Comparative Pharmacology
Head-to-head clinical analysis: FILSPARI versus LETAIRIS.
Peer-Reviewed Evidence
Head-to-head clinical analysis: FILSPARI versus LETAIRIS.
FILSPARI vs LETAIRIS
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
FILSPARI (sparsentan) is an endothelin receptor antagonist (ERA) and angiotensin II receptor blocker (ARB) with high affinity for the endothelin type A (ETA) receptor and angiotensin II type 1 (AT1) receptor. It reduces proteinuria in IgA nephropathy by inhibiting endothelin-1 mediated vasoconstriction, inflammation, and fibrosis, and by blocking angiotensin II mediated effects.
Ambrisentan is an endothelin receptor antagonist that selectively inhibits endothelin-1 (ET-1) binding to endothelin type A (ETA) receptors in pulmonary vascular smooth muscle cells, reducing vasoconstriction and smooth muscle proliferation.
200 mg orally once daily, with or without food.
5 mg orally once daily, with or without food; may increase to 10 mg once daily if tolerated.
None Documented
None Documented
Terminal half-life ~30 hours in healthy subjects, supporting once-daily dosing.
Terminal elimination half-life is approximately 9 hours (range 6–12 hours) in healthy adults.
Primarily hepatic metabolism; <1% excreted unchanged in urine. ~59% of dose recovered in feces and ~27% in urine as metabolites.
Primarily via biliary/fecal elimination (approximately 80% of metabolites and unchanged drug; ~20% renal as metabolites).
Category C
Category C
Endothelin Receptor Antagonist / ARB
Endothelin Receptor Antagonist