Tadalafil: a novel treatment for erectile dysfunction
a Department of Urology, AP-HP, Centre Hospitalier Universitaire de Bicêtre, Le Kremlin-Bicêtre, France
b Eli Lilly and Company Ltd, Lilly Research Centre, Erl Wood Manor, Windlesham Surrey, U.K.
* Correspondence: François Giuliano, MD, PhD, Department of Urology, CHU de Bicêtre, 78 rue du Général Leclerc, 94270 Le Kremlin-Bicêtre Cedex, France.
Abstract
Tadalafil, a potent, selective and reversible inhibitor of phosphodiesterase type 5 that is under review as an oral therapy for erectile dysfunction, has a time to maximum concentration of 2 h and a half-life of 17·5 h. Systemic tadalafil exposure was not clinically significantly altered by age or diabetes. Food did not alter the rate and extent of absorption of tadalafil, and no restrictions regarding food or alcohol intake were imposed on patients in tadalafil clinical trials. Furthermore, the time of dosing had no significant effect on the systemic distribution of tadalafil. Integrated analyses of data from five phase III trials demonstrated that tadalafil at doses from 5 mg to 20 mg significantly improved erectile function (vs placebo) by all efficacy measures. Tadalafil was safe and well tolerated in the phase III studies, with headache and dyspepsia being the most frequent adverse events. Additionally, in a separate study of patients with erectile dysfunction and diabetes, tadalafil 10 mg and 20 mg significantly improved all efficacy measures as compared with placebo.
Key Words: Diabetes efficacy erectile dysfunction pharmacodynamics pharmacokinetics safety tadalafil
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