Riociguat rEplacing PDE-5i Therapy evaLuated Against Continued PDE-5i thErapy

Data from a previous single arm study (RESPITE) indicate that transition from PDE5i to riociguat may be feasible, safe and beneficial in patients not adequately responding to PDE5i. REPLACE is a randomized controlled study to confirm the potential clinical benefit of transition from PDE5i to riociguat. Satisfactory clinical response in patients who are on a stable dose of phosphodiesterase-5inhibitors (PDE-5i) with or without endothelin receptor antagonist (ERA), but not at treatment goal will be compared between one group of patients randomized to maintain current treatment and another group where the PDE5i is replaced by riociguat.