Arzneimittelforschung 2008; 58(3): 122-125
DOI: 10.1055/s-0031-1296480
Vasodilators
Editio Cantor Verlag Aulendorf (Germany)

Bio equivalence Study of Two Tablet Formulations of Sildenafil

Ana Cristina Franco Spínola
1   Medical Department, Grupo Tecnimede, Prior Velho, Portugal
,
Susana Almeida
1   Medical Department, Grupo Tecnimede, Prior Velho, Portugal
1   Department of Pharmacology and Therapeutics, Universidad Autonoma de Barcelona, Barcelona, Spain
,
Augusto Filipe
1   Medical Department, Grupo Tecnimede, Prior Velho, Portugal
,
Mario Tanguay
1   Anapharm, Quebec City, Quebec, Canada
,
Mercedes Yritia
1   Anapharm Europe S.L., Barcelona, Spain
› Author Affiliations
Further Information

Publication History

Publication Date:
15 December 2011 (online)

Abstract

This study was conducted in order to assess the bioequivalence of two tablet formulations containing 100 mg sildenafil (1-[4-ethoxy-3-(6,7-dihydro-l-,ethyl-7-oxo-3-propyl-lH-pyrazolo[4,3-d]pyrimi-din-5-yl)phenylsulphonyl]-4-methyl piperazine, CAS 139755-83-2). Twenty-eight healthy subjects were enrolled in a single-centre, randomised, single-dose, open-label, 2-way crossover study, with a minimum washout period of 7 days. Plasma samples were collected up to 18.0 h post-dosing. Sildenafil levels were determined by reverse liquid chromatography coupled with tandem mass spectrometry detection (LC-MS/MS). Pharmacokinetic parameters used for bioequivalence assessment [area under the concentration-time curve from time zero to time of last nonzero concentration (AUClast) and maximum observed concentration (Cmax) were main evaluation criteria; however, the area under the concentration-time curve from time zero to infinity (AUCinf) was also analysed] were determined from the sildenafil concentration data using non-compartmental analysis. The 90% confidence intervals (obtained by analysis of variance, ANOVA) were 86.70–108.19 for Cmax, 86.67–99.26 for AUClast and 87.19–99.82 for AUCinf, within the predefined ranges. Bioequivalence between the two formulations was concluded both in terms of rate and extent of absorption.

 
  • Literature

  • 1 Gupta M, Kovar A, Meibohm B. The clinical pharmacokinetics of phossphodiesterase-5 inhibitors for erectile dysfunction. J Clin Pharmacol. 2005; 45: 987-1003
  • 2 Mandal U, Musmade P, Chakraborty M, Rajan S, Pal MCTK, Chataraj TK. Bioequivalence study of sildenafil citrate tablets in healthy human volunteers. Boll Chim Farm. 2004; November 9: 345-49
  • 3 European Medicines Agency. European public assessment report (EPAR) Viagra. [Online]. 2005 [cited 2007 Nov 26]; Available from: http://www.emea.europa.eu/humandocs/PDFs/EPAR/Viagra/113698en6.pdf.
  • 4 Salonia A, Rigatti P, Montorsi F. Sildenafil in erectile dysfunction: a critical review. Curr Med Res Opin. 2003; 19 (4) 241-262
  • 5 Mehrotra N, Gupta M, Kovar A, Meibohm B. The role of pharmacokinetics and pharmacodynamics in phosphodi-esterase-5 inhibitor therapy. Int J Impot Res. 2007; 19: 253-264
  • 6 Committee for Proprietary Medicinal Products (CPMP). Note for guidance on the investigation of bioavailability and bioequivalence. CPMP/EWP/QWP/1401/98. July 2001.
  • 7 ICH Harmonised Tripartite Guideline. Guideline for good clinical practice E6 (Rl). 1996.
  • 8 Guidance for Industry. Bioanalytical Method Validation. Food and Drug Administration, Center for Drug Evaluation and Research (CDER). May 2001.