Efficacy & Safety of Single Dose Alprostadil Cream (2 Concentrations Enhancer) to Vehicle in Men w/Erectile Dysfunction

Inclusion Criteria: * Male subject aged 40 or older of any race * History of ED (erectile dysfunction) of at least 3 months duration defined as inability to attain \& maintain an erection of the penis sufficient to permit satisfactory sexual intercourse * Completed and signed informed consent prior to any study related procedures Exclusion Criteria: * History/presence any significant disease that Investigator feels will interfere with course of the study * Anatomic deformity of penis * History/presence alcoholism or drug abuse/dependence within past 2 years (discretion of Investigator) * Participation in investigational study drug trial within 30 days prior to randomization