Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
KATERZIA vs CADUET
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
KATERZIA (bosentan) is an endothelin receptor antagonist (ERA) that blocks endothelin-1 (ET-1) from binding to ETA and ETB receptors in the endothelium and vascular smooth muscle. This inhibits ET-1-mediated vasoconstriction and smooth muscle proliferation, reducing pulmonary vascular resistance and pulmonary arterial pressure.
Amlodipine: Dihydropyridine calcium channel blocker that inhibits calcium ion influx across cardiac and vascular smooth muscle cell membranes, causing vasodilation and reduced peripheral vascular resistance. Atorvastatin: HMG-Co A reductase inhibitor that competitively inhibits the conversion of HMG-Co A to mevalonate, reducing cholesterol synthesis in the liver.
Treatment of pulmonary arterial hypertension (PAH) (WHO Group 1) to improve exercise ability and decrease clinical worsening in patients with WHO class II–IV symptoms,Off-label: Treatment of digital ulcers in systemic sclerosis; prevention of recurrence of digital ulcers; management of inoperable chronic thromboembolic pulmonary hypertension
Hypertension,Coronary artery disease,Hyperlipidemia (as adjunct to diet to reduce elevated total-C, LDL-C, apo B, and TG levels, and to increase HDL-C),Prevention of cardiovascular events in patients with multiple risk factors
5 mg orally once daily for 21 days, then 7 days off, repeated in 28-day cycles.
CADUET (amlodipine/atorvastatin) is available as tablets of 2.5/10, 2.5/20, 2.5/40, 5/10, 5/20, 5/40, 5/80, 10/10, 10/20, 10/40, and 10/80 mg amlodipine/atorvastatin. Initial dose depends on current antihypertensive and lipid-lowering therapy. Usual starting dose is 5/10 mg orally once daily; titrate at intervals of 2-4 weeks based on blood pressure and LDL-C goals. Maximum daily dose: amlodipine 10 mg; atorvastatin 80 mg.
Terminal elimination half-life is approximately 9-12 hours in healthy adults. In patients with hypertension or hepatic impairment, half-life may be prolonged up to 15-20 hours, necessitating dose adjustment.
Amlodipine: terminal half-life 30-50 h (enables once-daily dosing). Atorvastatin: terminal half-life ~14 h, but active metabolites (ortho- and para-hydroxy atorvastatin) have half-life 20-30 h; clinically, pharmacodynamic half-life (HMG-Co A reductase inhibition) is ~20-30 h.
Primarily metabolized by CYP2C9 and CYP3A4 to three major metabolites (Ro 48-5033, Ro 47-8634, Ro 64-1056). Induces CYP2C9 and CYP3A4; also induces CYP2C19.
Amlodipine: Extensively metabolized in the liver via CYP3A4 to inactive metabolites. Atorvastatin: Metabolized in the liver primarily by CYP3A4 to active ortho- and para-hydroxylated metabolites.
Renal elimination accounts for approximately 60-80% of the administered dose, predominantly as unchanged drug via glomerular filtration and active tubular secretion. Biliary/fecal excretion is minimal, <5%.
Amlodipine: 60% renal (metabolites), 20-25% biliary/fecal. Atorvastatin: 1% renal (unchanged), 90% biliary/fecal (≥70% as metabolites).
Approximately 95-98% bound to plasma proteins, primarily albumin and alpha-1-acid glycoprotein. High binding limits tissue distribution and affects free drug concentration.
Amlodipine: ~93% bound to plasma proteins. Atorvastatin: ≥98% bound to plasma proteins (mainly albumin).
Volume of distribution is approximately 0.7-1.2 L/kg (range 50-80 L for a 70 kg adult), indicating moderate tissue distribution beyond plasma volume.
Amlodipine: Vd ~21 L/kg (large, indicating extensive tissue distribution). Atorvastatin: Vd ~6.2 L/kg (moderately large, suggesting distribution into tissues).
Oral bioavailability is approximately 30-40% due to extensive first-pass hepatic metabolism. Food may reduce bioavailability by 20-30%, so dosing should be consistent with respect to meals.
Oral: amlodipine 64-90%; atorvastatin ~14% (low due to first-pass metabolism); food reduces rate but not extent of absorption.
No dose adjustment required for mild to moderate renal impairment (Cr Cl ≥30 m L/min). Not recommended in severe renal impairment (Cr Cl <30 m L/min) or end-stage renal disease.
No dosage adjustment required for mild to moderate renal impairment (Cr Cl ≥30 m L/min). For severe renal impairment (Cr Cl <30 m L/min), use atorvastatin with caution; maximum atorvastatin dose is 20 mg daily. Amlodipine is not dialyzable.
Child-Pugh A: No adjustment. Child-Pugh B: Reduce dose to 5 mg orally once daily for 21 days, then 7 days off. Child-Pugh C: Not recommended.
Contraindicated in active liver disease or unexplained persistent elevations of serum transaminases. For Child-Pugh Class A or B hepatic impairment: atorvastatin dose should be reduced; maximum atorvastatin dose is 20 mg daily. Amlodipine clearance is decreased; initial amlodipine dose should be 2.5 mg daily. No data for Child-Pugh Class C; use contraindicated.
Safety and efficacy not established in pediatric patients.
Not recommended for pediatric patients. Safety and efficacy in children <10 years have not been established. For patients 10-17 years with heterozygous familial hypercholesterolemia, atorvastatin monotherapy is used; CADUET is not indicated.
No specific dose adjustment required; monitor for adverse events due to potential age-related renal and hepatic decline.
Elderly patients (≥65 years) may have increased sensitivity to amlodipine; start at the lower end of dosing range (2.5 mg amlodipine component). Atorvastatin dose adjustment not required based on age alone. Monitor for hypotension and other adverse effects.
WARNING: HEPATOTOXICITY. Bosentan can cause serious hepatic injury, including acute liver failure, requiring baseline and monthly monitoring of liver enzymes. Discontinue if ALT/AST >3x ULN accompanied by symptoms or bilirubin >2x ULN.
HMG-Co A reductase inhibitors (statins) can cause fetal harm; use in pregnant women is contraindicated. Caduet contains atorvastatin; therefore, it is contraindicated in pregnant women.
Hepatotoxicity (monitor LFTs monthly), hepatorenal syndrome; peripheral edema; fluid retention; may cause hypotension; pulmonary veno-occlusive disease (PVOD) may cause pulmonary edema; decreases hemoglobin and hematocrit (monitor at 1 and 3 months, then every 3 months); decreases sperm count; reduces efficacy of hormonal contraceptives (use alternative contraception); caution in hepatic impairment (Child-Pugh Class A; contraindicated in moderate to severe impairment); caution in elderly; not recommended in patients with severe anemia.
Myopathy/Rhabdomyolysis: Risk increased with higher doses, age >65, renal impairment, hypothyroidism, and concurrent use of CYP3A4 inhibitors or other drugs that cause myopathy.,Hepatic effects: Elevated liver enzymes; perform liver function tests before initiation and as clinically indicated.,Fetal toxicity: May cause fetal harm; advise females of reproductive age to use effective contraception.,Peripheral edema: More common with higher doses of amlodipine, especially in females.,Hypotension: In patients with severe aortic stenosis.
Absolute: Hypersensitivity to bosentan or any component; moderate to severe hepatic impairment (Child-Pugh Class B or C); baseline AST/ALT >3× ULN; concomitant use with cyclosporine A (increases bosentan levels and hepatotoxicity); concomitant use with glyburide (increases risk of liver enzyme elevations); pregnancy (teratogenic in animals – can cause birth defects; must exclude pregnancy before initiation and monthly thereafter).
Active liver disease or unexplained persistent elevations of hepatic transaminases,Pregnancy,Breastfeeding (due to potential for serious adverse reactions in nursing infants),Hypersensitivity to amlodipine, atorvastatin, or any component of the formulation
Take with food to improve tolerability and reduce gastrointestinal adverse effects. Avoid grapefruit juice as it may increase treprostinil exposure. Avoid alcohol as it may exacerbate vasodilation and hypotension.
Avoid grapefruit and grapefruit juice as they increase atorvastatin plasma concentrations and risk of adverse effects. No significant food interactions with amlodipine.
Pregnancy Category C. First trimester: animal studies show fetal toxicity; no adequate human data. Second/third trimester: may cause fetal renal impairment, oligohydramnios, and skull ossification defects due to direct renin-angiotensin system inhibition.
FDA Pregnancy Category X. Amlodipine: No evidence of teratogenicity in animal studies, but limited human data; atorvastatin: contraindicated in pregnancy as HMG-Co A reductase inhibitors are associated with fetal abnormalities, including skeletal and CNS defects. First trimester: Atorvastatin is contraindicated; risk of congenital anomalies. Second/third trimester: Avoid exposure; potential for fetal toxicity. Effective contraception required for women of childbearing potential.
No human data; M/P ratio unknown. Excreted in rat milk. Due to potential risk of hypotension and renal impairment in nursing infants, discontinue drug or breastfeeding, considering importance to mother.
Excreted in human milk: Amlodipine: present in low levels (M/P ratio approximately 1.0); atorvastatin: unknown. Due to potential for serious adverse reactions in nursing infants (e.g., skeletal muscle toxicity from statins), breastfeeding is contraindicated during therapy. Alternative agents preferred.
No specific dose adjustments established for pregnancy. However, due to increased plasma volume, efficacy may be reduced; monitor therapeutic response. Contraindicated in pregnancy; avoid use.
Contraindicated during pregnancy; therefore, no dosing adjustments recommended. Discontinue therapy immediately if pregnancy is suspected or confirmed. Pharmacokinetic changes during pregnancy may alter drug metabolism, but no dose adjustments are justified due to teratogenic risk.
KATERZIA (oral treprostinil) is a prostacyclin analogue used for pulmonary arterial hypertension (PAH). Monitor for prostacyclin-related side effects (headache, nausea, diarrhea, jaw pain, flushing). Dose titration is critical; increase by 0.25 mg BID or 0.125 mg TID every 3-4 days as tolerated. Avoid abrupt discontinuation due to risk of rebound pulmonary hypertension. Use with caution in patients with hepatic impairment; reduce starting dose in moderate impairment.
CADUET is a fixed-dose combination of amlodipine (a calcium channel blocker) and atorvastatin (a statin) used for hypertension and dyslipidemia. Avoid concomitant use with strong CYP3A4 inhibitors (e.g., clarithromycin, itraconazole) due to increased statin exposure and risk of myopathy. Monitor liver enzymes before and during therapy, and for muscle symptoms. Use with caution in patients with severe renal impairment. Avoid grapefruit juice as it increases atorvastatin levels.
Take KATERZIA exactly as prescribed, with food to reduce gastrointestinal side effects.,Do not stop taking this medication suddenly; consult your doctor before making any changes.,Common side effects include headache, nausea, diarrhea, jaw pain, and flushing; report severe or persistent symptoms.,Avoid alcohol and grapefruit juice as they may interact with the medication.,Store tablets in the original container at room temperature, away from moisture and light.,If you miss a dose, skip it and take the next dose at the scheduled time; do not double dose.,Inform your healthcare provider of all medications you are taking, especially antihypertensives, anticoagulants, and NSAIDs.
Take this medication once daily at the same time, with or without food.,Avoid grapefruit and grapefruit juice while taking this medication.,Report unexplained muscle pain, tenderness, or weakness, especially if accompanied by fever or malaise.,Notify your doctor if you become pregnant, plan to become pregnant, or are breastfeeding.,Do not stop taking this medication without consulting your doctor, even if you feel well.
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about KATERZIA vs CADUET, answered by our medical review team.
KATERZIA is a Calcium Channel Blocker that works by KATERZIA (bosentan) is an endothelin receptor antagonist (ERA) that blocks endothelin-1 (ET-1) from binding to ETA and ETB receptors in the endothelium and vascular smooth muscle. This inhibits ET-1-mediated vasoconstriction and smooth muscle proliferation, reducing pulmonary vascular resistance and pulmonary arterial pressure.. CADUET is a Calcium Channel Blocker + HMG-CoA Reductase Inhibitor that works by Amlodipine: Dihydropyridine calcium channel blocker that inhibits calcium ion influx across cardiac and vascular smooth muscle cell membranes, causing vasodilation and reduced peripheral vascular resistance. Atorvastatin: HMG-Co A reductase inhibitor that competitively inhibits the conversion of HMG-Co A to mevalonate, reducing cholesterol synthesis in the liver.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between KATERZIA and CADUET depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of KATERZIA is: 5 mg orally once daily for 21 days, then 7 days off, repeated in 28-day cycles.. The standard adult dose of CADUET is: CADUET (amlodipine/atorvastatin) is available as tablets of 2.5/10, 2.5/20, 2.5/40, 5/10, 5/20, 5/40, 5/80, 10/10, 10/20, 10/40, and 10/80 mg amlodipine/atorvastatin. Initial dose depends on current antihypertensive and lipid-lowering therapy. Usual starting dose is 5/10 mg orally once daily; titrate at intervals of 2-4 weeks based on blood pressure and LDL-C goals. Maximum daily dose: amlodipine 10 mg; atorvastatin 80 mg.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between KATERZIA and CADUET in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. KATERZIA is classified as Category C. Pregnancy Category C. First trimester: animal studies show fetal toxicity; no adequate human data. Second/third trimester: may cause fetal renal impairment, oligohydramnios, and sk. CADUET is classified as Category C. FDA Pregnancy Category X. Amlodipine: No evidence of teratogenicity in animal studies, but limited human data; atorvastatin: contraindicated in pregnancy as HMG-CoA reductase inhib. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.