Generic
Macitentan
1 brands available in the market
At a glance
Macitentan is used for the long-term treatment of pulmonary arterial hypertension (PAH). It acts as an endothelin receptor antagonist to reduce vasoconstriction and inflammation.
Description
Macitentan is an endothelin receptor antagonist that inhibits the binding of ET-1 to both ETA and ETB receptors. It displays high affinity and sustained occupancy of ET receptors in human pulmonary arterial smooth muscle cells. One of its metabolites is also pharmacologically active.
Indications
- Pulmonary arterial hypertension (PAH) - WHO functional class II to III (idiopathic, heritable, connective tissue disease-associated, congenital heart disease-associated)
Therapeutic class
Anti-hypertensive
Pharmacological class
Endothelin Receptor Antagonist
Pharmacology
Macitentan blocks ETA and ETB receptors to inhibit ET-1-mediated vasoconstriction, fibrosis, proliferation, hypertrophy, and inflammation.
Mechanism of action
Reduces pulmonary artery pressure by blocking endothelin receptors.
Dosage
Adult Dose (Oral): 10 mg once daily
Administration
- Swallow tablets whole with water
- May be taken with or without food
- Take at about the same time each day
Missed dose
If a dose is missed, take it as soon as possible and then take the next dose at the regularly scheduled time. Do not take two doses at the same time.
Side effects
Common Side Effects:
- Nasopharyngitis (14%)
- Headache (13.6%)
- Anemia (13.2%)
Precautions & warnings
- Obtain liver enzyme tests prior to initiation
- Not recommended in patients with severe anemia
- Avoid concomitant use with strong CYP3A4 inducers
- Caution with strong CYP3A4 inhibitors
- Contraindicated in pregnancy and lactation
Contraindications
- Hypersensitivity
- Pregnancy and lactation
- Severe hepatic impairment
Drug interactions
- Strong CYP3A4 inducers (rifampin) significantly reduce macitentan exposure
- Strong CYP3A4 inhibitors (ketoconazole, ritonavir) approximately double macitentan exposure
Food interactions
Avoid concomitant use with strong CYP3A4 inducers.
Use in pregnancy
Use in Pregnancy: Contraindicated during pregnancy. Verify absence of pregnancy in women of childbearing potential before initiation; monthly pregnancy tests recommended.
Pregnancy Category: X — always consult a doctor before taking during pregnancy.
Use in lactation
Use in Lactation: Contraindicated during breastfeeding (unknown if excreted in human milk).
Pediatric use
Safety not established in children and adolescents below 18 years.
Geriatric use
Limited clinical data in patients over 75 years; use with caution.
Renal / hepatic impairment
Renal Impairment: No dose adjustment required; caution in severe renal impairment or dialysis.
Hepatic Impairment: Do not initiate in severe hepatic impairment; monitor liver enzymes.
Overdose effects
Overdose may cause headache, nausea, and vomiting; dialysis is unlikely to be effective due to high protein binding.
Storage conditions
Store below 30°C, away from light and moisture; keep out of reach of children.
Chemical structure
Macitentan