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Dive into the research topics where Ricardo Machado Xavier is active.

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Featured researches published by Ricardo Machado Xavier.


The New England Journal of Medicine | 2012

Randomized Trial of Tocilizumab in Systemic Juvenile Idiopathic Arthritis

Fabrizio De Benedetti; Hermine I. Brunner; Nicolino Ruperto; Andrew Kenwright; Stephen Wright; Inmaculada Calvo; Ruben Cuttica; Angelo Ravelli; Rayfel Schneider; Patricia Woo; Carine Wouters; Ricardo Machado Xavier; Lawrence S. Zemel; E. Baildam; Ruben Burgos-Vargas; Pavla Dolezalova; Stella Garay; Rosa Merino; R. Joos; Alexei A. Grom; Nico Wulffraat; Zbigniew Zuber; Daniel J. Lovell; Alberto Martini

BACKGROUND Systemic juvenile idiopathic arthritis (JIA) is the most severe subtype of JIA; treatment options are limited. Interleukin-6 plays a pathogenic role in systemic JIA. METHODS We randomly assigned 112 children, 2 to 17 years of age, with active systemic JIA (duration of ≥6 months and inadequate responses to nonsteroidal antiinflammatory drugs and glucocorticoids) to the anti-interleukin-6 receptor antibody tocilizumab (at a dose of 8 mg per kilogram of body weight if the weight was ≥30 kg or 12 mg per kilogram if the weight was <30 kg) or placebo given intravenously every 2 weeks during the 12-week, double-blind phase. Patients meeting the predefined criteria for nonresponse were offered open-label tocilizumab. All patients could enter an open-label extension. RESULTS At week 12, the primary end point (an absence of fever and an improvement of 30% or more on at least three of the six variables in the American College of Rheumatology [ACR] core set for JIA, with no more than one variable worsening by more than 30%) was met in significantly more patients in the tocilizumab group than in the placebo group (64 of 75 [85%] vs. 9 of 37 [24%], P<0.001). At week 52, 80% of the patients who received tocilizumab had at least 70% improvement with no fever, including 59% who had 90% improvement; in addition, 48% of the patients had no joints with active arthritis, and 52% had discontinued oral glucocorticoids. In the double-blind phase, 159 adverse events, including 60 infections (2 serious), occurred in the tocilizumab group, as compared with 38, including 15 infections, in the placebo group. In the double-blind and extension periods combined, 39 serious adverse events (0.25 per patient-year), including 18 serious infections (0.11 per patient-year), occurred in patients who received tocilizumab. Neutropenia developed in 19 patients (17 patients with grade 3 and 2 patients with grade 4), and 21 had aminotransferase levels that were more than 2.5 times the upper limit of the normal range. CONCLUSIONS Tocilizumab was efficacious in severe, persistent systemic JIA. Adverse events were common and included infection, neutropenia, and increased aminotransferase levels. (Funded by Hoffmann-La Roche; ClinicalTrials.gov number, NCT00642460.).


Clinical and Experimental Immunology | 2008

Redox signalling and the inflammatory response in rheumatoid arthritis

Lidiane Isabel Filippin; Rafael Vercelino; N. P. Marroni; Ricardo Machado Xavier

Reactive oxygen species (ROS) are produced mainly during oxidative phosphorylation and by activated phagocytic cells during oxidative burst. The excessive production of ROS can damage lipids, protein, membrane and nucleic acids. They also serve as important intracellular signalling that enhances the inflammatory response. Many studies have demonstrated a role of ROS in the pathogenesis of inflammatory chronic arthropathies, such as rheumatoid arthritis. It is known that ROS can function as a second messenger to activate nuclear factor kappa‐B, which orchestrates the expression of a spectrum of genes involved in the inflammatory response. Therefore, an understanding of the complex interactions between these pathways might be useful for the development of novel therapeutic strategies for rheumatoid arthritis.


Arthritis Care and Research | 2009

Association of concomitant fibromyalgia with worse disease activity score in 28 joints, health assessment questionnaire, and short form 36 scores in patients with rheumatoid arthritis.

Aline Ranzolin; João Carlos Tavares Brenol; Markus Bredemeier; Jairo Guarienti; Marcele Rizzatti; Daniel Feldman; Ricardo Machado Xavier

OBJECTIVE To study the association of the presence of fibromyalgia (FM) with the Disease Activity Score in 28 joints (DAS28), the Health Assessment Questionnaire (HAQ), and the Medical Outcomes Study Short Form 36 (SF-36) health survey in patients with rheumatoid arthritis (RA). METHODS A total of 270 outpatients with RA were enrolled in a prospective cross-sectional study. The patients underwent clinical evaluation and application of the HAQ and SF-36 questionnaires. Disease activity was evaluated using the DAS28 score. FM and RA diagnoses were made according to American College of Rheumatology criteria. RESULTS The overall prevalence of FM was 13.4%. This group of patients had a higher prevalence of female sex, older mean age, higher functional class, and longer morning stiffness than patients with only RA. Mean +/- SD DAS28 scores were significantly higher in patients with RA and FM (5.36 +/- 0.99) than in patients with RA only (4.03 +/- 1.39; P < 0.001). In a multivariable linear regression analysis, FM was an important predictor of the DAS28 score, even after adjusting for the erythrocyte sedimentation rate, number of swollen joints, functional class, number of disease-modifying antirheumatic drugs currently in use, current dose of steroids, and articular erosions. HAQ and SF-36 scores were also worse in patients with RA and associated FM. CONCLUSION FM is related to worse scores on the DAS28, HAQ, and SF-36 in patients with RA. The presence of FM may have major implications in the interpretation of the DAS28 score because it is related to higher scores independently of objective evidence of RA activity.


Annals of the Rheumatic Diseases | 2015

Efficacy and safety of tocilizumab in patients with polyarticular-course juvenile idiopathic arthritis: results from a phase 3, randomised, double-blind withdrawal trial

Hermine I. Brunner; Nicolino Ruperto; Zbigniew Zuber; Caroline Keane; Olivier Harari; Andrew Kenwright; Peng Lu; Ruben Cuttica; V. Keltsev; Ricardo Machado Xavier; Inmaculada Calvo; Irina Nikishina; Nadina Rubio-Pérez; E. Alexeeva; Vyacheslav Chasnyk; Gerd Horneff; Violetta Opoka-Winiarska; Pierre Quartier; Clovis A. Silva; Earl D. Silverman; Alberto Spindler; M. Luz Gamir; Alan Martin; Christoph Rietschel; Daniel Siri; Elżbieta Smolewska; Daniel J. Lovell; Alberto Martini; Fabrizio De Benedetti

Objective To evaluate the interleukin-6 receptor inhibitor tocilizumab for the treatment of patients with polyarticular-course juvenile idiopathic arthritis (pcJIA). Methods This three-part, randomised, placebo-controlled, double-blind withdrawal study (NCT00988221) included patients who had active pcJIA for ≥6 months and inadequate responses to methotrexate. During part 1, patients received open-label tocilizumab every 4 weeks (8 or 10 mg/kg for body weight (BW) <30 kg; 8 mg/kg for BW ≥30 kg). At week 16, patients with ≥JIA-American College of Rheumatology (ACR) 30 improvement entered the 24-week, double-blind part 2 after randomisation 1:1 to placebo or tocilizumab (stratified by methotrexate and steroid background therapy) for evaluation of the primary end point: JIA flare, compared with week 16. Patients flaring or completing part 2 received open-label tocilizumab. Results In part 1, 188 patients received tocilizumab (<30 kg: 10 mg/kg (n=35) or 8 mg/kg (n=34); ≥30 kg: n=119). In part 2, 163 patients received tocilizumab (n=82) or placebo (n=81). JIA flare occurred in 48.1% of patients on placebo versus 25.6% continuing tocilizumab (difference in means adjusted for stratification: −0.21; 95% CI −0.35 to −0.08; p=0.0024). At the end of part 2, 64.6% and 45.1% of patients receiving tocilizumab had JIA-ACR70 and JIA-ACR90 responses, respectively. Rates/100 patient-years (PY) of adverse events (AEs) and serious AEs (SAEs) were 480 and 12.5, respectively; infections were the most common SAE (4.9/100 PY). Conclusions Tocilizumab treatment results in significant improvement, maintained over time, of pcJIA signs and symptoms and has a safety profile consistent with that for adults with rheumatoid arthritis. Trial registration number: NCT00988221.


Scandinavian Journal of Rheumatology | 2012

Metabolic syndrome prevalence is increased in rheumatoid arthritis patients and is associated with disease activity

Vr da Cunha; Claiton Viegas Brenol; Jct Brenol; Sandra Cristina Pereira Costa Fuchs; Em Arlindo; Imf Melo; Carlos Alberto Machado; H de Castro Chaves; Ricardo Machado Xavier

Objectives: To evaluate the prevalence of metabolic syndrome (MetS) in patients with rheumatoid arthritis (RA) vs. controls, and to verify possible associations of MetS with specific disease-related factors. Methods: The subjects were 283 RA patients and 226 healthy controls, frequency matched by age and sex. MetS was defined according to National Cholesterol Education Program (NCEP) criteria. Disease activity was evaluated with the Disease Activity Score using 28 joints (DAS28). A standardized clinical evaluation was performed and cardiovascular risk factors were assessed. Results: The criteria for MetS were met by 39.2% RA patients vs. 19.5% in the control group (p < 0.001). Increased waist circumference, elevated blood pressure (BP), and fasting glucose were more frequent in RA patients than controls (p < 0.001 for all associations). By multiple logistic regression analysis (adjusted for age, sex, and years at school), the risk of having MetS was significantly higher for RA patients than for controls [odds ratio (OR) 1.87, 95% confidence interval (CI) 1.17–3.00, p = 0.009]. The DAS28 was significantly higher in RA patients with MetS than in those without MetS (3.59 ± 1.27 vs. 3.14 ± 1.53; p = 0.01). Disease duration, the presence of rheumatoid factor, and extra-articular manifestations were similar for patients with and without MetS. Conclusions: MetS frequency was higher in RA patients than in controls. Among RA patients, MetS was associated with disease activity. The higher prevalence of cardiovascular risk factors in RA suggests that inflammatory processes play a notable role in the development of cardiovascular disease (CVD), and indicates that tight control of systemic inflammatory activity and CVD modifiable risk factors should be recommended.


Annals of the Rheumatic Diseases | 2014

Clinical, radiographic and immunogenic effects after 1 year of tocilizumab-based treatment strategies in rheumatoid arthritis: the ACT-RAY study

Maxime Dougados; Karsten Kissel; Philip G. Conaghan; Emilio Martín Mola; Georg Schett; Roberto Gerli; Michael Sejer Hansen; Howard Amital; Ricardo Machado Xavier; Orrin Troum; Corrado Bernasconi; T. W. J. Huizinga

Objective To assess the 1-year efficacy and safety of a regimen of tocilizumab plus methotrexate or placebo, which was augmented by a treat-to-target strategy from week 24. Methods ACT-RAY was a double-blind, 3-year trial. Adults with active rheumatoid arthritis despite methotrexate were randomised to add tocilizumab to ongoing methotrexate (add-on strategy) or to switch to tocilizumab plus placebo (switch strategy). Tocilizumab 8 mg/kg was administered every 4 weeks. Conventional open-label disease-modifying antirheumatic drugs (DMARDs) other than methotrexate were added at week 24 or later in patients with DAS28>3.2. Results 556 patients were randomised; 85% completed 52 weeks. The proportion of patients receiving open-label DMARDs was comparable in the add-on (29%) and switch (33%) arms. Overall, week 24 results were maintained or further improved at week 52 in both arms. Some endpoints favoured the add-on strategy. Mean changes in Genant-modified Sharp scores were small; more add-on (92.8%) than switch patients (86.1%) had no radiographic progression. At week 52, comparable numbers of patients had antidrug antibodies (ADAs; 1.5% and 2.2% of add-on and switch patients, respectively) and neutralising ADAs (0.7% and 1.8%). Rates of serious adverse events and serious infections per 100 patient-year (PY) were 11.3 and 4.5 in add-on and 16.8 and 5.5 in switch patients. In patients with normal baseline values, alanine aminotransferase elevations >3× upper limit of normal were observed in 11% of add-on and 3% of switch patients. Conclusions Despite a trend favouring the add-on strategy, these data suggest that both tocilizumab add-on and switch strategies led to meaningful clinical and radiographic responses.


Lupus | 2009

Association of the HLA-G 14 bp polymorphism with systemic lupus erythematosus:

Tiago Degani Veit; Eaa Cordero; T Mucenic; Odirlei André Monticielo; Jct Brenol; Ricardo Machado Xavier; A Delgado-Cañedo; Jab Chies

Human leukocyte antigen-G (HLA-G) is a nonclassical class I major histocompatibility complex molecule which is induced at the course of inflammatory pathologies, and its expression has been suggested as a possible mechanism of tissue protection against autoimmune inflammatory responses, therefore acting as a mechanism of immune surveillance. We investigated the influence of the 14 bp polymorphism of the HLA-G gene on systemic lupus erythematosus (SLE) by analyzing 293 patients with SLE and 460 healthy controls. The patient’s group was not in Hardy–Weinberg equilibrium, presenting an excess of heterozygotes (P = 0.014). The heterozygote group exhibited lower systemic lupus erythematosus disease activity indexes than the homozygous deletion group and the homozygous insertion group (mean value = 2.29 against 2.97 and 3.4, respectively, P = 0.035). Photosensitive patients showed a higher frequency of heterozygotes and an equivalent lower frequency of homozygotes for deletion; on the other hand, patients without arthritis presented a higher frequency of heterozygotes than the arthritis group and also a lower frequency of the del/del genotype. Overall, our results support the idea of a role of the HLA-G insertion/deletion polymorphism and therefore a role for the HLA-G molecule, on the pathology of SLE.


Clinical Rheumatology | 2008

The role of mannose-binding lectin in systemic lupus erythematosus

Odirlei André Monticielo; Tamara Mucenic; Ricardo Machado Xavier; João Carlos Tavares Brenol; José Artur Bogo Chies

Susceptibility to systemic lupus erythematosus (SLE) is associated with genetic, hormonal, immunological, and environmental factors. Many genes have been related with the appearance of SLE, including several loci that code different complement components and their receptors. Some genetic deficiencies of complement molecules are strongly associated with SLE, probably because these deficiencies could cause decreased clearance of apoptotic cell material. As a consequence of the apoptotic material accumulation, high levels of autoantigens can be presented inappropriately to the immune system in an inflammatory context, resulting in an imbalance on the mechanisms of immunological tolerance, immune system activation, and autoantibody production. Recent studies proposed a role to the mannose-binding lectin (MBL) in the SLE physiopathogenesis. This protein activates the complement system, and the presence of several polymorphisms at the promoter and coding regions of the MBL-2 gene determines alterations at the plasma levels of MBL. Some of these polymorphisms have been associated with SLE susceptibility, as well as with clinical and laboratory typical features of this disease, cardiovascular events, and infections. Besides, it has been described that the presence of anti-MBL autoantibodies in sera of SLE patients can influence MBL plasma levels and its functional activity.


Annals of the Rheumatic Diseases | 2014

Clinical and radiographic outcomes at 2 years and the effect of tocilizumab discontinuation following sustained remission in the second and third year of the ACT-RAY study

T. W. J. Huizinga; Philip G. Conaghan; Emilio Martín-Mola; Georg Schett; Howard Amital; Ricardo Machado Xavier; Orrin Troum; Maher Aassi; Corrado Bernasconi; Maxime Dougados

Objective To assess the efficacy and safety of tocilizumab (TCZ) plus methotrexate/placebo (MTX/PBO) over 2 years and the course of disease activity in patients who discontinued TCZ due to sustained remission. Methods ACT-RAY was a double-blind 3-year trial. Patients with active rheumatoid arthritis despite MTX were randomised to add TCZ to ongoing MTX (add-on strategy) or switch to TCZ plus PBO (switch strategy). Using a treat-to-target approach, open-label conventional synthetic disease-modifying antirheumatic drugs (csDMARDs), other than MTX, were added from week 24 if Disease Activity Score in 28 joints based on erythrocyte sedimentation rate (DAS28-ESR) >3.2. Between weeks 52 and 104, patients in sustained clinical remission (DAS28-ESR <2.6 at two consecutive visits 12 weeks apart) discontinued TCZ and were assessed every 4 weeks for 1 year. If sustained remission was maintained, added csDMARDs, then MTX/PBO, were discontinued. Results Of the 556 randomised patients, 76% completed year 2. Of patients entering year 2, 50.4% discontinued TCZ after achieving sustained remission and 5.9% achieved drug-free remission. Most patients who discontinued TCZ (84.0%) had a subsequent flare, but responded well to TCZ reintroduction. Despite many patients temporarily stopping TCZ, radiographic progression was minimal, with differences favouring add-on treatment. Rates of serious adverse events and serious infections per 100 patient-years were 12.2 and 4.4 in add-on and 15.0 and 3.7 in switch patients. In patients with normal baseline values, alanine aminotransferase elevations >3×upper limit of normal were more frequent in add-on (14.3%) versus switch patients (5.4%). Conclusions Treat-to-target strategies could be successfully implemented with TCZ to achieve sustained remission, after which TCZ was stopped. Biologic-free remission was maintained for about 3 months, but most patients eventually flared. TCZ restart led to rapid improvement. Trial registration number NCT00810199.


Tissue Antigens | 2008

Association of the HLA-G 14-bp insertion/deletion polymorphism with juvenile idiopathic arthritis and rheumatoid arthritis

Tiago Degani Veit; Priscilla Vianna; Iloite Maria Scheibel; Claiton Viegas Brenol; João Carlos Tavares Brenol; Ricardo Machado Xavier; Andrés Delgado-Cañedo; Jorge Eduardo Gutierrez; Ana Paula Carneiro Brandalize; Lavinia Schuler-Faccini; José Artur Bogo Chies

We tested the possible association of the 14-bp polymorphism of the HLA-G gene in the course of two inflammatory diseases, rheumatoid arthritis (RA) and juvenile idiopathic arthritis (JIA). Patients and controls were genotyped for the 14-bp polymorphism by polymerase chain reaction with specific primers for the exon 8 of the human leukocyte antigen (HLA)-G gene and the amplified fragment was visualized in a 6% polyacrylamide gel. A total of 106 JIA patients, 265 RA patients, 356 healthy adults and 85 healthy children were genotyped for the 14-bp polymorphism. Female JIA patients presented a higher frequency of the -14 bp allele when compared with female healthy children (0.743 and 0.500, corrected P=0.003), which reflected in the JIA group as a whole. This increased frequency of the -14-bp allele was observed in all JIA subtypes. In RA patients, no differences in allelic and genotypic frequencies were observed between patients and controls. No correlations were observed among genotype and disease severity or clinical manifestations. Our data suggest that the HLA-G -14 bp allele is probably a risk factor for JIA, mainly in females. Considering the differences observed in relation to gender, we suggest that hormonal differences can interfere with the development of JIA. Considering the RA patients, our data agree with results from the literature and highlight the differences in the etiology of RA and JIA.

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Dive into the Ricardo Machado Xavier's collaboration.

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João Carlos Tavares Brenol

Universidade Federal do Rio Grande do Sul

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Claiton Viegas Brenol

Universidade Federal do Rio Grande do Sul

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Odirlei André Monticielo

Universidade Federal do Rio Grande do Sul

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Lidiane Isabel Filippin

Universidade Federal do Rio Grande do Sul

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Charles Lubianca Kohem

Universidade Federal do Rio Grande do Sul

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Vivian de Oliveira Nunes Teixeira

Universidade Federal do Rio Grande do Sul

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José Artur Bogo Chies

Universidade Federal do Rio Grande do Sul

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Patricia Gnieslaw de Oliveira

Universidade Federal do Rio Grande do Sul

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Tamara Mucenic

Universidade Federal do Rio Grande do Sul

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Priscila Schmidt Lora

Universidade Federal do Rio Grande do Sul

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