Comparative Pharmacology
Head-to-head clinical analysis: FASLODEX versus FULVESTRANT.
Peer-Reviewed Evidence
Head-to-head clinical analysis: FASLODEX versus FULVESTRANT.
FASLODEX vs FULVESTRANT
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
FASLODEX (fulvestrant) is an estrogen receptor (ER) antagonist that binds to ERs with high affinity, downregulates ER protein levels, and inhibits estrogen signaling via both AF-1 and AF-2 domains, thereby blocking cell proliferation in ER-positive breast cancer cells.
Selective estrogen receptor downregulator (SERD). Binds to estrogen receptors (ER) with high affinity, downregulates ER expression, and inhibits estrogen-stimulated growth of breast cancer cells.
500 mg intramuscularly on days 1, 15, 29, and then once monthly.
500 mg intramuscularly on days 1, 15, 29, and then once monthly thereafter.
None Documented
None Documented
Terminal elimination half-life is approximately 50 days (range 40–60 days) following intramuscular administration, reflecting slow release from the depot and enterohepatic recirculation.
Clinical Note
moderateFulvestrant + Digoxin
"Fulvestrant may decrease the cardiotoxic activities of Digoxin."
Clinical Note
moderateFulvestrant + Digitoxin
"Fulvestrant may decrease the cardiotoxic activities of Digitoxin."
Clinical Note
moderateFulvestrant + Deslanoside
"Fulvestrant may decrease the cardiotoxic activities of Deslanoside."
Clinical Note
moderateFulvestrant + Acetyldigitoxin
"Fulvestrant may decrease the cardiotoxic activities of Acetyldigitoxin."
Terminal elimination half-life ~40 days (range 30–50 days) due to slow release from intramuscular depot; achieves steady-state after ~3–6 months of monthly dosing.
Primarily hepatic metabolism followed by biliary excretion; less than 1% excreted unchanged in urine; fecal elimination accounts for approximately 90% of the administered dose.
Primarily hepatic metabolism via CYP3A4; <1% excreted renally as unchanged drug; ~90% eliminated in feces as metabolites, <1% in urine.
Category C
Category D/X
Estrogen Receptor Antagonist
Estrogen Receptor Antagonist