissions, and resistance tests) and effectiveness. RESULTS The study included a total of 2773 patients (759 STR-Atripla®, 483 MTR-SC, and 1531 MTR-Other). Median age was 37 years, 15% were HCV co-infected, 27% had a CD4+ count <200cells/μL, and 30% had viral load ≥100.000copies/mL. The duration of the assigned treatment was longer for STR-Atripla® (P<.0001). Response rates (adjusted for CD4+ count, viral load, and clustered on hospitals) at 48 weeks were 76%, 74%, and 62%, respectively (P<.0001). Virological failure was more common in MTR patients (P=.0025), and interruptions due to intolerance with MTR-Other (P<.0001). Cost per responder at 48 weeks (efficiency) was €12,406 with STR-Atripla®, €11,034 with MTR-SC (0.89 [0.82, 0.99] times lower), and €18,353 (1.48 [1.38, 1.61] times higher) with MTR-Other. CONCLUSIONS STR-Atripla® and MTR-SC regimens showed similar effectiveness, but virological failure rate was lower with STR-Atripla. MTR-SC, considered less convenient, had a marginally better efficiency, mainly due to lower direct costs. MTR-Other regimens had both a worse effectiveness and efficiency. Similar efficiency analyses adjusting for baseline characteristics should be recommended for new STRs.