Comparative Pharmacology
Head-to-head clinical analysis: FUSILEV versus PROVAYBLUE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: FUSILEV versus PROVAYBLUE.
FUSILEV vs PROVAYBLUE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
FUSILEV (levoleucovorin) is the pharmacologically active isomer of folinic acid. It bypasses dihydrofolate reductase inhibition by dihydrofolate reductase inhibitors (e.g., methotrexate), providing reduced folate that is used in DNA synthesis and repair. It also enhances the efficacy of fluorouracil by stabilizing the ternary complex of thymidylate synthase, thereby inhibiting DNA synthesis.
Methylthioninium chloride (methylene blue) acts by reducing methemoglobin to hemoglobin via the enzyme NADPH methemoglobin reductase, thereby restoring oxygen-carrying capacity of the blood.
Leucovorin (Fusilev) 200 mg/m2 IV over 2 hours, followed by 5-fluorouracil bolus and infusion, repeated every 2 weeks in combination regimens for advanced colorectal cancer.
1-2 mg/kg intravenously over 5 minutes, may repeat once if needed. Maximum single dose: 300 mg.
None Documented
None Documented
The terminal elimination half-life of the active metabolite, 5-methyltetrahydrofolate (5-MTHF), is approximately 6-8 hours in healthy adults; clinically, this supports twice-daily or daily dosing schedules.
Terminal elimination half-life is approximately 10-15 hours. In patients with renal impairment, half-life may be prolonged; no dose adjustment recommended for mild-to-moderate impairment, but use caution in severe impairment.
Primarily hepatic metabolism; renal excretion of metabolites accounts for approximately 40-60% of the dose; fecal excretion is negligible.
Primarily renal excretion as unchanged drug. Approximately 45-60% of a dose is excreted unchanged in urine. Minor fecal elimination accounts for less than 10%.
Category C
Category C
Antidote
Antidote