NEW YORK (Reuters Health) – Vardenafil is an effective treatment for patients with Raynaud phenomenon (RP), a new crossover study funded by Bayer Healthcare shows.
“PDE5 inhibitors have been shown now many times to be an effective and well tolerated treatment option in patients with severe symptoms due to Raynaud phenomenon,” Dr. Evren Caglayan of the University of Cologne in Germany, one of the study’s authors, told Reuters Health.
“This therapeutic option should be considered more frequently in these patients,” he added.
RP may be triggered by cold or stress, and is thought to result from vasospasms that reduce blood flow to the fingers and toes. Symptoms are typically mild in patients with primary RP. Patients with RP secondary to other conditions, most frequently connective tissue disease, are more likely to have severe symptoms, which may be treated with calcium channel blockers, alpha blockers, and vasodilators.
Dr. Caglayan and his team had previously performed an open-label, proof-of-concept study of vardenafil in RP. To confirm those findings, they randomly assigned 53 patients with RP (47 of whom had secondary RP) to receive 10 milligrams of vardenafil twice daily or a placebo for six weeks. After a one-week washout period, patients were switched to the other treatment. Patients were followed for an additional four weeks after the last drug treatment.
Compared to placebo, vardenafil reduced mean Reynaud condition score (RCS) by 0.45 points (p=0.03); the drug cut the number of daily attacks by 0.51 (p=0.005) and their cumulative duration by more than 11 minutes (p=0.003). Digital blood flow improved by 4% (p=0.14) with vardenafil compared to placebo, according to the study, which appeared online June 18 in the Archives of Internal Medicine.
RCS remained lower through the washout, placebo and follow-up phases of the study in patients who began by taking vardenafil, but this effect was not statistically significant.
“This is an interesting unexpected finding in the study,” Dr. Caglayan said. “We observed a persistence of the drug effect after withdrawal for at least 10 weeks, including the follow-up period. This time period would exclude secondary mechanistic effects for this observation on platelet function. We believe that these effects might be explained by some mechanisms which possibly lead to reverse vascular remodeling or de novo angiogenesis.”
Arch Intern Med 2012.