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1.
Clin Immunol ; 191: 10-20, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29518577

RESUMO

This study evaluated the short-term effects of tofacitinib treatment on peripheral blood leukocyte phenotype and function, and the reversibility of any such effects following treatment withdrawal in healthy volunteers. Cytomegalovirus (CMV)-seropositive subjects received oral tofacitinib 10 mg twice daily for 4 weeks and were followed for 4 weeks after drug withdrawal. There were slight increases in total lymphocyte and total T-cell counts during tofacitinib treatment, and B-cell counts increased by up to 26%. There were no significant changes in granulocyte or monocyte counts, or granulocyte function. Naïve and central memory T-cell counts increased during treatment, while all subsets of activated T cells were decreased by up to 69%. T-cell subsets other than effector memory cluster of differentiation (CD)4+, activated naïve CD4+ and effector CD8+ T-cell counts and B-cell counts, normalized 4 weeks after withdrawal. Following ex vivo activation, measures of CMV-specific T-cell responses, and antigen non-specific T-cell-mediated cytotoxicity and interferon (IFN)-γ production, decreased slightly. These T-cell functional changes were most pronounced at Day 15, partially normalized while still on tofacitinib and returned to baseline after drug withdrawal. Total natural killer (NK)-cell counts decreased by 33%, returning towards baseline after drug withdrawal. NK-cell function decreased during tofacitinib treatment, but without a consistent time course across measured parameters. However, markers of NK-cell-mediated cytotoxicity, antibody-dependent cellular cytotoxicity and IFN-γ production were decreased up to 42% 1 month after drug withdrawal. CMV DNA was not detectable in whole blood, and there were no cases of herpes zoster reactivation. No new safety concerns arose. In conclusion, the effect of short-term tofacitinib treatment on leukocyte composition and function in healthy CMV+ volunteers is modest and largely reversible 4 weeks after withdrawal.


Assuntos
Inibidores de Janus Quinases/farmacologia , Leucócitos/efeitos dos fármacos , Piperidinas/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Adulto , Idoso , Artrite Reumatoide/tratamento farmacológico , Feminino , Voluntários Saudáveis , Humanos , Leucócitos/imunologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Fenótipo , Piperidinas/efeitos adversos , Pirimidinas/efeitos adversos , Pirróis/efeitos adversos , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
2.
Can J Physiol Pharmacol ; 95(9): 1009-1018, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28467859

RESUMO

Hypoxemia can be life-threatening, both acutely and chronically. Because hypoxemia causes vascular dysregulation that further restricts oxygen availability to tissue, it can be pharmacologically addressed. We hypothesized that theophylline can be safely combined with the ß2-adrenergic vasodilator bambuterol to improve oxygen availability in hypoxemic patients. Ergogenicity and hemodynamic effects of bambuterol and theophylline were measured in rats under hypobaric and normobaric hypoxia (12% O2). Feasibility in humans was assessed using randomized, double-blind testing of the influence of combined slow-release theophylline (300 mg) and bambuterol (20 mg) on adverse events (AEs), plasma K+, pulse, blood pressure, and drug interaction. Both drugs and their combination significantly improved hypoxic endurance in rats. In humans, common AEs were low K+ (<3.5 mmol/L; bambuterol: 12, theophylline: 4, combination: 13 episodes) and tremors (10, 0, 14 episodes). No exacerbation or serious AE occurred when drugs were combined. A drop in plasma K+ coincided with peak bambuterol plasma concentrations. Bambuterol increased heart rate by approximately 13 bpm. Drug interaction was present but small. We report promise, feasibility, and relative safety of combined theophylline and bambuterol as a treatment of hypoxemia in humans. Cardiac safety and blood K+ will be important safety endpoints when testing these drugs in hypoxemic subjects.


Assuntos
Hipóxia/tratamento farmacológico , Terbutalina/análogos & derivados , Teofilina/farmacologia , Adulto , Animais , Disponibilidade Biológica , Interações Medicamentosas , Feminino , Meia-Vida , Hemodinâmica/efeitos dos fármacos , Humanos , Hipóxia/sangue , Hipóxia/fisiopatologia , Masculino , Condicionamento Físico Animal , Ratos , Segurança , Terbutalina/efeitos adversos , Terbutalina/farmacocinética , Terbutalina/farmacologia , Terbutalina/uso terapêutico , Teofilina/efeitos adversos , Teofilina/farmacocinética , Teofilina/uso terapêutico , Resultado do Tratamento , Adulto Jovem
3.
Br J Clin Pharmacol ; 75(4): 966-78, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22924409

RESUMO

AIMS: To evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of edoxaban, an oral direct factor Xa inhibitor, in healthy subjects switching from warfarin. METHODS: Seventy-two subjects were randomized to edoxaban 60 mg once daily (n = 48) or matching placebo (n = 24) for 5 days at 24 h after the last dose of warfarin treatment (INR 2.0 to 3.0). Safety/tolerability was the primary outcome measure. Pharmacokinetics, INR, aPTT, anti-FXa, thrombin generation and other coagulation assays were assessed. RESULTS: Seventy-two subjects were randomized and 64 subjects received at least one dose of edoxaban (n = 43) or placebo (n = 21) after achieving a target INR of 2.0 to 3.0 on warfarin treatment. Edoxaban 60 mg administered 24 h post-warfarin appeared to be safe and well tolerated. Adverse events were similar across treatments. For bleeding-related adverse events, eight subjects tested positive for faecal occult blood, five subjects during warfarin treatment and three subjects during edoxaban treatment. The mean (SD) baseline (post-dose of warfarin) INR was 2.31 (0.193) which increased to 3.84 (0.744) over 2 h during the edoxaban treatment (P < 0.0001 vs. placebo), returning to post-warfarin baseline within 12 h. A similar time course of effects for the other coagulation assays was observed in accordance with the drugs' mechanisms of action. CONCLUSION: In this study of healthy subjects, edoxaban administered 24 h after the last dose of warfarin was safe and well tolerated with transient increases across the various coagulation assays above post-warfarin baseline levels.


Assuntos
Anticoagulantes , Inibidores do Fator Xa , Piridinas , Tiazóis , Varfarina/administração & dosagem , Administração Oral , Adolescente , Adulto , Anticoagulantes/administração & dosagem , Anticoagulantes/efeitos adversos , Anticoagulantes/farmacocinética , Anticoagulantes/farmacologia , Testes de Coagulação Sanguínea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Piridinas/administração & dosagem , Piridinas/efeitos adversos , Piridinas/farmacocinética , Piridinas/farmacologia , Tiazóis/administração & dosagem , Tiazóis/efeitos adversos , Tiazóis/farmacocinética , Tiazóis/farmacologia
5.
J Cardiovasc Pharmacol ; 60(4): 335-41, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23064240

RESUMO

The oral anticoagulant edoxaban, a factor Xa inhibitor, will likely be coadministered with digoxin in some patients with atrial fibrillation. Both drugs are substrates for P-glycoprotein. The objective of this phase 1, parallel study was to assess the effects of coadministration of both drugs on their respective pharmacokinetics (PK) and pharmacodynamics (PD). Forty-eight subjects, aged 18 to 45 years, received either edoxaban 60 mg once daily × 7 days (n = 24) or digoxin 0.25 mg twice daily × 2 days and once daily × 5 days (n = 24) and then concomitantly for 7 days. Serial blood and urine samples were collected for digoxin and edoxaban concentrations on days 7 and 14. Serial coagulation assays were measured for edoxaban on days 7 and 14. Edoxaban PK parameters demonstrated mild increases in area under the curve and peak concentrations of 9.5% and 15.6%, respectively, when coadministered with digoxin. Although digoxin PK parameters demonstrated increased area under the curve and peak concentrations of 8.3% and 28%, respectively, plasma concentrations were within the established therapeutic range. Edoxaban PD were consistent with PK. Both drugs were well tolerated alone or in combination. No clinically significant changes in PK, PD, or renal elimination were observed with concomitant administration of edoxaban and digoxin.


Assuntos
Digoxina/farmacocinética , Inibidores do Fator Xa , Piridinas/farmacocinética , Tiazóis/farmacocinética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Adolescente , Adulto , Anticoagulantes/efeitos adversos , Anticoagulantes/farmacocinética , Anticoagulantes/farmacologia , Área Sob a Curva , Cardiotônicos/efeitos adversos , Cardiotônicos/farmacocinética , Cardiotônicos/farmacologia , Estudos Cross-Over , Digoxina/efeitos adversos , Digoxina/farmacologia , Interações Medicamentosas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Piridinas/efeitos adversos , Piridinas/farmacologia , Tiazóis/efeitos adversos , Tiazóis/farmacologia , Fatores de Tempo , Adulto Jovem
6.
Clin Pharmacol Drug Dev ; 10(2): 131-143, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32255549

RESUMO

MW01-6-189WH (MW189) is a novel central nervous system-penetrant small-molecule drug candidate that selectively attenuates stressor-induced proinflammatory cytokine overproduction and is efficacious in intracerebral hemorrhage and traumatic brain injury animal models. We report first-in-human, randomized, double-blind, placebo-controlled phase 1 studies to evaluate the safety, tolerability, and pharmacokinetics (PK) of single and multiple ascending intravenous doses of MW189 in healthy adult volunteers. MW189 was safe and well tolerated in single and multiple doses up to 0.25 mg/kg, with no clinically significant concerns. The most common drug-related treatment-emergent adverse event was infusion-site reactions, likely related to drug solution acidity. No clinically concerning changes were seen in vital signs, electrocardiograms, physical or neurological examinations, or safety laboratory results. PK analysis showed dose-proportional increases in plasma concentrations of MW189 after single or multiple doses, with approximately linear kinetics and no significant drug accumulation. Steady state was achieved by dose 3 for all dosing cohorts. A pilot pharmacodynamic study administering low-dose endotoxin to induce a systemic inflammatory response was done to evaluate the effects of a single intravenous dose of MW189 on plasma cytokine levels. MW189 treatment resulted in lower levels of the proinflammatory cytokine TNF-α and higher levels of the anti-inflammatory cytokine IL-10 compared with placebo treatment. The outcomes are consistent with the pharmacological mechanism of MW189. Overall, the safety profile, PK properties, and pharmacodynamic effect support further development of MW189 for patients with acute brain injury.


Assuntos
Anti-Inflamatórios/administração & dosagem , Inflamação/tratamento farmacológico , Piperazinas/administração & dosagem , Piridazinas/administração & dosagem , Piridinas/administração & dosagem , Adulto , Anti-Inflamatórios/efeitos adversos , Anti-Inflamatórios/farmacocinética , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Piperazinas/efeitos adversos , Piperazinas/farmacocinética , Piridazinas/efeitos adversos , Piridazinas/farmacocinética , Piridinas/efeitos adversos , Piridinas/farmacocinética , Adulto Jovem
7.
Inflammation ; 44(1): 270-277, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32886268

RESUMO

Plasma gelsolin (pGSN) is the secreted isoform of an intracellular actin remodeling protein found in high concentrations in human plasma. Clinical studies demonstrate reduced pGSN concentrations in several disease states, including severe trauma, burns, and sepsis. Markedly decreased pGSN concentrations in these conditions precede and predict adverse clinical outcomes. In this study, we measured pGSN in patients with chronic granulomatous disease (CGD), a primary immunodeficiency characterized by recurrent infections and dysregulated inflammation. pGSN was quantified using a sandwich ELISA in plasma from healthy volunteers, clinically stable CGD patients, and X-linked CGD carriers and in sera from 12 CGD patients undergoing bone marrow transplantation. pGSN was also quantified in healthy volunteers challenged with intravenous endotoxin. pGSN concentrations were lower in CGD patients without active infection or systemic inflammation compared with healthy control subjects. In CGD patients undergoing bone marrow transplantation, pGSN concentrations increased significantly following successful transplant. X-linked carriers of CGD had normal pGSN. Despite reduction of pGSN in CGD patients, we did not detect significant changes in pGSN over 24 h following challenge of healthy volunteers with intravenous endotoxin (4 ng/kg) that elicited a febrile response. We describe, for the first time, significantly lower pGSN in clinically stable patients with CGD compared with age- and sex-matched healthy volunteers. Low pGSN levels in CGD patients significantly increased following bone marrow transplantation. X-linked carriers of CGD had normal pGSN. In healthy volunteers challenged with intravenous endotoxin, pGSN is not an acute phase reactant.


Assuntos
Gelsolina/sangue , Doença Granulomatosa Crônica/sangue , Doença Granulomatosa Crônica/diagnóstico , Adolescente , Adulto , Biomarcadores/sangue , Transplante de Medula Óssea/métodos , Estudos de Coortes , Endotoxinas/toxicidade , Feminino , Febre/sangue , Febre/induzido quimicamente , Febre/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
J Oral Maxillofac Surg ; 68(11): 2735-42, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20869152

RESUMO

PURPOSE: The purpose of the present study was to assess the safety and efficacy of oral diclofenac potassium liquid-filled soft gelatin capsule (DPSGC) that uses ProSorb dispersion technology (Xanodyne Pharmaceuticals, Inc, licensed from AAIPharma, Wilmington, NC), to treat adult patients with acute pain after third molar extraction. PATIENTS AND METHODS: In the present multicenter, randomized, double-blind, placebo-controlled trial, patients experiencing a baseline level of pain (≥ 50 mm on a 100-mm visual analog scale within 4 hours after surgery) were randomized to receive a single dose of DPSGC at 25, 50, or 100 mg or placebo. Pain intensity and relief were assessed for 6 hours after dosing. The efficacy endpoints included the summed pain intensity difference, total pain relief, and the median time to the onset of perceptible and meaningful pain relief (using the 2-stopwatch method). RESULTS: A total of 249 randomized patients had a significant increase in the summed pain intensity difference and total pain relief values at 3 and 6 hours across all DPSGC-treated groups compared with the placebo group (P < .0001). The onset of perceptible and meaningful pain relief was significantly faster in all DPSGC groups than in the placebo group, including the DPSGC 25-mg group (25 minutes [P = .0002] and 52 minutes [P < .0001] for perceptible and meaningful pain relief, respectively). Significantly fewer patients in the DPSGC groups required rescue medication compared with those in the placebo group (P < .0001). The global evaluation scores were significantly greater for the patients who received DPSGC than for those who received placebo (P < .0001), and more than 65% of DPSGC-treated patients rated the medication as good, very good, or excellent compared with 18% of the placebo-treated patients. DPSGC was generally well tolerated, and no serious adverse events were reported. CONCLUSIONS: The results from the present single-dose study of postoperative dental pain suggest that DPSGC offers significant pain relief compared with placebo and that the study medication provided was well tolerated by patients who required pain relief after third molar extraction.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Diclofenaco/administração & dosagem , Dente Serotino/cirurgia , Dor Pós-Operatória/tratamento farmacológico , Extração Dentária , Absorção , Administração Oral , Adolescente , Adulto , Analgésicos/uso terapêutico , Anti-Inflamatórios não Esteroides/farmacocinética , Cápsulas , Diclofenaco/farmacocinética , Método Duplo-Cego , Feminino , Seguimentos , Gelatina , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/etiologia , Medição da Dor , Satisfação do Paciente , Placebos , Segurança , Fatores de Tempo , Extração Dentária/efeitos adversos , Resultado do Tratamento , Vômito/etiologia , Adulto Jovem
9.
J Clin Pharmacol ; 59(5): 717-730, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30703258

RESUMO

Nitroxyl (HNO) is a reactive nitrogen molecule that has potential therapeutic benefits for patients with acute heart failure. The results of the first-in-human study for BMS-986231, a novel HNO donor, are reported. The aim of this sequential cohort study was to evaluate the safety, tolerability, and pharmacokinetic profile of BMS-986231 after 24- and 48-hour intravenous infusions in healthy volunteers. Eighty subjects were randomized and dosed. Seven cohorts (stratum A) received BMS-986231 0.1, 0.33, 1, 3, 5, 10, and 15 µg/kg/min or placebo, infused over 24 hours. An additional cohort (stratum B) received 10 µg/kg/min or placebo, infused over 48 hours. Adverse events (AEs) were reported for 30 days after completion of infusion. Blood/urine samples were collected at regular intervals; other parameters (blood pressure, heart rate/rhythm, cardiac index) were also assessed. Headaches were the most commonly reported drug-related AE (48%) in those who received BMS-986231, although their severity was reduced by hydration. No other significant drug-related AEs were noted. BMS-986231 was associated with dose-dependent and well-tolerated reductions in systolic and diastolic blood pressure versus baseline; cardiac index, as measured noninvasively, was increased. BMS-986231 had no clinically significant effect on heart rate/rhythm or laboratory parameters. Its mean elimination half-life was 0.7-2.5 hours. BMS-986231 was safe and well-tolerated for up to 24 hours (15 µg/kg/min) or 48 hours (10 µg/kg/min), with a favorable hemodynamic profile observed. Ongoing studies continue to evaluate the potential benefit of BMS-986231 in patients with acute heart failure.


Assuntos
Doadores de Óxido Nítrico/farmacocinética , Óxidos de Nitrogênio/farmacocinética , Adulto , Pressão Sanguínea/efeitos dos fármacos , Estudos de Coortes , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Insuficiência Cardíaca/tratamento farmacológico , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica , Humanos , Infusões Intravenosas , Masculino , Doadores de Óxido Nítrico/efeitos adversos , Doadores de Óxido Nítrico/sangue , Doadores de Óxido Nítrico/farmacologia , Óxidos de Nitrogênio/efeitos adversos , Óxidos de Nitrogênio/sangue , Óxidos de Nitrogênio/farmacologia , Adulto Jovem
10.
J Clin Pharmacol ; 48(11): 1309-22, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18974285

RESUMO

The pharmacokinetics of amlodipine and olmesartan in healthy volunteers after coadministration of amlodipine besylate and olmesartan medoxomil concomitantly as separate dosage forms and together in a fixed-dose combination tablet were characterized in 5 phase I, randomized, crossover studies. The mean steady-state pharmacokinetics of amlodipine and olmesartan were similar when olmesartan medoxomil 40 mg/day and amlodipine 10 mg/day were administered separately or concomitantly for 10 days. The total and maximum exposure to amlodipine and olmesartan after administration of fixed-dose combination amlodipine/olmesartan medoxomil 10 mg/40 mg was bioequivalent to amlodipine 10 mg plus olmesartan medoxomil 40 mg. The ratio of least squares mean and 90% confidence intervals for the area under the drug concentration-time curve from time zero to time t, from time zero to infinity, and the maximum observed plasma drug concentration of amlodipine and olmesartan fell within the prespecified range for bioequivalence (80.0% - 125.0%). The area under the drug concentration-time curve from time zero to time t, from time zero to infinity, and the maximum observed plasma drug concentration of both drugs also met the prespecified criterion for bioequivalence when the fixed-dose combination tablet was taken 30 minutes after a high-fat breakfast. Total exposure to amlodipine and olmesartan was dose-proportional after administration of olmesartan medoxomil 10 mg to 40 mg in the fixed-dose combination formulation with amlodipine 5 mg to 10 mg. From a pharmacokinetic perspective, the 2 drugs are well suited to coadministration in a fixed-dose combination.


Assuntos
Anlodipino/farmacocinética , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacocinética , Bloqueadores dos Canais de Cálcio/farmacocinética , Imidazóis/farmacocinética , Tetrazóis/farmacocinética , Adolescente , Adulto , Anlodipino/administração & dosagem , Anlodipino/efeitos adversos , Bloqueadores do Receptor Tipo 1 de Angiotensina II/administração & dosagem , Bloqueadores do Receptor Tipo 1 de Angiotensina II/efeitos adversos , Disponibilidade Biológica , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/efeitos adversos , Ensaios Clínicos Fase I como Assunto , Combinação de Medicamentos , Interações Medicamentosas , Humanos , Imidazóis/administração & dosagem , Imidazóis/efeitos adversos , Pessoa de Meia-Idade , Olmesartana Medoxomila , Ensaios Clínicos Controlados Aleatórios como Assunto , Tetrazóis/administração & dosagem , Tetrazóis/efeitos adversos , Equivalência Terapêutica , Adulto Jovem
11.
Immunopharmacol Immunotoxicol ; 30(3): 447-57, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18668392

RESUMO

Thalidomide is used to treat erythema nodosum leprosum (ENL). The events that precipitate this inflammatory reaction, which may occur in multibacillary leprosy patients, and the mechanism by which thalidomide arrest ENL, are not known. Thalidomide's ability to inhibit tumor necrosis factor alpha (TNF-alpha) in vitro has been proposed as a partial explanation of its effective treatment of ENL. In in vitro assays, thalidomide can enhance or suppress TNF-alpha. This is dependent on the stimulant used to evoke TNF-alpha; the procedure used to isolate the mononuclear cells from blood, and the predominant mononuclear cell type in the culture. To avoid artifacts that may occur during isolation of mononuclear cells from blood, we stimulated normal human blood with LPS and evaluated the effect of thalidomide and dexamethasone on TNF-alpha, and other inflammatory cytokines and biomarkers. Thalidomide suppressed interleukin 1 beta (IL-1beta) (p = 0.007), and it enhanced TNF-alpha (p = 0.007) and interleukin 10 (IL-10) (p = 0.031). Dexamethasone enhanced IL-10 (p = 0.013) and suppressed IL-1beta, TNF-alpha, interleukin 6 (IL-6), and interleukin 8 (IL-8) (p = 0.013). The two drugs did not suppress: C-reactive protein (CRP), Ig-superfamily cell-adhesion molecule 1 (ICAM 1), tumor necrosis factor receptor 1 (TNFR1), tumor necrosis factor receptor 2 (TNFR2), or amyloid A. In vitro and in vivo evidence is accumulating that TNF-alpha is not the primary cytokine targeted by thalidomide in ENL and other inflammatory conditions.


Assuntos
Imunossupressores/farmacologia , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Talidomida/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Proteína C-Reativa/metabolismo , Células Cultivadas , Dexametasona/farmacologia , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Leucócitos Mononucleares/imunologia , Masculino , Receptores do Fator de Necrose Tumoral/metabolismo , Proteína Amiloide A Sérica/metabolismo
12.
Clin Drug Investig ; 28(10): 635-43, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18783302

RESUMO

BACKGROUND AND OBJECTIVE: The calcimimetic cinacalcet lowers blood para-thyroid hormone (PTH), calcium and phosphorus levels and calcium-phosphorus product in patients with chronic kidney disease receiving dialysis. Cinacalcet is metabolized primarily through oxidative and conjugative pathways. Hepatic disease has the potential to alter cinacalcet metabolism. Thus, it is important to establish the potential for altered cinacalcet metabolism according to the level of hepatic function. This study aimed to evaluate the pharmacokinetics and pharmacodynamics of cinacalcet in subjects with different degrees of hepatic function. METHODS: This was a phase I, open-label, single-dose, parallel-group, single-centre study that included 24 subjects (six with normal hepatic function and six each with mild, moderate and severe hepatic impairment according to Child-Pugh criteria). Subjects were given a single 50 mg oral dose of cinacalcet. Blood samples were taken for pharmacokinetic (pre-dose and up to 120 hours post-dose) and pharmacodynamic (pre-dose and up to 72 hours post-dose) evaluations. Plasma concentrations of cinacalcet were determined using a validated normal phase turbo ion spray liquid chromatography-mass spectrometry/mass spectrometry assay. Serum ionized calcium levels were determined by standard biochemical measures, and PTH levels were determined using an immunometric intact PTH (iPTH) assay. The primary endpoints of the study were area under the concentration-time curve from 0 to time t (AUC(t)), AUC from 0 to infinity (AUC(infinity)) and maximum plasma concentration (C(max)). Other pharmacokinetic parameters (time to C(max) [t(max)], terminal half-life [t((1/2))(beta)], total body clearance [CL/F] and protein binding) and the effect of cinacalcet on plasma PTH and serum calcium were secondary endpoints. RESULTS: Total cinacalcet exposure (AUC(infinity)) was comparable in subjects with normal hepatic function and mild hepatic impairment. In subjects with moderate and severe hepatic impairment, mean AUC(infinity) was 2.4- and 4.2-fold higher, respectively, than in healthy subjects. Cinacalcet t((1/2))(beta) was 1.3- and 1.7-fold longer in subjects with moderate and severe hepatic impairment, respectively, compared with subjects with normal hepatic function. Mean C(max) and t(max), as well as protein binding, were similar in all groups. Consistent with the increase in cinacalcet exposure, decreases in iPTH tended to be greater and prolonged in subjects with moderate and severe hepatic impairment. In this study, cinacalcet was well tolerated. CONCLUSION: These data demonstrate that cinacalcet can be used without dose adjustment in patients with mild hepatic impairment. However, increased drug exposure observed in subjects with moderate to severe hepatic impairment indicates that iPTH and serum calcium levels should be monitored closely and physicians should be more cautious about dose titration in patients with moderate or severe hepatic impairment.


Assuntos
Hepatopatias/metabolismo , Fígado/metabolismo , Naftalenos/farmacocinética , Administração Oral , Idoso , Área Sob a Curva , Cálcio/sangue , Cromatografia Líquida de Alta Pressão/métodos , Cinacalcete , Feminino , Meia-Vida , Cefaleia/induzido quimicamente , Humanos , Imunoensaio/métodos , Hepatopatias/sangue , Hepatopatias/fisiopatologia , Masculino , Espectrometria de Massas/métodos , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Naftalenos/administração & dosagem , Naftalenos/efeitos adversos , Náusea/induzido quimicamente
13.
Clin Pharmacol Ther ; 103(5): 888-898, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28857147

RESUMO

We hypothesized that concomitant pharmacological inhibition of the endothelin and adenosine pathway is safe and improves exercise performance in hypoxic humans, via a mechanism that does not involve augmentation of blood oxygenation. To test this hypothesis, we established safety and drug interactions for aminophylline (500 mg) plus ambrisentan (5 mg) in normoxic volunteers. Subsequently, a placebo-controlled study was employed to test the combination in healthy resting and exercising volunteers at simulated altitude (4,267 m). No serious adverse events occurred. Drug interaction was minimal or absent. Aminophylline alleviated hypoxia-induced headaches. Aminophylline, ambrisentan, and their combination all significantly (P < 0.05 vs. placebo) improved submaximal hypoxic exercise performance (19.5, 20.6, and 19.1% >placebo). Single-dose ambrisentan increased blood oxygenation in resting, hypoxic subjects. We conclude that combined aminophylline and ambrisentan offer promise to safely increase exercise capacity in hypoxemic humans without relying on increasing blood oxygen availability.


Assuntos
Aminofilina/efeitos adversos , Aminofilina/uso terapêutico , Endotelinas/efeitos dos fármacos , Exercício Físico/fisiologia , Hipóxia/tratamento farmacológico , Fenilpropionatos/efeitos adversos , Fenilpropionatos/uso terapêutico , Piridazinas/efeitos adversos , Piridazinas/uso terapêutico , Adenosina/metabolismo , Adolescente , Adulto , Altitude , Método Duplo-Cego , Quimioterapia Combinada/efeitos adversos , Endotelinas/metabolismo , Feminino , Humanos , Hipóxia/metabolismo , Masculino , Pessoa de Meia-Idade , Transdução de Sinais/efeitos dos fármacos , Adulto Jovem
14.
Clin Pharmacokinet ; 46(6): 525-34, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17518511

RESUMO

OBJECTIVE: To assess the differences in the pharmacokinetics and cardiac safety of ebastine and its active metabolite, carebastine, in patients with normal and impaired renal function. METHODS: Twenty-four patients with varying degrees of renal impairment (mild, moderate or severe: n = 8 per group) and 12 healthy subjects participated in an open-label, parallel-group, multicentre study. Ebastine 20mg was administered orally once daily for 5 days. Plasma concentrations of ebastine and carebastine were determined for 24 hours on day 1 and for 72 hours on day 5 by using a validated sensitive liquid chromatography-tandem mass spectrometry assay with a minimum quantifiable limit of 0.05 ng/mL for ebastine and 1.00 ng/mL for carebastine. Renal function was assessed by measuring 24-hour creatinine clearance (CL(CR)) at baseline. Cardiac and general safety parameters were also monitored. RESULTS: The pharmacokinetics of ebastine were not modified by renal impairment. No correlation between ebastine pharmacokinetics and renal function, as expressed by CL(CR) assessed 2 days prior to dosing, was observed. Comparison of the plasma exposure and the elimination half-life of ebastine and carebastine between groups showed no significant differences. Therefore, no apparent accumulation of ebastine and carebastine occurred, and steady-state concentrations of ebastine and carebastine were predictable from single-dose pharmacokinetics for both healthy subjects and patients with renal impairment, even though the variability between the groups was large. In addition, no differences were observed in the safety of ebastine between patients with renal impairment and healthy subjects when assessing adverse events, vital signs, laboratory parameters or ECGs. CONCLUSION: Ebastine was generally well tolerated in subjects with impaired renal function. No clinically important pharmacokinetic or safety differences were observed between patients with renal impairment and healthy subjects with normal renal function.


Assuntos
Butirofenonas/farmacocinética , Antagonistas dos Receptores Histamínicos H1/farmacocinética , Piperidinas/farmacocinética , Insuficiência Renal/metabolismo , Administração Oral , Adulto , Idoso , Área Sob a Curva , Butirofenonas/administração & dosagem , Butirofenonas/efeitos adversos , Esquema de Medicação , Monitoramento de Medicamentos , Eletrocardiografia/efeitos dos fármacos , Feminino , Meia-Vida , Antagonistas dos Receptores Histamínicos H1/administração & dosagem , Antagonistas dos Receptores Histamínicos H1/efeitos adversos , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Piperidinas/administração & dosagem , Piperidinas/efeitos adversos , Insuficiência Renal/tratamento farmacológico
15.
Drugs R D ; 8(1): 43-50, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17249848

RESUMO

BACKGROUND AND OBJECTIVE: Cation-containing drugs have the potential to affect the absorption of quinolones. The current study was conducted to assess whether the bioavailability of garenoxacin was affected by administration as crushed tablets with and without concomitant enteral nutrition. METHODS: This was a randomised, open-label, three-period, single-dose, crossover study carried out in healthy male volunteers who received study treatments at a clinical facility. The study included 18 subjects (mean age 30 +/- 6 years) who were treatment-naive to garenoxacin and had a body mass index of > or =18 kg/m(2) and < or =30 kg/m(2). Subjects received garenoxacin 600 mg orally in three treatments: (A) intact tablets; (B) crushed tablets suspended in water delivered via a nasogastric (NG) tube; and (C) treatment B plus concomitant enteral feeding (Osmolite; 600 mL at 100 mL/h). Serial plasma samples were collected post-dose for pharmacokinetic analysis. Pharmacokinetic parameters were determined by noncompartmental methods. Geometric mean ratio with 90% CI for area under the concentration-time curve from time 0 extrapolated to infinity (AUC(infinity)) and maximum observed plasma concentration (C(max)) were used to assess potential effects of the different conditions of administration. Absence of an effect was concluded if the 90% CIs for the ratio of geometric means for C(max) and AUC(infinity) were within 0.7-1.43 and 0.8-1.25, respectively. The pharmacokinetics (AUC(infinity)and C(max)) and safety of garenoxacin were assessed. RESULTS: Geometric means for C(max) were 8.3, 8.5 and 8.3 microg/mL and for AUC(infinity) were 103.3, 97.2 and 93.4 microg.h/mL for treatments A, B and C, respectively. The 90% CIs for geometric mean ratios for AUC(infinity) and C(max) of garenoxacin administered as crushed tablets and crushed tablets with Osmolite via NG tube relative to intact tablets administered orally were within 0.80-1.25, suggesting that the bioavailability of garenoxacin was not affected by delivery of crushed tablets via NG tube, regardless of concomitant enteral feeding, compared with oral delivery of intact tablets. Half-life (mean range 12-13 hours) was similar for all three groups. CONCLUSIONS: The relative bioavailability of garenoxacin was not affected by administration as crushed tablets, regardless of enteral feeding. Garenoxacin can be administered as crushed tablets in the presence or absence of concomitant Osmolite.


Assuntos
Nutrição Enteral/métodos , Fluoroquinolonas/administração & dosagem , Fluoroquinolonas/farmacocinética , Administração Oral , Adolescente , Adulto , Antibacterianos/administração & dosagem , Antibacterianos/efeitos adversos , Antibacterianos/farmacocinética , Área Sob a Curva , Disponibilidade Biológica , Índice de Massa Corporal , Cromatografia Líquida , Estudos Cross-Over , Fluoroquinolonas/sangue , Meia-Vida , Cefaleia/induzido quimicamente , Humanos , Intubação Gastrointestinal , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Pós , Análise de Regressão , Comprimidos , Espectrometria de Massas em Tandem , Fatores de Tempo
16.
J Clin Pharmacol ; 57(6): 770-776, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27990643

RESUMO

Spontaneous intracranial hemorrhage (ICH) remains a devastating stroke subtype, affecting as many as 80,000 people annually in the United States and associated with extremely high mortality. In the absence of any pharmacological interventions demonstrated to improve outcome, care for patients with ICH remains largely supportive. Thus, despite advances in the understanding of ICH and brain injury, there remains an unmet need for interventions that improve neurologic recovery and outcomes. Recent research suggesting inflammation and APOE genotype play a role in modifying neurologic outcome after brain injury has led to the development of an APOE-derived peptide agent (CN-105). Preclinical studies have demonstrated that CN-105 effectively downregulates the inflammatory response in acute brain injury, including ICH. Following Investigational New Drug (IND) enabling studies in murine models, this first-in-human single escalating dose and multiple dose placebo-controlled clinical trial was performed to define the safety and pharmacokinetics (PK) of CN-105. A total of 48 subjects (12 control, 36 active) were randomized in this study; all subjects completed the study. No significant safety issues were identified with both dosing regimens, and PK analysis revealed linearity without significant drug accumulation. The median half-life in the terminal elimination phase of CN-105 following a single or repeated dosing regimen did not change (approximately 3.6 hours). With the PK and preliminary safety of CN-105 established, the drug is now poised to begin first-in-disease phase 2 clinical trials in patients with ICH who urgently need new therapeutic options.


Assuntos
Anti-Inflamatórios/farmacocinética , Fármacos Neuroprotetores/farmacocinética , Adulto , Anti-Inflamatórios/efeitos adversos , Anti-Inflamatórios/sangue , Anti-Inflamatórios/urina , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Humanos , Masculino , Fármacos Neuroprotetores/efeitos adversos , Fármacos Neuroprotetores/sangue , Fármacos Neuroprotetores/urina
17.
Thromb Haemost ; 117(2): 238-245, 2017 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-27853809

RESUMO

Of the new direct oral anticoagulants, direct factor Xa inhibitors are limited by the absence of a proven reversal agent. We assessed the safety, tolerability and impact on anticoagulation reversal of ciraparantag (PER977) alone and following a 60 mg dose of the FXa inhibitor edoxaban. Escalating, single IV doses of ciraparantag were administered alone and following a 60 mg oral dose of edoxaban in a double-blind, placebo-controlled fashion to healthy subjects. Serial assessments of the pharmacokinetics and pharmacodynamic effects of ciraparantag were performed. Eighty male subjects completed the study. Following edoxaban (60 mg), a single IV dose of ciraparantag (100 to 300 mg) demonstrated full reversal of anticoagulation within 10 minutes and sustained for 24 hours. Fibrin diameter within clots was restored to normal 30 minutes after a single dose of 100 to 300 mg ciraparantag as determined by scanning electron microscopy and change in fibrin diameter quantified by automated image analysis. Potentially related adverse events were periorbital and facial flushing and cool sensation following IV injection of ciraparantag. Renal excretion of ciraparantag metabolite was the main elimination route. There was no evidence of procoagulant activity following ciraparantag as assessed by D-dimer, prothrombin fragments 1.2, and tissue factor pathway inhibitor levels. In conclusion, ciraparantag in healthy subjects is safe and well tolerated with minor, non-dose limiting adverse events. Baseline haemostasis was restored from the anticoagulated state with doses of 100 to 300 mg ciraparantag within 10-30 minutes of administration and sustained for at least 24 hours.


Assuntos
Arginina/análogos & derivados , Coagulação Sanguínea/efeitos dos fármacos , Inibidores do Fator Xa/administração & dosagem , Piperazinas/administração & dosagem , Piridinas/administração & dosagem , Tiazóis/administração & dosagem , Administração Oral , Adulto , Arginina/administração & dosagem , Arginina/efeitos adversos , Arginina/farmacocinética , Método Duplo-Cego , Monitoramento de Medicamentos/métodos , Inibidores do Fator Xa/efeitos adversos , Humanos , Injeções Intravenosas , Masculino , North Carolina , Piperazinas/efeitos adversos , Piperazinas/farmacocinética , Piridinas/efeitos adversos , Tiazóis/efeitos adversos , Tempo de Coagulação do Sangue Total
19.
J Nucl Med ; 56(11): 1793-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26315828

RESUMO

UNLABELLED: Intraarterial microdosing (IAM) is a novel drug development approach combining intraarterial drug delivery and microdosing. We aimed to demonstrate that IAM leads to target exposure similar to that of systemic full-dose administration but with minimal systemic exposure. IAM could enable the safe, inexpensive, and early study of novel drugs at the first-in-human stage and the study of established drugs in vulnerable populations. METHODS: Insulin was administered intraarterially (ipsilateral femoral artery) or systemically to 8 CD IGS rats just before blood sampling or 60-min (18)F-FDG uptake PET imaging of ipsilateral and contralateral leg muscles (lateral gastrocnemius) and systemic muscles (spinotrapezius). The (18)F-FDG uptake slope analysis was used to compare the interventions. Plasma levels of insulin and glucose were compared using area under the curve calculated by the linear trapezoidal method. A physiologically based computational pharmacokinetics/pharmacodynamics model was constructed to simulate the relationship between the administered dose and response over time. RESULTS: (18)F-FDG slope analysis found no difference between IAM and systemic full-dose slopes (0.0066 and 0.0061, respectively; 95% confidence interval [CI], -0.024 to 0.029; P = 0.7895), but IAM slope was statistically significantly greater than systemic microdose (0.0018; 95% CI, -0.045 to -0.007; P = 0.0147) and sham intervention (-0.0015; 95% CI, 0.023-0.058; P = 0.0052). The pharmacokinetics/pharmacodynamics data were used to identify model parameters that describe membrane insulin binding and glucose-insulin dynamics. CONCLUSION: Target exposure after IAM was similar to systemic full dose administration but with minimal systemic effects. The computational pharmacokinetics/pharmacodynamics model can be generalized to predict whole-body response. Findings should be validated in larger, controlled studies in animals and humans using a range of targets and classes of drugs.


Assuntos
Fluordesoxiglucose F18/administração & dosagem , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/administração & dosagem , Algoritmos , Animais , Glicemia/metabolismo , Simulação por Computador , Sistemas de Liberação de Medicamentos , Fluordesoxiglucose F18/efeitos adversos , Fluordesoxiglucose F18/farmacocinética , Hipoglicemiantes/farmacologia , Interpretação de Imagem Assistida por Computador , Injeções Intra-Arteriais , Insulina/sangue , Insulina/farmacologia , Masculino , Modelos Estatísticos , Compostos Radiofarmacêuticos/efeitos adversos , Compostos Radiofarmacêuticos/farmacocinética , Ratos
20.
Clin Pharmacokinet ; 43(2): 121-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14748620

RESUMO

OBJECTIVE: To assess the differences between patients with hepatic insufficiency and healthy subjects with regard to the pharmacokinetics, cardiac safety and overall safety of ebastine and its active metabolite carebastine. DESIGN: Open-label parallel-group study. PARTICIPANTS: 24 patients with varying degrees of hepatic insufficiency, as categorised by the Child-Pugh classification, and 12 healthy volunteers. METHODS: Healthy subjects and patients with Child-Pugh class A (n = 8) or B (n = 8) received ebastine 20 mg once daily for 7 days. Patients with Child-Pugh class C (n = 8) [single or repeated dose] received ebastine 10 mg. Plasma concentrations of ebastine and carebastine were determined for 23.5 hours following the initial dose on day 1 and for 96 hours following the dose on day 7 by using a sensitive liquid chromatography-tandem mass spectrometry assay with a minimum quantifiable limit of 0.05 microg/L for ebastine and 1.00 microg/L for carebastine. Hepatic function was assessed by blood clearance of indocyanine green 0.5 mg/kg administered intravenously on day 2. Cardiac and overall safety parameters were monitored. RESULTS: Overall, the pharmacokinetics of ebastine were not modified by hepatic impairment. No correlation between ebastine pharmacokinetics and hepatic function, as expressed by indocyanine green clearance, was observed. Comparison of the effective half-life of ebastine and carebastine between groups did not show relevant differences. Therefore, no apparent accumulation of ebastine occurred, and steady-state concentrations of ebastine and carebastine were predictable from single-dose pharmacokinetics both in healthy subjects and in hepatically impaired patients. Finally, no apparent difference was noted in the safety of ebastine between patients with hepatic insufficiency and healthy subjects as assessed by evaluation of adverse events, vital signs and laboratory parameters. CONCLUSION: Ebastine can be safely administered to patients with impaired hepatic function, as no clinically important differences can be anticipated from the pharmacokinetics and safety profile of ebastine/carebastine as compared with healthy subjects. Nevertheless, the dosage used in severely impaired patients (10mg daily) was half that used in patients with mild to moderate impairment, and any comedication did not include drugs affecting liver function; in clinical practice, both these factors should be taken into account.


Assuntos
Butirofenonas/farmacocinética , Antagonistas dos Receptores Histamínicos H1/farmacocinética , Hepatopatias/tratamento farmacológico , Piperidinas/farmacocinética , Adulto , Área Sob a Curva , Butirofenonas/efeitos adversos , Butirofenonas/metabolismo , Butirofenonas/uso terapêutico , Estudos de Casos e Controles , Feminino , Meia-Vida , Antagonistas dos Receptores Histamínicos H1/efeitos adversos , Antagonistas dos Receptores Histamínicos H1/uso terapêutico , Humanos , Absorção Intestinal , Hepatopatias/classificação , Hepatopatias/metabolismo , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Piperidinas/efeitos adversos , Piperidinas/metabolismo , Piperidinas/uso terapêutico
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