The drug is a oral soluble guanylate cyclase (sGC) stimulator which is designed to treat patients with either inoperable chronic thromboembolic pulmonary hypertension (CTEPH) or pulmonary hypertension (PH) which has persisted or reoccurred after pulmonary endarterectomy (PEA).
The multi-center, randomized study, which has enrolled 261 patients with inoperable CTEPH, has treated patients with either investigational drug or placebo orally for 16 weeks to study the safety and efficacy of the investigational drug.
Th study met the primary endpoint showing statistically significant improvement in the six-minute walk distance (6MWD) of 46 meters (95%-CI [25-67 meters] p<0.0001).
The study also demonstrated significant improvements in secondary endpoints including pulmonary vascular resistance (PVR) (p<0.0001), N-terminal prohormone brain natriuretic peptide (NT-proBNP) (p<0.0001) and WHO functional class (FC) (p=0.0026).
University Hospital Giessen lead investigator professor Hossein Ardeschir Ghofrani said the study results with investigational riociguat are encouraging in which a drug treatment has demonstrated significant improvement in 6MWD in patients with inoperable CTEPH or with PH after surgery.
"Results from the Phase III development program suggest that riociguat may be a potential new option in CTEPH," Ghofrani added.
The company said in addition to CTEPH, sGC stimulator is currently under investigation for pulmonary arterial hypertension.