Comparative Pharmacology
Head-to-head clinical analysis: ADRUCIL versus XELODA.
Head-to-head clinical analysis: ADRUCIL versus XELODA.
ADRUCIL vs XELODA
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.
Prodrug of 5-fluorouracil (5-FU), inhibits thymidylate synthase, incorporates into RNA and DNA, leading to cell death.
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.
Capecitabine 1250 mg/m2 orally twice daily for 2 weeks followed by a 1-week rest period, administered as 3-week cycles.
None Documented
None Documented
Biphasic elimination: initial t1/2α ~10-20 minutes, terminal t1/2β ~20-24 hours. Accumulation occurs with continuous infusion.
Capecitabine: 0.65-0.85 h; 5'-DFCR: 0.9-1.1 h; 5'-DFUR: 0.75-1.0 h; 5-FU: 0.75-1.1 h. Terminal half-life of 5-FU is short, requiring continuous dosing for sustained exposure.
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%).
Renal (95.5% as metabolites; 26.1% as parent drug and metabolites, primarily 5'-DFCR, 5'-DFUR, and FBAL); fecal (< 3%)
Category C
Category C
Antimetabolite
Antimetabolite