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1.
Cell Metab ; 34(9): 1234-1247.e9, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35985340

RESUMO

With an increasing prevalence of obesity, there is a need for new therapies to improve body weight management and metabolic health. Multireceptor agonists in development may provide approaches to fulfill this unmet medical need. LY3437943 is a novel triple agonist peptide at the glucagon receptor (GCGR), glucose-dependent insulinotropic polypeptide receptor (GIPR), and glucagon-like peptide-1 receptor (GLP-1R). In vitro, LY3437943 shows balanced GCGR and GLP-1R activity but more GIPR activity. In obese mice, administration of LY3437943 decreased body weight and improved glycemic control. Body weight loss was augmented by the addition of GCGR-mediated increases in energy expenditure to GIPR- and GLP-1R-driven calorie intake reduction. In a phase 1 single ascending dose study, LY3437943 showed a safety and tolerability profile similar to other incretins. Its pharmacokinetic profile supported once-weekly dosing, and a reduction in body weight persisted up to day 43 after a single dose. These findings warrant further clinical assessment of LY3437943.


Assuntos
Glucagon , Receptores dos Hormônios Gastrointestinais , Animais , Peso Corporal , Polipeptídeo Inibidor Gástrico/metabolismo , Glucagon/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Controle Glicêmico , Camundongos , Camundongos Obesos , Receptores dos Hormônios Gastrointestinais/metabolismo , Receptores de Glucagon/metabolismo , Redução de Peso
2.
Adv Ther ; 39(1): 488-503, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34787823

RESUMO

INTRODUCTION: This study evaluated the pharmacokinetics, pharmacodynamics, and safety of a single dulaglutide dose in Chinese healthy subjects and of multiple dulaglutide doses in Chinese patients with type 2 diabetes mellitus (T2DM). METHODS: This two-part, double-blind, placebo-controlled study included 16 healthy subjects randomized to receive a single dose of placebo and two of three dulaglutide doses (0.5 mg, 0.75 mg, or 1.5 mg) in three treatment periods, and 42 patients with T2DM randomized to receive placebo or one of the three dulaglutide doses once weekly for 4 weeks. Pharmacokinetics and safety parameters were assessed in all participants, and pharmacodynamics effects were investigated in patients with T2DM. RESULTS: Following a single-dose administration of 0.5 mg, 0.75 mg, or 1.5 mg dulaglutide in healthy subjects, geometric mean maximum concentrations (Cmax) were 29.4, 44.2, and 81.5 ng/mL, respectively. Following weekly administration in patients with T2DM for 4 weeks, Cmax were 26.3, 41.4, and 70.2 ng/mL, respectively, with accumulation ratios of 1.33-1.39. Geometric mean for half-life of 4-5 days and median time to Cmax (tmax) of approximately 48 h were observed in both study populations. Dose-proportional increases in drug exposure were observed after both single and multiple dosing. Significant reductions in baseline-corrected fasting glucose and hemoglobin A1c (HbA1c) were observed in patients with T2DM who received dulaglutide 0.75 mg and 1.5 mg. Dulaglutide was well tolerated, with the majority of adverse events being gastrointestinal disorders of mild severity. CONCLUSIONS: Pharmacokinetics, pharmacodynamics, and safety profiles of dulaglutide demonstrated in the present study support a once-weekly dosing regimen in Chinese patients with T2DM. TRIAL REGISTRATION: NCT01667900 (ClinicalTrials.gov).


Assuntos
Diabetes Mellitus Tipo 2 , Peptídeos Semelhantes ao Glucagon , Fragmentos Fc das Imunoglobulinas , Proteínas Recombinantes de Fusão , Glicemia , China , Diabetes Mellitus Tipo 2/tratamento farmacológico , Relação Dose-Resposta a Droga , Método Duplo-Cego , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Voluntários Saudáveis , Humanos , Hipoglicemiantes/efeitos adversos , Fragmentos Fc das Imunoglobulinas/efeitos adversos , Proteínas Recombinantes de Fusão/efeitos adversos
3.
Clin Pharmacokinet ; 60(8): 1049-1059, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33778934

RESUMO

BACKGROUND AND AIMS: The pharmacokinetics (PK) and single-dose tolerability of tirzepatide, a dual glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist being developed for once-weekly treatment of type 2 diabetes (T2D), weight management, and nonalcoholic steatohepatitis, was evaluated in subjects with renal impairment versus healthy subjects with normal renal function. METHODS: Forty-five subjects, categorized by baseline renal status, i.e. mild (n = 8, estimated glomerular filtration rate [eGFR] 60-89 mL/min/1.73m2), moderate (n = 8, eGFR 30-59 mL/min/1.73m2), severe renal impairment (n = 7, eGFR < 30 mL/min/1.73m2), end-stage renal disease requiring dialysis (n = 8), and normal renal function (n = 14, eGFR ≥ 90 mL/min/1.73m2), received a single subcutaneous dose of tirzepatide 5 mg. Tirzepatide plasma concentrations up to 648 h postdose were measured to compute PK parameters. The primary analysis evaluated the ratios of area under the plasma concentration-time curves (AUCs) and maximum plasma drug concentration (Cmax) of renal impairment versus the normal renal function group (90% confidence interval [CI]). In addition, the relationship between PK parameters and continuous variables of renal function was assessed by linear regression. RESULTS: Tirzepatide exposure was similar across renal impairment groups and healthy subjects. The 90% CI of ratios of AUCs and Cmax comparing each renal impairment group versus normal renal function spanned unity, except for a 25-29% increase in AUCs in the moderate renal impairment group. There was no significant relationship between tirzepatide exposure and eGFR. Few adverse events were reported across the renal impairment and normal renal function groups. The majority were mild in severity and of a gastrointestinal nature in the renal impairment groups. CONCLUSION: There were no clinically relevant effects of renal impairment on tirzepatide PK. Dose adjustment may not be required for patients with renal impairment. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT03482024.


Assuntos
Diabetes Mellitus Tipo 2 , Preparações Farmacêuticas , Área Sob a Curva , Diabetes Mellitus Tipo 2/tratamento farmacológico , Polipeptídeo Inibidor Gástrico , Receptor do Peptídeo Semelhante ao Glucagon 1 , Humanos
4.
Diabetes Obes Metab ; 22(10): 1886-1891, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32519795

RESUMO

The effect of dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist (RA) tirzepatide on gastric emptying (GE) was compared to that of GLP-1RAs in non-clinical and clinical studies. GE was assessed following acute and chronic treatment with tirzepatide in diet-induced obese mice versus semaglutide or long-acting GIP analogue alone. Participants [with and without type 2 diabetes (T2DM)] from a phase 1, 4-week multiple dose study received tirzepatide, dulaglutide or placebo. GE was assessed by acetaminophen absorption. In mice, tirzepatide delayed GE to a similar degree to that achieved with semaglutide; however, these acute inhibitory effects were abolished after 2 weeks of treatment. GIP analogue alone had no effect on GE or on GLP-1's effect on GE. In participants with and without T2DM, once-weekly tirzepatide (≥5 and ≥4.5 mg, respectively) delayed GE after a single dose. This effect diminished after multiple doses of tirzepatide or dulaglutide in healthy participants. In participants with T2DM treated with an escalation schedule of tirzepatide 5/5/10/10 or 5/5/10/15 mg, a residual GE delay was still observed after multiple doses. These data suggest that tirzepatide's activity on GE is comparable to that of selective GLP-1RAs.


Assuntos
Diabetes Mellitus Tipo 2 , Receptor do Peptídeo Semelhante ao Glucagon 1 , Animais , Glicemia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Esvaziamento Gástrico , Polipeptídeo Inibidor Gástrico , Peptídeo 1 Semelhante ao Glucagon , Glucose , Camundongos
5.
CPT Pharmacometrics Syst Pharmacol ; 8(9): 664-675, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31250974

RESUMO

The drug-drug interaction profile of atorvastatin confirms that disposition is determined by cytochrome P450 (CYP) 3A4 and organic anion transporting polypeptides (OATPs). Drugs that affect gastric emptying, including dulaglutide, also affect atorvastatin pharmacokinetics (PK). Atorvastatin is a carboxylic acid that exists in equilibrium with a lactone form in vivo. The purpose of this work was to assess gastric acid-mediated lactone equilibration of atorvastatin and incorporate this into a physiologically-based PK (PBPK) model to describe atorvastatin acid, lactone, and their major metabolites. In vitro acid-to-lactone conversion was assessed in simulated gastric fluid and included in the model. The PBPK model was verified with in vivo data including CYP3A4 and OATP inhibition studies. Altering the gastric acid-lactone equilibrium reproduced the change in atorvastatin PK observed with dulaglutide. The model emphasizes the need to include gastric acid-lactone conversion and all major atorvastatin-related species for the prediction of atorvastatin PK.


Assuntos
Atorvastatina/farmacocinética , Gastroparesia/complicações , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Lactonas/química , Proteínas Recombinantes de Fusão/farmacocinética , Atorvastatina/administração & dosagem , Células Cultivadas , Citocromo P-450 CYP3A , Relação Dose-Resposta a Droga , Interações Medicamentosas , Ácido Gástrico/metabolismo , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Peptídeos Semelhantes ao Glucagon/farmacocinética , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Fragmentos Fc das Imunoglobulinas/administração & dosagem , Modelos Biológicos , Transportadores de Ânions Orgânicos , Proteínas Recombinantes de Fusão/administração & dosagem
6.
Mol Metab ; 18: 3-14, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30473097

RESUMO

OBJECTIVE: A novel dual GIP and GLP-1 receptor agonist, LY3298176, was developed to determine whether the metabolic action of GIP adds to the established clinical benefits of selective GLP-1 receptor agonists in type 2 diabetes mellitus (T2DM). METHODS: LY3298176 is a fatty acid modified peptide with dual GIP and GLP-1 receptor agonist activity designed for once-weekly subcutaneous administration. LY3298176 was characterised in vitro, using signaling and functional assays in cell lines expressing recombinant or endogenous incretin receptors, and in vivo using body weight, food intake, insulin secretion and glycemic profiles in mice. A Phase 1, randomised, placebo-controlled, double-blind study was comprised of three parts: a single-ascending dose (SAD; doses 0.25-8 mg) and 4-week multiple-ascending dose (MAD; doses 0.5-10 mg) studies in healthy subjects (HS), followed by a 4-week multiple-dose Phase 1 b proof-of-concept (POC; doses 0.5-15 mg) in patients with T2DM (ClinicalTrials.gov no. NCT02759107). Doses higher than 5 mg were attained by titration, dulaglutide (DU) was used as a positive control. The primary objective was to investigate safety and tolerability of LY3298176. RESULTS: LY3298176 activated both GIP and GLP-1 receptor signaling in vitro and showed glucose-dependent insulin secretion and improved glucose tolerance by acting on both GIP and GLP-1 receptors in mice. With chronic administration to mice, LY3298176 potently decreased body weight and food intake; these effects were significantly greater than the effects of a GLP-1 receptor agonist. A total of 142 human subjects received at least 1 dose of LY3298176, dulaglutide, or placebo. The PK profile of LY3298176 was investigated over a wide dose range (0.25-15 mg) and supports once-weekly administration. In the Phase 1 b trial of diabetic subjects, LY3298176 doses of 10 mg and 15 mg significantly reduced fasting serum glucose compared to placebo (least square mean [LSM] difference [95% CI]: -49.12 mg/dL [-78.14, -20.12] and -43.15 mg/dL [-73.06, -13.21], respectively). Reductions in body weight were significantly greater with the LY3298176 1.5 mg, 4.5 mg and 10 mg doses versus placebo in MAD HS (LSM difference [95% CI]: -1.75 kg [-3.38, -0.12], -5.09 kg [-6.72, -3.46] and -4.61 kg [-6.21, -3.01], respectively) and doses of 10 mg and 15 mg had a relevant effect in T2DM patients (LSM difference [95% CI]: -2.62 kg [-3.79, -1.45] and -2.07 kg [-3.25, -0.88], respectively. The most frequent side effects reported with LY3298176 were gastrointestinal (vomiting, nausea, decreased appetite, diarrhoea, and abdominal distension) in both HS and patients with T2DM; all were dose-dependent and considered mild to moderate in severity. CONCLUSIONS: Based on these results, the pharmacology of LY3298176 translates from preclinical to clinical studies. LY3298176 has the potential to deliver clinically meaningful improvement in glycaemic control and body weight. The data warrant further clinical evaluation of LY3298176 for the treatment of T2DM and potentially obesity.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Polipeptídeo Inibidor Gástrico/uso terapêutico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Hipoglicemiantes/uso terapêutico , Incretinas/uso terapêutico , Receptores dos Hormônios Gastrointestinais/agonistas , Adulto , Animais , Apetite/efeitos dos fármacos , Glicemia/metabolismo , Peso Corporal , Diarreia/etiologia , Feminino , Polipeptídeo Inibidor Gástrico/efeitos adversos , Polipeptídeo Inibidor Gástrico/farmacologia , Humanos , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/farmacologia , Incretinas/efeitos adversos , Incretinas/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Vômito/etiologia
7.
Clin Pharmacokinet ; 56(11): 1415-1427, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28357715

RESUMO

BACKGROUND: Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) for the treatment of type 2 diabetes mellitus are known to delay gastric emptying (GE). The potential effect of the GLP-1 RA dulaglutide on the pharmacokinetics (PK) of four orally administered drugs and on the pharmacodynamic (PD) effect of warfarin was investigated. METHODS: In four separate clinical pharmacology studies, digoxin, warfarin, atorvastatin and Ortho-Cyclen® were orally administered to healthy subjects with and without a subcutaneous dose of dulaglutide 1.5 mg. The effect of dulaglutide coadministration was assessed based on the PK parameters of key analytes. For warfarin PD, the effect of dulaglutide on the international normalized ratio (INR) was evaluated. RESULTS: Areas under the concentration-time curves (AUCs) with and without dulaglutide were similar for all analytes except atorvastatin, where it was reduced by 21%. Maximum concentrations (C max) were generally lower following coadministration with dulaglutide, with statistically significant reductions (90% confidence intervals of geometric least squares means ratios outside 0.80-1.25) for all analytes except R-warfarin. For all analytes, there was a general trend for the time to C max (t max) to increase following coadministration with dulaglutide. For warfarin, dulaglutide coadministration had no statistically significant effect on the maximum INR (INRmax); however, a 2% increase in area under the INR curve (AUCINR) was observed. CONCLUSIONS: Dulaglutide did not affect the absorption of the tested medications to a clinically relevant degree. Based on the PK and PD evaluations, no dose adjustments for digoxin, warfarin, atorvastatin and Ortho-Cyclen® are recommended when coadministered with dulaglutide. CLINICAL TRIAL REGISTRATION NUMBERS: NCT01458210, NCT01436201, NCT01432938, and NCT01250834.


Assuntos
Atorvastatina/farmacocinética , Anticoncepcionais Orais/administração & dosagem , Anticoncepcionais Orais/farmacocinética , Digoxina/farmacocinética , Interações Medicamentosas , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Fragmentos Fc das Imunoglobulinas/administração & dosagem , Fragmentos Fc das Imunoglobulinas/farmacologia , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/farmacologia , Administração Oral , Adolescente , Adulto , Idoso , Atorvastatina/administração & dosagem , Atorvastatina/sangue , Anticoncepcionais Orais/sangue , Digoxina/administração & dosagem , Digoxina/sangue , Feminino , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Peptídeos Semelhantes ao Glucagon/farmacologia , Voluntários Saudáveis , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacologia , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Varfarina/administração & dosagem , Varfarina/sangue , Varfarina/farmacocinética , Adulto Jovem
8.
Diabetes Obes Metab ; 19(4): 517-523, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27976833

RESUMO

AIMS: To evaluate the effects of dulaglutide 1.5 mg on first- and second-phase insulin secretion in response to an intravenous (i.v.) glucose bolus challenge, in subjects with type 2 diabetes mellitus (T2DM; primary objective) and in healthy subjects. MATERIALS AND METHODS: In this randomized, double-blind, placebo-controlled, 2-period crossover study, subjects received a single subcutaneous injection of dulaglutide 1.5 mg or placebo on day 1 of each period. On day 3, subjects underwent a 6-hour insulin infusion, followed by an i.v. glucose bolus and a glucagon challenge during hyperglycaemia. Areas under the concentration-time curve and maximum concentrations for first- (AUC0-10 and Cmax0-10 ) and second-phase secretion (AUC10-180 and Cmax10-180 ) were calculated for insulin and C-peptide. The glucose disappearance constant (Kg ) and homeostasis model assessment of ß-cell function (HOMA-ß) were assessed. RESULTS: In 20 subjects with T2DM, dulaglutide increased mean insulin AUC0-10 by 7.92-fold and Cmax0-10 by 5.40-fold vs placebo, and mean AUC10-180 and Cmax10-180 by 2.44- and 3.78- fold, respectively. In 10 healthy subjects, dulaglutide increased the mean insulin AUC0-10 by 3.09-fold and Cmax0-10 by 2.96-fold vs placebo, and mean AUC10-180 and Cmax10-180 by 2.04- and 4.15-fold, respectively. The corresponding C-peptide values also increased. Mean Kg and HOMA-ß were higher after dulaglutide compared with placebo. CONCLUSIONS: In subjects with T2DM, a single dulaglutide 1.5-mg dose restored the first-phase insulin secretion in response to an i.v. glucose bolus, increased the second-phase insulin response and enhanced ß-cell function.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Glucose/administração & dosagem , Hipoglicemiantes/administração & dosagem , Fragmentos Fc das Imunoglobulinas/administração & dosagem , Insulina/sangue , Proteínas Recombinantes de Fusão/administração & dosagem , Adulto , Área Sob a Curva , Glicemia/efeitos dos fármacos , Peptídeo C/sangue , Estudos Cross-Over , Diabetes Mellitus Tipo 2/fisiopatologia , Método Duplo-Cego , Esquema de Medicação , Feminino , Glucagon , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Humanos , Hiperglicemia/tratamento farmacológico , Infusões Intravenosas , Injeções Subcutâneas , Células Secretoras de Insulina/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
9.
Clin Pharmacokinet ; 55(5): 625-34, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26507721

RESUMO

BACKGROUND AND OBJECTIVE: Dulaglutide is a long-acting glucagon-like peptide-1 receptor agonist administered as once-weekly subcutaneous injections for the treatment of type 2 diabetes (T2D). The clinical pharmacokinetics of dulaglutide were characterized in patients with T2D and healthy subjects. METHODS: The pharmacokinetics of dulaglutide were assessed throughout clinical development, including conventional pharmacokinetic analysis in clinical pharmacology studies and population pharmacokinetic analyses of data from combined phase 2 and phase 3 studies in patients with T2D. The effects of potential covariates on dulaglutide population pharmacokinetics were evaluated using nonlinear mixed-effects models. RESULTS: Dulaglutide gradually reached the maximum concentration in 48 h and had a terminal elimination half-life of 5 days. Steady state was achieved between the second and fourth doses. The accumulation ratio was 1.56 for the 1.5 mg dose. Intra-individual variability estimates for the area under the plasma concentration-time curve and the maximum concentration were both <17% [coefficient of variation (CV)]. There was no difference in pharmacokinetics between injection sites (arm, thigh or abdomen). Dulaglutide pharmacokinetics were well described by a two-compartment model with first-order absorption and elimination. The population clearance was estimated at 0.126 L/h [inter-individual variability (CV) 33.8%]. Age, body weight, sex, race and ethnicity did not influence dulaglutide pharmacokinetics to any clinically relevant degree. CONCLUSION: The pharmacokinetics of dulaglutide support once-weekly administration in patients with T2D. The pharmacokinetic findings suggest that dose adjustment is not necessary on the basis of body weight, sex, age, race or ethnicity or site of injection.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Hipoglicemiantes/farmacocinética , Proteínas Recombinantes de Fusão/farmacocinética , Adulto , Idoso , Idoso de 80 Anos ou mais , Vias de Administração de Medicamentos , Feminino , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Peptídeos Semelhantes ao Glucagon/sangue , Peptídeos Semelhantes ao Glucagon/farmacocinética , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/sangue , Fragmentos Fc das Imunoglobulinas/administração & dosagem , Fragmentos Fc das Imunoglobulinas/sangue , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/sangue , Adulto Jovem
10.
J Clin Densitom ; 18(4): 506-11, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25824332

RESUMO

The purpose of this analysis was to assess the association of osteoporosis-related vertebral fracture burden and pulmonary function. This study also examined the relationship between vertebral fracture burden and height loss, estimated by arm span - height. This was a single-site and single-visit study. Patients had a history of at least 1 moderate or severe vertebral fracture. Vertebral fracture burden was quantified using the spinal deformity index (SDI). Pulmonary function during inspiration was determined by spirometry. Forty-one women aged 70-91 completed the study. Vertebral fracture burden negatively correlated with forced inspiratory vital capacity and inspiratory time. For each unit increase in SDI, forced inspiratory vital capacity decreased by 1.62%, and inspiratory time decreased by 2.39%. There was no correlation between SDI and measures of inspiratory flow. For each unit increase in SDI, height decreased by about 0.5 cm. Vertebral fractures were associated with decreased lung volume and height loss.


Assuntos
Estatura , Pulmão/fisiopatologia , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/fisiopatologia , Traumatismos da Coluna Vertebral/etiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Traumatismos da Coluna Vertebral/fisiopatologia , Espirometria
11.
Br J Clin Pharmacol ; 75(2): 538-49, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22803597

RESUMO

AIM: The effects of atomoxetine (20 and 60 mg twice daily), 400 mg moxifloxacin and placebo on QT(c) in 131 healthy CYP2D6 poor metabolizer males were compared. METHODS: Atomoxetine doses were selected to result in plasma concentrations that approximated expected plasma concentrations at both the maximum recommended dose and at a supratherapeutic dose in CYP2D6 extensive metabolizers. Ten second electrocardiograms were obtained for time-matched baseline on days -2 and -1, three time points after dosing on day 1 for moxifloxacin and five time points on day 7 for atomoxetine and placebo. Maximum mean placebo-subtracted change from baseline model-corrected QT (QT(c)M) on day 7 was the primary endpoint. RESULTS: QT(c)M differences for atomoxetine 20 and 60 mg twice daily were 0.5 ms (upper bound of the one-sided 95% confidence interval 2.2 ms) and 4.2 ms (upper bound of the one-sided 95% confidence interval 6.0 ms), respectively. As plasma concentration of atomoxetine increased, a statistically significant increase in QT(c) was observed. The moxifloxacin difference from placebo met the a priori definition of non-inferiority. Maximum mean placebo-subtracted change from baseline QT(c)M for moxifloxacin was 4.8 ms and this difference was statistically significant. Moxifloxacin plasma concentrations were below the concentrations expected from the literature. However, the slope of the plasma concentration-QT(c) change observed was consistent with the literature. CONCLUSION: Atomoxetine was not associated with a clinically significant change in QT(c). However, a statistically significant increase in QT(c) was associated with increasing plasma concentrations.


Assuntos
Inibidores da Captação Adrenérgica/farmacologia , Compostos Aza/farmacologia , Citocromo P-450 CYP2D6/metabolismo , Eletrocardiografia/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Propilaminas/farmacologia , Quinolinas/farmacologia , Inibidores da Topoisomerase II/farmacologia , Inibidores da Captação Adrenérgica/farmacocinética , Adulto , Cloridrato de Atomoxetina , Compostos Aza/farmacocinética , Estudos Cross-Over , Relação Dose-Resposta a Droga , Fluoroquinolonas , Humanos , Masculino , Moxifloxacina , Propilaminas/farmacocinética , Quinolinas/farmacocinética , Inibidores da Topoisomerase II/farmacocinética , Adulto Jovem
12.
Pacing Clin Electrophysiol ; 34(9): 1116-27, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21535038

RESUMO

BACKGROUND: Many thorough QT (TQT) studies use a baseline day and double delta analysis to account for potential diurnal variation in QTc. However, little is known about systematic changes in the QTc across contiguous days when normal volunteers are brought into a controlled inpatient environment. METHODS: Two separate crossover TQT studies included 2 days of no treatment lead-in days with ECG collection preceding periods of drug treatment . In the first study, there were two pairs of such contiguous days with 10 replicate electrocardiograms (ECGs) collected at six time points, and in the second study, there were four pairs of contiguous days with nine replicate ECGs collected at five time points. These lead-in day pairs provided the opportunity to evaluate any systematic changes across contiguous first and second days of an inpatient environment. Within-patient consistency of change across pairs of days as well as within day, diurnal variation could also be evaluated. RESULTS: Modest (4.2 ms [range 1.9-6.5 ms]) but consistent decreases (significant [P < 0.05] for all 32 comparisons) were observed (probability: ≤5.4 × 10(-16)). Although group behavior with respect to QTc was consistent, individual subjects demonstrated substantial variability across pairs of days. Evidence of diurnal variation was weak and inconsistent. Magnitude of any diurnal variation was less than magnitude of change across days. CONCLUSIONS: Subjects show a systematic decrease in QTc from first day to second day of inpatient status and do not demonstrate a significant diurnal pattern. The magnitude of this systematic change is sufficient to influence QTc study interpretation.


Assuntos
Ritmo Circadiano/fisiologia , Eletrocardiografia/métodos , Frequência Cardíaca/fisiologia , Coração/fisiologia , Adolescente , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
13.
Clin Pharmacokinet ; 47(2): 103-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18193916

RESUMO

OBJECTIVE: The purpose of this study was to characterize duloxetine pharmacokinetics in the breast milk and plasma of lactating women and to estimate the duloxetine dose that an infant might consume if breastfed. METHODS: This open-label study included six healthy women aged 22-35 years who stopped nursing during and after the study. Duloxetine 40 mg was given orally every 12 hours for 3.5 days; seven plasma and milk samples over 12 hours were obtained after the seventh dose. Plasma and milk samples were analysed using validated liquid chromatography-tandem mass spectrometry methods. Safety measures included vital signs, ECGs, laboratory tests, adverse event monitoring and depression rating scales. RESULTS: The mean steady-state milk-to-plasma duloxetine exposure ratio was 0.25 (90% CI 0.18, 0.35). The amount of duloxetine in the breast milk was 7 microg/day (range 4-15 microg/day). The estimated infant dose was 2 microg/kg/day (range 0.6-3 microg/kg/day), which is 0.14% of the maternal dose. Dizziness, nausea and fatigue were commonly reported adverse events. No clinically important changes in safety measures occurred. CONCLUSION: Duloxetine is detected in breast milk, and steady-state concentrations in breast milk are about one-fourth of those in maternal plasma. As the safety of duloxetine in infants is unknown, prescribers should carefully assess, on an individual basis, the potential risks of duloxetine exposure to infants and the benefits of nursing an infant when the mother is on duloxetine therapy.


Assuntos
Leite Humano/metabolismo , Período Pós-Parto/metabolismo , Tiofenos/farmacocinética , Administração Oral , Adulto , Algoritmos , Área Sob a Curva , Pressão Sanguínea/efeitos dos fármacos , Índice de Massa Corporal , Cápsulas , Cromatografia Líquida , Tontura/induzido quimicamente , Relação Dose-Resposta a Droga , Cloridrato de Duloxetina , Fadiga/induzido quimicamente , Feminino , Cefaleia/induzido quimicamente , Frequência Cardíaca/efeitos dos fármacos , Humanos , Lactação/sangue , Lactação/metabolismo , Náusea/induzido quimicamente , Período Pós-Parto/sangue , Inibidores Seletivos de Recaptação de Serotonina/administração & dosagem , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Inibidores Seletivos de Recaptação de Serotonina/farmacocinética , Espectrometria de Massas em Tandem , Tiofenos/sangue , Tiofenos/metabolismo
14.
Circulation ; 109(25): 3202-7, 2004 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-15184278

RESUMO

BACKGROUND: To assess the sensitivity of biochemical, physiological, and pharmacological markers of peripheral norepinephrine (NE) transporter (NET) function, we chronically antagonized NET by a range of doses of duloxetine [(+)-N-methyl-3-(1-naphthalenyloxy)-2 thiophenepropanamine], which blocks the NE reuptake process. METHODS AND RESULTS: Duloxetine was administered in a randomized, placebo-controlled study in 15 healthy volunteers. Plasma from duloxetine-treated subjects (ex vivo effect) dose-dependently decreased radioligand binding to human NET (maximum inhibition was 60%) (P=0.02). The dose of intravenous tyramine required to raise systolic blood pressure by 30 mm Hg (PD30) increased dose-dependently with duloxetine and was significant at the end of the 120-mg/d dosage (P<0.001). The plasma dihydoxyphenylglycol to NE (DHPG/NE) ratio was reduced significantly at 2 weeks of treatment with 80 mg/d duloxetine (11.3 at baseline, 3.4 at 240 mg/d, P<0.001). Plasma NE was significantly increased starting at 120 mg/d duloxetine. Urine results (corrected for 24-hour creatinine excretion) showed a dose-dependent change from the baseline urinary excretion for NE, DHPG, and the DHPG/NE ratio. The most sensitive measure, the DHPG/NE ratio, was significant at the 80-mg dose. Urinary NE excretion was significantly raised after 2 weeks of treatment with 80 mg/d duloxetine (P<0.001), the lowest dose used in the study. CONCLUSIONS: These findings suggest that the degree of NET blockade can be assessed with the plasma or urine DHPG/NE ratio and the pressor effect of tyramine. Also, the DHPG/NE ratio is more sensitive at the lower end of NET inhibition, whereas tyramine exhibits a linear relation, with NET inhibition commencing at a higher dose.


Assuntos
Inibidores da Captação Adrenérgica/farmacologia , Metoxi-Hidroxifenilglicol/análogos & derivados , Simportadores/antagonistas & inibidores , Tiofenos/farmacologia , Adolescente , Inibidores da Captação Adrenérgica/administração & dosagem , Adulto , Relação Dose-Resposta a Droga , Cloridrato de Duloxetina , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Metoxi-Hidroxifenilglicol/urina , Norepinefrina/sangue , Norepinefrina/urina , Proteínas da Membrana Plasmática de Transporte de Norepinefrina , Postura , Ensaio Radioligante , Sensibilidade e Especificidade , Sístole/efeitos dos fármacos , Tiofenos/administração & dosagem , Tiramina/administração & dosagem , Tiramina/farmacologia
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