Bosentan

FDA Drug Information • Also known as: Bosentan, Tracleer

Brand Names: Bosentan, Tracleer
Dosage Form: TABLET, FILM COATED
Product Type: DRUG FOR FURTHER PROCESSING

⚠ Boxed Warning (Black Box)

WARNING: RISKS OF HEPATOTOXICITY and EMBRYO-FETAL TOXICITY Because of the risk of hepatotoxicity, TRACLEER is available only through a restricted program called the Bosentan Risk Evaluation and Mitigation Strategy (REMS). Under the Bosentan REMS, prescribers, patients, and pharmacies must enroll in the program [see Warnings and Precautions (5.2) ] . WARNING: RISKS OF HEPATOTOXICITY and EMBRYO-FETAL TOXICITY See full prescribing information for complete boxed warning. TRACLEER is available only through a restricted distribution program called the Bosentan Risk Evaluation and Mitigation Strategy (REMS) because of the risk of hepatotoxicity ( 5.2 ): Elevations of liver aminotransferases (ALT, AST) and liver failure have been reported with TRACLEER ( 5.1 ). Measure liver aminotransferases prior to initiation of treatment and then monthly ( 2.1 , 5.1 ). Discontinue TRACLEER if aminotransferase elevations are accompanied by signs or symptoms of liver dysfunction or injury or increases in bilirubin ≥2×ULN ( 2.4 , 5.1 ). Based on animal data, TRACLEER may cause fetal harm if used during pregnancy ( 4.1 , 5.3 , 8.1 ). Females of reproductive potential: Exclude pregnancy before initiating treatment. Use effective contraception prior to initiation of treatment, during treatment and for one month after stopping TRACLEER ( 2.1 , 4.1 , 5.3 , 8.1 , 8.3 ). When pregnancy is detected, discontinue TRACLEER as soon as possible ( 5.3 ). Hepatotoxicity In clinical studies, TRACLEER caused at least 3-fold upper limit of normal (ULN) elevation of liver aminotransferases (ALT and AST) in about 11% of patients, accompanied by elevated bilirubin in a small number of cases. Because these changes are a marker for potential serious hepatotoxicity, serum aminotransferase levels must be measured prior to initiation of treatment and then monthly [see Dosage and Administration (2.4) , Warnings and Precautions (5.1) ] . In the postmarketing period, in the setting of close monitoring, rare cases of unexplained hepatic cirrhosis were reported after prolonged (>12 months) therapy with TRACLEER in patients with multiple comorbidities and drug therapies. There have also been reports of liver failure. The contribution of TRACLEER in these cases could not be excluded. In at least one case, the initial presentation (after >20 months of treatment) included pronounced elevations in aminotransferases and bilirubin levels accompanied by non-specific symptoms, all of which resolved slowly over time after discontinuation of TRACLEER. This case reinforces the importance of strict adherence to the monthly monitoring schedule for the duration of treatment and the treatment algorithm, which includes stopping TRACLEER with a rise of aminotransferases accompanied by signs or symptoms of liver dysfunction [see Dosage and Administration (2.4) ] . Elevations in aminotransferases require close attention [see Dosage and Administration (2.4) ] . TRACLEER should generally be avoided in patients with elevated aminotransferases (>3×ULN) at baseline because monitoring for hepatotoxicity may be more difficult. If liver aminotransferase elevations are accompanied by clinical symptoms of hepatotoxicity (such as nausea, vomiting, fever, abdominal pain, jaundice, or unusual lethargy or fatigue) or increases in bilirubin ≥2×ULN, treatment with TRACLEER should be stopped. There is no experience with the reintroduction of TRACLEER in these circumstances. Embryo-Fetal Toxicity TRACLEER is contraindicated for use during pregnancy because it may cause fetal harm if used by pregnant females based on animal data. Therefore, for females of reproductive potential, exclude pregnancy before the start of treatment with TRACLEER. Advise use of effective contraception before initiation, during treatment and for one month after stopping TRACLEER. When pregnancy is detected, discontinue TRACLEER as soon as possible [see Dosage and Administration (2.1) , Contraindications (4.1) , Warnings and Precautions (5.3) , Drug Interactions (7.2) , Use in Specific Populations (8.1 , 8.3) ] .

Description

11 DESCRIPTION TRACLEER ® is the proprietary name for bosentan, an endothelin receptor antagonist that belongs to a class of highly substituted pyrimidine derivatives, with no chiral centers. It is designated chemically as 4-tert-butyl-N-[6-(2-hydroxy-ethoxy)-5-(2-methoxy-phenoxy)-[2,2´]-bipyrimidin-4-yl]- benzenesulfonamide monohydrate and has the following structural formula: Bosentan has a molecular weight of 569.64 and a molecular formula of C 27 H 29 N 5 O 6 S∙H 2 O. Bosentan is a white to yellowish powder. It is poorly soluble in water (1.0 mg/100 mL) and in aqueous solutions at low pH (0.1 mg/100 mL at pH 1.1 and 4.0; 0.2 mg/100 mL at pH 5.0). Solubility increases at higher pH values (43 mg/100 mL at pH 7.5). In the solid state, bosentan is very stable, is not hygroscopic and is not light sensitive. TRACLEER is available as 62.5 mg and 125 mg film-coated tablets for oral administration, and contains the following excipients: corn starch, ethylcellulose, glyceryl behenate, hydroxypropylmethylcellulose, iron oxide red, iron oxide yellow, magnesium stearate, povidone, pregelatinized starch, sodium starch glycolate, talc, titanium dioxide, and triacetin. Each TRACLEER 62.5 mg tablet contains 64.54 mg of bosentan monohydrate, equivalent to 62.5 mg of anhydrous bosentan. Each TRACLEER 125 mg tablet contains 129.08 mg of bosentan monohydrate, equivalent to 125 mg of anhydrous bosentan. TRACLEER is also available as a 32 mg tablet for oral suspension and contains the following excipients: acesulfame potassium, aspartame (E951), calcium hydrogen phosphate anhydrous, cellulose microcrystalline, croscarmellose sodium, magnesium stearate, silica colloidal anhydrous, tartaric acid, and tutti frutti flavor. Each dispersible tablet contains 1.87 mg of phenylalanine. Each dispersible tablet contains 33.045 mg of bosentan monohydrate, equivalent to 32 mg anhydrous bosentan. Chemical Structure

What Is Bosentan Used For?

1 INDICATIONS AND USAGE TRACLEER is indicated for the treatment of pulmonary arterial hypertension (PAH) (WHO Group 1): in adults to improve exercise ability and to decrease clinical worsening. Studies establishing effectiveness included predominantly patients with WHO Functional Class II-IV symptoms and etiologies of idiopathic or heritable PAH (60%), PAH associated with connective tissue diseases (21%), and PAH associated with congenital heart disease with left-to-right shunts (18%) [see Clinical Studies (14.1) ] . in pediatric patients aged 3 years and older with idiopathic or congenital PAH to improve pulmonary vascular resistance (PVR), which is expected to result in an improvement in exercise ability. TRACLEER is an endothelin receptor antagonist indicated for the treatment of pulmonary arterial hypertension (PAH) (WHO Group 1): in adults to improve exercise ability and to decrease clinical worsening. Studies establishing effectiveness included predominantly patients with WHO Functional Class II-IV symptoms and etiologies of idiopathic or heritable PAH (60%), PAH associated with connective tissue diseases (21%), and PAH associated with congenital heart disease with left-to-right shunts (18%) ( 1 ). in pediatric patients aged 3 years and older with idiopathic or congenital PAH to improve pulmonary vascular resistance (PVR), which is expected to result in an improvement in exercise ability ( 1 ).

Dosage and Administration

2 DOSAGE AND ADMINISTRATION Patients older than 12 years of age: initiate at 62.5 mg orally twice daily; for patients weighing greater than 40 kg, increase to 125 mg orally twice daily after 4 weeks ( 2.2 ). Patients 12 years of age and younger: dosage is based on weight, see Table 1 ( 2.2 ). Reduce the dose and closely monitor patients developing aminotransferase elevations more than 3×Upper Limit of Normal (ULN) ( 2.4 ). 2.1 Required Monitoring Healthcare professionals who prescribe TRACLEER must enroll in the Bosentan REMS and must comply with the required monitoring to minimize the risks associated with TRACLEER [see Warnings and Precautions (5.2) ]. Measure liver aminotransferase levels prior to initiation of treatment and then monthly [see Boxed Warning , Warnings and Precautions (5.1 , 5.2) ]. Exclude pregnancy before initiating treatment with TRACLEER in females of reproductive potential [see Boxed Warning , Contraindications (4.1) , Warnings and Precautions (5.3) , Use in Specific Populations (8.1 , 8.3) ] . 2.2 Recommended Dosage Administer TRACLEER orally following the dosing recommendations in Table 1. Doses above 125 mg twice daily did not appear to confer additional benefit sufficient to offset the increased risk of hepatotoxicity. Table 1: Dosing Recommendations Initial 4 weeks Maintenance (after 4 weeks) Patients >12 years of age and >40 kg 62.5 mg twice daily 125 mg twice daily Patients >12 years of age and <40 kg 62.5 mg twice daily 62.5 mg twice daily Patients ≤12 years of age ≥4–8 kg 16 mg twice daily 16 mg twice daily >8–16 kg 32 mg twice daily 32 mg twice daily >16–24 kg 48 mg twice daily 48 mg twice daily >24–40 kg 64 mg twice daily 64 mg twice daily 2.3 Administration TRACLEER film-coated tablets and tablets for oral suspension (dispersible tablets) should be administered orally twice daily. Disperse tablets for oral suspension, or dispersible tablet half, in a minimal amount of water immediately before administration. Store divided dispersible tablet pieces at 20 ºC to 25 ºC (68 ºF to 77 ºF) in the opened blister for up to 7 days. 2.4 Dosage Adjustments for Aminotransferase Elevations If aminotransferase levels increase, adjust monitoring and treatment plan according to Table 2. Discontinue TRACLEER if liver aminotransferase elevations are accompanied by clinical symptoms of hepatotoxicity (such as nausea, vomiting, fever, abdominal pain, jaundice, or unusual lethargy or fatigue) or bilirubin ≥2 × Upper Limit of Normal (ULN). There is no experience with the reintroduction of TRACLEER in these circumstances. Table 2: Dosage Adjustment and Monitoring in Patients Developing Aminotransferase Elevations >3×ULN ALT/AST levels Treatment and monitoring recommendations >3 and ≤5 × ULN Confirm by another aminotransferase test; if confirmed, in adults and pediatric patients >12 years and >40 kg , reduce the daily dose to 62.5 mg twice daily or interrupt treatment, and monitor aminotransferase levels at least every 2 weeks. If the...

Side Effects (Adverse Reactions)

6 ADVERSE REACTIONS The following important adverse reactions are described elsewhere in the labeling: Hepatotoxicity [see Boxed Warning , Warnings and Precautions (5.1) ] Embryo-fetal Toxicity [see Boxed Warning , Warnings and Precautions (5.3) ] Fluid Retention [see Warnings and Precautions (5.4) ] Common adverse reactions (≥3% more than placebo) for the film-coated tablet are respiratory tract infection and anemia ( 6.1 ). Common adverse reactions (≥15%) for the dispersible tablet are upper respiratory tract infections and pyrexia ( 6.1 ). To report SUSPECTED ADVERSE REACTIONS, contact Actelion at 1-800-526-7736 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the 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 practice. Safety data on TRACLEER were obtained from 13 clinical studies (9 placebo-controlled and 4 open-label) in 870 adult patients with PAH and other diseases. Doses up to 8 times the currently recommended clinical dose (125 mg twice daily) were administered for a variety of durations. The exposure to TRACLEER in these trials ranged from 1 day to 4.1 years (n=94 for 1 year; n=61 for 1.5 years; and n=39 for more than 2 years). Exposure of PAH patients (n=328) to TRACLEER ranged from 1 day to 1.7 years (n=174 more than 6 months and n=28 more than 12 months). Treatment discontinuations due to adverse events other than those related to pulmonary hypertension during the clinical trials in adult patients with PAH were more frequent on TRACLEER (6%; 15/258 patients) than on placebo (3%; 5/172 patients). In this database the only cause of discontinuations >1% and occurring more often on TRACLEER was abnormal liver function. The adverse drug events that occurred in ≥3% of the TRACLEER-treated patients and were more common on TRACLEER in placebo-controlled trials in PAH at doses of 125 or 250 mg twice daily are shown in Table 3: Table 3: Adverse Events Note: only AEs with onset from start of treatment to 1 calendar day after end of treatment are included. All reported events (at least 3%) are included except those too general to be informative, and those not reasonably associated with the use of the drug because they were associated with the condition being treated or are very common in the treated population. Occurring in ≥3% of Patients Treated with TRACLEER 125-250 mg Twice Daily and More Common on TRACLEER in Placebo-Controlled Studies in Pulmonary Arterial Hypertension Adverse Event TRACLEER n=258 Placebo n=172 No. % No. % Respiratory Tract Infection Respiratory Tract Infection combines the terms "Nasopharyngitis", "Upper Respiratory Tract Infection" and "Respiratory Tract Infection". Combined data from Study 351, BREATHE-1 and EARLY 56 22% 30 17% Headache 39 15% 25 14% Edema 28 11% 16 9% Chest Pain 13 5% 8 5% Syncope 12 5% 7 4% Flushing 10 4% 5 3% Hypotension 10 4% 3 2% Sinusitis 9 4% 4 2% Arthralgia 9 4% 3 2% Serum Aminotransferases, abnormal 9 4% 3 2% Palpitations 9 4% 3 2% Anemia 8 3% - - TRACLEER was evaluated for safety in 119 pediatric patients in uncontrolled studies. The safety profile was similar to that observed in adult patients with PAH. Decreased Sperm Counts An open-label, single-arm, multicenter, safety study evaluated the effect on testicular function of TRACLEER 62.5 mg twice daily for 4 weeks, followed by 125 mg twice daily for 5 months. Twenty-five male patients with WHO functional class III and IV PAH and normal baseline sperm count were enrolled. Twenty-three completed the study and 2 discontinued due to adverse events not related to testicular function. There was a decline in sperm count of at least 50% in 25% of the patients after 3 or 6 months of treatment with TRACLEER. Sperm count remained within the normal range in all 22 patients with data after 6 months and...

Drug Interactions

7 DRUG INTERACTIONS Cytochrome P450: Coadministration of TRACLEER with drugs metabolized by CYP2C9 and CYP3A can increase exposure to TRACLEER and/or the coadministered drug ( 4.2 , 4.3 , 7.1 ). Hormonal contraceptives: TRACLEER use decreases contraceptive exposure and reduces effectiveness ( 7.2 ). 7.1 Cytochrome P450 Drug Interactions Bosentan is metabolized by CYP2C9 and CYP3A. Inhibition of these enzymes may increase the plasma concentration of bosentan [see Clinical Pharmacology (12.3) ] . Concomitant administration of both a CYP2C9 inhibitor (such as fluconazole or amiodarone) and a strong CYP3A inhibitor (e.g., ketoconazole, itraconazole) or a moderate CYP3A inhibitor (e.g., amprenavir, erythromycin, fluconazole, diltiazem) with TRACLEER will likely lead to large increases in plasma concentrations of bosentan. Co-administration of such combinations of a CYP2C9 inhibitor plus a strong or moderate CYP3A inhibitor with TRACLEER is not recommended. Bosentan is an inducer of CYP3A and CYP2C9. Consequently plasma concentrations of drugs metabolized by these two isozymes will be decreased when TRACLEER is co-administered. Bosentan had no relevant inhibitory effect on any CYP isozyme in vitro (CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP3A). Consequently, TRACLEER is not expected to increase the plasma concentrations of drugs metabolized by these enzymes. Figure 1. CYP3A induction-mediated effect of bosentan on other drugs Figure 2. Effect of other drugs on bosentan Figure 1 Figure 2 7.2 Hormonal Contraceptives Hormonal contraceptives, including oral, injectable, transdermal, and implantable forms, may not be reliable when TRACLEER is co-administered. Females should practice additional methods of contraception and not rely on hormonal contraception alone when taking TRACLEER [see Use in Specific Populations (8.3) ] . An interaction study demonstrated that co-administration of bosentan and a combination oral hormonal contraceptive produced average decreases of norethindrone and ethinyl estradiol levels of 14% and 31%, respectively. However, decreases in exposure were as much as 56% and 66%, respectively, in individual subjects.

Contraindications

4 CONTRAINDICATIONS Pregnancy ( 4.1 ). Use with Cyclosporine A ( 4.2 ). Use with Glyburide ( 4.3 ). Hypersensitivity ( 4.4 ). 4.1 Pregnancy Use of TRACLEER is contraindicated in females who are pregnant [see Boxed Warning , Dosage and Administration (2.1) , Warnings and Precautions (5.3) , Use in Specific Populations (8.1) ] . 4.2 Use with Cyclosporine A Co-administration of cyclosporine A and bosentan resulted in markedly increased plasma concentrations of bosentan. Therefore, concomitant use of TRACLEER and cyclosporine A is contraindicated [see Drug Interactions (7.1) ] . 4.3 Use with Glyburide An increased risk of liver enzyme elevations was observed in patients receiving glyburide concomitantly with bosentan. Therefore co-administration of glyburide and TRACLEER is contraindicated [see Drug Interactions (7.1) ] . 4.4 Hypersensitivity TRACLEER is contraindicated in patients who are hypersensitive to bosentan or any component of the product. Observed reactions include Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS), anaphylaxis, rash, and angioedema [see Adverse Reactions (6.2) , Description (11) ] .

Pregnancy and Breastfeeding

8.1 Pregnancy Risk Summary Based on data from animal reproduction studies, TRACLEER may cause fetal harm, including birth defects and fetal death, when administered to a pregnant female and is contraindicated during pregnancy [see Contraindications (4.1) ] . Available data from postmarketing reports and published literature over decades of use with endothelin receptor antagonists (ERA) in the same class as TRACLEER 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. In animal reproduction studies, oral administration of bosentan to pregnant rats at 2-times the maximum recommended human dose (MRHD) on a mg/m 2 basis caused teratogenic effects in rats, including malformations of the head, mouth, face, and large blood vessels [see Animal Data ] . Advise pregnant women of the potential risk to a fetus. 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 2–4% and 15–20%, respectively. Data Animal Data Bosentan was teratogenic in rats given oral doses two times the MRHD (on a mg/m 2 basis). In an embryo-fetal toxicity study in rats, bosentan showed dose-dependent teratogenic effects, including malformations of the head, mouth, face and large blood vessels. Bosentan increased stillbirths and pup mortality at oral doses 2 and 10 times the MRHD (on a mg/m 2 basis). Although birth defects were not observed in...

Overdosage

10 OVERDOSAGE Bosentan has been given as a single dose of up to 2400 mg in normal volunteers, or up to 2000 mg/day for 2 months in patients, without any major clinical consequences. The most common side effect was headache of mild to moderate intensity. In the cyclosporine A interaction study, in which doses of 500 and 1000 mg twice daily of bosentan were given concomitantly with cyclosporine A, trough plasma concentrations of bosentan increased 30-fold, resulting in severe headache, nausea, and vomiting, but no serious adverse events. Mild decreases in blood pressure and increases in heart rate were observed. In the postmarketing period, there was one reported overdose of 10,000 mg of TRACLEER taken by an adolescent male patient. He had symptoms of nausea, vomiting, hypotension, dizziness, sweating, and blurred vision. He recovered within 24 hours with blood pressure support. Bosentan is unlikely to be effectively removed by dialysis due to the high molecular weight and extensive plasma protein binding.

How Supplied

16 HOW SUPPLIED/STORAGE AND HANDLING 62.5 mg film-coated, round, biconvex, orange-white tablets, debossed with identification marking "62,5", packaged in a white high-density polyethylene bottle and a white polypropylene child-resistant cap or in foil blister-strips for hospital unit-dosing. NDC 66215-101-06: Bottle containing 60 tablets. NDC 66215-101-03: Carton of 30 tablets in 10 blister strips of 3 tablets. 125 mg film-coated, oval, biconvex, orange-white tablets, debossed with identification marking "125", packaged in a white high-density polyethylene bottle and a white polypropylene child-resistant cap or in foil blister-strips for hospital unit-dosing. NDC 66215-102-06: Bottle containing 60 tablets. NDC 66215-102-03: Carton of 30 tablets in 10 blister strips of 3 tablets. 32 mg tablets for oral suspension, pale yellow to off-white, round, bisected on one side and debossed with identification marking "32" on the other side, packaged in child-resistant Aluminum/Aluminum peel-push blisters. NDC 66215-232-56: Carton of 56 tablets for oral suspension in 4 blister-strips of 14 tablets. NDC 66215-232-14: Blister strip of 14 tablets for oral suspension. Store at 20 ºC to 25 ºC (68 ºF to 77 ºF). Excursions are permitted between 15 °C and 30 °C (59 °F and 86 °F). [See USP Controlled Room Temperature]. These storage temperatures apply to both film-coated and dispersible tablets. Divided dispersible tablets should be stored under the same conditions and used within 7 days. Tablet pieces may be returned to the opened blister and stored there out of reach of children for up to 7 days. Keep out of reach of children.

About This Information

This drug information is sourced from FDA-approved labeling via the openFDA database. It is intended for educational and reference purposes only. This is not medical advice. Always consult your healthcare provider before making decisions about medication. Drug information may be updated by the FDA; check with your pharmacist for the most current information.

What are side effects?

Side effects are unwanted reactions that can occur when taking a medication. They range from mild (headache, nausea) to severe (allergic reactions, organ damage). Not everyone experiences side effects, and severity varies. Report any concerning side effects to your doctor.

What are drug interactions?

Drug interactions occur when a medication is affected by another drug, food, or supplement. Interactions can make medications less effective or cause dangerous side effects. Always tell your doctor about all medications and supplements you take.