Erectile Dysfunction

• For additional information regarding investigative sites for this trial, contact 1-877-CTLILLY (1-877-285-4559, 1-317-615-4559) Mon - Fri from 9 AM to 5 PM Eastern Time (UTC/GMT - 5 hours, EST), or speak with your personal physician. — Genthin, Germany

• For additional information regarding investigative sites for this trial, contact 1-877-CTLILLY (1-877-285-4559, 1-317-615-4559) Mon- Fri from 9 AM to 5 PM Eastern Time (UTC/GMT - 5 hours, EST), or speak with your personal physician. — Plymouth, United Kingdom

• Seoul National University Hospital — Seoul, South Korea

• Seoul National University Hospital — Seoul, South Korea

• Medical Affiliated Research Center — Huntsville, Alabama, United States
• The Male Clinic — Beverly Hills, California, United States
• South Orange County — Laguna Woods, California, United States
• California Profession Research — Newport Beach, California, United States

• Pfizer Investigational Site — Oslo, Norway
• Pfizer Investigational Site — Belfast, Northern Ireland, United Kingdom

• Pfizer Investigational Site — Birmingham, Alabama, United States
• Pfizer Investigational Site — Birmingham, Alabama, United States
• Pfizer Investigational Site — Birmingham, Alabama, United States
• Pfizer Investigational Site — Mesa, Arizona, United States

Not specified

• Erasmus MC — Rotterdam, Netherlands

• RDC Clinical Pty Ltd — Brisbane, Queensland, Australia