Official Title: “A Randomized, Open-Label, Crossover, Multicenter, Single Dose Comparator Study Evaluating Onset Of Penile Rigidity In Men With Erectile Dysfunction Who Are Treated With Viagra (Sildenafil Citrate) And Cialis (Tadalafil)”

The objective of this study was to determine and compare the minimum time required to achieve penile rigidity greater than or equal to 60% at the base of the penis that is sustained for at least 3 minutes measured by Rigiscan®, following visual sexual stimulation post dose of 100 mg sildenafil citrate and 20 mg tadalafil in men with erectile dysfunction (ED).

Study Type: Interventional

Study Design: Treatment, Randomized, Open Label, Crossover Assignment, Efficacy Study

Intervention(s) in this Clinical Trial

• Drug: tadalafil
  • tadalafil 20 mg tablet by mouth for 2 doses (at Week 0 and Week 1)
• Drug: sildenafil
  • sildenafil 100 mg tablet by mouth for 2 doses (at Week 0 and Week 1)

Arms, Groups and Cohorts in this Clinical Trial

• Active Comparator: Arm 1
• Active Comparator: Arm 2

Primary Measures

• The primary efficacy variable was time to onset of penile rigidity greater than or equal to 60% at the base of the penis, measured by Rigiscan, that was sustained for at least 3 minutes following visual sexual stimulation
  • Time Frame: Screening, Week 0, and Week 1
    Safety Issue?: No

Secondary Measures

• The percentage of subjects who achieved penile rigidity greater than or equal to 60% at the base of the penis, measured by Rigiscan, that was sustained for at least 5 minutes following visual sexual stimulation
  • Time Frame: Screening, Week 0, and Week 1
    Safety Issue?: No
• Time to onset of penile rigidity greater than or equal to 60% at the base of the penis, measured by Regiscan, that was sustained for at least 5 minutes following visual sexual stimulation
  • Time Frame: Screening, Week 0, and Week 1
    Safety Issue?: No
• The percentage of subjects who achieved penile rigidity greater than or equal to 60% at the base of the penis, measured by Regiscan, that was sustained for at least 3 minutes following visual sexual stimulation
  • Time Frame: Screening, Week 0, and Week 1
    Safety Issue?: No

Inclusion Criteria:

• Included subjects were 18 years of age or older
• A clinical diagnosis of erectile dysfunction
• Known responders to either 100 mg sildenafil or 20 mg tadalafil.

Exclusion Criteria:

• Excluded were subjects who were unable to achieve penile rigidity of greater than or equal to 20% at the base of the penis that was sustained for at least 3 minutes
• Subjects who are able to achieve penile rigidity of greater than or equal to 60% at the base of the penis that was sustained for for at least 2 minutes or subjects who are able to achieve penile rigidity of greater than or equal to 80% at the base of the penis that is sustained for for at least 1 minute measured by Rigiscan®, at screening with no therapy, within 60 minutes following visual sexual stimulation
• Subjects currently using any commercially available treatments for erectile dysfunction
• Subjects on nitrates.

Gender Eligibility for this Clinical Trial: Male

Minimum Age for this Clinical Trial: 18 Years

Maximum Age for this Clinical Trial: N/A

Are Healthy Volunteers Accepted for this Clinical Trial?: No

Lead Sponsor: Pfizer

Overall Clinical Trial Officials and Contacts

Pfizer CT.gov Call Center Study Director Pfizer  

Information obtained from ClinicalTrials.gov on September 04, 2008

Link to the current ClinicalTrials.gov record. http://clinicaltrials.gov/show/NCT00644956

Study ID Number: A1481183

ClinicalTrials.gov Identifier: NCT00644956

Health Authority: United States: Food and Drug Administration

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