@article{Kanjanawart_Kongyingyoes_Gaysornsiri_Tangsucharit_Puapairoj_Vannaprasaht_Tiamkao_Tassaneeyakul_2013, title={Bioequivalence and Pharmacokinetic Study of Sildenafil in Healthy Thai Male Volunteers}, volume={23}, url={https://li01.tci-thaijo.org/index.php/SRIMEDJ/article/view/13051}, abstractNote={<p><strong><span style="text-decoration: underline;">Background:</span></strong> Sildenafil is a popular drug used for improving penile erectile function that has been commercially available through several manufacturers and distributors in Thailand.  Therefore, it is necessary to study bioequivalence of the drugs obtained from the original manufacture and from a local manufacturer to ascertain that they can be medicated interchangeably.</p> <p><strong><span style="text-decoration: underline;">Objective</span></strong><span style="text-decoration: underline;">:</span> To determine whether two sildenafil preparations: Test (Erec<sup>â</sup>, Unison Laboratories, Co., Ltd., Thailand) and reference, (Viagra<sup>Ò</sup>, Pfizer Pty Limited., Australia) are bioequivalent.</p> <p><strong><span style="text-decoration: underline;">Design</span></strong><span style="text-decoration: underline;">:</span> Single oral dose and double-blind randomized two-way crossover.</p> <p><strong><span style="text-decoration: underline;">Population and samples</span></strong><span style="text-decoration: underline;">:</span> Fifteen healthy Thai male volunteers.</p> <p><strong><span style="text-decoration: underline;">Setting</span></strong><span style="text-decoration: underline;">:</span> Department of pharmacology, and Srinagarind Hospital, Faculty of Medicine, Khon Kaen University.</p> <p><strong><span style="text-decoration: underline;">Methods:</span></strong> The subjects received either 100 mg of the reference or test formulation.  Blood samples were collected from catheter at several time points after sildenafil administration up to 12 hours. The bioequivalence between the two formulations was assessed by comparison of the peak plasma concentrations (C<sub>max</sub>) and area under the curve of time, from 0 to the last measurable concentration (AUC<sub>0-t last</sub>).</p> <p><strong><span style="text-decoration: underline;">Results</span></strong><span style="text-decoration: underline;">:</span> All subjects were well tolerated and presented no serious side effect.  Statistical analysis revealed that the 90% confident intervals (CI) for the ratios between test and reference drugs of the log transformed the C<sub>max</sub> (0.8377-1.1985) and AUC<sub>0-t last</sub> (0.8610-1.1590), are within the Food and Drug Administration Guideline range of bioequivalence (0.80 to 1.25).</p> <p><strong><span style="text-decoration: underline;">Conclusions</span></strong><span style="text-decoration: underline;">:</span> It can be concluded that the 100 mg formulation of Test (Erec<sup>â</sup>) is bioequivalent to the Reference.</p> <p><strong><span style="text-decoration: underline;">Keywords:</span></strong><strong> </strong>sildenafil, bioequivalence<strong></strong></p>}, number={1}, journal={Srinagarind Medical Journal}, author={Kanjanawart, Sirimas and Kongyingyoes, Bunkerd and Gaysornsiri, Dhanu and Tangsucharit, Panot and Puapairoj, Prapawadee and Vannaprasaht, Suda and Tiamkao, Siriporn and Tassaneeyakul, Wichittra}, year={2013}, month={Nov.}, pages={38–44} }