Last reviewed 2026-04-22 · How we verify

Riociguat (Adempas)

Riociguat is a soluble guanylate cyclase stimulator that directly activates the enzyme to increase cyclic GMP levels, promoting vasodilation and reducing pulmonary vascular resistance.

Riociguat is a soluble guanylate cyclase stimulator that directly activates the enzyme to increase cyclic GMP levels, promoting vasodilation and reducing pulmonary vascular resistance. Used for Pulmonary hypertension (chronic thromboembolic pulmonary hypertension, CTEPH), Pulmonary hypertension (WHO Group 1, pulmonary arterial hypertension).

At a glance

Mechanism of action

Riociguat binds to and activates soluble guanylate cyclase (sGC) independent of nitric oxide availability, increasing intracellular cyclic GMP (cGMP) concentrations. This leads to smooth muscle relaxation in pulmonary and systemic vasculature, reducing pulmonary vascular resistance and improving hemodynamics in pulmonary hypertension. Unlike phosphodiesterase-5 inhibitors that prevent cGMP breakdown, riociguat directly stimulates cGMP production, making it effective even in conditions with impaired nitric oxide signaling.

Approved indications

• Pulmonary hypertension (chronic thromboembolic pulmonary hypertension, CTEPH)
• Pulmonary hypertension (WHO Group 1, pulmonary arterial hypertension)

Common side effects

• Hypotension
• Headache
• Dyspepsia
• Dizziness
• Syncope

Key clinical trials

• Riociguat in Children With Pulmonary Arterial Hypertension (PAH) (PHASE3)
• Treatment of Exercise-Induced Pulmonary Vascular Dysfunction After Pulmonary Thromboendarterectomy or Balloon Pulmonary Angioplasty (PHASE2)
• Riociguat in Triple Therapy for Pulmonary Arterial Hypertension in Real-World Practice
• Efficacy and Safety of Riociguat in Incipient Pulmonary Vascular Disease as an Indicator for Early PAH (PHASE2)
• A Study of Sotatercept for Patients With Eisenmenger Syndrome or Unrepaired Shunt-Associated Pulmonary Arterial Hypertension Resistant to Vasodilator Therapy (PHASE4)
• Effects of Combination Medical Therapy Followed by BPA on Right Ventricular-PA Coupling and Hemodynamics in CTEPH (PHASE3)
• A Long-term Extension Study of Riociguat in Patients With Symptomatic Pulmonary Arterial Hypertension. (PHASE4)
• Effects of Riociguat on RIght VEntricular Size and Function in PAH and CTEPH (PHASE4)

Primary sources

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