Bioequivalence evaluation of tinidazole 500 mg tablets / Avaliação de bioequivalência de comprimidos contendo 500 mg de tinidazol

AUTOR(ES)
DATA DE PUBLICAÇÃO

2005

RESUMO

Tinidazole, 1-[2-(ethylsulphonyl)ethyl]-2-methyl-5-nitroimidazole, is a member of the 5-nitroimidazole class of antimicrobial agents with amoebicidal, giardicidal, trichomonicidal and anaerobic activity. The purpose of this study was to evaluate the bioequivalence of two brands of tinidazole 500mg tablets in healthy human volunteers. The procedure of bioequivalence between the test product (Amplium® - FARMASA) and reference product (Pletil® - Pharmacia do Brasil Ltda) was a randomized, crossover and open study. The medication was administered in a single dose of 500 mg of tinidazole to 24 healthy volunteers. Blood samples were collected until 72 hours after administration and analised using a validated high-performance liquid chromatographic method with UV detection. The average plasmatic decay curves obtained for the test product (Amplium® - FARMASA) and reference product (Pletil® - Pharmacia do Brasil Ltda) were similar, in the same way as were the pharmacokinetic parameters Cmax (reference: 11.34 µg/mL; test: 11.11 µg/mL), tmax (reference: 1.67 h; test: 1.71 h), AUC0-t (reference: 201.92 µgxh/mL; test: 198.15 µgxh/mL), AUC0-∞ (reference: 208.25 µg/mL; test: 203.80 µgxh/mL) and t(½)el (reference = 14.05 hours, test = 13.91 hours). The multivariate analysis accomplished through analysis of variance (ANOVA), for assessment of product, group and period effects, revealed the absence of any of these effects in the present study, indicating that the crossover design was properly performed. j The 90% confidence intervals for the ratio of Cmax (93.9 % - 102.6 %), AUC0-t (94.9 % - 101.1 %) and AUC0-∞ (94.6 % - 100.8 %) values for the test and reference products are within the 80 - 125 % interval proposed by FDA and ANVISA. Statistical comparison of AUC0-t , AUC0-∞ and Cmax clearly indicated no significant difference between the two brands of tinidazole 500 mg tablets. Based on the pharmacokinetic and statistical results of this study, we can conclude that the two products are bioequivalent, and can be considered interchangeable in medical practice.

ASSUNTO(S)

tinidazol metronidazol metronidazole tinidazole bioequivalence high-performance liquid chromatography cromatografia líquida de alta eficiência bioequivalência

ACESSO AO ARTIGO

Documentos Relacionados