Comparative trial of treatment satisfaction, efficacy and tolerability of sildenafil versus apomorphine in erectile dysfunction--an open, randomized cross-over study with flexible dosing
Related Experiment Video
Updated: Jul 16, 2026

Treatment Model for Young Patients with Psychogenic Erectile Dysfunction and Resultant Infertility
Published on: May 30, 2025
Harmut Porst1, Hermann M Behre, Andreas Jungwirth
1Pfizer Pharma GmbH, 76032 Karlsruhe, Germany.
Objective:
Sildenafil and apomorphine are oral agents for the improvement of erection hardness. The aim of the study was a direct comparison of the two compounds under clinical routine conditions.
Methods:
131 previously untreated men with erectile dysfunction (ED) were enrolled in a cross-over trial and randomly allocated to 50 mg sildenafil or 2 mg apomorphine. Dose-adaptation was allowed as required.
Results:
Improvements in rigidity, the capacity to get and maintain an erection, and sexual confidence were statistically significantly larger with sildenafil (p <0.0001). 90% of the men were satisfied with sildenafil as compared to 46% with apomorphine. At study end, 95% of the patients preferred sildenafil. Both agents were well tolerated.
Conclusions:
In this cross-over comparison under clinical routine conditions men reported superior efficacy of sildenafil vs apomorphine together with a statistically significantly higher treatment satisfaction.
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