Long-term, multicenter study of the safety and efficacy of topical alprostadil cream in male patients with erectile dysfunction.

INTRODUCTION: Alprostadil is approved for treatment of male erectile dysfunction (ED) by injection or urethral insertion. Topical delivery of alprostadil offers an improved alternative.

AIM: To evaluate the long-term safety and efficacy of topical alprostadil cream.

METHODS: This was a multicenter, open-label, long-term study in 1,161 patients (998 double-blind rollover; 163 naïve) with ED. For the first 4 weeks, patients could administer eight doses of 200 mcg alprostadil to the penis meatus before intercourse (up to 2 per/week). Patients then self-selected to administer 300 or 100 mcg doses if hypo-responsive or hyper-responsive, respectively, or 200 mcg if no change, for up to 9 months (2 doses/week).

MAIN OUTCOME MEASURES: Safety evaluated patient/partner adverse events (AEs), changes in vital signs, clinical laboratory tests, physical examinations, and electrocardiograms. Efficacy assessed International Index of Erectile Function, Sexual Encounter Profile, Patient Self Assessment of Erection, and Global Assessment Questionnaire.

RESULTS: Approximately 12% of patients discontinued due to hypo-/hyper-responsiveness, 16% withdrew consent for a variety of reasons, and less than 5% discontinued because of AEs. The majority of patients (73%) selected 300 mcg alprostadil as the final dose. The most common AEs involved application site burning or erythema (12.2%), meatal or glans pain (4.4%), and prolonged or painful erection (1.3%). Only 5 (0.4%) patients reported a prolonged erection of >or=4 hours (priapism). Vaginal burning or itching (2.1%) was reported most frequently by partners. The majority of patients (74%) demonstrated an overall improvement in erectile function on most end-points, especially after adjusting dose strength to their individual responsiveness.

CONCLUSIONS: Topical alprostadil cream was considered effective and safe by most patients and their partners, with most AEs limited to the application site. Dose adjustment to 300 mcg alprostadil facilitated the greatest improvement in erectile function in the majority of patients. A separate report will integrate patient data from the open-label extension and prior double-blind studies.