Volibris: Uses, Dosage & Side Effects

A selective endothelin receptor antagonist (ERA) for the treatment of pulmonary arterial hypertension (PAH) in adults, adolescents, and children from 8 years of age

Rx ATC: C02KX02 Endothelin Receptor Antagonist
Active Ingredient
Ambrisentan
Available Forms
Film-coated tablets
Strengths
2.5 mg, 5 mg, 10 mg
Manufacturer
GlaxoSmithKline (GSK)

Volibris (ambrisentan) is a selective endothelin type A (ETA) receptor antagonist used to treat pulmonary arterial hypertension (PAH). PAH is a serious progressive condition characterized by abnormally high blood pressure in the pulmonary arteries, leading to right heart failure if untreated. Volibris works by blocking the effects of endothelin-1, a powerful vasoconstrictor, thereby widening the pulmonary arteries, reducing pulmonary vascular resistance, and improving exercise capacity and symptoms. It is approved for adults, adolescents, and children aged 8 years and older, and can be used alone or in combination with other PAH therapies such as PDE5 inhibitors. Volibris is taken as a once-daily oral tablet and requires a prescription from a specialist physician.

Quick Facts: Volibris

Active Ingredient
Ambrisentan
Drug Class
Endothelin Receptor Antagonist
ATC Code
C02KX02
Common Uses
Pulmonary Arterial Hypertension
Available Forms
Oral Tablet
Prescription Status
Rx Only

Key Takeaways

  • Volibris (ambrisentan) is a selective endothelin receptor antagonist that widens pulmonary arteries and reduces the workload on the heart in patients with pulmonary arterial hypertension (PAH).
  • It is approved for use in adults and children from 8 years of age, with dosing based on body weight in pediatric patients. The standard adult starting dose is 5 mg once daily, which may be increased to 10 mg.
  • Volibris must not be taken during pregnancy due to a high risk of birth defects; reliable contraception and regular pregnancy testing are mandatory for women of childbearing potential.
  • The AMBITION trial demonstrated that initial combination therapy with ambrisentan and tadalafil significantly reduces the risk of clinical failure compared with monotherapy, making combination treatment the current standard of care for many PAH patients.
  • Regular blood tests are required to monitor for anemia (low red blood cell counts) and liver function throughout treatment. Common side effects include peripheral edema, headache, nasal congestion, and palpitations.

What Is Volibris and What Is It Used For?

Quick Answer: Volibris (ambrisentan) is a medication used to treat pulmonary arterial hypertension (PAH). It belongs to a class of drugs called endothelin receptor antagonists, which work by blocking the effects of endothelin-1 to widen the blood vessels in the lungs, reduce blood pressure in the pulmonary arteries, and improve exercise capacity and symptoms.

Volibris contains the active substance ambrisentan, which belongs to a group of medications known as endothelin receptor antagonists (ERAs). Endothelin-1 (ET-1) is one of the most potent naturally occurring vasoconstrictors in the human body. In patients with pulmonary arterial hypertension, endothelin-1 levels are significantly elevated, and this peptide plays a central pathological role by causing sustained vasoconstriction and promoting the abnormal proliferation of smooth muscle cells within the walls of the pulmonary arteries. Over time, these processes lead to progressive narrowing and remodeling of the pulmonary vasculature, increasing pulmonary vascular resistance and placing an enormous strain on the right ventricle of the heart.

Ambrisentan is a selective antagonist of the endothelin type A (ETA) receptor. The ETA receptor is predominantly expressed on vascular smooth muscle cells and mediates the vasoconstrictive and proliferative effects of endothelin-1. By selectively blocking the ETA receptor, ambrisentan inhibits ET-1–mediated vasoconstriction and reduces smooth muscle cell proliferation in the pulmonary arteries. This selectivity distinguishes ambrisentan from dual (ETA/ETB) endothelin receptor antagonists such as bosentan. The ETB receptor, found primarily on endothelial cells, mediates vasodilation through the release of nitric oxide and prostacyclin, as well as endothelin-1 clearance. By preserving ETB receptor signaling, ambrisentan theoretically maintains these beneficial endothelial functions while blocking the harmful effects mediated through the ETA receptor.

Pulmonary arterial hypertension (PAH) is a progressive and life-threatening condition in which the mean pulmonary artery pressure is chronically elevated. The World Health Organization (WHO) classifies pulmonary hypertension into five groups, with PAH designated as Group 1. PAH can be idiopathic (of unknown cause), heritable (genetic), or associated with conditions such as connective tissue diseases (particularly systemic sclerosis), congenital heart disease, portal hypertension, HIV infection, or drug/toxin exposure. Regardless of the underlying cause, the hallmark of PAH is progressive vascular remodeling of the small pulmonary arteries, leading to increased pulmonary vascular resistance, right ventricular failure, and ultimately death if untreated.

The clinical efficacy of ambrisentan in PAH has been established in the pivotal ARIES-1 and ARIES-2 randomized controlled trials. These double-blind, placebo-controlled studies enrolled patients with idiopathic PAH or PAH associated with connective tissue disease, and demonstrated statistically significant improvements in six-minute walk distance (6MWD), WHO functional class, and time to clinical worsening compared with placebo. The ARIES-E extension study further confirmed that the clinical benefits of ambrisentan are sustained over long-term treatment, with improvements in exercise capacity maintained for at least two years.

Perhaps the most impactful evidence supporting the use of ambrisentan in modern PAH management comes from the landmark AMBITION trial. This large, multicenter, randomized controlled trial compared initial combination therapy with ambrisentan plus tadalafil against monotherapy with either drug alone in treatment-naive PAH patients. The results were striking: initial combination therapy reduced the risk of clinical failure events (a composite of death, hospitalization for worsening PAH, disease progression, or unsatisfactory long-term clinical response) by 50% compared with pooled monotherapy. This trial fundamentally changed PAH treatment paradigms and established upfront combination therapy as the standard of care according to the 2022 ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension.

Combination Therapy Standard

Current ESC/ERS guidelines recommend initial combination therapy with an ERA (such as ambrisentan) and a PDE5 inhibitor (such as tadalafil) for most newly diagnosed PAH patients with intermediate or high risk profiles. This approach targets two distinct pathological pathways simultaneously – the endothelin pathway and the nitric oxide pathway – providing superior outcomes compared with sequential monotherapy.

What Should You Know Before Taking Volibris?

Quick Answer: Do not take Volibris if you are pregnant, allergic to ambrisentan or soy, have severe liver disease, or have idiopathic pulmonary fibrosis. Women of childbearing potential must use reliable contraception and undergo regular pregnancy testing. Regular blood tests for anemia and liver function are required throughout treatment.

Contraindications

There are specific situations in which Volibris must not be used. Understanding these absolute contraindications is essential before starting treatment.

  • Pregnancy: Volibris must not be taken during pregnancy. Ambrisentan is teratogenic (can cause birth defects) based on animal studies. If you are pregnant, planning to become pregnant, or could become pregnant without using reliable contraception, Volibris is absolutely contraindicated. Women of childbearing potential must have a negative pregnancy test before starting treatment and use effective contraception throughout.
  • Breastfeeding: It is not known whether ambrisentan passes into human breast milk. Do not breastfeed while taking Volibris. Discuss alternative feeding options with your doctor.
  • Hypersensitivity: Do not take Volibris if you are allergic to ambrisentan, soy, or any of the other ingredients in the tablets.
  • Severe hepatic impairment: Volibris should not be used in patients with severe liver disease. Your doctor will assess your liver function before prescribing this medication.
  • Idiopathic pulmonary fibrosis (IPF): Volibris must not be used in patients with pulmonary fibrosis of unknown cause, with or without secondary pulmonary hypertension. Clinical trials (the ARTEMIS-IPF study) showed that ambrisentan increased the risk of disease progression and hospitalizations in IPF patients.

Warnings and Precautions

Before and during treatment with Volibris, talk to your doctor if any of the following apply to you:

  • Liver problems: Your doctor will perform liver function tests before starting treatment and may monitor them periodically. Signs of liver dysfunction include loss of appetite, nausea, vomiting, fever, abdominal pain, yellowing of the skin or whites of the eyes (jaundice), dark-colored urine, and itching. Report any of these symptoms immediately.
  • Anemia: Ambrisentan can cause a decrease in hemoglobin levels and red blood cell counts. Your doctor will check your blood before starting treatment and at regular intervals. Symptoms of anemia include fatigue, weakness, and shortness of breath. Sometimes blood transfusions are necessary.
  • Peripheral edema (swelling): Fluid retention causing swelling of the ankles, feet, or legs is a common effect of endothelin receptor antagonists. This is more likely to occur if you also have heart failure. Tell your doctor if you notice increased swelling, as dose adjustments or additional treatments may be needed.
  • Pulmonary veno-occlusive disease (PVOD): If you have pulmonary hypertension caused by blocked veins in the lungs, Volibris may worsen your condition. Signs include worsening breathlessness, low blood oxygen levels, and pulmonary edema. Contact your doctor immediately if these occur.

Pregnancy and Breastfeeding

Volibris can cause serious harm to an unborn baby. Animal studies have demonstrated teratogenic effects with ambrisentan, meaning the drug can cause birth defects. For this reason, Volibris is absolutely contraindicated during pregnancy. If you are a woman of childbearing potential, the following measures are essential:

  • You must use a reliable method of contraception throughout treatment with Volibris. Discuss the most appropriate method with your doctor.
  • Your doctor will require a pregnancy test before starting Volibris and at regular intervals during treatment.
  • If you become pregnant or suspect you may be pregnant while taking Volibris, contact your doctor immediately. Do not stop taking the medication without medical guidance, as abrupt discontinuation of PAH therapy can be dangerous.

It is not known whether ambrisentan is excreted in human breast milk. Because of the potential risk to the breastfed infant, breastfeeding is not recommended during treatment with Volibris.

Fertility

In men taking Volibris, there is a potential risk that the medication may reduce sperm count. If you have concerns about your fertility while taking this medication, discuss this with your doctor. The clinical significance of this finding is not fully established, but men planning to father children should be aware of this possibility.

Driving and Operating Machinery

Volibris may cause side effects such as low blood pressure, dizziness, and fatigue, which can affect your ability to drive or operate machinery safely. Additionally, the symptoms of PAH itself – including breathlessness, fatigue, and dizziness – may impair your capacity for these activities. Do not drive or use machines until you know how Volibris affects you.

Important Information About Ingredients

Volibris tablets contain small amounts of lactose. If your doctor has told you that you have an intolerance to certain sugars, contact your doctor before taking this medicine.

Volibris also contains lecithin derived from soy. If you are allergic to soy, you must not take this medicine.

The 5 mg and 10 mg tablets contain a coloring agent called Allura Red AC aluminum lake (E129), which may cause allergic reactions in some individuals.

This medicine contains less than 1 mmol (23 mg) of sodium per tablet, meaning it is essentially sodium-free.

How Does Volibris Interact with Other Drugs?

Quick Answer: Cyclosporine A significantly increases ambrisentan levels and requires dose limitation (maximum 5 mg daily in adults). Rifampicin may affect ambrisentan levels and requires closer monitoring. Volibris is commonly combined with PDE5 inhibitors (sildenafil, tadalafil) and prostanoids for PAH treatment, but additional monitoring is recommended.

Drug interactions with Volibris are clinically important and must be carefully managed. Ambrisentan is metabolized primarily by glucuronidation (via UGT enzymes) and by oxidative pathways involving CYP3A4 and CYP2C19. It is also a substrate of the organic anion transporting polypeptide (OATP) and P-glycoprotein (P-gp) transport systems. Medications that inhibit these pathways can increase ambrisentan exposure, potentially leading to increased side effects, while inducers may reduce effectiveness.

Major Interactions

Major Drug Interactions with Volibris
Interacting Drug Effect Clinical Significance
Cyclosporine A Approximately 2-fold increase in ambrisentan exposure (via OATP and P-gp inhibition) Maximum dose limited to 5 mg daily in adults; dose restrictions also apply in children
Rifampicin Single-dose studies showed transient increase then decrease in ambrisentan levels via conflicting OATP inhibition and CYP induction Close monitoring required when starting Volibris in patients already taking rifampicin

Minor Interactions and Common Co-Medications

Other Drug Interactions and Co-Medications
Interacting Drug Effect Clinical Significance
Sildenafil No clinically significant pharmacokinetic interaction observed Commonly used together for PAH; monitor for additive hypotension
Tadalafil No clinically significant pharmacokinetic interaction; proven combination in AMBITION trial Recommended combination per ESC/ERS guidelines; monitor side effects
Iloprost / Epoprostenol (prostanoids) No direct pharmacokinetic interaction expected May be used in combination; closer monitoring for hypotension and side effects
Warfarin No clinically significant effect on warfarin pharmacokinetics No dose adjustment required, but monitor INR as with any medication change
Ketoconazole (CYP3A4 inhibitor) Modest increase in ambrisentan levels Use with caution; monitor for increased side effects

Ambrisentan does not significantly inhibit or induce CYP enzymes (CYP1A2, CYP2C9, CYP2C19, CYP3A4) at clinically relevant concentrations. Therefore, it is unlikely to alter the metabolism of other drugs that are processed by these enzymes. However, always inform your doctor about all medications, supplements, and herbal products you are taking, as interactions may occur through mechanisms that have not yet been fully characterized.

PAH Combination Therapy

Volibris is frequently prescribed alongside other PAH-specific therapies. The combination of ambrisentan with tadalafil is particularly well-studied (AMBITION trial) and is now a cornerstone of PAH management. When used in combination, your doctor will monitor you more closely for side effects such as hypotension, headache, edema, and anemia, which may be more frequent or severe than with monotherapy.

What Is the Correct Dosage of Volibris?

Quick Answer: The standard adult dose is 5 mg once daily, which may be increased to 10 mg once daily. For children aged 8–17 years, the starting dose is based on body weight: 2.5 mg for children weighing 20–35 kg, and 5 mg for those weighing 35 kg or more. If taking cyclosporine A, the maximum dose is 5 mg daily for adults.

Always take Volibris exactly as your doctor has told you. Do not change your dose without consulting your doctor first. Volibris is taken orally as a film-coated tablet, once daily, with or without food. Swallow the tablet whole with a glass of water – do not split, crush, or chew the tablets. It is best to take the tablet at the same time each day to maintain consistent blood levels.

Adults

Standard Adult Dosing

Starting dose: 5 mg once daily

Maintenance dose: Your doctor may increase the dose to 10 mg once daily depending on your clinical response and tolerability.

With cyclosporine A: If you are taking cyclosporine A, do not exceed 5 mg of Volibris once daily.

Children and Adolescents (8 to 17 Years)

Pediatric Dosing of Volibris by Body Weight
Body Weight Starting Dose Notes
35 kg or more 5 mg once daily Doctor may increase dose based on response and tolerability
20 kg to less than 35 kg 2.5 mg once daily Doctor may increase dose based on response and tolerability

It is important that children attend their regular medical appointments, as the dose may need to be adjusted as they grow and gain weight. For children and adolescents weighing less than 50 kg who are also taking cyclosporine A, the maximum dose of Volibris is 2.5 mg once daily. For those weighing 50 kg or more and taking cyclosporine A, the maximum dose is 5 mg once daily.

Volibris should not be given to children under 8 years of age, as the safety and efficacy in this younger age group have not been established.

Elderly Patients

No dose adjustment is required for elderly patients. However, older adults may be more susceptible to certain side effects such as peripheral edema and hypotension. Your doctor will monitor you closely and adjust treatment as needed.

Missed Dose

If you forget to take a dose of Volibris, take it as soon as you remember. Then continue taking your medicine as prescribed. Do not take a double dose to compensate for the missed one. If you are unsure what to do, contact your doctor or pharmacist for advice.

Overdose

If you take more tablets than prescribed, you are more likely to experience side effects such as headache, flushing, dizziness, nausea, or low blood pressure (which can cause lightheadedness). Seek medical advice immediately if you have taken too many tablets. There is no specific antidote for ambrisentan overdose; treatment is supportive and symptomatic.

Do Not Stop Treatment Without Medical Advice

Volibris is a long-term treatment that you must continue taking to control your PAH. Do not stop taking Volibris unless your doctor tells you to do so. Abrupt discontinuation of PAH therapy can lead to a dangerous worsening of symptoms and disease progression.

How to Take the Tablets

The 5 mg and 10 mg tablets are supplied in special child-resistant blister packs. To remove a tablet: (1) tear along the perforated line to separate one blister pocket from the strip, (2) peel back the outer covering starting from the colored corner, and (3) gently push one end of the tablet through the foil backing. The 2.5 mg tablets are packaged in a bottle rather than blister packs.

What Are the Side Effects of Volibris?

Quick Answer: The most common side effects of Volibris include peripheral edema (swelling of ankles/feet), anemia, headache, dizziness, palpitations, nasal congestion, nausea, diarrhea, and fatigue. Serious side effects include allergic reactions, heart failure, and liver damage. When combined with tadalafil, additional effects such as flushing and vomiting may occur.

Like all medicines, Volibris can cause side effects, although not everybody gets them. The side effect profile may differ when Volibris is used alone versus in combination with other PAH therapies such as tadalafil. Your medical team will monitor you closely and manage side effects as they arise. It is important to report any new or worsening symptoms to your doctor promptly.

Serious Side Effects

The following serious side effects require immediate medical attention. Contact your doctor right away if you experience any of these:

Peripheral Edema (Swelling)

Very common – may affect more than 1 in 10 people

  • Swelling of the ankles, feet, and legs caused by fluid retention
  • More common in patients with concurrent heart failure
  • May require dose adjustment or additional diuretic therapy

Anemia (Low Red Blood Cell Count)

Very common – may affect more than 1 in 10 people

  • Fatigue, weakness, and shortness of breath
  • Usually occurs within the first few weeks of treatment
  • Sometimes requires blood transfusion
  • Regular blood tests are essential for monitoring

Allergic Reactions

Common – may affect up to 1 in 10 people

  • Skin rash, itching, swelling (usually of face, lips, tongue, or throat)
  • May cause difficulty breathing or swallowing
  • Seek immediate medical attention if severe

Heart Failure

Common – may affect up to 1 in 10 people

  • Shortness of breath, extreme tiredness
  • Swollen ankles and legs
  • Due to the heart not pumping enough blood

Low Blood Pressure (Hypotension)

Common – may affect up to 1 in 10 people

  • Dizziness, lightheadedness, fainting

Other Side Effects (Monotherapy)

Very Common

May affect more than 1 in 10 people

  • Headache
  • Dizziness
  • Palpitations (fast or irregular heartbeat)
  • Worsening shortness of breath shortly after starting treatment
  • Runny or stuffy nose, nasal congestion, sinus pain
  • Nausea
  • Diarrhea
  • Fatigue

Common

May affect up to 1 in 10 people

  • Blurred vision or other visual changes
  • Fainting (syncope)
  • Abnormal liver function test results
  • Runny nose (rhinorrhea)
  • Constipation
  • Abdominal pain
  • Chest pain or discomfort
  • Flushing (skin redness)
  • Vomiting
  • Weakness
  • Nosebleeds (epistaxis)
  • Skin rash

Uncommon

May affect up to 1 in 100 people

  • Liver damage (hepatotoxicity)
  • Autoimmune hepatitis (liver inflammation caused by the body’s own immune system)

Additional Side Effects with Tadalafil Combination

When Volibris is taken together with tadalafil (another PAH medication), the following additional side effects have been reported:

Common (with tadalafil)

May affect up to 1 in 10 people

  • Flushing (skin redness)
  • Vomiting
  • Chest pain or discomfort
  • Tinnitus (ringing in the ears)

Uncommon (with tadalafil)

May affect up to 1 in 100 people

  • Sudden hearing loss

The side effects observed in children and adolescents are expected to be similar to those in adults. If you or your child experience any side effects, including those not listed here, tell your doctor. You can also report suspected side effects to your national pharmacovigilance authority (e.g., EMA in Europe, FDA MedWatch in the United States, or MHRA Yellow Card Scheme in the United Kingdom).

How Should You Store Volibris?

Quick Answer: Store Volibris at room temperature with no special storage conditions required. Keep out of the reach and sight of children. Do not use after the expiry date printed on the packaging. Dispose of unused medication through your pharmacy – do not throw it in household waste or down the drain.

Keep this medicine out of the sight and reach of children. Do not use Volibris after the expiry date stated on the packaging after “EXP.” The expiry date refers to the last day of the stated month.

No special storage conditions are required for Volibris tablets. Store at room temperature, away from excessive heat and moisture. Keep the tablets in their original packaging until ready to use.

Do not dispose of any medicines via wastewater or household waste. Ask your pharmacist how to dispose of medicines you no longer use. These measures help to protect the environment.

What Does Volibris Contain?

Quick Answer: The active substance is ambrisentan, available in 2.5 mg, 5 mg, and 10 mg film-coated tablets. The 2.5 mg tablet is white and round; the 5 mg tablet is light pink and square; the 10 mg tablet is dark pink and oval. All tablets contain lactose and soy-derived lecithin as excipients.

Active Substance

The active substance is ambrisentan. Each film-coated tablet contains either 2.5 mg, 5 mg, or 10 mg of ambrisentan.

Inactive Ingredients (Excipients)

For 2.5 mg tablets: Lactose monohydrate, microcrystalline cellulose, croscarmellose sodium, magnesium stearate, polyvinyl alcohol, talc, titanium dioxide (E171), macrogol, and lecithin (soy) (E322).

For 5 mg and 10 mg tablets: Lactose monohydrate, microcrystalline cellulose, croscarmellose sodium, magnesium stearate, polyvinyl alcohol, talc, titanium dioxide (E171), macrogol, lecithin (soy) (E322), and Allura Red AC aluminum lake (E129).

Appearance and Pack Sizes

  • Volibris 2.5 mg: White, 7 mm round, convex film-coated tablet with “GS” embossed on one side and “K11” on the other. Supplied in a bottle containing 30 tablets.
  • Volibris 5 mg: Light pink, 6.6 mm square, convex film-coated tablet with “GS” embossed on one side and “K2C” on the other. Supplied in unit-dose blister packs of 10 × 1 or 30 × 1 tablets.
  • Volibris 10 mg: Dark pink, 9.8 mm × 4.9 mm oval, convex film-coated tablet with “GS” embossed on one side and “KE3” on the other. Supplied in unit-dose blister packs of 10 × 1 or 30 × 1 tablets.

Not all pack sizes may be marketed in all countries.

Marketing Authorization Holder and Manufacturer

Volibris is marketed by GlaxoSmithKline (Ireland) Limited, 12 Riverwalk, Citywest Business Campus, Dublin 24, Ireland. In the United States, ambrisentan is marketed under the brand name Letairis by Gilead Sciences.

Frequently Asked Questions About Volibris

Volibris (ambrisentan) is used to treat pulmonary arterial hypertension (PAH) – a condition characterized by abnormally high blood pressure in the arteries that carry blood from the heart to the lungs. PAH causes the heart to work harder, leading to symptoms like breathlessness, fatigue, dizziness, and chest pain. Volibris widens the pulmonary arteries, making it easier for the heart to pump blood through them and improving symptoms and exercise capacity. It is approved for adults, adolescents, and children aged 8 years and older.

No. Volibris must not be taken during pregnancy as it can cause serious birth defects in the unborn baby. Women of childbearing potential must use reliable contraception throughout treatment. Your doctor will perform a pregnancy test before starting Volibris and at regular intervals during treatment. If you become pregnant or suspect pregnancy while taking Volibris, contact your doctor immediately.

The most common side effects include peripheral edema (swelling of the ankles and feet), anemia (low red blood cell count), headache, dizziness, palpitations, nasal congestion, nausea, diarrhea, and fatigue. Worsening breathlessness may also occur shortly after starting treatment. Most of these side effects are manageable, but you should report any new or worsening symptoms to your doctor.

Yes. Volibris is commonly used in combination with other PAH-targeted therapies, particularly PDE5 inhibitors such as tadalafil or sildenafil. The landmark AMBITION trial demonstrated that initial combination therapy with ambrisentan and tadalafil reduced the risk of clinical failure by 50% compared with monotherapy. Current ESC/ERS guidelines recommend initial combination therapy for many PAH patients. Prostanoids (such as iloprost or epoprostenol) may also be added for patients who need more aggressive treatment.

Yes. Your doctor will perform blood tests before starting Volibris and at regular intervals during treatment. These tests primarily check your hemoglobin levels (to monitor for anemia) and liver function. Decreases in hemoglobin are common and usually occur within the first few weeks of treatment. Regular monitoring ensures that any changes are detected early and managed appropriately.

If you miss a dose, take it as soon as you remember. Then continue with your regular dosing schedule. Do not take a double dose to make up for the missed one. Try to take Volibris at the same time each day. If you have questions about what to do after a missed dose, contact your doctor or pharmacist.

References

  1. European Medicines Agency (EMA). Volibris (ambrisentan) – Summary of Product Characteristics. Last updated 2024. Available from: EMA EPAR.
  2. U.S. Food and Drug Administration (FDA). Letairis (ambrisentan) Prescribing Information. Revised 2024. Available from: FDA Drug Label.
  3. Galiè N, Olschewski H, Oudiz RJ, et al. Ambrisentan for the treatment of pulmonary arterial hypertension: results of the ambrisentan in pulmonary arterial hypertension, randomized, double-blind, placebo-controlled, multicenter, efficacy (ARIES) study 1 and 2. Circulation. 2008;117(23):3010–3019. doi:10.1161/CIRCULATIONAHA.107.742510.
  4. Galiè N, Barberà JA, Frost AE, et al. Initial Use of Ambrisentan plus Tadalafil in Pulmonary Arterial Hypertension (AMBITION). N Engl J Med. 2015;373(9):834–844. doi:10.1056/NEJMoa1413687.
  5. Humbert M, Kovacs G, Hoeper MM, et al. 2022 ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension. Eur Heart J. 2022;43(38):3618–3731. doi:10.1093/eurheartj/ehac237.
  6. Klinger JR, Elliott CG, Levine DJ, et al. Therapy for Pulmonary Arterial Hypertension in Adults: Update of the CHEST Guideline and Expert Panel Report. Chest. 2019;155(3):565–586. doi:10.1016/j.chest.2018.11.030.
  7. Raghu G, Behr J, Brown KK, et al. Treatment of idiopathic pulmonary fibrosis with ambrisentan: a parallel, randomized trial (ARTEMIS-IPF). Ann Intern Med. 2013;158(9):641–649. doi:10.7326/0003-4819-158-9-201305070-00003.
  8. World Health Organization (WHO). WHO Model List of Essential Medicines – 23rd List. Geneva: WHO; 2023.
  9. British National Formulary (BNF). Ambrisentan. National Institute for Health and Care Excellence (NICE). Updated 2025.
  10. Galiè N, Channick RN, Frantz RP, et al. Risk stratification and medical therapy of pulmonary arterial hypertension. Eur Respir J. 2019;53(1):1801889. doi:10.1183/13993003.01889-2018.

Editorial Team

This article was written and reviewed by the iMedic Medical Editorial Team, comprising licensed specialist physicians with expertise in pulmonology, cardiology, and clinical pharmacology.

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