Treprostinil

Pharmaceuticals -> Antihypertensives

Pharmaceuticals -> Listed in ZINC15

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

FDA approved drugs -> Active ingredient

EMA approved medicines: Human medicine (Orphan designations)

FDA approved drugs -> Active ingredient

Danger

H301 (100%): Toxic if swallowed [Danger Acute toxicity, oral]

P203, P260, P261, P262, P264, P264+P265, P270, P271, P280, P301+P316, P302+P352, P304+P340, P305+P351+P338, P316, P318, P319, P321, P330, P332+P317, P337+P317, P361+P364, P362+P364, P403+P233, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 2 reports by companies from 2 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Researchers did encounter treprostinil overdose during the trials, which presented with signs and symptoms of vasodilatation such as flushing, hypotension, and headache. It can also result from pump dysfunction, accidental bolus administration, or prescribing the wrong dose. These symptoms are self-limited and will be resolved by temporarily discontinuing the medication or reducing the dosage.

B - Blood and blood forming organs

QB - Blood and blood forming organs

As an analogue of prostacyclin, treprostinil promotes the vasodilation of pulmonary and systemic arterial vascular beds and the inhibition of platelet aggregation. In animals, the vasodilatory effects of treprostinil lead to a reduction of right and left ventricular afterload and an increase in cardiac output and stroke volume. Treprostinil also causes a dose-related negative inotropic and lusitropic effect, and no major effects on cardiac conduction have been detected. Short-lasting effects on QTc were detected in healthy volunteers (n=240) given inhaled single doses of 54 and 84 μg of treprostinil. These effects dissipated rapidly as treprostinil concentrations lowered. When given subcutaneously or intravenously, treprostinil has the potential to reach higher concentrations. The effect of oral treprostinil on QTc has not been evaluated. Due to its ability to inhibit platelet aggregation, treprostinil can increase the risk of bleeding, and patients with low systemic arterial pressure taking treprostinil may experience symptomatic hypotension. The abrupt withdrawal of treprostinil or drastic changes in dose may worsen the symptoms of pulmonary arterial hypertension (PAH). The inhalation of treprostinil can also cause bronchospasms in patients with asthma, chronic obstructive pulmonary disease (COPD), or bronchial hyperreactivity. When given intravenously, treprostinil can lead to infusion complications and increase the risk of bloodstream infections.

Treprostinil is a stable analogue of prostacyclin, a prostaglandin that acts as an anti-thrombotic agent and a potent vasodilator. Prostacyclin analogues are useful in the treatment of pulmonary arterial hypertension (PAH), a disease characterized by abnormally high blood pressure in the arteries between the heart and lungs. PAH leads to right heart failure due to the remodelling of pulmonary arteries, and patients with this condition have a poor prognosis. Treprostinil binds and activates the prostacyclin receptor, the prostaglandin D2 receptor 1, and the prostaglandin E2 receptor 2. The activation of these receptors leads to the elevation of intracellular cyclic adenosine monophosphate (cAMP) levels, which consequently promotes the opening of calcium-activated potassium channels that lead to cell hyperpolarization. This mechanism promotes the direct vasodilation of pulmonary and systemic arterial vascular beds and the inhibition of platelet aggregation. In addition to its direct vasodilatory effects, treprostinil inhibits inflammatory pathways.

Treprostinil is mostly metabolized by the liver, mainly by CYP2C8, and by CYP2C9 to a lesser extent. Treprostinil does not have a single major metabolite. The five metabolites detected in urine (HU1 through HU5) accounted for 13.8, 14.3, 15.5, 10.6 and 10.2% of the dose, respectively. One of the metabolites (HU5) is the glucuronide conjugate of treprostinil. HU1, HU2, HU3 and HU4 are formed through the oxidation of the 3-hydroxyloctyl side chain. None of the metabolites of treprostinil appear to be active. _In vitro_ studies suggest that treprostinil does not inhibit or induce any major CYP enzymes.

RUM6K67ESG

TREPROSTINIL

Established Pharmacologic Class [EPC] - Prostacycline Vasodilator

Chemical Structure [CS] - Prostaglandins I

Physiologic Effects [PE] - Vasodilation

Treprostinil is a Prostacycline Vasodilator. The physiologic effect of treprostinil is by means of Vasodilation.

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.

After subcutaneous infusion, treprostinil is completely absorbed, with a bioavailability of about 100%, and it reaches steady-state concentrations in approximately 10 hours. The pharmacokinetics of treprostinil follow a two-compartment model and are linear between 2.5 and 125 ng/kg/min. Subcutaneous and intravenous doses of treprostinil are bioequivalent at 10 ng/kg/min. Compared to healthy subjects, patients with mild and moderate hepatic insufficiency had a corresponding Cmax 2- and 4-times higher and an AUC0-∞ 3- and 5-times higher when given a subcutaneous treprostinil dose of 10 ng/kg/min for 150 min. When given orally at doses between 0.5 and 15 mg twice a day, treprostinil follows a dose-proportional pharmacokinetic profile. The oral bioavailability of treprostinil is 17%, and drug concentration reaches its highest level between 4 and 6 hours after oral administration. The oral absorption of treprostinil is affected by food. The AUC and Cmax of oral treprostinil increase 49% and 13%, respectively, when this drug is administered with a high-fat, high-calorie meal. The AUC and Cmax of inhaled treprostinil were proportional to the doses administered (18 to 90 μg). The bioavailability of inhaled treprostinil was 64% in patients receiving 2 doses of 18 μg, and 72% in patients receiving two doses of 36 μg. Two separate studies that evaluated the pharmacokinetics of inhaled treprostinil at a maintenance dose of 54 μg found that the mean Cmax was 0.91 and 1.32 ng/mL, respectively, with a corresponding Tmax of 0.25 and 0.12 hr and a mean AUC of 0.81 and 0.97 hr⋅ng/mL.

Treprostinil metabolites are excreted through urine (79%) and feces (13%) over 10 days. Only a small proportion of treprostinil is excreted unchanged. When administered orally, 1.13% and 0.19% of unchanged treprostinil diolamine are found in urine and feces, respectively. When administered subcutaneously, intravenously or by inhalation, 4% of unchanged treprostinil is found in urine.

The volume of distribution of treprostinil is 14 L/70 kg.

The clearance of treprostinil is 30 L/hr in a 70 kg person. In patients with mild to moderate hepatic insufficiency, clearance is reduced up to 80%.