Bayer HealthCare has reported positive results from a Phase III CHEST-1 trial of its investigational oral soluble guanylate cyclase (sGC) stimulator.
The sGC stimulator, riociguat, 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).
Bayer Healthcare Pharmaceuticals US medical affairs head and vice president Dr Pamela Cyrus said; "There is an unmet medical need for CTEPH patients who are unable to undergo surgery, or who have persistent or recurrent PH after surgery."
The multi-centre, randomised study, which is designed to study the safety and efficacy of the riociguat, is orally treating 261 patients with inoperable CTEPH with either the investigational drug or placebo for 16 weeks.
The study met the primary endpoint showing statistically significant improvement in the six-minute walk distance (6MWD) of 46 metres (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 results are encouraging as the 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 said.
In addition to CTEPH, sGC stimulator is currently under investigation for other types of pulmonary hypertension including pulmonary arterial hypertension.