Ambrisentan

Pharmaceuticals -> Listed in ZINC15

Pharmaceuticals -> Antihypertensives

Breast Feeding; Lactation; Milk, Human; Antihypertensive Agents; Cardiovascular Agents; Vasodilator Agents

FDA approved drugs -> Active ingredient

EMA approved medicines: Human medicine

EMA approved medicines: Human medicine

FDA approved drugs -> Active ingredient

Danger

H351 (33.3%): Suspected of causing cancer [Warning Carcinogenicity]

P203, P260, P264, P270, P280, P318, P319, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 3 reports by companies from 3 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Ambrisentan is associated with a low rate of serum aminotransferase elevations (0% to 3%) that in clinical trials was similar to the rate in placebo recipients. These elevations are usually mild (rarely above 3 times ULN), transient and not associated with symptoms. For these reasons, monthly monitoring of serum aminotransferase levels is no longer routinely recommended during ambrisentan therapy.

Drug Induced Liver Injury Rank (DILIrank 2.0)

Ambrisentan

Ambiguous-DILI-concern

7

Adverse reactions

DOI:10.1016/j.drudis.2016.02.015

C02KX02

C - Cardiovascular system

QC - Cardiovascular system

Ambrisentan 10 mg daily had no significant effect on the QTc interval, whereas a 40 mg daily dose of ambrisentan increased mean QTc at tmax by 5 ms with an upper 95% confidence limit of 9 ms. Significant QTc prolongation is not expected in patients taking ambrisentan without concomitant metabolic inhibitors. Plasma concentrations of B-type natriuretic peptide (BNP) in patients who received ambrisentan for 12 weeks were significantly decreased. Two Phase III placebo-controlled studies demonstrated a decrease in BNP plasma concentrations by 29% in the 2.5 mg group, 30% in the 5 mg group, and 45% in the 10 mg group (p < 0.001 for each dose group) and an increase by 11% in the placebo group.

Endothelin-1 (ET-1) is an endogenous peptide that acts on the endothelin type A (ETA) and endothelin type B (ETB) receptors in vascular smooth muscle and endothelium. ETA-mediated actions include vasoconstriction and cell proliferation, whereas ETB predominantly mediates vasodilation, anti-proliferation, and ET-1 clearance. In patients with pulmonary arterial hypertension, ET-1 levels are increased and correlate with increased right arterial pressure and severity of disease. Ambrisentan is one of several newly developed vasodilator drugs that selectively target the endothelin type A (ETA) receptor, inhibiting its action and preventing vasoconstriction. Selective inhibition of the ETA receptor prevents phospholipase C-mediated vasoconstriction and protein kinase C-mediated cell proliferation. Endothelin type B (ETB) receptor function is not significantly inhibited, and nitric oxide and prostacyclin production, cyclic GMP- and cyclic AMP-mediated vasodilation, and endothelin-1 (ET-1) clearance is preserved.

Ambrisentan is a metabolized primarily by uridine 5’-diphosphate glucuronosyltransferases (UGTs) 1A9S, 2B7S,1A3S to form ambrisentan glucuronide. Ambrisentan is also metabolized to a lesser extent by CYP3A4, CYP3A5 and CYP2C19 to form 4- hydroxymethyl ambrisentan which is further glucuronidated to 4-hydroxymethyl ambrisentan glucuronide.

HW6NV07QEC

AMBRISENTAN

Established Pharmacologic Class [EPC] - Endothelin Receptor Antagonist

Mechanisms of Action [MoA] - Endothelin Receptor Antagonists

Ambrisentan is an Endothelin Receptor Antagonist. The mechanism of action of ambrisentan is as an Endothelin Receptor Antagonist.

AMBRISENTAN

Drugs used in the treatment of acute or chronic vascular HYPERTENSION regardless of pharmacological mechanism. Among the antihypertensive agents are DIURETICS; (especially DIURETICS, THIAZIDE); ADRENERGIC BETA-ANTAGONISTS; ADRENERGIC ALPHA-ANTAGONISTS; ANGIOTENSIN-CONVERTING ENZYME INHIBITORS; CALCIUM CHANNEL BLOCKERS; GANGLIONIC BLOCKERS; and VASODILATOR AGENTS.

Ambrisentan is rapidly absorbed with peak plasma concentrations occuring around 2 hours after oral administration. Cmax and AUC increase proportionally with dose across the therapeutic dosing range. Absolute oral bioavailability of ambrisentan is unknown. Absorption is not affected by food.

Ambrisentan is primarily cleared by non-renal pathways. Along with its metabolites, ambrisentan is primarily found in the feces following hepatic and/or extra-hepatic metabolism. Approximately 22% of the administered dose is recovered in the urine following oral administration with 3.3% being unchanged ambrisentan.

Ambrisentan has a low distribution into red blow cells, with a mean blood:plasma ratio of 0.57 and 0.61 in males and females, respectively.

The mean oral clearance of ambrisentan was found to be 38 mL/min in healthy subjects and 19 mL/min in patients with pulmonary artery hypertension.