Randomized Placebo-Controlled Crossover Trial of Tadalafil in Raynaud’s Phenomenon Secondary to Systemic Sclerosis

Abstract

Raynaud's phenomenon (RP) is an important clinical feature of systemic sclerosis (SSc) for which consistently effective therapies are lacking. The study was designed to assess the safety, tolerability, and efficacy of tadalafil, a selective, long acting type V cyclic GMP phosphodiesterase (PDE-5) inhibitor, in this clinical syndrome. We performed a prospective, randomized, double-blind, placebo-controlled, crossover study comparing oral tadalafil at a fixed dose of 20 mg daily for a period of 4 weeks versus placebo in women with RP secondary to SSc. Thirty-nine subjects completed the study and were evaluable. There were no statistically significant differences in Raynaud Condition Score (RCS), frequency of RP episodes, or duration of RP episodes between treatment groups. Placebo response was a confounding factor. Tadalafil was well tolerated. Tadalafil appears to be safe and well tolerated but lacks efficacy in comparison to placebo as a treatment for RP secondary to SSc.