The safety and effectiveness of riociguat to treat chronic thromboembolic pulmonary hypertension.

Chronic thromboembolic pulmonary hypertension (CTEPH) is an insidious, progressive disease with a poor prognosis. The treatment of choice is pulmonary thromboendarterectomy, although not all patients benefit from surgery at a specialized center. Riociguat, an oral soluble guanylate cyclase (sGC) stimulator is the first pharmacotherapeutic agent that has been shown to improve exercise capacity and hemodynamics in a large multicenter, double-blind, randomized placebo-controlled trial for the treatment of patients with inoperable or persistent CTEPH. Riociguat stimulates sGC directly in a nitric oxide (NO)-independent manner, thereby increasing the sensitivity of sGC to NO, and also in synergy with NO, leading to increased production of cyclic guanosine monophosphate, an intracellular messenger involved in regulating vascular tone, smooth muscle cell proliferation, fibrosis and inflammation. This review will summarize the pharmacodynamics, pharmacokinetics as well as safety and efficacy data of riociguat in inoperable or persistent CTEPH.