Successful treatment of patients with severe secondary Raynaud's phenomenon with the endothelin receptor antagonist bosentan

Abstract

Secondary Raynaud's phenomenon (RP) in patients with systemic sclerosis (SSc) and other collagen vascular diseases is a serious manifestation of microvascular damage that may precede the onset of visceral and/or cutaneous sclerosis for years. Recent studies have demonstrated that the endothelin receptor antagonist bosentan prevents the development of new digital ulcers in SSc. We investigated the potential benefits of bosentan in patients with secondary RP associated with pre-scleroderma and with SSc, independent of digital ulcers. Three patients with secondary RP received bosentan 62.5 mg twice daily for 4 weeks followed by 125 mg twice daily for 12 weeks during the winter season. Pain (visual analogue scale), Raynaud's disease activity (Scleroderma Health Assessment Questionnaire), number and severity of daily Raynaud's attacks (diary) and peripheral thermoregulation (thermography) were assessed during treatment periods. Pain, Raynaud's disease activity, number and severity of Raynaud's attacks significantly decreased during treatment periods. Thermography after 16-week treatment demonstrated improved peripheral thermoregulation. Although this is a small observational study, treatment with bosentan appears to measurably reduce the daily impact of Raynaud's disease and improve peripheral thermoregulation in patients with secondary RP, independent of digital ulcers.