Study of bioequivalence between two formulations of rivastigmine 6 mg capsules, in healthy volunteers after a single dose administration [Estudo de bioequivalência entre duas formulações de rivastigmina cápsulas de 6 mg, em voluntários sadios após administração de dose única]
Pedrazzoli Jr. J.,UNIFAG |
Zanin M.,UNIFAG |
Coelho E.C.,UNIFAG |
Marchioretto M.,UNIFAG |
And 5 more authors.
Revista Brasileira de Medicina | Year: 2012
The study was performed to compare the bioavailability/bioequivalence of two rivastigmine 6 mg capsule formulations (Rivastigmine from Aché Laboratórios Farmacêuticos S/A as test formulation and (Exelon®) from Novartis Biociências S/A as reference formulation) in 56 volunteers of both sexes. The study was conducted as an open randomized two period crossover design with a wash out phase of 7 days. Plasma samples from 46 from the 56 initially included volunteers were obtained over a 12 hour interval. Plasma concentrations of Rivastigmine were determined by LC-MS-MS equipment using zolpidem as internal standard. From the data obtained, the following pharmacokinetics parameters were calculated: AUC0-t, AUC 0-∞ and Cmax. Geometric mean ratios of Rivastigmine/Exelon® capsule 6 mg was 100,97% for AUC0-t, 101,38% for AUC0-∞ and 89,01% for Cmax; the 90% confidence intervals were 93,20% - 109,3993.65% - 109.75% and 81,10% - 97,70%, respectively. Since the 90% confidence intervals for Cmax, AUC 0-t and AUC0-∞ were within the range of 80% - 125% proposed by Food and Drug Administration and ANVISA (the National Health Surveillance Agency of Brasil), it was concluded that Rivastigmine 6 mg Capsule was bioequivalent to Exelon® 6 mg Capsule, and so the test product can be considered interchangeable in normal medical practice. © Copyright Moreira Jr. Editora.
Real Martinez C.A.,Sao Francisco Medical School |
Mendes Bartocci P.C.,Medical Course |
Do Carmo C.V.,Sao Francisco Medical School |
Pereira J.A.,Sao Francisco Medical School |
And 2 more authors.
Scandinavian Journal of Gastroenterology | Year: 2010
Objective. The aim of this study was to investigate the levels of oxidative DNA damage and p53 mutations in an experimental model of diversion colitis. Material and methods. Sixty rats were divided into three groups with 20 animals in accordance with the sacrifice was carried out 6, 12 and 18 weeks. For each group, 15 animals were subjected to diversion of the fecal stream through colostomy in the left proximal colon and distal mucous fistula (experimental group), and five to a laparotomy without deviation of the fecal stream (control group). The presence of colitis was evaluated by inflammatory grading scale. Mutations in the p53 protein were evaluated by immunohistochemistry with primary antibody with cross-reactivity for rats. The oxidative DNA damage was measured using the comet assay. To statistical analysis were used the Student's t, Mann-Whitney and Kruskal-Wallis test adopting a significance level of 5% (p < 0.05). Results. Colon segments without fecal stream showed greater degree of inflammation when compared to animals with preserved fecal stream (p= 0.01). The levels of oxidative stress were significantly higher in segments without fecal stream (p < 0.0001) and increased with the time of fecal diversion (p= 0.007). The levels of oxidative DNA damage are directly related to tissue degree of inflammation. There were no mutations in the p53 protein in the segments without fecal stream regardless of time of exclusion considered. Conclusion. Despite higher levels of oxidative damage to nuclear DNA on segments without fecal stream that developed colitis mutations in the p53 protein were not detected. © 2010 Informa UK Ltd.