A STUDY IN PATIENTS WITH ERECTILE DYSFUNCTION COMPARING DIFFERENT FORMULATIONS OF PROSTAGLANDIN-E1

Purpose: Prostaglandin E1 sterile powder and sterile solution are 2 ne w formulations of exogenous prostaglandin E1 that are more convenient for auto-injection therapy for erectile dysfunction than the presently used pediatric sterile solution. Therefore, the pharmacodynamic profi les of intracavernous prostaglandin E1 sterile powder and nonalcohol s terile solution were compared with the pediatric sterile solution in m en with erectile dysfunction who were known to be stable responders to intracavernous prostaglandin E1. Materials and Methods: Based on the dose used at home, patients were randomized to 1 of 5 dose groups: 0 m u g. (placebo), 2.5 mu g., 5 mu g., 10 mu g. or 20 mu g. Each patient received a single injection of the same dose of each of the 3 formulat ions. The primary pharmacodynamic end points were clinical evaluation of erectile response, RigiScan dagger real-time evaluation of erectile response and patient evaluation of erectile response. Results: No sig nificant differences were identified among the formulations for any of these end points, either by comparison among all active doses or by c omparison at each prostaglandin E1 dose level. There was also little o r no intra-patient variation in dose response and the inter-dose varia tion in response between patients was not significant. Pharmacodynamic end paints were well intercorrelated, although assessment of erectile response by the patients tended to be more positive than that by Rigi Scan or clinical evaluation. There were no major side effects. Penile pain on injection and/or during erection occurred in 9 to 17% of the p atients according to the formulations. However, penile pain was also r eported by 11% of the placebo-treated patients. Conclusions: The 3 for mulations of prostaglandin E1 showed equivalence and were safe for the treatment of erectile dysfunction with respect to side effects.