Macitentan 10mg Tablets — Generic Opsumit® 10mg | Order Online

Macitentan 10mg Tablets are a prescription medicine containing macitentan 10mg as the active ingredient and the generic equivalent of Opsumit® 10mg, the reference brand developed by Janssen Pharmaceuticals (a Johnson & Johnson company). Macitentan is a dual endothelin receptor antagonist (ERA) — a medicine that blocks both endothelin A (ETA) and endothelin B (ETB) receptors — used in the long-term treatment of pulmonary arterial hypertension (PAH). PAH is a rare, progressive and life-threatening condition characterised by high blood pressure in the pulmonary arteries, leading to right heart failure. Macitentan 10mg is the only approved strength of this medicine and is taken once daily. Generic macitentan 10mg tablets are available internationally across the USA, UK, Australia, UAE, Germany, France, Russia, South Korea and worldwide.

Product Information

What Is Macitentan 10mg Used For?

Macitentan 10mg is indicated for the long-term treatment of pulmonary arterial hypertension (PAH) — WHO Group 1 pulmonary hypertension — in adult patients. PAH is defined by a mean pulmonary arterial pressure above 20 mmHg at rest due to pathological changes in the small pulmonary arteries, causing progressive right heart strain and failure.

Clinical Evidence — SERAPHIN Trial
The approval of macitentan is supported by the landmark SERAPHIN trial — a long-term, event-driven Phase 3 study in over 700 PAH patients. Macitentan 10mg significantly reduced the risk of the composite primary endpoint of morbidity and mortality (including disease progression, worsening PAH requiring hospitalisation, and death) compared to placebo. The SERAPHIN trial was notable for its long follow-up duration (up to 3.5 years) and use of a morbidity/mortality endpoint rather than exercise capacity alone.

United States: Opsumit® (macitentan) is FDA-approved for the treatment of PAH (WHO Group 1) to delay disease progression. It is available only through the Opsumit REMS (Risk Evaluation and Mitigation Strategy) programme due to teratogenicity risk.

United Kingdom / EU: Macitentan (Opsumit®) is EMA-approved for long-term treatment of PAH in adults, to reduce PAH-related morbidity and mortality as defined in the SERAPHIN trial. Used as monotherapy or in combination with other PAH therapies.

Australia: Macitentan 10mg Australia — Opsumit® and generic macitentan 10mg are subject to TGA registration. PBS subsidisation for PAH — confirm eligibility with your specialist or pharmacist.

UAE / Gulf: Subject to UAE Ministry of Health registration. Consult a UAE-licensed specialist for current macitentan 10mg UAE availability.

Germany: Macitentan 10mg Filmtabletten are available in Germany as Opsumit® 10mg and as generic macitentan 10mg products. All are prescription-only (rezeptpflichtig).

France: Macitentan 10mg comprimés pelliculés are available as Opsumit® and as generics, subject to HAS reimbursement and prescription requirements.

Russia: Мациентан 10 мг is available as Опсумит® 10 мг in Russia, requiring a valid prescription.

South Korea: 마시텐탄 10mg is registered for prescription use per MFDS-approved labeling.

Always follow the prescribing information applicable to your country and the guidance of your licensed PAH specialist.

How Macitentan 10mg Works

Macitentan is a dual endothelin receptor antagonist. Endothelin-1 (ET-1) is a potent vasoconstrictor peptide produced by vascular endothelial cells. In PAH, ET-1 levels are markedly elevated, driving:

• Sustained pulmonary vasoconstriction — narrowing of pulmonary blood vessels
• Vascular smooth muscle proliferation — structural remodelling of pulmonary arterial walls
• Fibrosis — scarring of pulmonary vascular tissue
• Inflammation — contributing to progressive disease

Macitentan blocks both ETA receptors (predominantly on vascular smooth muscle cells, mediating vasoconstriction and proliferation) and ETB receptors (on endothelial cells, where ET-1 clearance occurs). The dual receptor blockade produces sustained pulmonary vasodilation, reduces vascular remodelling and alleviates the haemodynamic burden on the right ventricle.

What distinguishes macitentan from earlier ERAs (bosentan, ambrisentan):

• Sustained receptor occupancy — macitentan and its active metabolite (ACT-132577) have high receptor binding affinity and slow dissociation, maintaining prolonged receptor blockade
• Tissue penetration — macitentan is highly lipophilic, achieving better penetration into vascular tissue where ET-1 acts
• Dual receptor blockade — unlike ambrisentan (ETA-selective), macitentan blocks both ETA and ETB receptors
• Reduced hepatotoxicity vs bosentan — the SERAPHIN trial showed no significant increase in aminotransferases vs placebo at the 10mg dose
• Once-daily dosing — simpler regimen supporting adherence in long-term PAH management

Macitentan 10mg in Combination PAH Therapy

Macitentan 10mg is frequently used as part of a combination PAH therapy regimen. Current PAH guidelines support combination therapy targeting multiple disease pathways simultaneously:

• Prostacyclin pathway — prostacyclin analogues (epoprostenol, treprostinil, iloprost) and prostacyclin receptor agonists (selexipag)
• Nitric oxide pathway — phosphodiesterase-5 inhibitors (sildenafil, tadalafil) and soluble guanylate cyclase stimulators (riociguat)
• Endothelin pathway — endothelin receptor antagonists including macitentan

Macitentan is approved for use both as monotherapy and in combination with PDE-5 inhibitors or prostacyclin analogues. The SERAPHIN trial included a significant proportion of patients on background PAH therapy (predominantly PDE-5 inhibitors), supporting its use in combination treatment.

Important: Macitentan must not be combined with riociguat due to the risk of hypotension.

Generic Macitentan 10mg vs Opsumit® 10mg

Opsumit® 10mg is the originator brand containing macitentan 10mg. Generic macitentan 10mg tablets contain the same active ingredient at the same strength but may differ in inactive ingredients, tablet appearance, packaging and manufacturer. Generic substitution rules vary by country — consult your pharmacist or PAH specialist before switching between branded and generic macitentan products.

Key Safety Information — Macitentan 10mg

Teratogenicity — Pregnancy Contraindication
Macitentan is highly teratogenic and is absolutely contraindicated in pregnancy. Animal studies have shown embryo-foetal lethality and teratogenicity at clinically relevant doses. In women of childbearing potential:

• A negative pregnancy test is required before starting macitentan
• Reliable contraception must be used throughout treatment and for one month after stopping
• Monthly pregnancy tests are required during treatment
• In the USA, these requirements are enforced through the Opsumit REMS programme — prescribers, pharmacies and patients must be enrolled

Hepatotoxicity
Although macitentan showed a more favourable hepatic safety profile than bosentan in the SERAPHIN trial, liver function monitoring is still recommended. Macitentan must be used with caution in patients with pre-existing hepatic impairment. Avoid in severe hepatic impairment.

Signs of liver injury requiring immediate medical attention:

• Unusual fatigue
• Nausea and vomiting
• Right upper abdominal pain
• Jaundice
• Dark urine

Anaemia
Macitentan can cause a decrease in haemoglobin and haematocrit. Haemoglobin should be checked before initiation and periodically during treatment. Macitentan is not recommended in patients with severe anaemia.

Pulmonary Oedema
If signs of pulmonary oedema develop during treatment, consider the possibility of pulmonary veno-occlusive disease (PVOD) — a contraindication to ERA use. Macitentan must be discontinued in confirmed or suspected PVOD.

Hypotension
Macitentan can cause vasodilation-related hypotension, particularly when combined with other vasodilatory medicines.

Contraindications

• Pregnancy (absolute contraindication)
• Women of childbearing potential not using reliable contraception
• Severe hepatic impairment
• Baseline aminotransferase values >3× upper limit of normal
• Concurrent use of riociguat
• Known hypersensitivity to macitentan or excipients

Drug Interactions

• Strong CYP3A4 inhibitors (ketoconazole, itraconazole, ritonavir) — significantly increase macitentan exposure; avoid
• Strong CYP3A4 inducers (rifampicin, carbamazepine) — significantly reduce macitentan efficacy; avoid
• Riociguat — contraindicated combination (risk of serious hypotension)
• PDE-5 inhibitors (sildenafil, tadalafil) — commonly combined; monitor for hypotension
• Cyclosporine — moderate CYP3A4 inhibition; use with caution

Always read the patient information leaflet and prescribing information applicable to your country.

Macitentan 10mg — Availability by Country

Frequently Asked Questions — Macitentan 10mg

What is Macitentan 10mg used for?
Macitentan 10mg is used for the long-term treatment of pulmonary arterial hypertension (PAH — WHO Group 1) in adults. It delays disease progression, reduces hospitalisation and improves outcomes as demonstrated in the SERAPHIN trial. It is taken once daily and used as monotherapy or in combination with other PAH medicines.

Is Macitentan 10mg the generic for Opsumit® 10mg?
Yes. Opsumit® 10mg is the originator brand containing macitentan 10mg. Generic macitentan 10mg film-coated tablets contain the same active ingredient and strength. Inactive ingredients, appearance and manufacturer may differ.

Is 10mg the only available strength of Macitentan?
Yes. Macitentan 10mg is the only approved strength. There is no 5mg or 2.5mg dose — the 10mg once-daily dose is the standard dose for all adult PAH patients.

Why is Macitentan contraindicated in pregnancy?
Macitentan is highly teratogenic — it causes severe birth defects and embryo-foetal death in animal studies. It must not be used during pregnancy. Women of childbearing potential require monthly pregnancy testing and reliable contraception throughout treatment and for one month after stopping.

What is the Opsumit REMS programme?
In the USA, Opsumit® can only be prescribed, dispensed and received through the REMS (Risk Evaluation and Mitigation Strategy) programme due to the teratogenicity risk. Prescribers, pharmacies and female patients must all be enrolled. Male patients are not subject to the same REMS requirements.

How does Macitentan differ from Bosentan and Ambrisentan?
All three are endothelin receptor antagonists but differ in selectivity, pharmacokinetics and safety profile. Macitentan blocks both ETA and ETB receptors (like bosentan) with sustained receptor occupancy and better tissue penetration. It showed a more favourable hepatic safety profile than bosentan in clinical trials. Ambrisentan is ETA-selective. Macitentan’s long-term morbidity/mortality data from SERAPHIN is a key clinical differentiator.

Can Macitentan 10mg be used with Sildenafil or Tadalafil?
Yes. Macitentan is commonly combined with PDE-5 inhibitors such as sildenafil or tadalafil as part of combination PAH therapy targeting multiple disease pathways. Monitor for hypotension when combining vasodilatory medicines.

Can I buy Macitentan 10mg tablets online?
Macitentan 10mg is prescription-only in all major markets. In the USA it is only available through the Opsumit REMS programme. PAH is a specialist-managed condition — macitentan must be prescribed by and used under the supervision of a PAH specialist.

Is Macitentan 10mg available in Australia?
Macitentan 10mg products are registered on the ARTG. PBS subsidisation for PAH depends on eligibility criteria. Confirm current PBS status with your PAH specialist or pharmacist.

What is Macitentan 10mg in Germany?
Macitentan 10mg Filmtabletten are available in Germany as Opsumit® 10mg and as generic macitentan 10mg products from multiple manufacturers. All are prescription-only (rezeptpflichtig) and restricted to specialist prescribing for PAH.

Medical Disclaimer

This information is provided for educational and commercial reference purposes only and is not a substitute for professional medical advice, diagnosis or treatment. Macitentan 10mg is a prescription-only medicine for a rare and serious condition — pulmonary arterial hypertension — and carries important risks including teratogenicity, hepatotoxicity and anaemia. In the USA it is only available through the Opsumit REMS programme. It must be prescribed and managed by a qualified PAH specialist. Always use according to the applicable prescribing information and the advice of a licensed healthcare professional in your country.

Last Updated: September 25, 2026