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1.
Gastroenterology ; 160(7): 2354-2366.e11, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33667488

RESUMO

BACKGROUND & AIMS: A large unmet therapeutic need exists in inflammatory bowel disease (IBD). Inhibition of interleukin (IL)-6 appears to be effective, but the therapeutic benefit of a complete IL6/IL6 receptor (IL6R) blockade is limited by profound immunosuppression. Evidence has emerged that chronic proinflammatory activity of IL6 is mainly mediated by trans-signaling via a complex of IL6 bound to soluble IL6R engaging the gp130 co-receptor without the need for membrane-bound IL6R. We have developed a decoy protein, sgp130Fc, that exclusively blocks IL6 proinflammatory trans-signaling and has shown efficacy in preclinical models of IBD, without signs of immunosuppression. METHODS: We present a 12-week, open-label, prospective phase 2a trial (FUTURE) in 16 patients with active IBD treated with the trans-signaling inhibitor olamkicept (sgp130Fc) to assess the molecular mechanisms, safety, and effectiveness of IL6 trans-signaling blockade in vivo. We performed in-depth molecular profiling at various timepoints before and after therapy induction to identify the mechanism of action of olamkicept. RESULTS: Olamkicept was well tolerated and induced clinical response in 44% and clinical remission in 19% of patients. Clinical effectiveness coincided with target inhibition (reduction of phosphorylated STAT3) and marked transcriptional changes in the inflamed mucosa. An olamkicept-specific transcriptional signature, distinguishable from remission signatures of anti-tumor necrosis factor (infliximab) or anti-integrin (vedolizumab) therapies was identified. CONCLUSIONS: Our data suggest that blockade of IL6 trans-signaling holds great promise for the therapy of IBD and should undergo full clinical development as a new immunoregulatory therapy for IBD. (EudraCT no., Nu 2016-000205-36).


Assuntos
Colite Ulcerativa/tratamento farmacológico , Doença de Crohn/tratamento farmacológico , Interleucina-6/antagonistas & inibidores , Proteínas Recombinantes de Fusão/farmacologia , Transdução de Sinais/efeitos dos fármacos , Adulto , Idoso , Colite Ulcerativa/imunologia , Doença de Crohn/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Receptores de Interleucina-6/metabolismo , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
2.
Clin Ther ; 40(5): 741-751, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29699852

RESUMO

PURPOSE: Somatropin, used to treat growth hormone deficiency, has been traditionally administered by subcutaneous (SC) injection with needle and syringe. Needle-free devices offer ease of administration and may improve adherence and outcomes. This study evaluated the relative bioavailability of somatropin delivered with a needle-free device compared with traditional SC injection. METHODS: In this randomized, single-dose, crossover study, healthy adults aged 18 to 35 years received single 4-mg doses of somatropin via a needle-free device or SC injection, along with octreotide to suppress endogenous growth hormone production. Blood samples were analyzed for serum somatropin and insulin-like growth factor-1 (IGF-1) concentrations over 24 hours after somatropin dosing. Pharmacokinetic and pharmacodynamic parameters were evaluated by using noncompartmental methods, and bioequivalence was determined based on ln transformation of the AUC0-24, AUC0-∞, Cmax, area under the effect-time curve from time 0 to 24 hours (AUEC0-24), and maximum effect concentration (Emax). Bioequivalence was concluded if the 90% CIs of the needle-free device compared with the SC injection, constructed by using the two 1-sided hypotheses at the α = 0.05 level, for these pharmacokinetic/pharmacodynamic parameters fell within the 80.00% to125.00% regulatory acceptance range. FINDINGS: A total of 57 subjects completed both study periods and were included in the pharmacokinetic analyses. Point estimates (90% CIs) of the geometric mean ratio (needle-free device/SC injection) based on serum somatropin were 1.013 (0.987-1.040) for AUC0-24, 1.012 (0.986-1.038) for AUC0-∞, and 1.200 (1.137-1.267) for Cmax. For IGF-1, baseline-corrected point estimates (90% CIs) were 0.901 (0.818-0.993) for AUEC0-24 and 0.867 (0.795-0.946) for Emax. Non-baseline-corrected values were 0.978 (0.953-1.004) for AUEC0-24 and 0.953 (0.923-0.984) for Emax. Both treatments were well tolerated; blood glucose levels increased in nearly all subjects (98.3%). All adverse events were mild and resolved spontaneously within 24 hours. IMPLICATIONS: Bioequivalence was shown for a single 4-mg dose of somatropin delivered by using a needle-free device compared with SC injection based on ln-transformed AUC0-24 and AUC0-∞ but not ln-transformed Cmax.


Assuntos
Hormônio do Crescimento Humano/farmacocinética , Fator de Crescimento Insulin-Like I/metabolismo , Octreotida/farmacologia , Adolescente , Adulto , Área Sob a Curva , Disponibilidade Biológica , Estudos Cross-Over , Feminino , Humanos , Injeções Subcutâneas , Masculino , Agulhas , Seringas , Equivalência Terapêutica , Adulto Jovem
3.
Clin Drug Investig ; 37(9): 873-879, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28660498

RESUMO

BACKGROUND AND OBJECTIVES: Degarelix is a gonadotropin-releasing hormone antagonist registered for the treatment of advanced hormone-dependent prostate cancer. Treatment causing androgen deprivation is associated with QT prolongation and this study investigated whether degarelix at supratherapeutic concentrations has an intrinsic effect per se on cardiac repolarisation and the QT interval. METHODS: This was a single-centre, randomised, crossover study comparing the effect of degarelix, placebo, and the positive control moxifloxacin on the QT interval. Degarelix and placebo treatments were double-blind, whereas moxifloxacin treatment was open-label. Eighty healthy men, aged 18-45 years, received single intravenous doses of degarelix 2.8 mg, and placebo, as well as a single oral dose of moxifloxacin 400 mg. Electrocardiograms were collected up to 24 h after the start of administration, with the QT interval assessed and plasma concentrations of degarelix concomitantly analysed. RESULTS: Time-matched, one-sided 95% upper confidence boundaries for baseline-corrected average changes from placebo for the QT interval, corrected using the Fridericia method (ΔΔQTcF), did not exceed 10 ms at any timepoint, with maximum degarelix concentrations reaching approximately threefold the concentrations seen in the treatment of prostate cancer. Furthermore, concentration-exposure analysis indicated absence of any QT prolongation effects of degarelix. No significant effect on any other cardiac parameter was observed. The lower bound of the 98.3% confidence interval for moxifloxacin ΔΔQTcF exceeded 5 ms, thus verifying assay sensitivity. CONCLUSION: The results showed that the study was validated to detect a significant effect on the QT interval, and that degarelix by itself does not have any effect on the QT interval and cardiac repolarisation at supratherapeutic concentrations.


Assuntos
Síndrome do QT Longo/induzido quimicamente , Oligopeptídeos/efeitos adversos , Receptores LHRH/antagonistas & inibidores , Adolescente , Adulto , Estudos Cross-Over , Método Duplo-Cego , Eletrocardiografia , Fluoroquinolonas/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Moxifloxacina , Adulto Jovem
4.
Clin Pharmacol Ther ; 74(5): 423-36, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14586383

RESUMO

OBJECTIVE: Our objective was to investigate the main in vivo transport mechanisms of fexofenadine involved in the intestinal absorption and bioavailability of the drug in humans. METHODS: A jejunal single-pass perfusion study was performed in 10 healthy volunteers. Each experiment lasted for 200 minutes and was divided into 2 periods of 100 minutes. During the control period (0-100 minutes), the jejunal segment was perfused with 100 mg/L (186-micromol/L) fexofenadine. In the treatment period (100-200 minutes), fexofenadine was coperfused with 500 mg/L (1018-micromol/L) of the membrane transport inhibitor verapamil. The concentrations of fexofenadine in the perfusate and plasma were measured by HPLC with ultraviolet and mass detection, respectively. RESULTS: Verapamil did not significantly affect the human effective jejunal permeability of fexofenadine. The mean (+/-SD) effective jejunal permeability values were 0.06 +/- 0.07. 10(-4) cm/s and 0.04 +/- 0.07. 10(-4) cm/s in the control and treatment periods, respectively. However, verapamil increased the apparent absorption rate constant into the systemic circulation and the area under the plasma concentration-time curve for fexofenadine from 0.0030 +/- 0.0012 min(-1) to 0.0255 +/- 0.0103 min(-1) (P <.001) and from 161 +/- 181 ng/mL x min to 664 +/- 537 ng/mL x min (P <.01), respectively. CONCLUSIONS: In this in vivo perfusion study verapamil increased the bioavailability of fexofenadine. Because the permeability, which is a direct measure of intestinal transport, was unchanged, we suggest that the major reason for this effect was decreased first-pass liver extraction of fexofenadine. The most plausible mechanism is either decreased organic anion transporting polypeptide-mediated sinusoidal uptake or P-glycoprotein-mediated canalicular secretion of fexofenadine, or both.


Assuntos
Antialérgicos/farmacocinética , Absorção Intestinal , Proteínas de Membrana Transportadoras/metabolismo , Terfenadina/análogos & derivados , Terfenadina/farmacocinética , Adulto , Algoritmos , Área Sob a Curva , Disponibilidade Biológica , Bloqueadores dos Canais de Cálcio/farmacologia , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Técnicas In Vitro , Absorção Intestinal/efeitos dos fármacos , Intestinos/irrigação sanguínea , Jejuno/irrigação sanguínea , Jejuno/metabolismo , Masculino , Moduladores de Transporte de Membrana , Proteínas de Membrana Transportadoras/antagonistas & inibidores , Fluxo Sanguíneo Regional/fisiologia , Espectrofotometria Ultravioleta , Verapamil/farmacologia
5.
J Clin Pharmacol ; 51(5): 770-83, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20663994

RESUMO

The biliary excretion of the oral thrombin inhibitor ximelagatran and its metabolites was investigated by using duodenal aspiration in healthy volunteers following intraintestinal dosing. In the first investigation, radiolabeled [(14)C]ximelagatran was administered, enabling quantification of the biliary excretion and identification of metabolites in the bile. In the second study, the effect of erythromycin on the biliary clearance of ximelagatran and its metabolites was investigated to clarify the reported ximelagatran-erythromycin interaction. Approximately 4% of the intraintestinal dose was excreted into bile with ximelagatran and its active form, melagatran, being the most abundant compounds. Four novel ximelagatran metabolites were identified in bile (<0.1% of dose). Erythromycin changed the pharmacokinetics of ximelagatran and its metabolites, with an elevated ximelagatran (78% increase), OH-melagatran (89% increase), and melagatran (86% increase) plasma exposure and higher peak plasma concentrations of the compounds being measured. In parallel, the biliary clearance was moderately reduced. The results suggest that inhibition of hepatobiliary transport is a likely mechanism for the interaction between erythromycin and ximelagatran. Furthermore, the study demonstrated the value of direct bile sampling in humans for the identification of primary biliary metabolites.


Assuntos
Antibacterianos/farmacologia , Antitrombinas/farmacocinética , Azetidinas/farmacocinética , Benzilaminas/farmacocinética , Bile/metabolismo , Eritromicina/farmacologia , Adulto , Antibacterianos/administração & dosagem , Antitrombinas/administração & dosagem , Área Sob a Curva , Azetidinas/administração & dosagem , Benzilaminas/administração & dosagem , Biotransformação , Estudos Cross-Over , Duodeno/metabolismo , Eritromicina/administração & dosagem , Feminino , Meia-Vida , Humanos , Intubação Gastrointestinal , Masculino , Taxa de Depuração Metabólica , Modelos Biológicos , Suécia , Adulto Jovem
6.
Drug Metab Dispos ; 34(7): 1182-9, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16621934

RESUMO

The aim of this study in pigs was to investigate the local pharmacokinetics of fexofenadine in the intestine and liver by using the pig as a model for drug transport in the entero-hepatobiliary system. A parallel group design included seven pigs (10-12 weeks, 22.2-29.5 kg) in three groups (G1, G2, G3), and a jejunal single-pass perfusion combined with sampling from the bile duct and the portal, hepatic, and superior caval veins was performed. Fexofenadine was perfused through the jejunal segment alone (G1: 120 mg/l, total dose 24 mg) or with two different verapamil doses (G2: 175 mg/l, total dose 35 mg; and G3: 1000 mg/l, total dose 200 mg). The animals were fully anesthetized and monitored throughout the experiment. Fexofenadine had a low liver extraction (E(H); mean +/- S.E.M.), and the given doses of verapamil did not affect the E(H) (0.13 +/- 0.04, 0.16 +/- 0.03, and 0.12 +/- 0.02 for G1, G2, and G3, respectively) or biliary clearance. The E(H) for verapamil and antipyrine agreed well with human in vivo data. Verapamil did not increase the intestinal absorption of fexofenadine, even though the jejunal permeability of fexofenadine, verapamil, and antipyrine showed a tendency to increase in G2. This combined perfusion and hepatobiliary sampling method showed that verapamil did not affect the transport of fexofenadine in the intestine or liver. In this model the E(H) values for both verapamil and antipyrine were similar to the corresponding values in vivo in humans.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Antagonistas dos Receptores Histamínicos H1/farmacocinética , Absorção Intestinal/efeitos dos fármacos , Fígado/efeitos dos fármacos , Terfenadina/análogos & derivados , Verapamil/farmacologia , Animais , Antipirina/farmacocinética , Bile/metabolismo , Relação Dose-Resposta a Droga , Antagonistas dos Receptores Histamínicos H1/sangue , Fígado/metabolismo , Modelos Animais , Perfusão , Suínos , Terfenadina/sangue , Terfenadina/farmacocinética
7.
Pharm Res ; 21(8): 1398-404, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15359574

RESUMO

PURPOSE: To investigate the membrane transport mechanisms of fexofenadine in the Caco-2 model. METHODS: Transport studies were performed in Caco-2 cell monolayers 21-25 days after seeding. The apparent permeability (Papp) of fexofenadine was determined in the concentration range 10-1000 microM in the basolateral-to-apical (b-a) and 50-1000 microM in the apical-to-basolateral (a-b) direction. The concentration-dependent effects of various inhibitors of P-glycoprotein (P-gp) (GF120918, ketoconazole, verapamil, erythromycin), multidrug resistant associated protein (MRP) (indomethacin, probenecid), and organic anion transporting polypeptide (OATP) (rifamycin SV) on the bidirectional transport of 150 microM fexofenadine were also examined. RESULTS: Fexofenadine displayed polarized transport, with the Pappb-a being 28- to 85-fold higher than the Papp(a-b). The Papp(a-b) was independent of the concentration applied, whereas Pappb-a decreased with increasing concentration (Vmax = 5.21 nmol cm(-2)s(-1) and K(M) = 150 microM), suggesting saturation of an apical efflux transporter. All four P-gp inhibitors had a strong, concentration-dependent effect on the Papp of fexofenadine in both directions, with GF 120918 being the most specific among them. The IC50 of verapamil was 8.44 microM on the P-gp-mediated secretion of fexofenadine. The inhibitors of OATP or MRP appeared not to affect the Papp(a-b) of fexofenadine in the Caco-2 model. CONCLUSIONS: This study clearly indicates that P-gp was the main transport protein of fexofenadine in the Caco-2 model. Even though P-gp was completely inhibited, fexofenadine was predicted to have a low fraction dose absorbed in humans due to poor intestinal permeability, and low passive diffusion seems to be the major absorption mechanism.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores , Células CACO-2/metabolismo , Terfenadina/análogos & derivados , Terfenadina/farmacocinética , Transporte Biológico/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Difusão , Humanos , Concentração Inibidora 50 , Cinética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Transportadores de Ânions Orgânicos/antagonistas & inibidores , Permeabilidade
8.
Drug Metab Dispos ; 31(6): 805-13, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12756216

RESUMO

For the first time the human intestinal effective permeability, estimated from the luminal disappearance and intestinal metabolism of phytochemicals, sulforaphane and quercetin-3,4'-glucoside, as well as the simultaneous changes in gene expression in vivo in enterocytes, has been studied in the human jejunum in vivo (Loc-I-Gut). Both compounds as components of an onion and broccoli extract could readily permeate the enterocytes in the perfused jejunal segment. At the physiologically relevant, dietary concentration tested, the average effective jejunal permeability (Peff) and percentage absorbed (+/- S.D.) were 18.7 +/- 12.6 x 10-4 cm/s and 74 +/- 29% for sulforaphane and 8.9 +/- 7.1 x 10-4 cm/s and 60 +/- 31% for quercetin-3,4'-diglucoside, respectively. Furthermore, a proportion of each compound was conjugated and excreted back into the lumen as sulforaphane-glutathione and quercetin-3'-glucuronide. The capacity of the isolated segment to deconjugate quercetin from quercetin-3,4'-diglucoside during the perfusion was much higher than the beta-glucosidase activity of the preperfusion jejunal contents, indicating that the majority (79-100%) of the beta-glucosidase capacity derives from the enterocytes in situ. Simultaneously, we determined short-term changes in gene expression in exfoliated enterocytes, which showed 2.0 +/- 0.4-fold induction of glutathione transferase A1 (GSTA1) mRNA (p < 0.002) and 2.4 +/- 1.2-fold induction of UDP-glucuronosyl transferase 1A1 (UGT1A1) mRNA (p < 0.02). The changes in gene expression were also seen in differentiated Caco-2 cells, where sulforaphane was responsible for induction of GSTA1 and quercetin for induction of UGT1A1. These results show that food components have the potential to modify drug metabolism in the human enterocyte in vivo very rapidly.


Assuntos
Brassica , Jejuno/metabolismo , Cebolas , Quercetina/farmacocinética , Tiocianatos/farmacocinética , Células CACO-2/enzimologia , Células CACO-2/metabolismo , Cromatografia Líquida , Enterócitos/enzimologia , Enterócitos/metabolismo , Interações Alimento-Droga , Expressão Gênica , Glucuronídeos/metabolismo , Glucuronosiltransferase/biossíntese , Glutationa/análogos & derivados , Glutationa/metabolismo , Glutationa Transferase/biossíntese , Humanos , Absorção Intestinal , Isotiocianatos , Jejuno/enzimologia , Espectrometria de Massas , Extratos Vegetais/farmacocinética , Caules de Planta , Tubérculos , Quercetina/análogos & derivados , Quercetina/metabolismo , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sulfóxidos , beta-Glucosidase/biossíntese
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