Vardenafil rescue rates of sildenafil nonresponders: Objective assessment of 327 patients with erectile dysfunction

Objectives. To prospectively investigate whether vardenafil can effectively treat patients for whom sildenafil (100 mg) has failed. The introduction of two new oral phosphodiesterase type 5 inhibitors (tadalafil and vardenafil) raises the question of whether the new agents will permit us to treat sildenafil nonresponders with another oral agent. Methods. Patients were seen at one institution during a 5-year period. A total of 327 patients complaining of sildenafil-refractory erectile dysfunction underwent intracavernous pharmacologic injection and color duplex Doppler ultrasonography. Subsequently 59 of these men tried vardenafil home dosing. Results. Of the 327 men in whom sildenafil failed, 16% were younger than 50, 21% were 51 to 60, 34% were 61 to 70, and 28% were older than 70 years. The Doppler diagnoses were arterial insufficiency in 154 (47%), mixed vascular insufficiency in 73 (22%), and cavernous venous occlusive disease in 57 (17%). Forty-three men (13%) had normal erectile responses to prostaglandin E, (10 to 20 mu g). Of the 59 men who tried vardenafil, 19% were younger than 50, 17% were 51 to 60, 40% were 61 to 70, and 23% were older than 70 years. The Doppler diagnoses were arterial insufficiency in 28 (42%), mixed vascular insufficiency in 10 (19%), and cavernous venous occlusive disease in 15 (29%). Six men (8%) had normal erectile responses to prostaglandin El. Only 7 (12%) of the 59 men reported that home vardenafil dosing resulted in successful intercourse. Conclusions. An appropriate diagnostic evaluation and subsequent treatment algorithm have yet to be established for those for whom phosphodiesterase type 5 inhibitors fail. We found that most sildenafil nonresponders had severe arterial insufficiency and were older, with 62% older than 60 years. Our preliminary experience suggests that only a small percentage (12%) of sildenafil nonresponders can be salvaged with vardenafil.