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Registry Hub
Antineoplastic Agent/Discontinued

FLUDARA

FLUDARA

Clinical safety rating

caution

Comprehensive clinical and safety monograph for FLUDARA (FLUDARA).


What is FLUDARA?

Comprehensive clinical and safety monograph for FLUDARA (FLUDARA).

Indications & Uses

B-cell chronic lymphocytic leukemia (CLL) in adults who have not responded to or have progressed during treatment with at least one standard alkylating-agent regimenOff-label: non-Hodgkin lymphoma, acute myeloid leukemia, conditioning for hematopoietic stem cell transplantation

Side Effects

Increased risk of infection, Vomiting, Weakness, Nausea, Fatigue, Fever, Decreased blood cells (red cells, white cells, and platelets), Diarrhea, Cough

Compare FLUDARA vs AGRYLIN →View all Antineoplastic Agent drugs →

Mechanism of Action

Fludarabine is a purine nucleotide analog that inhibits DNA synthesis by interfering with ribonucleotide reductase and DNA polymerase, leading to cell death in dividing lymphocytes.

What the body does with it

MetabolismFludarabine is dephosphorylated in serum to 9-β-D-arabinofuranosyl-2-fluoroadenine (F-ara-A), which is then phosphorylated intracellularly to active triphosphate (F-ara-ATP). Further metabolism involves deamination by adenosine deaminase, but the primary route is renal excretion of unchanged drug and metabolites.
ExcretionRenal: 60% excreted unchanged in urine; biliary/fecal: <5% as metabolites.
Half-lifeFludarabine phosphate: 0.7-1 h (rapid dephosphorylation). Active metabolite 2-fluoro-ara-A: terminal t1/2 20-30 h (up to 40 h in renal impairment).
Protein bindingFludarabine: 19-29% (primarily albumin); 2-fluoro-ara-A: minimal binding.
Volume of DistributionVd: 2.4 L/kg (fludarabine); 0.5-0.9 L/kg (2-fluoro-ara-A, approximating total body water).
BioavailabilityOral: 55-75% under fasting conditions; food reduces Cmax but not AUC.
Onset of ActionIV: Onset 2-3 days for reduction in lymphocyte count; maximal effect after 1-2 cycles.
Duration of ActionDuration of immunosuppression: 6-12 months after therapy; myelosuppression may persist ≥4 weeks.
Molecular Weight285.23

Classification & Brands

Action ClassAntimetabolites
Brand SubstitutesFludaphos 50mg Injection, Fludarither 50 Injection, Fludacel 50mg Injection, Naprobin 50mg Injection, Fludocyte 50mg Injection, Lymfuda 10mg Tablet, Fludabine 10mg Tablet

Dosing & administration

25 mg/m^2 intravenously over 30 minutes daily for 5 consecutive days every 28 days.

Dosage formINJECTABLE
Renal impairmentCrCl 30-70 mL/min: reduce dose by 20%. CrCl <30 mL/min: contraindicated.
Liver impairmentNo specific recommendations for hepatic impairment; use with caution in severe hepatic impairment (Child-Pugh C).
Pediatric useNot established for pediatric patients; safety and efficacy not determined.
Geriatric useNo specific adjustment; monitor renal function and hematologic parameters closely.

Use during pregnancy

1st trimesterContraindicated due to teratogenicity; avoid pregnancy.
2nd trimesterContraindicated due to risk of fetal harm.
3rd trimesterContraindicated due to risk of neonatal myelosuppression.

Clinical note

Comprehensive clinical and safety monograph for FLUDARA (FLUDARA).

Placental transferCrosses placenta; documented in human studies.
BreastfeedingExcreted into breast milk; potential for serious adverse reactions in nursing infants; discontinue breastfeeding or drug.
Lactation RatingL5 (Contraindicated)
Teratogenic RiskFludarabine is contraindicated in pregnancy. It is a nucleoside analog with known teratogenic and embryotoxic effects. First trimester exposure is associated with major congenital malformations, particularly neural tube defects, craniofacial anomalies, and limb defects. Second and third trimester exposure can cause fetal growth restriction, myelosuppression, and increased risk of fetal death. Both animal studies and human case reports confirm significant fetal harm.
Fetal MonitoringIf inadvertent exposure during pregnancy occurs, serial fetal ultrasounds for structural anomalies, growth parameters, and amniotic fluid volume are recommended. Maternal complete blood counts with differential and platelet count should be monitored weekly due to risk of myelosuppression. Assess for signs of infection or bleeding. Fetal heart rate monitoring may be considered after 24 weeks gestation.
Fertility EffectsFludarabine can cause irreversible gonadal suppression in both sexes. In males, it may lead to azoospermia or oligospermia; in females, ovarian failure and premature menopause have been reported. Fertility preservation options (e.g., sperm or oocyte cryopreservation) should be discussed prior to initiation. Long-term data suggest a dose-dependent effect on reproductive function.

Warnings & precautions

■ FDA Black Box Warning

WARNING: FLUDARA MAY CAUSE SEVERE BONE MARROW SUPPRESSION (ANEMIA, THROMBOCYTOPENIA, NEUTROPENIA) AND MAY INDUCE AUTOIMMUNE HEMOLYTIC ANEMIA. PATIENTS SHOULD BE MONITORED CLOSELY FOR HEMATOLOGIC TOXICITY. NEUROTOXICITY (INCLUDING BLINDNESS, COMA, AND DEATH) HAS BEEN REPORTED, PARTICULARLY AT HIGH DOSES (>40 mg/m2/day).

Side Effect Profile

Serious Effects

Absolute Contraindications

Hypersensitivity to fludarabine or any componentSevere bone marrow suppressionPregnancyBreastfeedingConcurrent use with pentostatin

Clinical Precautions

PrecautionsSevere bone marrow suppression, particularly thrombocytopenia, anemia, and neutropenia, Autoimmune hemolytic anemia, which can be fatal, Neurotoxicity, especially at high doses; monitor for altered mental status, visual disturbances, seizures, Tumor lysis syndrome, especially in patients with high tumor burden, Immunosuppression and increased risk of opportunistic infections, Pulmonary toxicity including interstitial pneumonitis, Hepatotoxicity and increased liver enzymes, Use with caution in renal impairment; dose adjustment required (CrCl <30 mL/min)
Food/DietaryNo specific dietary restrictions. Maintain adequate hydration. Grapefruit juice may interact; avoid excessive consumption. Avoid alcohol due to possible hepatotoxicity.

Clinical Tips & Counseling

Clinical PearlsFludarabine is a purine analog used in B-cell chronic lymphocytic leukemia (CLL). It requires dose adjustment in renal impairment (CrCl <30 mL/min). Myelosuppression is dose-limiting; monitor blood counts. Use with caution in patients with prior autoimmune hemolytic anemia. Trimethoprim-sulfamethoxazole should be given for Pneumocystis jirovecii prophylaxis. Allopurinol is recommended for tumor lysis syndrome prevention. Administer IV over 30 minutes or longer.
Patient AdviceTake this medication exactly as prescribed by your doctor. · You will need regular blood tests to monitor your blood cell counts. · Avoid live vaccines during treatment and for 12 months after. · Report any signs of infection (fever, chills, sore throat) or unusual bleeding/bruising immediately. · Use effective contraception during treatment and for at least 6 months after the last dose. · Drink plenty of fluids to help prevent kidney problems. · Avoid exposure to people with infections.

FLUDARA Interactions

Loading safety data…

This overview is compiled from peer-reviewed clinical sources and FDA labeling. It's here to support — not replace — clinical judgment. Always verify dosing against your institution's current protocols before prescribing.

On this page

Mechanism of ActionDosing & administrationUse during pregnancyWarnings & precautionsDrug interactions

Compare with

AGRYLINAURLUMYNCLADRIBINECLOFARABINECLOLAR

External sources

DailyMed (NIH) PubMed OpenFDA