Comparative Pharmacology
Head-to-head clinical analysis: ARIMIDEX versus LETROZOLE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ARIMIDEX versus LETROZOLE.
ARIMIDEX vs LETROZOLE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Aromatase inhibitor; inhibits conversion of androgens to estrogens by binding to aromatase enzyme, reducing estrogen levels in tissues.
Letrozole is a nonsteroidal aromatase inhibitor. It inhibits the aromatase enzyme, which converts androgens to estrogens, thereby reducing estrogen levels in postmenopausal women and suppressing estrogen-dependent tumor growth.
1 mg orally once daily
2.5 mg orally once daily
None Documented
None Documented
Terminal elimination half-life ~50 hours (range 30-60 hours); supports once-daily dosing.
Clinical Note
moderateLetrozole + Digoxin
"Letrozole may decrease the cardiotoxic activities of Digoxin."
Clinical Note
moderateLetrozole + Digitoxin
"Letrozole may decrease the cardiotoxic activities of Digitoxin."
Clinical Note
moderateLetrozole + Deslanoside
"Letrozole may decrease the cardiotoxic activities of Deslanoside."
Clinical Note
moderateLetrozole + Acetyldigitoxin
"Letrozole may decrease the cardiotoxic activities of Acetyldigitoxin."
Terminal elimination half-life approximately 45 hours (range 42-52 hours). Steady-state achieved in 2-6 weeks with daily dosing.
Primarily hepatic metabolism via N-dealkylation and glucuronidation; ~80% excreted in feces, <10% unchanged in urine.
Primarily hepatic metabolism (CYP3A4, CYP2A6) with 90% excreted in urine as metabolites (glucuronide conjugates) and 10% in feces. <6% excreted unchanged in urine.
Category C
Category D/X
Aromatase Inhibitor
Aromatase Inhibitor