What is Riociguat?
Riociguat is a Bayer-manufactured drug that acts as a stimulant of soluble guanylate cyclase. It is used to treat two types of pulmonary hypertension: chronic thromboembolic and pulmonary arterial hypertension. Riociguat is the first member of the sGC stimulator class of drugs.
Riociguat uses
Riociguat is used to treat adults who have chronic thromboembolic pulmonary hypertension (CTEPH) and cannot be treated surgically.
How does Riociguat work?
Riociguat is a stimulator of soluble guanylate cyclase (sGC), a cardiopulmonary enzyme and nitric oxide receptor. When NO binds to sGC, the enzyme catalyzes the synthesis of cyclic guanosine monophosphate, a signaling molecule.
Dosage
Dosage is adjusted according to the patient’s response and tolerance: For the first two weeks, 0.5-1 mg tid, approximately 6-8 hours apart. Increase dose in 1.5 mg daily increments over a two-week period up to a maximum of 2.5 mg tid if systolic blood pressure is less than 95 mmHg and there is no hypotension. If hypotension occurs, reduce the dose by 0.5 mg tid. If treatment is interrupted for more than three days, reduce the retitrate dose from the initial dose.
Administration
Riociguat is administered using an 8-week individual dose-adjustment scheme whereby a patient initially receives riociguat 1.0 mg three times daily (tid), and the dose is then increased every 2 weeks in the absence of hypotension, indicated by systolic blood pressure measurements and symptoms, up to a maximum dose of 2.5 mg tid.
Riociguat side effects
Riociguat may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- Headache
- Constipation
- Heartburn
- Upset stomach
- Nausea
- Vomiting
- Diarrhea
- Swelling of your hands, legs, feet, and ankles
Riociguat drug interaction
Some products that may interact with this drug include: aminophylline, certain drugs used to treat chest pain/angina or high blood pressure (nitrates such as nitroglycerin, isosorbide), dipyridamole, drugs to treat erectile dysfunction-ED/pulmonary hypertension (such as sildenafil, tadalafil, vardenafil)
Precautions/ safety information
Do not use this medicine together with dipyridamole, theophylline, or medicine for impotence (eg, sildenafil, tadalafil, vardenafil) (eg, sildenafil, tadalafil, vardenafil). Using these medicines together may cause hypotension (low blood pressure) (low blood pressure). This medicine could lower your blood pressure and cause you to feel dizzy or lightheaded.
Storage
Store at 25°C.
Contraindications
Riociguat has the potential to harm a developing fetus and is therefore contraindicated in pregnant women. Additionally, the drug is contraindicated in patients with pulmonary hypertension who simultaneously have idiopathic interstitial pneumonia (PH-IIP). A clinical trial assessing riociguat for this purpose was prematurely discontinued due to the drug’s increased risk of severe side events and mortality in patients with pulmonary hypertension caused by idiopathic interstitial pneumonia when compared to placebo.
Pregnancy or lactation
There are insufficient studies in women to determine the risk to infants when this medication is used during breastfeeding. Before taking this medication while breastfeeding, weigh the potential benefits and risks.
