Sitaxentan (Sitaxsentan) is a potent and selective endothelin ET(A) receptor antagonist once used in the treatment of pulmonary arterial hypertension (PAH), but removed from the market because of hepatotoxicity. It is over 6000-fold selective for the the ETA receptor subtype with an IC50 of 1 nM for ETA versus an IC50 of 9800 nM for ETB.
Sitaxsentan prevents shunt mediated elevation of pulmonary vascular resistance (PVR).
[1] Sitaxsentan effectively inhibits basolateral Na
+-taurocholate cotransporting polypeptide (NTCP), organic anion-transporting polypeptides (OATPs) and bile salt export pump (BSEP).
[2]