SGCB and pulmonary arterial hypertension: Riociguat, a direct, NO-independent sGC stimulator marketed for the treatment of various forms of pulmonary arterial hypertension, also indirectly enhances sGC sensitivity to NO; however, because of considerable interindividual variability in riociguat exposure, a specifically tailored dosage scheme, composed of careful uptitration with three-times-daily (tid) dosing up to the highest tolerated dose for each patient, is needed prior to treatment initiation (Frey et al. 2018).