Comparative Pharmacology
Head-to-head clinical analysis: EVISTA versus NOLVADEX.
Peer-Reviewed Evidence
Head-to-head clinical analysis: EVISTA versus NOLVADEX.
EVISTA vs NOLVADEX
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Selective estrogen receptor modulator (SERM) that binds to estrogen receptors, acting as an agonist in bone and antagonist in breast and uterine tissues.
NOLVADEX (tamoxifen citrate) is a nonsteroidal selective estrogen receptor modulator (SERM) that competitively inhibits estrogen binding to estrogen receptors in breast tissue, thereby blocking estrogen-mediated cell proliferation. It also has partial agonist activity in other tissues such as bone and endometrium.
60 mg orally once daily.
20-40 mg orally once daily; for breast cancer, 20 mg/day. For adjuvant therapy, 20 mg/day for 5 years. For ductal carcinoma in situ, 20 mg/day for 5 years. For reduction of breast cancer incidence in high-risk women, 20 mg/day for 5 years.
None Documented
None Documented
Terminal elimination half-life is approximately 32.5 hours (range 27-39 hours) for raloxifene and its glucuronide conjugates; clinically relevant for once-daily dosing.
Tamoxifen: 5-7 days (terminal). N-desmethyltamoxifen (active metabolite): 14 days. Steady-state achieved in 3-4 weeks.
Raloxifene undergoes extensive glucuronidation; <0.1% excreted unchanged in urine. Approximately 95% is excreted in feces over 5 days (primarily as glucuronide conjugates). Renal elimination of unchanged drug is negligible (<0.1%).
Primarily fecal (65%) as conjugates; renal excretion accounts for approximately 25% as metabolites and <0.5% as unchanged drug. Biliary elimination contributes 10%.
Category C
Category C
Selective Estrogen Receptor Modulator
Selective Estrogen Receptor Modulator