Effects of bosentan on nondigital ulcers in patients with systemic sclerosis

Summary Background Bosentan is an oral dual endothelin receptor antagonist, which has been shown to be efficacious for preventing new digital ulcers in patients with systemic sclerosis (SSc) in two high-quality randomized controlled trials. However, its efficacy for nondigital ulcers in SSc remains unknown. Objectives To evaluate the efficacy of bosentan on nondigital ulcers in patients with SSc. Methods Bosentan was administered to five patients with SSc with pulmonary arterial hypertension, who also had nondigital ulcers refractory to conventional treatments. The efficacy of bosentan on nondigital ulcers and its association with clinical features of ulcers were analysed. Results The nondigital ulcers refractory to conventional treatments were significantly improved by the administration of bosentan in cases surrounded with severe cyanosis. In contrast, nondigital ulcers without cyanosis were still refractory to bosentan therapy. Conclusions Bosentan may be efficacious for accelerating the healing of nondigital ulcers with severe cyanosis, suggesting that nondigital ulcers caused by severely impaired peripheral circulation are highly responsive to this treatment.