Comparative Pharmacology
Head-to-head clinical analysis: ADRUCIL versus METHOTREXATE LPF.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ADRUCIL versus METHOTREXATE LPF.
ADRUCIL vs METHOTREXATE LPF
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Fluorouracil (5-FU) is a pyrimidine analog that inhibits thymidylate synthase, interfering with DNA synthesis. It is metabolized to its active metabolites, which incorporate into RNA and DNA, causing cytotoxicity primarily in S-phase cells.
Methotrexate is a folate analog that inhibits dihydrofolate reductase (DHFR), blocking the synthesis of tetrahydrofolate and subsequently thymidylate and purine synthesis. This inhibits DNA synthesis, repair, and cellular replication. In low-dose regimens, it has anti-inflammatory and immunomodulatory effects through adenosine release and inhibition of cytokine production.
12 mg/kg IV bolus daily for 4 days, then if no toxicity, 6 mg/kg IV on days 6, 8, 10, and 12; or 15 mg/kg IV weekly; or 500-600 mg/m2 IV every 3-4 weeks.
7.5 to 25 mg orally once weekly for rheumatoid arthritis; for psoriasis, 10 to 25 mg orally once weekly. Intravenous dosing varies by indication; for high-dose methotrexate (e.g., osteosarcoma), 8 to 12 g/m² IV over 4 hours.
None Documented
None Documented
Biphasic elimination: initial t1/2α ~10-20 minutes, terminal t1/2β ~20-24 hours. Accumulation occurs with continuous infusion.
Terminal half-life 3-10 hours for low doses, 8-15 hours for high doses; prolonged to 12-24 hours in renal impairment due to delayed clearance.
Primarily hepatic metabolism; renal excretion of metabolites accounts for ~60-80% of the dose. Unchanged fluorouracil excreted renally is <10%. Fecal excretion is minimal (<5%).
Primarily renal (80-90% unchanged via glomerular filtration and active tubular secretion); small amount biliary/fecal (<10%).
Category C
Category D/X
Antimetabolite
Antimetabolite