Oral Ifetroban to Treat Diffuse Cutaneous Systemic Sclerosis (SSc) or SSc-associated Pulmonary Arterial Hypertension

Inclusion Criteria: Diffuse Cutaneous Criterion: 1\. Systematic Sclerosis (SSc), as defined using the 2013 American College of Rheumatology/ European Union League Against Rheumatism Classification Criteria and dcSSc within 7 years following initial diagnosis as defined by the onset of the first non-Raynaud symptom. SSc-PAH Criteria: 1. Adults fulfilling the 2013 American College of Rheumatology/ European Union League Against Rheumatism Classification Criteria with confirmed SSc-PAH (limited or dcSSc) confirmed via previous cardiac catheterization 2. Stable oral therapy for PAH for at least 30 days (monotherapy or combination) 3. New York Heart Association (NYHA) Class I-III Heart Failure Exclusion Criteria: 1. Have a diagnosis of systemic sclerosis sine scleroderma; 2. Be less than 18 years of age or greater than or equal to 80 years of age; 3. Be pregnant, nursing, or planning to become pregnant; 4. Current or planned treatment with prostanoid therapy; 5. Current or planned treatment with pirfenidone; 6. Use of rituximab in the last 3 months; 7. Use of mycophenolic acid (Myfortic, CellCept) at a stable dose for less than 3 months; 8. Current or planned corticosteroid therapy greater than 15mg per day of prednisone or prednisone equivalent; 9. Significant lung disease, defined as FVC \< 50% predicted or DLCO \<40% predicted; 10. Significant kidney disease, defined as Glomerular Filtration Rate (GFR) \< 60 ml/min; 11. Have moderate or severe hepatic impairment; 12. Contraindication to MRI (e.g., implanted magnetic material, claustrophobia); 13. Known hypersensitivity to gadolinium; 14. Any cause of pulmonary hypertension other than World Health Organization (WHO) Group I associated with SSc; 15. Use of aspirin \> 81 mg per day in the last two weeks; 16. Use of warfarin, heparin or other anticoagulants in the last 30 days; 17. Recent (within 6 weeks) myocardial infarction or persistent atrial arrhythmias; 18. Have a history of allergy or hypersensitivity to ifetroban; 19. Have taken investigational drugs within 30 days before study treatment administration; 20. Inability to understand the requirements of the study, inability to understand spoken English and abide by the study restrictions and to return for the required treatments and assessments; 21. Be otherwise unsuitable for the study, in the opinion of the investigator.