This is a multicenter, randomized, double blind, placebo-controlled, parallel design study to evaluate the efficacy and safety of 2.5mg and 5mg tadalafil taken once daily in men with erectile dysfunction.

• Drug: tadalafil
  2.5 mg or 5 mg tadalafil tablet taken by mouth once a day for 24 weeks. Followed by an open label extension where all patients receive 5 mg doses.
  Other Names:

  • LY450190
  • Cialis
  • IC351
• Drug: placebo
  Placebo tablet taken by mouth once a day for 24 weeks. Placebo patient will receive 5 mg tadalafil tablet during the open label extension.

• 1: Placebo Comparator
  placebo tablet
  Intervention: Drug: placebo
• 2: Active Comparator
  2.5 mg tadalafil tablet
  Intervention: Drug: tadalafil
• 3: Active Comparator
  5 mg tadalafil tablet
  Intervention: Drug: tadalafil

Inclusion Criteria:

• Men with erectile dysfunction
• At least 18 years of age

Exclusion Criteria:

• Certain chronic medical conditions including cardiac disease, congestive heart failure, kidney or liver disease, cancer and HIV
• A history of certain impotence disorders
• History of specified pelvic surgery
• Any significant genital abnormality identified at the start of the study