Macitentan is an orally active endothelin receptor antagonist (ERA) used primarily in the treatment of pulmonary arterial hypertension (PAH). It blocks the effects of endothelin-1, a potent vasoconstrictor involved in vascular smooth-muscle proliferation and remodeling.
Macitentan selectively targets endothelin ETA and ETB receptors and is designed to provide sustained blockade of the endothelin pathway.
Macitentan is a specialized cardiovascular pharmaceutical API used in the development and manufacture of oral formulations for pulmonary arterial hypertension.
Important API quality attributes include identity, assay, related substances, water content, residue on ignition, residual solvents, elemental impurities and polymorphic characteristics.
CAS Number: 441798-33-0
Molecular Formula: C19H20Br2N6O4S
Molecular Weight: 588.28 g/mol
Chemical Name: N-[5-(4-bromophenyl)-6-[2-[(5-bromopyrimidin-2-yl)oxy]ethoxy]pyrimidin-4-yl]-N'-propylsulfamide
Drug Class: Endothelin Receptor Antagonist
Therapeutic Class: Pulmonary Antihypertensive
Therapeutic Area: Cardiovascular / Pulmonology
Molecule Type: Synthetic Small Molecule
Macitentan blocks endothelin receptors, inhibiting the activity of endothelin-1.
Its pharmacological activity includes:
By inhibiting the endothelin pathway, Macitentan helps reduce the excessive vasoconstrictive and proliferative signaling associated with pulmonary arterial hypertension.
Macitentan API is used in pharmaceutical formulations for:
Macitentan is particularly relevant to pulmonary arterial hypertension, where abnormal endothelin signaling contributes to narrowing and remodeling of pulmonary blood vessels.
Its dual endothelin-receptor activity makes it an important pharmaceutical compound for pulmonary vascular disease management and research.
Macitentan is generally described as a white to off-white solid/crystalline powder. Its physicochemical properties should be characterized according to the applicable API specification and formulation requirements.
A controlled Macitentan API manufacturing process may involve:
Typical Macitentan API testing may include:
Store Macitentan API in a tightly closed container under controlled pharmaceutical storage conditions, protected from excessive heat, moisture and direct light. Final storage conditions should follow validated stability data and the manufacturer's approved specification.
Macitentan is relevant to research involving:
| Parameter | Specification |
|---|---|
| Appearance | White to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 1.0% |
| Residue on Ignition | NMT 0.5% |
| Heavy Metals | NMT 10 ppm |
| pH (1% Solution) | 2.0 – 4.0 |
| Individual Impurity | NMT 0.5% |
| Total Impurities | NMT 1.0% |
| Water Content | NMT 1.0% |