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1.
BMC Med ; 18(1): 362, 2020 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-33239013

RESUMO

BACKGROUND: Patients with coeliac disease (CD) commonly report a variety of adverse symptoms to gluten, but descriptions of the symptomatic response in the literature may have been confounded by the presence of food components such as fermentable carbohydrates (FODMAPs) causing symptoms of irritable bowel syndrome independent of gluten. In recent unmasked and masked low FODMAP gluten challenge studies in small groups of treated CD patients, nausea and vomiting were shown to be the key symptoms associated with serum interleukin (IL)-2 release. Our objective was to utilise a large and diverse cohort of people with CD undertaking a standardised gluten food challenge to characterise the demographic, genetic and clinical factors influencing the severity and timing of acute gluten reactions and IL-2 production. METHODS: A total of 295 adults treated for CD were observed for 6 h after an unmasked food challenge consisting of 10 g vital wheat gluten (low in FODMAPs) in 100 ml water. Assessments included patient-reported outcomes, serum IL-2 and adverse events. Responses were analysed according to patient characteristics, HLA-DQ genotype, duodenal histology and response to a second gluten challenge. RESULTS: Peak symptom severity was at 3 h (median severity 5/10). Peak IL-2 was at 4 h (median 4 pg/ml, range undetectable to 1028 pg/ml). Older age, older age at diagnosis, HLA-DQ2.5 positivity and homozygosity for HLA-DQB1*02 were each significantly associated with IL-2 elevations after gluten. Patients positive for HLA-DQ2.5, DQ8, DQ2.2 or DQ7 showed elevated IL-2 after gluten. Patient factors were not significantly associated with severity of digestive symptoms, but symptoms were correlated to one another and serum IL-2. Gluten challenge after 5 months caused more vomiting and higher IL-2 levels, but responses correlated with the first. CONCLUSIONS: Gluten-induced symptoms and cytokine release is common in adults with treated CD. Age, genetics and previous response to gluten predict these acute reactions to gluten challenge. Structured symptom assessment and serum IL-2 after standardised gluten challenge may inform on patient diagnosis, the role of gluten in symptomatology and the need for adjunctive treatment. TRIAL REGISTRATION: ClinicalTrials.gov , NCT03644069 Registered 21 May 2018.


Assuntos
Doença Celíaca/diagnóstico , Citocinas/metabolismo , Glutens/efeitos adversos , Adulto , Doença Celíaca/dietoterapia , Feminino , Humanos , Masculino , Medidas de Resultados Relatados pelo Paciente
2.
Circulation ; 138(18): 1963-1973, 2018 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-29967197

RESUMO

BACKGROUND: We previously reported exogenous antifactor Xa (FXa) activity as a pharmacokinetic surrogate marker for edoxaban plasma concentrations. Inhibition of endogenous FXa activity is a more biologically relevant pharmacodynamic measure of edoxaban activity. Here we describe the value of endogenous FXa activity as a pharmacodynamic marker linking edoxaban concentrations and clinical outcomes in the ENGAGE AF-TIMI 48 trial (Effective Anticoagulation With Factor Xa Next Generation in Atrial Fibrillation-Thrombolysis in Myocardial Infarction Study 48). METHODS: In ENGAGE AF-TIMI 48, edoxaban was administered in higher dose (60/30 mg QD) and lower dose (30/15 mg QD) regimens. Both regimens incorporated a 50% dose reduction in patients with characteristics known to increase edoxaban concentration. Pharmacokinetic-pharmacodynamic modeling was performed in a subgroup of 3029 patients who had samples collected for endogenous FXa activity (measured using an assay after endogenous FX was activated with Russell viper venom). RESULTS: Endogenous FXa activity decreased with increasing edoxaban concentrations of ≤440 ng/mL, indicating that inhibition of endogenous FXa activity is saturated above this concentration threshold. Baseline endogenous FXa activity averaged 92.1±20.9% (relative to normal control samples) and was lower with older age, with lower body weight, and in male patients. Model-predicted 24-hour average percentages of inhibition of endogenous FXa activity were 35.8±5.18, 29.1±3.92, 21.9±3.80, and 16.4±2.70 for the higher dose edoxaban regimen 60 mg, dose-reduced higher dose edoxaban regimen 30 mg, lower dose edoxaban regimen 30 mg, and dose-reduced lower dose edoxaban regimen 15 mg groups, respectively. A greater average percentage of inhibition of endogenous FXa activity was associated with a lower incidence of ischemic stroke or systemic embolism and a higher risk of major bleeding ( P<0.001). In a typical subject, the predicted risks for the 10th and 90th percentiles of inhibition of endogenous FXa activity were 1.04% and 0.57% for incidence of ischemic stroke or systemic embolism and 1.35% and 2.33% for major bleeding, respectively. CONCLUSIONS: The extent of inhibition of endogenous FXa activity is influenced by edoxaban dosing and clinical characteristics, and it is associated with both antithrombotic benefit and risk of bleeding. This approach of linking endogenous FXa activity to clinical outcomes may be used to guide dose selection in future clinical trials, monitor patients in certain clinical scenarios, or refine the doses of oral FXa inhibitors in patients who require precise anticoagulation therapy. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT00781391.


Assuntos
Inibidores do Fator Xa/metabolismo , Fator Xa/metabolismo , Piridinas/metabolismo , Tiazóis/metabolismo , Idoso , Relação Dose-Resposta a Droga , Embolia/etiologia , Inibidores do Fator Xa/efeitos adversos , Inibidores do Fator Xa/sangue , Inibidores do Fator Xa/uso terapêutico , Feminino , Meia-Vida , Hemorragia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/tratamento farmacológico , Piridinas/efeitos adversos , Piridinas/sangue , Piridinas/uso terapêutico , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Tiazóis/efeitos adversos , Tiazóis/sangue , Tiazóis/uso terapêutico , Resultado do Tratamento
3.
Br J Clin Pharmacol ; 82(6): 1591-1600, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27530188

RESUMO

AIMS: Edoxaban, a novel factor Xa inhibitor, is a substrate of cytochrome P450 3 A4 (CYP3A4) and the efflux transporter P-glycoprotein (P-gp). Three edoxaban drug-drug interaction studies examined the effects of P-gp inhibitors with varying degrees of CYP3A4 inhibition. METHODS: In each study, healthy subjects received a single oral dose of 60 mg edoxaban with or without an oral dual P-gp/CYP3A4 inhibitor as follows: ketoconazole 400 mg once daily for 7 days, edoxaban on day 4; erythromycin 500 mg four times daily for 8 days, edoxaban on day 7; or single dose of cyclosporine 500 mg with edoxaban. Serial plasma samples were obtained for pharmacokinetics and pharmacodynamics. Safety was assessed throughout the study. RESULTS: Coadministration of ketoconazole, erythromycin, or cyclosporine increased edoxaban total exposure by 87%, 85%, and 73%, respectively, and the peak concentration by 89%, 68%, and 74%, respectively, compared with edoxaban alone. The half-life did not change appreciably. Exposure of M4, the major active edoxaban metabolite, was consistent when edoxaban was administered alone or with ketoconazole and erythromycin. With cyclosporine, M4 total exposure increased by 6.9-fold and peak exposure by 8.7-fold, suggesting an additional interaction. Pharmacodynamic effects were reflective of increased edoxaban exposure. No clinically significant adverse events were observed. CONCLUSIONS: Administration of dual inhibitors of P-gp and CYP3A4 increased edoxaban exposure by less than two-fold. This effect appears to be primarily due to inhibition of P-gp. The impact of CYP3A4 inhibition appears to be less pronounced, and its contribution to total clearance appears limited in healthy subjects.


Assuntos
Ciclosporina/farmacocinética , Eritromicina/farmacocinética , Inibidores do Fator Xa/farmacocinética , Cetoconazol/farmacocinética , Piridinas/farmacocinética , Tiazóis/farmacocinética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Administração Oral , Adolescente , Adulto , Estudos Cross-Over , Ciclosporina/administração & dosagem , Ciclosporina/sangue , Citocromo P-450 CYP3A/metabolismo , Esquema de Medicação , Interações Medicamentosas , Eritromicina/administração & dosagem , Eritromicina/sangue , Inibidores do Fator Xa/administração & dosagem , Inibidores do Fator Xa/sangue , Voluntários Saudáveis , Humanos , Cetoconazol/administração & dosagem , Cetoconazol/sangue , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Piridinas/administração & dosagem , Piridinas/sangue , Especificidade por Substrato , Tiazóis/administração & dosagem , Tiazóis/sangue , Adulto Jovem
4.
Lancet Gastroenterol Hepatol ; 8(5): 446-457, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36898393

RESUMO

BACKGROUND: A gluten-free diet is insufficient to treat coeliac disease because intestinal injury persists and acute reactions with cytokine release follow gluten exposure. Nexvax2 is a specific immunotherapy using immunodominant peptides recognised by gluten-specific CD4+ T cells that might modify gluten-induced disease in coeliac disease. We aimed to assess the effects of Nexvax2 on gluten-induced symptoms and immune activation in patients with coeliac disease. METHODS: This was a randomised, double-blind, placebo-controlled phase 2 trial done at 41 sites (29 community, one secondary, and 11 tertiary centres) in the USA, Australia, and New Zealand. Patients with coeliac disease aged 18-70 years who had excluded gluten for at least 1 year, were HLA-DQ2.5 positive, and had a worsening of symptoms after an unmasked 10 g vital gluten challenge were eligible for inclusion. Patients were stratified by HLA-DQ2.5 status (HLA-DQ2.5 non-homozygous vs homozygous). Patients who were non-homozygous were centrally (ICON; Dublin, Ireland) randomly assigned (1:1) to receive subcutaneous Nexvax2 (non-homozygous Nexvax2 group) or saline (0·9% sodium chloride; non-homozygous placebo group) twice a week escalating from 1 µg to 750 µg during the first 5 weeks followed by 11 weeks of maintenance therapy at 900 µg per dose. The exploratory homozygous group was centrally randomly assigned (2:1) to receive Nexvax2 (homozygous Nexvax2 group) or placebo (homozygous placebo group); patients who were homozygous received the same dosage as those who were non-homozygous. The primary endpoint was change in coeliac disease patient reported outcomes (total gastrointestinal domain) from pretreatment baseline to the day of masked bolus 10 g vital gluten challenge given in week 14 analysed in the non-homozygous intention-to-treat population. The trial is registered with ClinicalTrials.gov, NCT03644069. FINDINGS: Between Sept 21, 2018, and April 24, 2019, 383 volunteers were screened for inclusion, of whom 179 (47%; 133 [74%] women, 46 [26%] men; median age 41 years [IQR 33-55]) were randomly assigned. One (1%) of 179 patients was excluded from analysis due to misassignment of genotype. The non-homozygous Nexvax2 group included 76 patients, the non-homozygous placebo group included 78 patients, the homozygous Nexvax2 group included 16 patients, and the homozygous placebo group included eight patients. The study was discontinued after planned interim analysis of 66 patients who were non-homozygous. We report an unmasked post-hoc analysis of all available data for the primary endpoint and secondary symptom-based endpoints combining data from 67 (66 were assessed in the planned interim analysis for the primary endpoint). Mean change from baseline to day of first masked gluten challenge in total gastrointestinal score for the non-homozygous Nexvax2 group was 2·86 (SD 2·28) compared with 2·63 (2·07) for the non-homozygous placebo group (p=0·43). Adverse events were similar between all patients who received Nexvax2 and those who received placebo. Serious adverse events were reported in five (3%) of 178 patients (two [2%] of 92 who received Nexvax2 and three [4%] of 82 who received placebo). One patient in the non-homozygous Nexvax2 group had a serious adverse event that occurred during gluten challenge (left-sided mid-back muscle strain with imaging suggestive of partial left kidney infarction). Serious adverse events were reported for three (4%) of 78 patients in the non-homozygous placebo group (one each with exacerbation of asthma and appendicitis, and one who had forehead abscess, conjunctivitis, and folliculitis) and one (1%) patient in the non-homozygous Nexvax2 group developed a pulmonary embolism. The most frequent adverse events in all 92 patients who received Nexvax2 compared with all 86 patients who received placebo were nausea (44 [48%] of 92 patients who received Nexvax2 vs 29 (34%) of 86 patients who received placebo), diarrhoea (32 [35%] vs 25 [29%]), abdominal pain (31 [34%] vs 27 [31%]), headache 32 [35%] vs 20 [23%]), and fatigue (24 [26%] vs 31 [36%]). INTERPRETATION: Nexvax2 did not reduce acute gluten-induced symptoms. Masked bolus vital gluten challenge provides an alternative to extended gluten challenge in efficacy studies for coeliac disease. FUNDING: ImmusanT.


Assuntos
Doença Celíaca , Masculino , Adulto , Humanos , Feminino , Doença Celíaca/tratamento farmacológico , Glutens/efeitos adversos , Peptídeos/uso terapêutico , Imunoterapia
5.
Front Immunol ; 12: 661622, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093551

RESUMO

Improved blood tests assessing the functional status of rare gluten-specific CD4+ T cells are needed to effectively monitor experimental therapies for coeliac disease (CD). Our aim was to develop a simple, but highly sensitive cytokine release assay (CRA) for gluten-specific CD4+ T cells that did not require patients to undergo a prior gluten challenge, and would be practical in large, multi-centre clinical trials. We developed an enhanced CRA and used it in a phase 2 clinical trial ("RESET CeD") of Nexvax2, a peptide-based immunotherapy for CD. Two participants with treated CD were assessed in a pilot study prior to and six days after a 3-day gluten challenge. Dye-dilution proliferation in peripheral blood mononuclear cells (PBMC) was assessed, and IL-2, IFN-γ and IL-10 were measured by multiplex electrochemiluminescence immunoassay (ECL) after 24-hour gluten-peptide stimulation of whole blood or matched PBMC. Subsequently, gluten-specific CD4+ T cells in blood were assessed in a subgroup of the RESET CeD Study participants who received Nexvax2 (maintenance dose 900 µg, n = 12) or placebo (n = 9). The pilot study showed that gluten peptides induced IL-2, IFN-γ and IL-10 release from PBMCs attributable to CD4+ T cells, but the PBMC CRA was substantially less sensitive than whole blood CRA. Only modest gluten peptide-stimulated IL-2 release could be detected without prior gluten challenge using PBMC. In contrast, whole blood CRA enabled detection of IL-2 and IFN-γ before and after gluten challenge. IL-2 and IFN-γ release in whole blood required more than 6 hours incubation. Delay in whole blood incubation of more than three hours from collection substantially reduced antigen-stimulated IL-2 and IFN-γ secretion. Nexvax2, but not placebo treatment in the RESET CeD Study was associated with significant reductions in gluten peptide-stimulated whole blood IL-2 and IFN-γ release, and CD4+ T cell proliferation. We conclude that using fresh whole blood instead of PBMC substantially enhances cytokine secretion stimulated by gluten peptides, and enables assessment of rare gluten-specific CD4+ T cells without requiring CD patients to undertake a gluten challenge. Whole blood assessment coupled with ultra-sensitive cytokine detection shows promise in the monitoring of rare antigen-specific T cells in clinical studies.


Assuntos
Antígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Doença Celíaca/imunologia , Citocinas/imunologia , Glutens/imunologia , Fragmentos de Peptídeos/imunologia , Adulto , Idoso , Sequência de Aminoácidos , Linfócitos T CD4-Positivos/metabolismo , Doença Celíaca/sangue , Doença Celíaca/diagnóstico , Células Cultivadas , Citocinas/sangue , Método Duplo-Cego , Feminino , Humanos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Peptídeos/imunologia , Peptídeos/metabolismo , Sensibilidade e Especificidade
6.
Aliment Pharmacol Ther ; 51(2): 244-252, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31769533

RESUMO

BACKGROUND: In patients with coeliac disease, FODMAPs in gluten-containing foods, and participant anticipation of a harmful ('nocebo') effect, may contribute to acute symptoms after gluten challenge. AIM: To establish acute gluten-specific symptoms linked to immune activation in coeliac disease METHODS: We included 36 coeliac disease patients on a gluten-free diet receiving placebo in the RESET CeD trial. Double-blind, bolus vital wheat gluten (~6-g gluten protein) and sham challenges low in FODMAPs were consumed 2 weeks apart. Assessments included daily Coeliac Disease Patient Reported Outcome (CeD PRO) symptom scores (0-10), adverse events and serum interleukin-2 (baseline and 4 hours). RESULTS: Median CeD PRO score for nausea increased most (sham: 0 vs gluten: 5.5; P < .001). Apart from tiredness (1 vs 4, P = .005) and headache (0 vs 2, P = .002), changes in other symptoms were small or absent. Only nausea increased significantly in occurrence with gluten (11% vs 69%, P < .001). Without nausea, only tiredness and flatulence were common after gluten. Nausea (6% vs 61%, P < .001; median onset: 1:34 hours) and vomiting (0% vs 44%, P < .001; 1:51 hours) were the only adverse events more common with gluten than sham. Interleukin-2 was always below the level of quantitation (0.5 pg/mL) at baseline, and after sham. Interleukin-2 was elevated after gluten in 97% of patients (median fold-change: 20), and correlated with severity of nausea (rs  = .49, P = .0025) and occurrence of vomiting (P = .0005). CONCLUSIONS: Nausea and vomiting are relatively specific indicators of acute gluten ingestion, and correlate with immune activation. IBS-like symptoms without nausea are unlikely to indicate recent gluten exposure.


Assuntos
Doença Celíaca/complicações , Doença Celíaca/imunologia , Carboidratos da Dieta/efeitos adversos , Glutens/efeitos adversos , Doenças do Sistema Imunitário/etiologia , Náusea/etiologia , Vômito/etiologia , Doença Aguda , Adulto , Doença Celíaca/metabolismo , Doença Celíaca/terapia , Dieta/efeitos adversos , Dieta Livre de Glúten , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/farmacologia , Progressão da Doença , Método Duplo-Cego , Feminino , Fermentação/efeitos dos fármacos , Glutens/administração & dosagem , Glutens/farmacologia , Humanos , Sistema Imunitário/efeitos dos fármacos , Sistema Imunitário/fisiologia , Absorção Intestinal/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Efeito Nocebo , Placebos
7.
J Clin Pharmacol ; 49(1): 50-62, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18948412

RESUMO

Pharmacokinetic (PK) and exposure-response modeling of a selective sphingosine 1-phosphate receptor-1 modulator (CS-0777) was conducted in an iterative process to guide early clinical development decisions. A model based on preclinical data from monkeys was extrapolated to humans to support a single ascending dose (SAD) study. The model was updated after each cohort, providing guidance on both maximal inhibition and time to recovery for lymphocyte counts. A 2-compartment PK model with first-order absorption and elimination was found to describe the monkey and human datasets. The relationship between lymphocyte counts and active metabolite (M-1) concentrations was modeled via an indirect response model, whereby M-1 inhibited the reentry of lymphocytes to the circulation. The indirect-response model based on SAD data had an Imax of approximately 85% and an IC50 of 0.24 ng/mL. Additionally, based on SAD data, similar models were developed for lymphocyte subsets, including CD4 cells. Subsequently, simulations were utilized to design a multiple ascending dose study with adaptive dosing regimens that would meet targeted pharmacodynamic (PD) response thresholds (eg, minimum 40% reduction in lymphocytes) while maintaining CD4 counts above a reasonable safety threshold. In conclusion, model-based development and use of adaptive designs for dose optimization can reduce the time and number of subjects needed in early clinical development.


Assuntos
Amino Álcoois/farmacocinética , Linfócitos/efeitos dos fármacos , Lisofosfolipídeos/farmacologia , Modelos Biológicos , Pró-Fármacos/farmacologia , Pirróis/farmacocinética , Receptores de Lisoesfingolipídeo/fisiologia , Esfingosina/análogos & derivados , Administração Oral , Adolescente , Adulto , Amino Álcoois/administração & dosagem , Amino Álcoois/farmacologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Estudos de Coortes , Relação Dose-Resposta a Droga , Método Duplo-Cego , Humanos , Contagem de Linfócitos , Subpopulações de Linfócitos/citologia , Subpopulações de Linfócitos/efeitos dos fármacos , Linfócitos/citologia , Lisofosfolipídeos/administração & dosagem , Lisofosfolipídeos/farmacocinética , Masculino , Pessoa de Meia-Idade , Pró-Fármacos/administração & dosagem , Pró-Fármacos/farmacocinética , Pirróis/administração & dosagem , Pirróis/farmacologia , Esfingosina/administração & dosagem , Esfingosina/farmacocinética , Esfingosina/farmacologia , Adulto Jovem
8.
Aliment Pharmacol Ther ; 50(5): 547-555, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31407810

RESUMO

BACKGROUND: Nexvax2 contains three gluten-derived peptides, intended to tolerize coeliac disease patients to gluten. Sequences cover six epitopes that trigger immune activation in human leucocyte antigen-DQ2.5-positive patients, most notably after an initial dose. Patients experience gastrointestinal symptoms with increases in serum interleukin-2. Consistent with Nexvax2's induction of non-responsiveness, reactivity disappears after repeated doses, or is avoided with gradual dose escalation. Early clinical trials used intradermal dosing, but pharmacokinetics and rapid onset of effect suggest that subcutaneous delivery may also be effective. AIMS: To document the relative bioavailability of Nevax2 peptides after subcutaneous and intradermal dosing, and the tolerability and ability of subcutaneous dosing to induce non-responsiveness to Nexvax2 peptides. METHODS: A randomised, double-blind, placebo-controlled study was conducted to assess plasma pharmacokinetics after subcutaneous and intradermal Nexvax2 dosing in HLA DQ2.5-positive patients, who had symptoms after an oral gluten challenge. Randomisation was to semi-weekly Nexvax2 (n = 12) or placebo (n = 2) injections, over a 5-week subcutaneous dose escalation and 2-week maintenance period, the latter with four doses of 900 µg, two subcutaneous and two intradermal. Post-dose circulating peptide and interleukin-2 levels were assessed. Investigators recorded adverse events experienced by patients. RESULTS: Subcutaneous dosing resulted in slightly greater exposure. Interleukin-2 responses were seen with the gluten challenge but not after subcutaneous or intradermal dosing of 900 µg. Adverse events were generally mild and self-limited. CONCLUSIONS: Subcutaneous and intradermal dosing of Nexvax2 yield similar bioavailability of constituent peptides; subcutaneous dose escalation avoids an immune response to dominant gluten epitopes.


Assuntos
Doença Celíaca/tratamento farmacológico , Drogas em Investigação/administração & dosagem , Drogas em Investigação/farmacocinética , Glutens/administração & dosagem , Glutens/farmacocinética , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/farmacocinética , Adolescente , Adulto , Disponibilidade Biológica , Doença Celíaca/metabolismo , Criança , Relação Dose-Resposta a Droga , Método Duplo-Cego , Drogas em Investigação/efeitos adversos , Feminino , Glutens/efeitos adversos , Humanos , Imunomodulação , Injeções Intradérmicas , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/efeitos adversos , Placebos , Adulto Jovem
9.
Aliment Pharmacol Ther ; 50(8): 901-910, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31483515

RESUMO

BACKGROUND: Coeliac disease patients on a gluten-free diet experience reactions to gluten, but these are not well characterised or understood. Systemic cytokine release was recently linked to reactivation of gluten immunity in coeliac disease. AIM: To define the nature and time-course of symptoms and interleukin-2 changes specific for coeliac disease patients. METHODS: 25 coeliac disease patients on a gluten-free diet and 25 healthy volunteers consumed a standardised 6 gram gluten challenge. Coeliac Disease Patient-Reported Outcome survey and global digestive symptom assessment were completed hourly up to 6 hours after gluten. Adverse events over 48 hours were recorded. Serum interleukin-2 was measured at baseline, and 2, 4 and 6 hours. RESULTS: Serum interleukin-2 was always undetectable in healthy controls, whereas it was undetectable at baseline and elevated >0.5 pg/ml at 4 hours in 92% of coeliac disease patients. All patient-reported outcome severity scores increased significantly after gluten in coeliac disease patients (P < .001 Wilcoxon signed rank test), but not in controls. Symptoms began after 1 hour, and peaked in the third. Nausea and vomiting characterised severe reactions, but mild reactions were limited to headache and tiredness. Peak interleukin-2 correlated with symptom severity, particularly for nausea and vomiting. CONCLUSIONS: Serum interleukin-2 elevations correlate with timing and severity of symptoms after gluten in coeliac disease. Standardised bolus gluten food challenge and interleukin-2 assessment could provide a valuable clinical test to monitor and diagnose coeliac disease in patients established on a gluten-free diet.


Assuntos
Doença Celíaca/sangue , Doença Celíaca/diagnóstico , Dieta Livre de Glúten , Glutens/efeitos adversos , Interleucina-2/sangue , Adulto , Biomarcadores/sangue , Citocinas/sangue , Fadiga/sangue , Fadiga/induzido quimicamente , Fadiga/diagnóstico , Feminino , Glutens/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
10.
J Clin Pharmacol ; 48(12): 1420-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18936283

RESUMO

A model-based approach was implemented for the development of the proliferator-activated receptor gamma (PPARgamma) agonist rivoglitazone. Population pharmacokinetic and pharmacodynamic models were developed using data collected from 2 phase I and 2 phase II studies in healthy volunteers and participants with type 2 diabetes mellitus. A 2-compartment model with first-order absorption and elimination and an absorption time lag best described rivoglitazone pharmacokinetics. Modified indirect-response models were used to characterize changes in fasting plasma glucose, HbA(1c), and hemodilution as a function of rivoglitazone plasma concentrations. In addition, differences in hemodilution among participants correlated with the incidence of edema. Current use of oral antidiabetic medication was a significant covariate for the fasting plasma glucose-HbA(1c) exposure-response model. Using a learn-and-confirm process, models developed prior to the second phase II study were able to make valid predictions for exposures and response variables in that study. In future studies, seamless designs can be supported by models such as those developed here.


Assuntos
Modelos Biológicos , PPAR gama/agonistas , Tiazolidinedionas/farmacocinética , Adiponectina/sangue , Administração Oral , Algoritmos , Glicemia/análise , Cromatografia Líquida , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Relação Dose-Resposta a Droga , Feminino , Hemoglobinas Glicadas/análise , Humanos , Masculino , Taxa de Depuração Metabólica , Projetos de Pesquisa , Espectrometria de Massas em Tandem , Tiazolidinedionas/sangue , Tiazolidinedionas/uso terapêutico
11.
Br J Clin Pharmacol ; 66(1): 60-70, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18522627

RESUMO

AIM: To develop a pain relief model for a cyclooxygenase (COX)-2 inhibitor, CS-706, that permits prediction of doses for acute pain relief in Japanese and Western populations. METHODS: A categorical response model was developed to describe the probability of pain relief (PR) over time for a Phase 2a study. Models were also developed to describe patient's use of rescue medication and onset of pain relief. RESULTS: The placebo response was described by a first-order increase in PR that achieved a stable response after 4 h. The effect of CS-706 on PR was described using an E(max) model; the plasma concentration of CS-706 producing 50% of the maximum response was estimated to be 87 ng ml(-1), the median peak plasma concentration achieved after a 50-mg oral dose. The probability of rescue medication (REMD) decreased over time and was a function of the last observed PR score. This probability was < 16% for patients with a PR score > or =2. The probability of experiencing meaningful PR was 98% in patients who did not require REMD and 47% in those who required REMD. For patients who did not require REMD, the median onset time of meaningful pain relief (TMPR) decreased with increasing doses. In patients who required REMD, there was a saturable decline in TMPR, with the greatest improvement occurring from placebo to 50-mg doses. CONCLUSIONS: The set of models developed permitted compilation of multiple dose-response curves for dose selection of CS-706 in Westerners and facilitated scaling of doses to a Japanese population.


Assuntos
Analgesia/métodos , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Medição da Dor/psicologia , Dor Pós-Operatória/tratamento farmacológico , Pirróis/uso terapêutico , Sulfonamidas/uso terapêutico , Relação Dose-Resposta a Droga , Método Duplo-Cego , Seguimentos , Humanos , Modelos Teóricos , Extração Dentária/efeitos adversos , Resultado do Tratamento
12.
Clin Ther ; 29(3): 399-412, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17577461

RESUMO

BACKGROUND: CS-706 is a cyclooxygenase-2 (COX-2)-selective inhibitor with an in vitro selectivity ratio (COX-1:COX-2) similar to that of celecoxib. It has exhibited analgesic, anti-inflammatory, and antitumor properties in animal models. OBJECTIVES: This study evaluated the tolerability of single doses of CS-706 and compared the analgesic efficacy of CS-706 with that of celecoxib and placebo in the dental pain model. METHODS: This was a randomized, double-blind, double-dummy, active- and placebo-controlled study. Healthy male and female subjects with moderate to severe pain intensity (PI) after dental surgery were randomized ( approximately 50 per group) to receive a single oral dose of CS-706 10, 50, 100, or 200 mg; celecoxib 400 mg; or placebo. PI and pain relief (PR) were measured on categorical and visual analog scales through 24 hours after the dose. The primary efficacy variable was the time-weighted sum of PR scores at 4 hours after the dose (TOPAR4). The onset of analgesia was assessed by calculating the pain intensity difference (PID). Perceptible and meaningful pain relief were assessed using a 2-stopwatch method. RESULTS: The majority of subjects were female (62.0%) and white (59.5%). Subjects' mean (SD) age was 22.6 (3.9) years, and their mean body mass index was 25.3 (5.1) kg/m(2). All doses of CS-706 were associated with significant analgesic efficacy compared with placebo based on the primary end point, TOPAR4 (P<0.001), and on all secondary end points (P<0.05, comparisons of all CS-706 doses vs placebo) with the exception of time to 100% PR for CS-706 10 mg. Single 50-, 100-, and 200-mg doses of CS-706 also were significantly more effective than celecoxib for TOPAR4 (P=0.036, P=0.004, and P=0.006, respectively). The onset of analgesia (PID >or= 1) for all CS-706 doses occurred within 1 hour after dosing (P<0.001 vs placebo). The median duration of analgesia, measured as the time to administration of rescue medication, was significantly greater for all doses of CS-706 compared with placebo (5.7 hours for CS-706 10 mg, >24 hours for CS-706 50, 100, and 200 mg, and 1.7 hours for placebo; P<0.001 for CS-706 50, 100, and 200 mg). These data suggest that once-daily administration of CS-706 may be effective in providing relief of acute pain. The incidence of adverse events was similar among all treatment groups. Adverse events occurring in >or= 5 % of subjects in any treatment group were nausea, vomiting, dry socket, dizziness, headache, and paresthesia. CONCLUSION: Single doses of CS-706 had significant analgesic efficacy compared with celecoxib and placebo in the relief of postoperative dental pain in the healthy subjects enrolled in this study.


Assuntos
Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Pirazóis/uso terapêutico , Pirróis/uso terapêutico , Sulfonamidas/uso terapêutico , Extração Dentária , Doença Aguda , Adolescente , Adulto , Celecoxib , Inibidores de Ciclo-Oxigenase 2/administração & dosagem , Inibidores de Ciclo-Oxigenase 2/efeitos adversos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dente Serotino/cirurgia , Medição da Dor , Pirazóis/efeitos adversos , Pirazóis/farmacologia , Pirróis/administração & dosagem , Pirróis/efeitos adversos , Sulfonamidas/administração & dosagem , Sulfonamidas/efeitos adversos , Sulfonamidas/farmacologia , Extração Dentária/efeitos adversos , Dente Impactado/cirurgia , Resultado do Tratamento
13.
Clin Pharmacokinet ; 55(6): 641-55, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26620048

RESUMO

Edoxaban, a once daily non-vitamin K antagonist oral anticoagulant, is a direct, selective, reversible inhibitor of factor Xa (FXa). In healthy subjects, single oral doses of edoxaban result in peak plasma concentrations within 1.0-2.0 h of administration, followed by a biphasic decline. Exposure is approximately dose proportional for once daily doses of 15-150 mg. Edoxaban is predominantly absorbed from the upper gastrointestinal tract, and oral bioavailability is approximately 62 %. Food does not affect total exposure to edoxaban. The terminal elimination half-life in healthy subjects ranges from 10 to 14 h, with minimal accumulation upon repeat once daily dosing up to doses of 120 mg. The steady-state volume of distribution is approximately 107 L, and total clearance is approximately 22 L/h; renal clearance accounts for approximately 50 % of total clearance, while metabolism and biliary secretion account for the remaining 50 %. Intrinsic factors, such as age, sex and race, do not affect edoxaban pharmacokinetics after renal function is taken into account. Oral administration of edoxaban results in rapid changes in anticoagulatory biomarkers, with peak effects on anticoagulation markers (such as anti-FXa), the prothrombin time and the activated partial thromboplastin time occurring within 1-2 h of dosing.


Assuntos
Anticoagulantes/farmacocinética , Inibidores do Fator Xa/farmacocinética , Piridinas/farmacocinética , Tiazóis/farmacocinética , Área Sob a Curva , Coagulação Sanguínea , Citocromo P-450 CYP3A/metabolismo , Relação Dose-Resposta a Droga , Interações Medicamentosas , Meia-Vida , Humanos , Falência Hepática/metabolismo , Taxa de Depuração Metabólica , Ligação Proteica , Insuficiência Renal/metabolismo
14.
J Clin Pharmacol ; 56(2): 203-12, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26138993

RESUMO

A population pharmacokinetic model was developed to describe plasma concentrations of mirogabalin and lactam metabolite, obtained following a single oral dose of 5 mg mirogabalin to subjects with varying degrees of renal function.A 2-compartment model was used for both mirogabalin and lactam metabolite. Body weight was a significant covariate on volume of distribution of mirogabalin and lactam metabolite, whereas creatinine clearance significantly affected both renal and nonrenal clearance of mirogabalin. The total clearance of mirogabalin was decreased by 25%, 54%, and 76% in subjects with mild, moderate, and severe renal impairment, respectively, relative to normal controls. Simulation results showed that in comparison with the normal renal function group receiving mirogabalin 15 mg once or twice daily, dose reduction by 50% or 75% in subjects with moderate or severe renal impairment would produce similar AUCss values, but 37%-43% or 28%-32% lower Cmax,ss of mirogabalin. Predicted mirogabalin AUCss was 26% higher, whereas Cmax,ss was similar in subjects with mild renal impairment compared with those having normal renal function taking the same dose. Results support a dose reduction by 50% or 75% in subjects with moderate or severe renal impairment. No dose adjustment seemed necessary for subjects with mild renal impairment.


Assuntos
Compostos Bicíclicos com Pontes/farmacocinética , Simulação por Computador , Nefropatias/metabolismo , Modelos Biológicos , Adulto , Área Sob a Curva , Compostos Bicíclicos com Pontes/administração & dosagem , Compostos Bicíclicos com Pontes/sangue , Compostos Bicíclicos com Pontes/metabolismo , Estudos de Casos e Controles , Feminino , Meia-Vida , Humanos , Masculino , Pessoa de Meia-Idade
15.
J Clin Pharmacol ; 56(1): 67-77, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26073181

RESUMO

Mirogabalin (DS-5565) is an α2δ-1 ligand being developed for pain associated with diabetic peripheral neuropathy, fibromyalgia, and postherpetic neuralgia. Nonlinear mixed-effects analyses were performed on average daily pain and on the incidence of the adverse events dizziness and somnolence. These models were used to predict the dose of mirogabalin equivalent to pregabalin and the probability of meaningful reduction in pain compared with placebo and pregabalin. In addition, regimen effects were evaluated for reductions of adverse events. Mirogabalin was estimated to be 17-fold more potent than pregabalin. The effectiveness of 150 mg pregabalin, dosed twice daily, attenuated by week 5. Therefore, the estimated mechanism-based equivalent dose (ED) of 17.7 mg mirogabalin was higher than that predicted to achieve comparable pain reduction. If attenuation of the pregabalin effect is real, mirogabalin doses lower than the ED could yield comparable pain reduction, albeit with less differentiation in pain from placebo. The incidence rate of dizziness and somnolence decreased over time. Twice-daily dosing of mirogabalin was predicted to yield a lower incidence rate of dizziness than once-daily dosing; thus, titration of dosages should reduce adverse event rates. These model results were used to influence phase 3 dosing selection.


Assuntos
Analgésicos , Compostos Bicíclicos com Pontes , Diabetes Mellitus/tratamento farmacológico , Modelos Biológicos , Neuralgia/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Analgésicos/efeitos adversos , Analgésicos/uso terapêutico , Compostos Bicíclicos com Pontes/efeitos adversos , Compostos Bicíclicos com Pontes/uso terapêutico , Distúrbios do Sono por Sonolência Excessiva/induzido quimicamente , Tontura/induzido quimicamente , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor
17.
Drugs Aging ; 31(6): 461-70, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24777691

RESUMO

BACKGROUND AND OBJECTIVES: Colesevelam significantly lowers cholesterol in patients with hypercholesterolemia, and both cholesterol and hemoglobin A1C (A1C) in patients with type 2 diabetes mellitus (T2DM). The purpose of this post hoc analysis was to evaluate the efficacy and safety/tolerability of colesevelam in older (≥65 years) and younger (<65 years) adults. METHODS: We conducted post hoc analyses of pooled clinical trial data from seven phase II and III randomized, double-blind, placebo-controlled, primary hyperlipidemia and T2DM clinical trials. The hyperlipidemia safety/tolerability analysis included seven studies (≥65 years, n = 154; <65 years, n = 381); the efficacy analysis utilized one study with sufficient patients in both age groups for meaningful comparison. The T2DM analyses included four studies (safety/tolerability: ≥65 years, n = 249; <65 years, n = 880) or three studies (efficacy). In the hyperlipidemia studies, patients received colesevelam 1.5-4.5 g/day or placebo, alone or with a statin, for 4 weeks to 6 months. In the T2DM studies, colesevelam 3.75 g/day or placebo was added to existing antidiabetes therapies for 16 or 26 weeks. Low-density lipoprotein cholesterol (LDL-C), A1C, and adverse events were assessed. RESULTS: In the hyperlipidemia analysis, colesevelam versus placebo produced similar mean reductions from baseline in LDL-C in older (-16.6 vs. +0.5 %) and younger (-13.7 vs. +0.4 %) patients. In the T2DM analysis, older and younger patients had similar reductions from baseline in A1C (treatment difference -0.59 and -0.54 %, respectively; both p < 0.001) and LDL-C (-14.7 and -15.5 %, respectively; both p < 0.001) with colesevelam. In both analyses, adverse event incidence was generally similar between subgroups. In the T2DM analysis, hypoglycemia was slightly more frequent with colesevelam versus placebo in older patients (5.8 vs. 2.3 %); no reports of hypoglycemia were considered serious adverse events. CONCLUSIONS: In primary hyperlipidemia and in T2DM, colesevelam appeared to be generally as safe, well tolerated, and efficacious in patients aged ≥65 years as in those aged <65 years.


Assuntos
Alilamina/análogos & derivados , Anticolesterolemiantes/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hiperlipidemias/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Alilamina/administração & dosagem , Alilamina/efeitos adversos , Alilamina/uso terapêutico , Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/efeitos adversos , LDL-Colesterol/sangue , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Cloridrato de Colesevelam , Relação Dose-Resposta a Droga , Esquema de Medicação , Quimioterapia Combinada , Feminino , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
J Clin Pharmacol ; 52(7): 996-1006, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21566200

RESUMO

CS-0777 is a selective sphingosine 1-phosphate receptor-1 (S1P(1)) modulator under development for treatment of autoimmune conditions. A randomized, double-blind, placebo-controlled study was conducted to assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of single oral doses of CS-0777 in escalating dose cohorts of healthy male participants (0.1, 0.3, 1.0, and 2.5 mg; 6 active, 2 placebo per cohort). Primary pharmacodynamic parameters were absolute lymphocyte counts and lymphocyte subsets (CD4 and CD8 T and B cells). CS-0777 resulted in a pronounced, dose-dependent decrease in absolute lymphocyte counts (mean percent decrease from baseline at 24 hours postdose: 7%, 26%, 52%, 79%, and 85%, for placebo and 0.1, 0.3, 1.0, and 2.5 mg, respectively). Dose-related decreases of similar magnitude were observed for T and B cell subsets. Mean total white blood cell and neutrophil counts remained within normal ranges for all dose levels. CS-0777 was well tolerated, and there were no serious or severe adverse events. Mild, asymptomatic bradycardia and transaminase elevations (<3-fold upper limit of normal), similar to findings for other S1P receptor modulators, were observed at the highest dose level (2.5 mg). Therefore, CS-0777 shows potent activity in humans and may hold potential for treatment of autoimmune conditions such as multiple sclerosis.


Assuntos
Amino Álcoois/farmacologia , Linfócitos B/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Pirróis/farmacologia , Adulto , Amino Álcoois/administração & dosagem , Amino Álcoois/efeitos adversos , Linfócitos B/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Relação Dose-Resposta a Droga , Método Duplo-Cego , Humanos , Contagem de Linfócitos , Masculino , Pirróis/administração & dosagem , Pirróis/efeitos adversos , Receptores de Lisoesfingolipídeo/efeitos dos fármacos , Receptores de Lisoesfingolipídeo/metabolismo , Adulto Jovem
19.
J Neuroimmunol ; 246(1-2): 100-7, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22465063

RESUMO

CS-0777 is a selective sphingosine 1-phosphate receptor-1 modulator under investigation for treatment of multiple sclerosis (MS). We conducted an open-label, pilot study in 25 MS patients to assess the safety, pharmacokinetics, pharmacodynamics and exploratory efficacy of oral CS-0777 (0.1, 0.3 and 0.6 mg), administered once weekly or every other week for 12 weeks. CS-0777 resulted in a pronounced, dose-dependent decrease in lymphocytes and CD4 T cell subsets, which returned to baseline within 4 weeks after the last dose. Overall, CS-0777 was safe and well-tolerated. These results require confirmation in a double-blind, placebo-controlled and adequately powered phase 2 study in MS.


Assuntos
Amino Álcoois/farmacologia , Lisofosfolipídeos/metabolismo , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/imunologia , Pirróis/farmacologia , Receptores de Lisoesfingolipídeo/metabolismo , Esfingosina/análogos & derivados , Administração Oral , Amino Álcoois/efeitos adversos , Amino Álcoois/farmacocinética , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Relação Dose-Resposta Imunológica , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/imunologia , Humanos , Subpopulações de Linfócitos/efeitos dos fármacos , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/patologia , Linfopenia/imunologia , Linfopenia/metabolismo , Linfopenia/patologia , Esclerose Múltipla/patologia , Projetos Piloto , Pirróis/efeitos adversos , Pirróis/farmacocinética , Esfingosina/metabolismo
20.
Drug Saf ; 33(8): 643-52, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20635822

RESUMO

Diabetic macular edema (DME) is the leading cause of visual loss and legal blindness in people with diabetes mellitus. The pathogenesis of DME is complex and multifactorial, and involves both local and systemic risk factors that may alter the blood-retina barrier and allow leakage of protein and fluid into the macula. Recently, in addition to well known risk factors, the use of thiazolidinediones (glitazones) has been related to the development and worsening of DME. This review is based on available literature derived from EMBASE and MEDLINE, from 1950 to May 2010, and focuses on the potential correlations between DME and current available therapies for type 1 and 2 diabetes. This review reveals that the current literature, with the potential exception of glitazones, is not sufficient for a definite statement on the association between DME and currently available diabetic therapies. In fact, among antidiabetic agents, the class of glitazones appears the only one to be potentially associated with DME. Furthermore, adequately powered, prospective studies are warranted to evaluate the exact causal association between glitazones and DME and to exclude the role of other confounding factors potentially able to induce or exacerbate macular edema. Improvement of the quality and reporting in postmarketing surveillance and the use of the 'dechallenge and rechallenge' approach in case of suspicious cause/effect drug relationship of DME are highly encouraged.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , MEDLINE , Edema Macular/epidemiologia , Tiazolidinedionas/efeitos adversos , Animais , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Humanos , Edema Macular/induzido quimicamente , Edema Macular/etiologia
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