[Comparison study of two glimepiride formulations bioavailability in healthy volunteers of both sexes after a single dose administration]. / Estudo comparativo da biodisponibilidade relativa de duas formulações de glimepirida em voluntários sadios de ambos os sexos após administração de uma dose única de um comprimido de 4 mg.

OBJECTIVE: To compare the bioavailability of two glimepiride 4-mg tablet formulation in 26 healthy volunteers of both sexes. MATERIAL AND METHODS: The study was conducted open with randomized two-period crossover design and a 14-day washout period. Samples were obtained over a 48-hour interval. Glimepiride concentrations were analyzed by LC-MS-MS. From the glimepiride plasma concentration versus time curves the following pharmacokinetic parameters were obtained: AUC(0-last), AUC(0-t), AUC(0-infinity), Ke, T1/2, Cmax, and Tmax. RESULTS: Geometric mean of Glimepirida/Amaryl 4 mg was 102.35% for AUC(0-t), 102.35% for AUC(0-infinity) and 99.31% for Cmax. The 90% CI was 92.62-109.55%; 95.62-109.55% e 88.60-111.32%, respectively. CONCLUSION: Since the 90% CI for both Cmax, AUC(0-t), and AUC(0-infinity) were within the interval of 80-125%, it was concluded that both formulations were bioequivalent, according to both the rate and extent of absorption.

Estudo comparativo da biodisponibilidade relativa de duas formulações de glimepirida em voluntários sadios de ambos os sexos após administração de uma dose única de um comprimido de 4 mg / Comparison study of two glimepiride formulations bioavailability in healthy volunteers of both sexes after a single dose administration

OBJETIVO: Comparar a biodisponibilidade de duas formulações de glimepirida em 26 voluntários sadios de ambos os sexos. MATERIAL E MÉTODOS: O estudo foi aberto, cruzado e randomizado com dois períodos e wash out de 14 dias. As amostras foram obtidas em um intervalo de 48 horas. As concentrações de glimepirida foram analisadas por HPLC MS/MS. Das curvas de concentração de glimepirida no plasma versus tempo, foram obtidos os seguintes parâmetros farmacocinéticos: ASC(0-t), ASC(0-∞), Cmax, Ke, Tmax e T1/2. RESULTADOS: A razão entre as média geométricas de Glimepirida/Amaryl® 4 mg foi de 102,35 por cento para ASC(0-t); 102,35 por cento para ASC(0-∞) e 99,31 por cento para Cmax. Os intervalos de confiança de 90 por cento (IC 90 por cento) foram de 92,62-109,55 por cento; 95,62-109,55 por cento e 88,60-111,32 por cento, respectivamente. CONCLUSÃO: Como o IC 90 por cento para Cmax, ASC(0-t) e ASC(0-∞) estava dentro do intervalo de 80-125 por cento, concluiu-se que ambas as formulações foram bioequivalentes de acordo com o grau e a extensão de sua absorção.

OBJECTIVE: To compare the bioavailability of two glimepiride 4-mg tablet formulation in 26 healthy volunteers of both sexes. MATERIAL AND METHODS: The study was conducted open with randomized two-period crossover design and a 14-day washout period. Samples were obtained over a 48-hour interval. Glimepiride concentrations were analyzed by LC-MS-MS. From the glimepiride plasma concentration versus time curves the following pharmacokinetic parameters were obtained: AUC(0-last), AUC(0-t), AUC(0-∞), Ke, T1/2, Cmax, and Tmax. RESULTS: Geometric mean of Glimepirida/Amaryl® 4 mg was 102.35 percent for AUC(0-t), 102.35 percent for AUC(0-∞) and 99.31 percent for Cmax. The 90 percent CI was 92.62-109.55 percent; 95.62-109.55 percent e 88.60-111.32 percent, respectively. CONCLUSION: Since the 90 percent CI for both Cmax, AUC(0-t), and AUC(0-∞) were within the interval of 80-125 percent, it was concluded that both formulations were bioequivalent, according to both the rate and extent of absorption.

Pharmacokinetics and pharmacodynamics of a nitric oxide-releasing derivative of enalapril in male beagles.

1. Pharmacological compounds that release nitric oxide (NO) have been useful tools in the evaluation of the broad role of NO in physiopathology and therapeutics. The present study compared the pharmacokinetics and pharmacodynamics of enalapril and an NO-releasing enalapril molecule (NCX899) in conscious male beagles. The effects of both enalapril and NCX899 in the arterial hypertension and bradycardia induced by acute NO inhibition in anaesthetized dogs were also investigated. 2. Dogs received either NCX899 (4 micromol/kg, i.v.) or enalapril (4 micromol/kg, i.v.), after which plasma concentrations of the analytes and metabolites were quantified by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). 3. In the NCX899 group, the area under the time-course curve (AUC(0-24h)) was 29.18 +/- 4.72, 229.37 +/- 51.32 and 5159.23 +/- 514.88 microg.h/L for the analytes nitro-enalapril, enalapril and enalaprilat, respectively. In the enalapril group, the AUC(0-24h) was 704.53 +/- 158.86 and 4149.27 +/- 847.30 microg.h/L for the analytes enalapril and enalaprilat, respectively. Statistical analysis of data from both groups showed a significant difference for the analyte enalapril, but not for enalaprilat. Moreover, NCX899 and enalapril were equally effective in inhibiting the activity of serum angiotensin-converting enzyme. 4. In anaesthetized dogs, i.v. administration of the NO synthase (NOS) inhibitor N(G)-nitro-l-arginine methyl ester (l-NAME; 0.1-10 mg/kg) significantly elevated arterial blood pressure, with concomitant bradycardia. The compound NCX899 significantly attenuated both arterial hypertension and bradycardia, whereas enalapril had no significant effect. 5. In conclusion, the present results showed that the NO-releasing derivative of enalapril NCX899 presents a pharmacokinetic/pharmacodynamic relationship similar to its parent compound enalapril. Moreover, NCX899 (but not enalapril) was effective in protecting against the cardiovascular changes induced by acute NOS inhibition.