Efficacy of ORM-12741 for Prevention of Raynaud's Phenomenon

Inclusion Criteria: * Written informed consent obtained * Age of 10-75 years (inclusive) * Body mass index (BMI) between 10-30 kg/m2 (inclusive) * Male or female patients with a diagnosis of active Raynaud's phenomenon (RP) secondary to systemic sclerosis. Active RP will be defined as a history of cold sensitivity associated with colour changes of cyanosis or pallor, as well as of at least 6 attacks weekly during the winter months. Diagnosis of systemic sclerosis will be defined by the European League Against Rheumatism (EULAR) criteria. * Stable symptoms for RP and medication requirements within 2 months prior to screening * Negative pregnancy test for females of childbearing potential Exclusion Criteria: * Treatment with nitrates * Treatment with calcium channel blockers (CCBs)for indications other than the relief of RP symptoms * Treatment with calcium channel blockers (CCBs) for the relief of RP symptoms that in the opinion of the investigator cannot be stopped from the screening visit until end of the last experimental session * Changes in dosing of other vasoactive medications within 1 month prior to screening or during the study * Smoking or smoking cessation using nicotine products within 3 months prior to screening * Current active ischemic digital ulcer and/or tissue gangrene * History of sympathectomy * Upper extremity deep vein thrombosis or lymphoedema within 3 months prior to screening. * Clinically significant cardiovascular, pulmonary, gastrointestinal, hep…