Efficacy and safety of two dosing regimens of tadalafil and patterns of sexual activity in men with diabetes mellitus and erectile dysfunction: Scheduled use vs. on-demand regimen evaluation (SURE) study in 14 European countries

J Sex Med. 2006 May;3(3):512-20. doi: 10.1111/j.1743-6109.2006.00249.x.


Aim: The aim of this article is to evaluate the efficacy and safety of 20-mg tadalafil taken on demand or three times per week and its effect on the sexual activity of patients with diabetes mellitus and erectile dysfunction (ED).

Methods: The scheduled use vs. on-demand regimen evaluation (SURE) was a randomized, crossover, open-label study with 4,262 patients in 14 European countries. The efficacy measures for the 762 patients with diabetes and ED included changes from baseline in the erectile function (EF) domain of the International Index of Erectile Function (IIEF), and the proportion of "yes" responses to patient Sexual Encounter Profile (SEP) questions 2 (SEP2) and 3 (SEP3). The treatment satisfaction was measured with responses to SEP question 4 (SEP4) and SEP question 5 (SEP5), and sexual attempts data were collected. Patient preference for either regimen was determined by the treatment preference question (TPQ).

Results: At end point on both regimens, the mean IIEF EF domain score was 22, and >40% of the patients had a normal EF domain score (> or =26). The proportion of "yes" responses was > or =73% for SEP2 (penetration), > or =58% for SEP3 (successful intercourse), >46% for SEP4 (hardness of erection), and > or =45% for SEP5 (overall satisfaction). Efficacy was maintained up to 36 hours post-dosing. More than 70% of sexual attempts while on the three-times-per-week regimen and approximately 50% of the attempts on the on-demand treatment occurred >4 hours post-dosing. Tadalafil was well tolerated, with dyspepsia and headache as the most frequent adverse events reported. Treatment preference was 57.2% for on demand and 42.8% for three times per week.

Conclusions: Tadalafil, when taken on demand or three times per week, is efficacious and safe in men with diabetes and ED.

Publication types

  • Controlled Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Carbolines / administration & dosage*
  • Carbolines / adverse effects
  • Comorbidity
  • Cross-Over Studies
  • Diabetes Mellitus / epidemiology*
  • Dose-Response Relationship, Drug
  • Drug Administration Schedule
  • Erectile Dysfunction / drug therapy*
  • Erectile Dysfunction / epidemiology*
  • Europe / epidemiology
  • Humans
  • Male
  • Middle Aged
  • Patient Satisfaction / statistics & numerical data*
  • Penile Erection
  • Phosphodiesterase Inhibitors / administration & dosage
  • Phosphodiesterase Inhibitors / adverse effects
  • Sexual Behavior / statistics & numerical data*
  • Surveys and Questionnaires
  • Tadalafil
  • Treatment Outcome
  • Vasodilator Agents / administration & dosage
  • Vasodilator Agents / adverse effects


  • Carbolines
  • Phosphodiesterase Inhibitors
  • Vasodilator Agents
  • Tadalafil