Comparative Pharmacology
Head-to-head clinical analysis: ABITREXATE versus CAPECITABINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ABITREXATE versus CAPECITABINE.
ABITREXATE vs CAPECITABINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Methotrexate, the active ingredient, is a folate analog that inhibits dihydrofolate reductase (DHFR), thereby blocking the conversion of dihydrofolate to tetrahydrofolate, inhibiting DNA synthesis, repair, and cellular replication. It also has immunosuppressive and anti-inflammatory effects via modulation of adenosine and cytokine pathways.
Capecitabine is a prodrug that is enzymatically converted to 5-fluorouracil (5-FU) in the body, which inhibits thymidylate synthase and incorporates into RNA and DNA, leading to cytotoxic effects.
7.5 mg orally once weekly; alternatively, 7.5 mg subcutaneously once weekly. Dose may be increased by 2.5 mg every 1-2 weeks up to 20 mg once weekly based on response and tolerability.
Oral, 1250 mg/m2 twice daily for 2 weeks followed by a 1-week rest period.
None Documented
None Documented
Clinical Note
moderateCapecitabine + Digoxin
"Capecitabine may decrease the cardiotoxic activities of Digoxin."
Clinical Note
moderateCapecitabine + Digitoxin
"Capecitabine may decrease the cardiotoxic activities of Digitoxin."
Clinical Note
moderateCapecitabine + Deslanoside
"Capecitabine may decrease the cardiotoxic activities of Deslanoside."
Clinical Note
moderateCapecitabine + Acetyldigitoxin
"Capecitabine may decrease the cardiotoxic activities of Acetyldigitoxin."
Terminal elimination half-life is 6-12 hours (mean 7.5 hours) in patients with normal renal function; prolonged in renal impairment.
The terminal elimination half-life of capecitabine is approximately 0.75 hours. For its active metabolite 5-fluorouracil, the half-life is about 0.7 hours. Clinically, this short half-life necessitates twice-daily dosing to maintain therapeutic levels.
Primarily renal (80-90% as unchanged drug) via glomerular filtration and active tubular secretion; biliary/fecal excretion accounts for <10%.
Capecitabine is predominantly eliminated renally. Approximately 95.5% of the administered dose is recovered in urine, with 61% as unchanged capecitabine and its metabolites. Fecal excretion accounts for about 2.6%. Biliary elimination is minimal (<1%).
Category C
Category D/X
Antimetabolite
Antimetabolite