CALCA and systemic sclerosis: However, secondary RP frequently leads to vasculopathic damage, including ulceration and infarction.11 Approximately 50% of patients with systemic sclerosis will experience digital ulceration at some point in the disease course.12 In the patient cohorts in this study, the duration of RP before CGRP antagonist exposure was not correlated with progression to complications because approximately half of the patients with complications (4 of 9 patients) were newly diagnosed with RP after CGRP exposure.