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1.
Int J Clin Pharmacol Ther ; 53(9): 772-82, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26227099

RESUMEN

OBJECTIVE: Corifollitropin alfa (Elonva®) is the first hybrid follicle-stimulating hormone molecule with demonstrated sustained follicle-stimulating activity after a single subcutaneous injection. This trial evaluated if corifollitropin alfa is associated with QT/QTc prolongation and/ or proarrhythmic potential as compared to placebo in healthy post-menopausal women. MATERIALS: Participants were healthy, postmenopausal women. Study treatments were corifollitropin alfa 150 µg, corifollitropin alfa 240 µg, and moxifloxacin 400 mg with placebo. METHODS: This randomized, double blind, double-dummy, 4-period crossover trial compared single doses of corifollitropin alfa 150 µg (therapeutic dose), corifollitropin alfa 240 µg (supratherapeutic dose), and moxifloxacin 400 mg (positive control) with placebo. Corifollitropin alfa was administered on day 1 and moxifloxacin on day 2. RESULTS: The largest time-matched mean QTcF difference versus placebo for the therapeutic dose of corifollitropin alfa was 1.4 ms (upper limit of 1-sided 95% confidence interval (UL 95% CI) = 3.4 ms), and for the supratherapeutic dose was 1.2 ms (UL 95% CI = 3.6 ms). CONCLUSIONS: For both the therapeutic and the supratherapeutic dose of corifollitropin alfa and at all time points, the UL 95% CI for the time matched QTcF differences compared with placebo was below 10 ms, the threshold of relevance defined by the ICH E14 guideline. Single therapeutic and supratherapeutic doses of corifollitropin alfa are not associated with clinically relevant QT/QTc-interval prolongation in healthy post-menopausal women.


Asunto(s)
Electrocardiografía/efectos de los fármacos , Hormona Folículo Estimulante Humana/farmacología , Adulto , Anciano , Estudios Cruzados , Método Doble Ciego , Femenino , Fluoroquinolonas/administración & dosificación , Hormona Folículo Estimulante Humana/efectos adversos , Hormona Folículo Estimulante Humana/farmacocinética , Humanos , Persona de Mediana Edad , Moxifloxacino , Posmenopausia
2.
Int J Clin Pharmacol Ther ; 50(8): 595-604, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22735462

RESUMEN

OBJECTIVE: Sugammadex is a novel γ-cyclodextrin and the first selective relaxant binding agent to be developed for the reversal of rocuronium and vecuroniuminduced neuromuscular blockade. According to International Conference on Harmonization (ICH) E14, a thorough QT/QTc study is required for most new compounds to assess the potential to cause QT prolongation, because a delay in cardiac repolarization may create an electrophysiological environment that favors the development of cardiac arrhythmias, most notably Torsade de Pointes. Therefore a thorough QTc study was conducted to evaluate the effect of sugammadex on the individually corrected QTc interval (QTcI). METHODS: Following two baseline electrocardiogram (ECG) days (Day -2 and Day -1), in this randomized, double-blind, cross-over study, healthy volunteers received a sequence of four treatments comprising single intravenous doses of placebo, moxifloxacin 400 mg (positive control, open label), sugammadex 4 mg/kg and sugammadex 32 mg/kg. ECGs were recorded in triplicate at 12 time points up to ~ 24 h after study drug administration, and the QT intervals were evaluated manually under blinded conditions. The pre-specified primary endpoint was the largest time-matched mean QTcI difference compared with placebo across all time points. RESULTS: A total of 62 subjects received treatment, of which 58 completed the study. After intravenous moxifloxacin, QTcI prolongations compared with placebo exceeded the ICH E14 safety margin of 10 msec and the one-sided 95% lower confidence limit exceeded 5 msec, confirming assay sensitivity. For both sugammadex doses, the one-sided 95% upper confidence limits for the largest time-matched mean QTcI differences compared with placebo were ≤ 5.3 msec at each timepoint and thus considerably below the 10 msec safety margin. Unexpectedly, the two full-day baseline ECGs indicated systematically prolonged QTc values when comparing the first baseline with the second baseline day, reaching a maximum mean difference of 3.8 msec. CONCLUSION: Single therapeutic (4 mg/kg) and supra-therapeutic (32 mg/kg) intravenous doses of sugammadex are not associated with clinically important QTc prolongation.


Asunto(s)
Antiinfecciosos/efectos adversos , Compuestos Aza/efectos adversos , Síndrome de QT Prolongado/inducido químicamente , Fármacos Neuromusculares/efectos adversos , Quinolinas/efectos adversos , gamma-Ciclodextrinas/efectos adversos , Adolescente , Adulto , Anciano , Antiinfecciosos/administración & dosificación , Compuestos Aza/administración & dosificación , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Electrocardiografía/efectos de los fármacos , Femenino , Fluoroquinolonas , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Moxifloxacino , Fármacos Neuromusculares/administración & dosificación , Quinolinas/administración & dosificación , Sugammadex , gamma-Ciclodextrinas/administración & dosificación
3.
Clin Drug Investig ; 30(9): 599-611, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20568829

RESUMEN

BACKGROUND: Sugammadex reverses the effects of rocuronium- and vecuronium-induced neuromuscular blockade, which are achieved by encapsulation. It is known that some non-antiarrhythmic drugs have the potential to delay cardiac repolarization and it is therefore recommended that the effects of all new drugs on the QT interval are assessed. OBJECTIVE: This thorough corrected QT (QTc) study evaluated the effect of sugammadex alone and in combination with rocuronium or vecuronium on the individually corrected QTc interval (QTcI). METHODS: This was a randomized, double-blind, six-period crossover, placebo-controlled study, with an open-label active-controlled component (moxifloxacin). The study was designed according to International Conference on Harmonization (ICH) E14 guidelines. The study was conducted in a clinical research unit from November 2006 to April 2007. Healthy male and female subjects (n = 84) were enrolled in the study. Subjects were randomized to six treatment sequences comprising single intravenous doses of placebo, moxifloxacin 400 mg (positive control), sugammadex 4 mg/kg, sugammadex 32 mg/kg, sugammadex 32 mg/kg with rocuronium 1.2 mg/kg and sugammadex 32 mg/kg with vecuronium 0.1 mg/kg. Triplicate ECGs were recorded at 13 timepoints up to 23.5 hours after study drug administration and QT intervals were evaluated manually under blinded conditions. The primary outcome was the largest time-matched mean difference in QTcI change from baseline compared with placebo across the 13 timepoints up to 23.5 hours after study drug administration. Blood samples were also collected for pharmacokinetic analysis. RESULTS: Of the 84 randomized healthy subjects, 80 completed the study. After moxifloxacin, QTcI prolongations were observed compared with placebo; the lower limit of the one-sided 95% confidence interval (CI) for the largest time-matched mean difference in QTcI change compared with placebo was 20.8 msec (90% CI 18.5, 23.1), thus exceeding the ICH E14 safety margin of 5 msec and demonstrating assay sensitivity. In contrast, the largest time-matched mean difference in QTcI (msec) from placebo with sugammadex treatments ranged from 2.1 (sugammadex 4 mg/kg alone) to 4.3 (sugammadex 32 mg/kg with vecuronium 0.1 mg/kg). For the largest time-matched mean difference in QTcI change compared with placebo the corresponding upper limit of the one-sided 95% CI was well below the 10 msec margin for both sugammadex doses. Telemetry results revealed that one subject experienced a non-sustained ventricular tachycardia 4 hours after sugammadex 32 mg/kg, which was self-terminating after 20 beats and considered unlikely to be drug related. Pharmacokinetic-QTc analysis showed a statistically significant (p < 0.01) relationship between sugammadex plasma concentration and QTcI; however, at mean maximum plasma concentrations of the therapeutic and supra-therapeutic sugammadex dose, the predicted one-sided upper 95% CI for the largest time-matched QTcI difference from placebo was below 10 msec. Rocuronium or vecuronium co-administration did not affect the relationship between sugammadex concentrations and QTc. CONCLUSIONS: Based on the results of this study of healthy subjects, it can be concluded that sugammadex alone or in combination with rocuronium or vecuronium is not associated with QTc prolongation.


Asunto(s)
Androstanoles/administración & dosificación , Arritmias Cardíacas/inducido químicamente , Compuestos Aza/administración & dosificación , Frecuencia Cardíaca/efectos de los fármacos , Fármacos Neuromusculares no Despolarizantes/administración & dosificación , Quinolinas/administración & dosificación , Bromuro de Vecuronio/administración & dosificación , gamma-Ciclodextrinas/administración & dosificación , Adolescente , Adulto , Androstanoles/efectos adversos , Arritmias Cardíacas/fisiopatología , Compuestos Aza/efectos adversos , Estudios Cruzados , Método Doble Ciego , Electrocardiografía , Femenino , Fluoroquinolonas , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Modelos Biológicos , Moxifloxacino , Fármacos Neuromusculares no Despolarizantes/efectos adversos , Quinolinas/efectos adversos , Medición de Riesgo , Factores de Riesgo , Rocuronio , Sugammadex , Factores de Tiempo , Bromuro de Vecuronio/efectos adversos , Adulto Joven , gamma-Ciclodextrinas/efectos adversos , gamma-Ciclodextrinas/farmacocinética
4.
Breast Cancer Res ; 9(4): R52, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17692126

RESUMEN

INTRODUCTION: In contrast to nonsteroidal aromatase inhibitors, the steroidal aromatase inactivator exemestane does not have detrimental effects on bone in animal models. This study was designed to compare the effects of exemestane with the nonsteroidal aromatase inhibitors anastrozole and letrozole on serum and urine levels of biomarkers of bone turnover in healthy postmenopausal women. METHODS: Changes in the concentrations of bone-turnover markers, estrogens, and lipids were assessed after daily administration of exemestane (25 mg), letrozole (2.5 mg), anastrozole (1 mg), or placebo for 24 weeks in healthy postmenopausal women. The primary end point was the percentage change from baseline in bone-turnover-marker levels at week 24. The baseline-adjusted area under the curve (AUC) for weeks 0-12 and 0-24 was calculated to evaluate changes in bone turnover over time, rather than at discrete time points. RESULTS: Seventy-four (88%) of 84 randomized subjects were evaluable for bone-marker assays. Reductions in plasma estrogen levels and increases in bone-resorption markers were comparable for each aromatase inhibitor. Uniquely, exemestane consistently increased the percentage change from baseline in the level of serum procollagen type I N-terminal propeptide (PINP), a marker of bone formation, at week 24. In the active-treatment groups, the baseline-adjusted AUC at weeks 0-12 and 0-24 for PINP was significantly greater for exemestane than the other aromatase inhibitors. CONCLUSION: Exemestane increased serum levels of the bone-formation marker PINP after 24 weeks, suggesting a specific bone-formation effect related to its androgenic structure. Potential effects on cortical bone and reduced fracture risk must be verified in a comparative clinical trial.


Asunto(s)
Inhibidores de la Aromatasa/administración & dosificación , Densidad Ósea/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Lípidos/sangre , Anciano , Anastrozol , Androstadienos/administración & dosificación , Antineoplásicos Hormonales/administración & dosificación , Biomarcadores/sangre , Remodelación Ósea , Resorción Ósea , Neoplasias de la Mama/sangre , Neoplasias de la Mama/patología , Estrógenos/sangre , Femenino , Humanos , Letrozol , Menopausia , Persona de Mediana Edad , Nitrilos/administración & dosificación , Fragmentos de Péptidos/sangre , Placebos , Procolágeno/sangre , Método Simple Ciego , Tamoxifeno/uso terapéutico , Triazoles/administración & dosificación
5.
Clin Pharmacol Ther ; 80(2): 126-35, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16890574

RESUMEN

OBJECTIVES: Cytochrome P450 (CYP) 2C19 and CYP3A4 are the major enzymes responsible for voriconazole elimination. Because the activity of CYP2C19 is under genetic control, the extent of inhibition with a CYP3A4 inhibitor was expected to be modulated by the CYP2C19 metabolizer status. This study thus assessed the effect of the potent CYP3A4 inhibitor ritonavir after short-term administration on voriconazole pharmacokinetics in extensive metabolizers (EMs) and poor metabolizers (PMs) of CYP2C19. METHODS: In a randomized, placebo-controlled crossover study, 20 healthy participants who were stratified according to CYP2C19 genotype received oral ritonavir (300 mg twice daily) or placebo for 2 days. Together with the first ritonavir or placebo dose, a single oral dose of 400 mg voriconazole was administered. Voriconazole was determined in plasma and urine by liquid chromatography-mass spectrometry, and pharmacokinetic parameters were estimated by noncompartmental analysis. RESULTS: When given alone, the apparent oral clearance of voriconazole after single oral dosing was 26%+/-16% (P > .05) lower in CYP2C19*1/*2 individuals and 66%+/-14% (P < .01) lower in CYP2C19 PMs. The addition of ritonavir caused a major reduction in voriconazole apparent oral clearance (354+/-173 mL/min versus 202+/-139 mL/min, P = .0001). This reduction occurred in all CYP2C19 genotypes (463+/-168 mL/min versus 305+/-112 mL/min [P = .023] for *1/*1, 343+/-127 mL/min versus 190+/-93 mL/min [P = .008] for *1/*2, and 158+/-54 mL/min versus 22+/-11 mL/min for *2/*2) and is probably caused by inhibition of CYP3A4-mediated voriconazole metabolism. CONCLUSIONS: Coadministration of a potent CYP3A4 inhibitor leads to a higher and prolonged exposure with voriconazole that might increase the risk of the development of adverse drug reactions on a short-term basis, particularly in CYP2C19 PM patients.


Asunto(s)
Fármacos Anti-VIH/efectos adversos , Antifúngicos/farmacocinética , Hidrocarburo de Aril Hidroxilasas/genética , Hidrocarburo de Aril Hidroxilasas/metabolismo , Inhibidores Enzimáticos del Citocromo P-450 , Inhibidores Enzimáticos , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Pirimidinas/farmacocinética , Ritonavir/efectos adversos , Triazoles/farmacocinética , Adulto , Alelos , Antifúngicos/efectos adversos , Área Bajo la Curva , Estudios Cruzados , Citocromo P-450 CYP2C19 , Citocromo P-450 CYP3A , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Genotipo , Humanos , Masculino , Pirimidinas/efectos adversos , Triazoles/efectos adversos , Voriconazol
6.
Clin Pharmacol Ther ; 77(6): 529-41, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15961984

RESUMEN

BACKGROUND: Levetiracetam is an antiepileptic drug approved for use as adjunctive therapy in adults with partial-onset seizures. We sought to investigate possible changes in the pharmacokinetics of levetiracetam and its metabolite ucb L057 in patients with liver cirrhosis, who may require dose adjustments. METHODS: A single dose of levetiracetam was administered to 5 healthy subjects and to patients with Child-Pugh class A (n = 5), B (n = 6), or C (n = 5) alcohol-induced cirrhosis. The pharmacokinetics of levetiracetam and ucb L057 was measured and correlated with biochemical liver function parameters, with creatinine clearance, and with kinetics of caffeine, lidocaine, and d -sorbitol as probes for specific liver functions. RESULTS: Dynamic liver function tests revealed a deterioration of liver function. The pharmacokinetics of levetiracetam and its metabolite did not differ between healthy subjects and those with class A or B cirrhosis. However, in patients with class C cirrhosis, levetiracetam total clearance was reduced by 57% (90% confidence interval [CI], 43%-67%; P < .001). The geometric mean ratio of the area under the plasma concentration-time curve for levetiracetam, Child-Pugh class C versus control, was 2.41 (90% CI, 1.80-3.23), and the geometric mean of the half-life ratio was 2.27 (90% CI, 1.74-2.97). This was explained by the deterioration of renal function in patients with severe hepatic disease. CONCLUSIONS: In pharmacokinetic studies of hepatic impairment, including all classes of cirrhosis may be more revealing than including only selected classes of liver failure. No dose adjustment of levetiracetam is necessary in patients with mild to moderate liver impairment; however, patients with severe cirrhosis should initially receive only half of the commonly recommended dose.


Asunto(s)
Anticonvulsivantes/farmacocinética , Cirrosis Hepática Alcohólica/metabolismo , Piracetam/análogos & derivados , Piracetam/farmacocinética , Adulto , Cafeína/farmacocinética , Humanos , Pruebas de Función Renal , Levetiracetam , Lidocaína/farmacocinética , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Sorbitol/farmacocinética
7.
Clin Pharmacol Ther ; 78(1): 25-33, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16003289

RESUMEN

OBJECTIVES: Constituents of St John's wort (SJW) in vivo induce the cytochrome P450 (CYP) isozymes 3A4, 2C9, and 2C19 but in vitro were shown to inhibit them. This study investigates both short- and long-term effects of SJW on the antifungal voriconazole, which is metabolized by these enzymes. METHODS: In a controlled, open-label study, single oral doses of 400 mg voriconazole were administered to 16 healthy men stratified for CYP2C19 genotype before and on day 1 and day 15 of concomitant SJW intake (300 mg LI 160 3 times daily). Plasma and urine concentrations of voriconazole were determined by liquid chromatography with mass-spectrometric detection. RESULTS: During the initial 10 hours of the first day of SJW administration, the area under the voriconazole plasma concentration-time curve was increased by 22% compared with control (15.5 +/- 6.84 h . microg/mL versus 12.7 +/- 4.16 h . microg/mL, P = .02). After 15 days of SJW intake, the area under the plasma concentration-time curve from hour 0 to infinity was reduced by 59% compared with control (9.63 +/- 6.03 h . microg/mL versus 23.5 +/- 15.6 h . microg/mL, P = .0004), with a corresponding increase in oral voriconazole clearance (CL/F) from 390 +/- 192 to 952 +/- 524 mL/min (P = .0004). The baseline CL/F of voriconazole and the absolute increase in CL/F were smaller in carriers of 1 or 2 deficient CYP2C19*2 alleles compared with wild-type individuals (P < .03). CONCLUSIONS: Coadministration of SJW leads to a short-term but clinically irrelevant increase followed by a prolonged extensive reduction in voriconazole exposure. SJW might put CYP2C19 wild-type individuals at highest risk for potential voriconazole treatment failure.


Asunto(s)
Tasa de Depuración Metabólica/efectos de los fármacos , Extractos Vegetales/farmacocinética , Pirimidinas/antagonistas & inhibidores , Pirimidinas/farmacocinética , Triazoles/antagonistas & inhibidores , Triazoles/farmacocinética , Administración Oral , Adulto , Alelos , Área Bajo la Curva , Hidrocarburo de Aril Hidroxilasas/efectos de los fármacos , Hidrocarburo de Aril Hidroxilasas/genética , Hidrocarburo de Aril Hidroxilasas/metabolismo , Cromatografía Liquida/métodos , Citocromo P-450 CYP2C19 , Esquema de Medicación , Sinergismo Farmacológico , Quimioterapia Combinada , Cromatografía de Gases y Espectrometría de Masas/métodos , Genotipo , Semivida , Humanos , Hypericum , Masculino , Tasa de Depuración Metabólica/genética , Oxigenasas de Función Mixta/efectos de los fármacos , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Selección de Paciente , Extractos Vegetales/administración & dosificación , Extractos Vegetales/química , Pirimidinas/administración & dosificación , Factores de Tiempo , Triazoles/administración & dosificación , Voriconazol
8.
Clin Pharmacokinet ; 44(4): 429-38, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15828855

RESUMEN

BACKGROUND: Two pharmacokinetic studies were performed to investigate whether there is any interaction between etonogestrel or ethinylestradiol released from the combined contraceptive vaginal ring NuvaRing and concomitant treatment with orally administered amoxicillin or doxycycline. METHODS: In one study, healthy women were randomised to receive either NuvaRing alone for 21 days or NuvaRing for 21 days plus amoxicillin on days 1-10. After a 7-day ring-free washout period, women were crossed over to the alternate regimen for a further 21-day treatment period. The other study used an identical design except that women received doxycycline instead of amoxicillin. The amoxicillin study measured serum etonogestrel and ethinylestradiol levels and area under the serum concentration-time curve (AUC) values over the initial 12 hours on days 1 (AUC(12)) and 10 (AUC(216-228)) and the whole of days 1-11 (AUC(240)) and 1-22 (AUC(504)). The doxycycline study measured AUC values over the initial 24 hours on days 1 (AUC(24)) and 10 (AUC(216-240)) and the whole of days 1-11 (AUC(240)) and 1-22 (AUC(504)). RESULTS: No differences in etonogestrel or ethinylestradiol serum concentrations were observed between subjects using NuvaRing alone versus those receiving the ring plus either of the antibiotics. Calculation of etonogestrel and ethinylestradiol interaction/control ratios confirmed the absence of pharmacokinetic interactions. CONCLUSION: The results from these studies demonstrate the absence of pharmacokinetic interactions between etonogestrel and ethinylestradiol released from NuvaRing and the oral antibiotics amoxicillin and doxycycline, suggesting that contraceptive efficacy would also be unaffected.


Asunto(s)
Amoxicilina/farmacología , Antibacterianos/farmacología , Anticonceptivos Femeninos/sangre , Desogestrel/sangre , Doxiciclina/farmacología , Etinilestradiol/sangre , Adolescente , Adulto , Área Bajo la Curva , Estudios Cruzados , Preparaciones de Acción Retardada , Desogestrel/administración & dosificación , Sistemas de Liberación de Medicamentos , Etinilestradiol/administración & dosificación , Femenino , Humanos
9.
Clin Drug Investig ; 34(6): 413-20, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24777591

RESUMEN

BACKGROUND AND OBJECTIVE: Nomegestrol acetate (NOMAC)/17ß-estradiol (E2) is a monophasic oral contraceptive that contains a progesterone-derived progestogen (NOMAC), and E2, a bio-identical estrogen. The primary objective of this thorough QT/QTc study was to investigate whether once-daily administration of therapeutic (2.5/1.5 mg) and supratherapeutic (12.5/7.5 mg) doses of NOMAC/E2 were associated with prolongation of the mean Fridericia-corrected QT (QTcF) interval in electrocardiograms at steady-state concentrations of NOMAC/E2 versus placebo. The co-primary objective was to establish assay sensitivity after a single dose of moxifloxacin (positive control). METHODS: This was a randomized, double-blind, parallel-group trial comparing 2.5/1.5 mg of NOMAC/E2 (therapeutic dose), 12.5/7.5 mg of NOMAC/E2 (supratherapeutic dose), placebo, and moxifloxacin 400 mg. Double-blind study medication was administered from day -1 to 14. Healthy women aged 18-50 years were randomized. RESULTS: The largest time-matched mean QTcF difference compared with placebo for the therapeutic dose of NOMAC/E2 was 1.6 ms, with an upper limit (UL) of a one-sided 95% confidence interval (CI) of 5.2 ms, and 3.1 ms with an UL 95% CI of 7.0 ms for the supratherapeutic dose. The UL for the time-matched QTcF differences compared with placebo were below the 10 ms threshold defined in the ICH E14 guideline for all time points, both for the therapeutic and the supratherapeutic dose. For moxifloxacin, assay sensitivity was demonstrated. CONCLUSIONS: This thorough QT/QTc study showed that therapeutic and supratherapeutic doses of NOMAC/E2 were not associated with clinically relevant QTc interval prolongation in healthy women after a 2-week period of dosing.


Asunto(s)
Anticonceptivos Orales Combinados/efectos adversos , Estradiol/efectos adversos , Síndrome de QT Prolongado/inducido químicamente , Megestrol/efectos adversos , Norpregnadienos/efectos adversos , Administración Oral , Adolescente , Adulto , Anticonceptivos Orales Combinados/administración & dosificación , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Electrocardiografía , Estradiol/administración & dosificación , Femenino , Fluoroquinolonas/efectos adversos , Humanos , Megestrol/administración & dosificación , Persona de Mediana Edad , Moxifloxacino , Norpregnadienos/administración & dosificación , Factores de Tiempo , Adulto Joven
10.
J Clin Pharmacol ; 53(11): 1199-204, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23939663

RESUMEN

This study aimed to demonstrate that the dose of a CYP3A substrate (simvastatin) can be adapted individually on the basis of CYP3A activity as assessed by midazolam metabolic clearance. In 18 healthy participants individual CYP3A activity was quantified using midazolam metabolic clearance both alone and during CYP3A inhibition with 40 mg ritonavir. Thereafter, simvastatin acid exposure was determined after a simvastatin standard dose (40 mg) and doses adapted to individual CYP3A activity at baseline and during CYP3A inhibition. Interindividual variability of CYP3A activity and simvastatin acid AUC0-24 was large and both correlated (r(2) = 0.745, P < .001). The adapted simvastatin doses ranged from 25 to 80 mg and their administration reduced simvastatin variability fivefold. Despite the low adapted simvastatin dose of 12 mg during CYP3A inhibition with ritonavir, exposure increased (point estimate of 4.2 [90% CI: 3.15-5.61]) probably caused by additional OATP1B1 inhibition. CYP3A activity-based dose adaptation can be used to reduce interindividual variability in simvastatin exposure.


Asunto(s)
Citocromo P-450 CYP3A/metabolismo , Midazolam/farmacocinética , Simvastatina/farmacocinética , Adulto , Inhibidores del Citocromo P-450 CYP3A , Inhibidores Enzimáticos/administración & dosificación , Femenino , Humanos , Masculino , Midazolam/administración & dosificación , Midazolam/análogos & derivados , Midazolam/sangre , Persona de Mediana Edad , Ritonavir/administración & dosificación , Simvastatina/administración & dosificación , Simvastatina/análogos & derivados , Simvastatina/sangre
11.
Clin Endocrinol (Oxf) ; 66(4): 579-85, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17371478

RESUMEN

OBJECTIVE: Andriol Testocaps is a new oral formulation of testosterone undecanoate (TU) for treatment of hypogonadism. As TU is taken up by the intestinal lymphatic system, both the presence and the composition of food influence the absorption. The aim of this study was to investigate the effect of food composition on the pharmacokinetics of oral TU. DESIGN: An open-label, single-centre, four-way crossover study. With a washout period of 6-7 days, 80 mg TU was administered in the morning 5 min after consuming each of four different meals in a randomized order (A: 230 kcal, 0.6 g lipid; B: 220 kcal, 5 g lipid; C: 474 kcal, 19 g lipid; D: 837 kcal, 44 g lipid). PATIENTS: Twenty-four postmenopausal volunteers. MEASUREMENTS: Serial blood samples were collected until 24 h after dosing to determine testosterone and dihydrotestosterone (DHT) by gas chromatography-mass spectroscopy (GC-MS). RESULTS: The bioavailability of testosterone after a low-calorie meal containing 0.6 g lipid or 5 g lipid was relatively low, the area under the concentration-time curve (AUC(0-tlast)) for testosterone being 30.7 and 43.5 nmol h/l, respectively. The bioavailability of testosterone after a meal containing 19 g lipid was considerably higher (AUC(0-tlast) = 146 nmol h/l), whereas increasing the lipid content to 44 g lipid did not further increase the bioavailability of testosterone (AUC(0-tlast) = 154 nmol h/l). CONCLUSION: Approximately 19 g of lipid per meal efficiently increases absorption of testosterone from oral TU. Therefore, coadministration with a normal rather than a fatty meal is sufficient to increase serum testosterone levels when using oral TU.


Asunto(s)
Grasas Insaturadas en la Dieta/administración & dosificación , Terapia de Reemplazo de Hormonas , Hipogonadismo/sangre , Hipogonadismo/tratamiento farmacológico , Testosterona/sangre , Testosterona/deficiencia , Anciano , Área Bajo la Curva , Disponibilidad Biológica , Estudios Cruzados , Femenino , Humanos , Absorción Intestinal , Persona de Mediana Edad , Posmenopausia/sangre , Testosterona/análogos & derivados , Testosterona/uso terapéutico , Congéneres de la Testosterona/uso terapéutico
12.
Vaccine ; 24(12): 2065-70, 2006 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-16337719

RESUMEN

A Phase I trial was performed to investigate the safety and immunogenicity of the third generation smallpox vaccine MVA-BN (IMVAMUNE), a highly attenuated clone derived from the Modified Vaccinia Virus Ankara strain 571, in naive and pre-immunized subjects. A total of 86 healthy subjects received the vaccine in five groups using different doses and routes of administration. All 38 subjects seroconverted in the groups receiving the highest dose (10(8) TCID50). All vaccinations were well tolerated with mainly mild or moderate pain at the injection site being the most frequent symptom. The results indicate that MVA-BN has the potential to be developed as an efficient and safe alternative to the conventional smallpox vaccines such as Lister-Elstree or Dryvax. Unique attributes render it a promising candidate for prophylactic mass immunization, even in subjects for whom conventional smallpox vaccines are contraindicated.


Asunto(s)
Inmunización Secundaria , Vacuna contra Viruela/administración & dosificación , Viruela/prevención & control , Virus Vaccinia/inmunología , Adulto , Método Doble Ciego , Humanos , Masculino , Persona de Mediana Edad , Seguridad , Vacuna contra Viruela/efectos adversos , Vacuna contra Viruela/genética , Vacuna contra Viruela/inmunología
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