Macitentan is the most recently approved dual endothelin-receptor antagonist (ERA) for the treatment of symptomatic pulmonary arterial hypertension. Compared to other available ERAs, it demonstrates superior receptor-binding properties, with consequently improved tissue penetration, and a longer duration of action allowing for once-daily dosing. It has a favorable adverse-effect profile, with notably no demonstrable increase in the risk of hepatotoxicity or peripheral edema, but like other ERAs, it is potentially limited by significant anemia. Phase I data have demonstrated a favorable drug-drug interaction profile and no need for dose adjustment with hepatic and renal impairment. In the pivotal SERAPHIN study, treatment of symptomatic pulmonary arterial hypertension patients with macitentan led to statistically significant improvements in functional class, exercise tolerance, and hemodynamic parameters, in addition to a reduction in morbidity in an event-driven long-term trial.
Keywords: endothelin; endothelin receptor antagonists; macitentan; pulmonary arterial hypertension.