Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.
Quick facts
- Drug class
- Endothelin Receptor Antagonist [EPC], Endothelin Receptor Antagonists [MoA]
- How it is given
- oral
- Type
- human prescription drug
- RxNorm ID
- 1442137
We do not publish dosing. How much of this medicine to take, how often, and for how long depends on your age, weight, kidney and liver function, other conditions and other medicines. That is a decision for the person who prescribes or dispenses it. Follow the directions on your own pack and ask your pharmacist if anything is unclear.
What it is used to treat
Macitentan tablets are an endothelin receptor antagonist (ERA) indicated for the treatment of pulmonary arterial hypertension (PAH, WHO Group I) in adults to reduce the risks of disease progression and hospitalization for PAH (1.1). 1.1 Pulmonary Arterial Hypertension Macitentan tablets are an endothelin receptor antagonist (ERA) indicated for the treatment of pulmonary arterial hypertension (PAH, WHO Group I) in adults to reduce the risks of disease progression and hospitalization for PAH. Effectiveness was established in a long-term study in PAH patients with predominantly WHO Functional Class II-III symptoms treated for an average of 2 years. Patients had idiopathic and heritable PAH (57%), PAH caused by connective tissue disorders (31%), and PAH caused by congenital heart disease with repaired shunts (8%) [see Clinical Studies (14.1)] .
About this medicine
Macitentan is an endothelin receptor antagonist. The chemical name of macitentan is N-[5-(4-Bromophenyl)-6-[2-[(5-bromo-2-pyrimidinyl)oxy]ethoxy]-4-pyrimidinyl]-N'-propylsulfamide. It has a molecular formula of C 19 H 20 Br 2 N 6 O 4 S and a molecular weight of 588.27. Macitentan is achiral and has the following structural formula: Macitentan is a crystalline powder that is insoluble in water. In the solid state macitentan is very stable, is not hygroscopic, and is not light sensitive. Macitentan tablets are available as a 10 mg film-coated tablet for once daily oral administration. The tablets include the following inactive ingredients: cellulose microcrystalline, magnesium stearate, mannitol 25, polysorbate 80, povidone K- 30, silicified microcrystalline cellulose, and sodium starch glycolate (Type-A). The tablets are film-coated with a coating material containing lecithin (soya), polyvinyl alcohol-part, hydrolyzed, talc, titanium dioxide, and xanthan gum. structure
Who should not take it
Pregnancy ( 4.1 ) Hypersensitivity ( 4.2 ) 4.1 Pregnancy Macitentan tablets may cause fetal harm when administered to a pregnant woman. Macitentan tablets are contraindicated in females who are pregnant. Macitentan tablets were consistently shown to have teratogenic effects when administered to animals. If macitentan tablets are used during pregnancy, advise the patient of the potential risk to a fetus [see Warnings and Precautions (5.1) and Use in Specific Populations (8.1)] . 4.2 Hypersensitivity Macitentan tablets is contraindicated in patients with a history of a hypersensitivity reaction to macitentan or any component of the product [see Adverse Reactions (6.2)] .
Warnings
WARNING: EMBRYO-FETAL TOXICITY Macitentan tablets are contraindicated for use during pregnancy because it may cause fetal harm based on animal data [see Contraindications (4.1), Warnings and Precautions (5.1), Use in Specific Populations (8.1)] . Therefore, for females of reproductive potential, exclude pregnancy before the start of treatment with macitentan tablets. Advise use of effective contraception before the initiation of treatment, during treatment, and for one month after stopping treatment with macitentan tablets [see Dosage and Administration (2.2), Use in Specific Populations (8.3)] . When pregnancy is detected, discontinue macitentan tablets as soon as possible [see Warnings and Precautions (5.1)] .
Warnings and cautions
ERAs cause hepatotoxicity and liver failure. Obtain baseline liver enzymes and monitor as clinically indicated ( 5.2 ). Fluid retention may require intervention ( 5.3 ). Decreases in hemoglobin ( 5.4 ). Pulmonary edema in patients with pulmonary veno-occlusive disease. If confirmed, discontinue treatment ( 5.5 ). Decreases in sperm count have been observed in patients taking ERAs ( 5.6 ). 5.1 Embryo-fetal Toxicity Based on data from animal reproduction studies, macitentan tablets may cause fetal harm when administered to a pregnant patient and is contraindicated during pregnancy. The available human data for ERAs do not establish the presence or absence of major birth defects related to the use of macitentan tablets. Advise patients who can become pregnant of the potential risk to a fetus. Obtain a pregnancy test prior to initiation of therapy with macitentan tablets. Advise patients who can become pregnant to use effective contraceptive methods prior to initiation of treatment, during treatment, and for one month after discontinuation of treatment with macitentan tablets. When pregnancy is detected, discontinue use as soon as possible [see Dosage and Administration (2.2), Contraindications (4.1), and Use in Specific Populations (8.1, 8.3)] . 5.2 Hepatotoxicity ERAs have caused elevations of aminotransferases, hepatotoxicity, and liver failure. The incidence of elevated aminotransferases in the study of macitentan tablets in PAH is shown in Table 1. Table 1: Incidence of Elevated Aminotransferases in the SERAPHIN Study Macitentan tablets 10 mg ( N=242 ) Placebo (N=249) >3 x ULN 3.4% 4.5% >8 x ULN 2.1% 0.4% In the placebo-controlled study of macitentan tablets, discontinuations for hepatic adverse events were 3.3% in the macitentan tablets 10 mg group vs. 1.6% for placebo. Obtain liver enzyme tests prior to initiation of macitentan tablets and repeat during treatment as clinically indicated [see Adverse Reactions (6.2)] . Advise patients to report symptoms suggesting hepatic injury (nausea, vomiting, right upper quadrant pain, fatigue, anorexia, jaundice, dark urine, fever, or itching). […]
Reported side effects
Clinically significant adverse reactions that appear in other sections of the labeling include: Embryo-fetal Toxicity [see Warnings and Precautions (5.1)] Hepatotoxicity [see Warnings and Precautions (5.2)] Fluid Retention [see Warnings and Precautions (5.3)] Decrease in Hemoglobin [see Warnings and Precautions (5.4)] Most common adverse reactions (more frequent than placebo by ≥3%) are anemia, nasopharyngitis/pharyngitis, bronchitis, headache, influenza, and urinary tract infection ( 6.1 ). To report SUSPECTED ADVERSE REACTIONS, contact Torrent Pharma Inc. at 1-800-912-9561 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trial Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. Safety data for macitentan tablets were obtained primarily from one placebo-controlled clinical study in 742 patients with PAH (SERAPHIN study) [see Clinical Studies (14.1)] . The exposure to macitentan tablets in this trial was up to 3.6 years with a median exposure of about 2 years (N=542 for 1 year; N=429 for 2 years; and N=98 for more than 3 years). The overall incidence of treatment discontinuations because of adverse events was similar across macitentan tablets 10 mg and placebo treatment groups (approximately 11%). Table 2 presents adverse reactions more frequent on macitentan tablets than on placebo by ≥3%. Table 2: Adverse Reactions Adverse Reaction Macitentan tablets 10 mg ( N=242 ) (%) Placebo (N=249) (%) Anemia 13 3 Nasopharyngitis/pharyngitis 20 13 Bronchitis 12 6 Headache 14 9 Influenza 6 2 Urinary tract infection 9 6 6.2 Postmarketing Experience The following adverse reactions have been identified during post-approval use of macitentan tablets. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. […]
Interactions with other medicines
Strong CYP3A4 inducers (rifampin) reduce exposure to macitentan: avoid co-administration with macitentan tablets ( 7.1 , 12.3 ). Strong CYP3A4 inhibitors (ketoconazole, ritonavir) increase exposure to macitentan: avoid co-administration with macitentan tablets ( 7.2 , 12.3 ). Moderate dual CYP3A4 and CYP2C9 inhibitors (fluconazole, amiodarone) or use of combined CYP3A4 and CYP2C9 inhibitors may increase exposure to macitentan: avoid co-administration with macitentan tablets ( 7.3 , 12.3 ). 7.1 Strong CYP3A4 Inducers Strong inducers of CYP3A4 such as rifampin significantly reduce macitentan exposure. Concomitant use of macitentan tablets with strong CYP3A4 inducers should be avoided [see Clinical Pharmacology (12.3)] . 7.2 Strong CYP3A4 Inhibitors Concomitant use of strong CYP3A4 inhibitors like ketoconazole approximately double macitentan exposure. Many HIV drugs like ritonavir are strong inhibitors of CYP3A4. Avoid concomitant use of macitentan tablets with strong CYP3A4 inhibitors [see Clinical Pharmacology (12.3)] . Use other PAH treatment options when strong CYP3A4 inhibitors are needed as part of HIV treatment [see Clinical Pharmacology (12.3)] . 7.3 Moderate Dual or Combined CYP3A4 and CYP2C9 Inhibitors Concomitant use of moderate dual inhibitors of CYP3A4 and CYP2C9 such as fluconazole is predicted to increase macitentan exposure approximately 4-fold based on physiologically based pharmacokinetic (PBPK) modeling. Avoid concomitant use of macitentan with moderate dual inhibitors of CYP3A4 and CYP2C9 (such as fluconazole and amiodarone) [see Clinical Pharmacology (12.3)] . Concomitant treatment of both a moderate CYP3A4 inhibitor and moderate CYP2C9 inhibitor with macitentan should also be avoided [see Clinical Pharmacology (12.3)] .
Use in specific groups
Lactation: Advise not to breastfeed. ( 8.2 ) 8.1 Pregnancy Risk Summary Based on data from animal reproduction studies, macitentan tablets may cause embryo-fetal toxicity, including birth defects and fetal death, when administered to a pregnant female and is contraindicated during pregnancy. There are risks to the mother and the fetus associated with pulmonary arterial hypertension in pregnancy [ see Clinical Considerations] . Available data from postmarketing reports and published literature over decades of use with ERAs in the same class as macitentan have not identified an increased risk of major birth defects; however, these data are limited. Methodological limitations of these postmarketing reports and published literature include lack of a control group; limited information regarding dose, duration, and timing of drug exposure; and missing data. These limitations preclude establishing a reliable estimate of the risk of adverse fetal and neonatal outcomes with maternal ERA use. Macitentan was teratogenic in rabbits and rats at all doses tested. If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, advise the patient of the risk to a fetus [see Contraindications (4.1)]. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively. Clinical Considerations Disease-associated Maternal and/or Embryo/Fetal Risk In patients with pulmonary arterial hypertension, pregnancy is associated with an increased rate of maternal and fetal morbidity and mortality, including spontaneous abortion, intrauterine growth restriction and premature labor. Data Animal Data In both rabbits and rats, there were cardiovascular and mandibular arch fusion abnormalities. […]
If too much is taken
Macitentan tablets has been administered as a single dose of up to and including 600 mg to healthy subjects (60 times the approved dosage). Adverse reactions of headache, nausea and vomiting were observed. In the event of an overdose, standard supportive measures should be taken, as required. Dialysis is unlikely to be effective because macitentan is highly protein-bound.
Before you take anything new
Tell your pharmacist or doctor about every medicine you take — including ones bought without a prescription, herbal products and supplements. Interactions are one of the most common avoidable causes of harm from medicines, and a pharmacist can check your full list in a couple of minutes.
This page is built from the openFDA record of the U.S. Food and Drug Administration's approved labelling for this product, effective 18 May 2026. Label text has been shortened and reformatted for readability; safety wording has not been altered in meaning. FDA labelling describes products approved in the United States — brand names, strengths, formulations and approved uses may differ in your country. Always read the leaflet that comes with your own pack. PocketsInfo is not affiliated with, and is not endorsed by, the FDA. Retrieved 2026-07-30.