Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
CLOLAR vs ELLENCE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Clolar (clofarabine) is a purine nucleoside antimetabolite that inhibits DNA synthesis and RNA transcription. It is phosphorylated intracellularly to its active triphosphate form, which competes with adenosine triphosphate for incorporation into DNA, leading to chain termination and inhibition of DNA polymerase and ribonucleotide reductase, resulting in apoptosis.
ELLENCE (epirubicin) is an anthracycline cytotoxic antibiotic. It intercalates between DNA base pairs, inhibits topoisomerase II activity, and generates free radicals, leading to DNA damage and cell death.
FDA: Treatment of relapsed or refractory acute lymphoblastic leukemia (ALL) in pediatric patients aged 1 to 21 years.,Off-label: Treatment of acute myeloid leukemia (AML), myelodysplastic syndromes (MDS), chronic myeloid leukemia (CML) in blast crisis.
Adjuvant therapy in patients with axillary node-positive breast cancer,Treatment of metastatic breast cancer,Off-label: treatment of ovarian cancer, gastric cancer, small cell lung cancer, and soft tissue sarcoma
5 mg/m2 intravenously over 2 hours daily for 5 consecutive days. Repeat every 28 days.
60-120 mg/m2 IV bolus or slow infusion on Day 1 every 21-28 days; or 20-30 mg/m2 IV daily for 3 days repeated every 28 days.
Terminal elimination half-life approximately 5.2 hours in patients with normal renal function; prolonged in renal impairment (up to 9.8 hours with Cr Cl <60 m L/min) and in elderly; clinical context: supports once-daily dosing adjustment for renal function.
Terminal elimination half-life is approximately 20-40 hours (mean ~30 hours). This supports a 3-week dosing interval to allow for recovery from myelosuppression.
Clofarabine is partially metabolized by deamination via cytidine deaminase (CDA) to inactive 6-keto-clofarabine. Approximately 50-60% of the drug is excreted unchanged in urine.
Primarily hepatic metabolism via aldoketoreductases and conjugation; also metabolized by glucuronidation and cytochrome P450 (CYP) enzymes, including CYP2B4 and CYP3A4.
Renal: 50-60% as unchanged drug; biliary/fecal: minimal (<5%)
Primarily hepatobiliary excretion: ~40-50% of dose excreted as unchanged drug and metabolites in bile and feces. Renal excretion accounts for <10% (mostly as metabolites).
47% bound to human plasma proteins, primarily albumin.
Approximately 77% bound to plasma proteins, primarily albumin.
Central Vd approximately 172 L/m² (extensive tissue distribution); in L/kg: ~4.6 L/kg (assuming 70 kg patient with BSA 1.73 m²). Clinical meaning: indicates wide distribution into total body water and tissues, exceeding total body water.
Mean volume of distribution is 13-34 L/kg (average ~21 L/kg), indicating extensive tissue distribution and binding.
Intravenous: 100% (only route of administration); oral: not available (no oral formulation).
IV only; oral bioavailability is negligible (<5%) due to extensive first-pass metabolism. Not administered orally.
Cr Cl >= 60 m L/min: no adjustment. Cr Cl 30-59 m L/min: reduce dose by 20%. Cr Cl < 30 m L/min: contraindicated.
No specific GFR-based dose adjustments required; caution in severe renal impairment (Cr Cl <10 m L/min) with potential increased toxicity.
No specific guidelines; use caution in severe hepatic impairment (Child-Pugh class C) and consider dose reduction based on tolerability.
Child-Pugh A: reduce dose by 25%; Child-Pugh B: reduce dose by 50%; Child-Pugh C: contraindicated or use at 50% reduction with caution.
1-21 years: 5 mg/m2 IV over 2 hours daily for 5 days every 28 days; reduce dose by 50% in patients with renal impairment.
75-100 mg/m2 IV on Day 1 of 21-day cycles or 20-30 mg/m2 IV daily for 3 days every 28 days.
No specific dose adjustment, but monitor renal function closely due to age-related decline and increased risk of toxicity.
No specific dose adjustment; consider increased susceptibility to myelosuppression and cardiotoxicity; monitor left ventricular ejection fraction.
WARNING: HEMATOLOGIC TOXICITY, INFECTION, AND HEPATIC TOXICITY. Clolar suppresses bone marrow function, causing severe neutropenia, thrombocytopenia, and anemia. Fatal infections have occurred. Hepatic toxicity, including hepatic failure and death, has been reported. Monitor blood counts and liver function frequently.
Myocardial toxicity, including potentially fatal congestive heart failure, especially with cumulative doses >900 mg/m²; secondary acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS); extravasation leading to severe tissue necrosis; severe myelosuppression.
Bone marrow suppression: severe neutropenia, thrombocytopenia, and anemia require close monitoring. Infections: serious and fatal infections (bacterial, fungal, viral) may occur. Hepatic toxicity: elevation of liver enzymes, bilirubin, and hepatic veno-occlusive disease. Renal toxicity: increased creatinine, hematuria, and hemolytic uremic syndrome-like reactions. Cardiac toxicity: pericardial effusion, hypotension, and ventricular dysfunction. Tumor lysis syndrome. Hypersensitivity reactions. Use in pregnancy: embryo-fetal toxicity. Vaccination: avoid live vaccines.
Cardiotoxicity (cumulative dose-dependent), myelosuppression, secondary leukemia, extravasation, hepatotoxicity, renal impairment, immunosuppression, tumor lysis syndrome, and fetal harm.
Absolute: Hypersensitivity to clofarabine or any component of the formulation. Relative: Severe hepatic impairment (bilirubin >3 mg/d L or transaminases >5x ULN). Severe renal impairment (creatinine clearance <30 m L/min).
Severe hepatic impairment (Child-Pugh class C), severe renal impairment (Cr Cl <30 m L/min), baseline neutrophil count <1500 cells/mm³, severe cardiac dysfunction, hypersensitivity to epirubicin or other anthracyclines.
No specific food interactions are documented. However, maintain adequate hydration to reduce risk of nephrotoxicity and tumor lysis syndrome. Avoid grapefruit and grapefruit juice as they may affect metabolism via CYP3A4 (theoretical concern, though clofarabine is primarily renally excreted).
Avoid grapefruit and grapefruit juice during treatment as they may affect drug metabolism. No other specific food interactions known.
Clofarabine is contraindicated in pregnancy. Based on its mechanism of action (inhibitor of DNA synthesis) and animal studies, there is a high risk of fetal harm if administered during pregnancy. In the first trimester, there is a significant risk of embryolethality and teratogenicity (structural anomalies). In the second and third trimesters, fetal growth restriction and central nervous system damage may occur. Pregnancy must be excluded before initiation.
Pregnancy Category D. First trimester: High risk of teratogenicity including cardiac anomalies, skeletal defects, and fetal demise. Second and third trimesters: Risk of fetal growth restriction, preterm birth, and neonatal myelosuppression. Avoid use unless absolutely necessary.
No data available on the excretion of clofarabine into breast milk or its effects on the nursing infant. Due to potential for serious adverse reactions (e.g., myelosuppression, gastrointestinal toxicity), breastfeeding is contraindicated during therapy and for at least 3 months after the last dose. M/P ratio is unknown.
Contraindicated due to potential transfer into breast milk (M/P ratio not available). Theoretical risk of severe adverse effects in infants including bone marrow suppression and cardiotoxicity. Discontinue nursing or drug.
There are no established dose adjustments for clofarabine during pregnancy, as use is contraindicated. Physiological changes in pregnancy (e.g., increased plasma volume, altered renal clearance) may affect pharmacokinetics, but no dosing guidelines exist. If inadvertent exposure occurs, immediate discontinuation is recommended and the pregnancy should be managed by a maternal-fetal medicine specialist.
No established dose adjustments; avoid use if possible. Pharmacokinetic changes include increased volume of distribution and clearance, but insufficient data to recommend dose modification. Use reduced doses if unavoidable, guided by toxicity monitoring.
Clolar (clofarabine) is a purine nucleoside analog indicated for pediatric relapsed/refractory acute lymphoblastic leukemia. Key pearls: (1) Monitor for systemic inflammatory response syndrome (SIRS) and capillary leak syndrome; premedicate with corticosteroids. (2) Requires aggressive hydration and allopurinol for tumor lysis prophylaxis. (3) Dose reductions needed for renal impairment (Cr Cl < 60 m L/min). (4) Avoid live vaccines during and after treatment.
Ellence (epirubicin) is an anthracycline chemotherapeutic agent. It is a vesicant; extravasation can cause severe tissue necrosis. Administer via a freely flowing IV line. Premedicate with antiemetics. Monitor for cardiotoxicity, which is dose-dependent and may be cumulative. Total lifetime dose should not exceed 900-1000 mg/m². Assess cardiac function (LVEF) before and during treatment. Urine may turn red for 1-2 days after administration. Avoid live vaccines.
Clolar is a chemotherapy drug used to treat a type of leukemia in children that has not responded to other treatments.,You may experience side effects like fever, nausea, vomiting, diarrhea, and skin rashes. Report any signs of infection or unusual bleeding.,Drink plenty of fluids as directed to prevent kidney problems. You may receive IV fluids before and after treatment.,Avoid vaccinations without doctor approval, as live vaccines are not safe during treatment.,This drug can cause severe reactions including organ inflammation and fluid retention; seek immediate medical help if you have difficulty breathing, rapid weight gain, or swelling.
Ellence can cause severe nausea and vomiting; take antiemetics as prescribed.,Report any pain, redness, or swelling at the injection site immediately.,Urine may appear red for 1-2 days after treatment; this is normal.,Use effective contraception during and for at least 6 months after treatment.,Avoid live vaccines (e.g., MMR, varicella) while on this medication.,Report signs of infection (fever, chills), unusual bleeding or bruising, shortness of breath, or chest pain.,Do not breastfeed while taking Ellence.
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 CLOLAR vs ELLENCE, answered by our medical review team.
CLOLAR is a Antineoplastic Agent that works by Clolar (clofarabine) is a purine nucleoside antimetabolite that inhibits DNA synthesis and RNA transcription. It is phosphorylated intracellularly to its active triphosphate form, which competes with adenosine triphosphate for incorporation into DNA, leading to chain termination and inhibition of DNA polymerase and ribonucleotide reductase, resulting in apoptosis.. ELLENCE is a Anthracycline Antineoplastic that works by ELLENCE (epirubicin) is an anthracycline cytotoxic antibiotic. It intercalates between DNA base pairs, inhibits topoisomerase II activity, and generates free radicals, leading to DNA damage and cell death.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between CLOLAR and ELLENCE 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 CLOLAR is: 5 mg/m2 intravenously over 2 hours daily for 5 consecutive days. Repeat every 28 days.. The standard adult dose of ELLENCE is: 60-120 mg/m2 IV bolus or slow infusion on Day 1 every 21-28 days; or 20-30 mg/m2 IV daily for 3 days repeated every 28 days.. 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 CLOLAR and ELLENCE 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. CLOLAR is classified as Category C. Clofarabine is contraindicated in pregnancy. Based on its mechanism of action (inhibitor of DNA synthesis) and animal studies, there is a high risk of fetal harm if administered du. ELLENCE is classified as Category C. Pregnancy Category D. First trimester: High risk of teratogenicity including cardiac anomalies, skeletal defects, and fetal demise. Second and third trimesters: Risk of fetal growt. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.