Macitentan

Macitentan Uses, Dosage, Side Effects, Mechanism of Action, How Long Does it Take to Work? Macitentan is a brand name. Its generic name is Macitentan.

Macitentan Introduction

Macitentan (Opsumit) is an orally administered, selective endothelin receptor antagonist (ERA) developed and marketed by Actelion on behalf of the Japanese pharmaceutical company Takeda. It is used in the treatment of pulmonary arterial hypertension (PAH). Macitentan is a dual inhibitor of endothelin-1 (ET-1) and endothelin-2 (ET-2) receptors, acting on the ETAR to decrease the production and action of ET-1, and on the ETBR to reduce the effect of ET-2. The drug has also been investigated for its potential use in other diseases in which the endothelin system is believed to be involved in pathogenesis, such as congestive heart failure, atherosclerosis, and pre-eclampsia.

Macitentan Uses

Macitentan is indicated for the treatment of pulmonary arterial hypertension (PAH). This includes individuals with WHO Functional Class II-IV symptoms of PAH. Additionally, Macitentan (Opsumit) has been investigated for its potential use in other diseases in which the endothelin system is believed to be involved in pathogenesis, such as congestive heart failure, atherosclerosis, and pre-eclampsia.

Macitentan Mechanism of Action

Macitentan functions as a dual inhibitor of the endothelin-1 (ET-1) and endothelin-2 (ET-2) receptors, acting on the ETAR to decrease the production and action of ET-1, and on the ETBR to reduce the effect of ET-2. The drug also reduces the expression of pro-fibrotic genes, leading to an attenuation of fibrosis in pulmonary arterial endothelium. Macitentane also increases the interactions between pulmonary arterial endothelial cells and smooth muscle cells, leading to an important contribution to the maintenance of the wall of the pulmonary arterial vessels.

How Long does it Take for Macitentan to Work?

The onset of action varies depending on individual patient characteristics. Generally, Macitentan is expected to start working within 1-4 weeks; however, some patients may notice an effect as early as 1 week.

Macitentan Absorption

Macitentan is rapidly absorbed from the gastrointestinal tract, with peak plasma concentrations achieved after 1-2 hours, with a bioavailability of approximately 100%. The drug is highly bound to plasma proteins (approximately 98%).

Macitentan Route of Elimination

The primary route of elimination of Macitentan is through metabolism via CYP2C9 and, to a lesser extent, CYP2C8 and CYP2C19. After metabolism, the drug is mainly eliminated via renal excretion in bile acids and feces.

Macitentan Dosage

The recommended dose of Macitentan is 10 mg once daily. It can be taken with or without food. Unless there is an intolerance or contraindication, Macitentan should be taken at the same time each day.

Macitentan Administration

Macitentan is administered orally, through tablets. It should be taken with a full glass of water. Patients should not chew, divide, or crush the tablets.

Macitentan Side Effects

The most commonly reported side effects of Macitentan include headache, diarrhea, nasopharyngitis, back pain, and an increase in liver enzymes. Other rarer but more serious side effects may include anemia, serious skin reactions, and liver damage.

Macitentan Toxicity

There is a potential for serious toxicity if Macitentan is taken in overdose. Symptoms of toxicity include headache, dizziness, nausea, vomiting, diarrhea, abdominal pain, and hypotension. Treatment of overdose includes symptomatic and supportive care as needed.

Macitentan Precaution

Patients should be monitored closely for liver function, blood pressure, and symptoms of toxicity. Macitentan should not be used in combination with other endothelin receptor antagonists or in patients with known hypersensitivity to the drug.

Macitentan Interaction

Macitentan may interact with strong CYP2C8 and CYP2C9 inducers or inhibitors, as well as drugs that are known to prolong the QT interval. Macitentan should be used with caution in patients taking other drugs that may have similar effects.

Macitentan Disease Interactions

Macitentan is contraindicated in patients with severe hepatic impairment. Use with caution in patients with mild-to-moderate hepatic impairment and in those with a history of hepatic impairment. Use should be avoided in patients with moderate-to-severe renal impairment.

Macitentan Drug Interactions

Macitentan may interact with strong CYP2C8 and CYP2C9 inducers or inhibitors, as well as drugs that are known to prolong the QT interval. Macitentan should be used with caution in patients taking other drugs that may have similar effects.

Macitentan Food Interactions

Macitentan should not be taken with food that is high in fat as this may decrease the absorption of Macitentan. Grapefruit juice should be avoided as this may increase the amount of Macitentan that is absorbed in the body.

Macitentan Pregnancy Use

Macitentan is not recommended for use in pregnant women. There is no data on the use of Macitentan in pregnant animals. Animal studies have shown reproductive toxicity.

Macitentan Lactation Use

Neither Macitentan nor any of its metabolites have been detected in human milk. However, a clinical decision should be made about whether to discontinue breastfeeding based on the importance of the drug to the mother.

Macitentan Acute Overdose

In the event of an acute overdose of Macitentan, the patient should be monitored for signs and symptoms of toxicity and supportive care should be given as needed.

Macitentan Contraindication

Macitentan is contraindicated in patients with severe hepatic impairment and in those with known hypersensitivity to the drug. It should also be used with caution in patients with mild-to-moderate hepatic impairment and in those taking other drugs that may have similar effects.

Macitentan Use Direction

The recommended dose of Macitentan is 10 mg once daily. It can be taken with or without food. Unless there is an intolerance or contraindication, Macitentan should be taken at the same time each day.

Macitentan Storage Condition

Macitentan should be stored at room temperature away from light and moisture. Do not store it in the bathroom. Keep the container tightly closed when not in use.

Macitentan Volume of Distribution

The volume of distribution of Macitentan is 4.6 L/kg.

Macitentan Half-Life

The half-life of Macitentan is approximately 7.2 hours.

Macitentan Clearance

The clearance of Macitentan is 1.3 L/h/kg.

Here you find in details version of Macitentan

Some Frequently Asked Questions About Macitentan