The phosphodiesterase type 5 (PDE5) inhibitor vardenafil (Levitra) improves symptoms and digital blood flow, both at room temperature and during a cold-exposure test, in some patients with Raynaud disease, results of a pilot study suggest.

Raynaud disease can be difficult to treat, especially among patients whose disease is secondary to connective tissue diseases, such as systemic sclerosis. In the January 23rd issue of the Archives of Internal Medicine, Dr. Stephan Rosenkranz and colleagues at Universitat zu Koln in Germany suggest that, because PDE5 inhibition is used to treat erectile dysfunction on the basis of its vasodilatory properties, it would be of benefit in patients with Raynaud disease.

They recruited seven patients with primary Raynaud disease and 33 with secondary Raynaud disease. Twelve of the patients were smokers. During the 2-week open-label study, the subjects took vardenafil 10 mg twice daily for 2 weeks.

According to the team’s report, 28 (70%) patients exhibited reduced digital blood flow based on laser Doppler measurements. In this subset, the authors observed a highly significant increase after 2 weeks in digital blood flow at room temperature (30.0%), and in blood flow during a cold exposure test (35.1%).

The total daily duration of Raynaud disease-related attacks was reduced in 24 (60%), and the number and severity of attacks were reduced in 20 (50%) and 21 (53%). Responses were similar in smokers and nonsmokers, and in those with primary versus secondary Raynaud disease.

“When compared with other studies, the response rate and therapeutic efficacy of vardenafil were at least equal to those of established agents, such as calcium channel blockers,” Dr. Rosenkranz’s team writes.

They point out that because calcium channel blockers and PDE5 inhibitors exert their vasodilative properties through distinct mechanisms, it is possible that combination therapy may enhance the effect of either agent alone. Placebo-controlled trials are warranted, they add.

Arch Intern Med 2006;166:231-233.