Letrozole

Research records

Historical source snapshot. Not freshly verified, not a recommendation. Study findings, community accounts and app defaults are not interchangeable.

Publication suitability · 2026-10-15: Historical reference only; not a clinical verification. Clinical, regulatory, efficacy, safety and dose claims are not independently established by this review.

Letrozole

An FDA-approved aromatase inhibitor used to treat hormone receptor-positive breast cancer.

Evidence category: Regulator / guideline. This describes the source category, not approval or certainty.

Regulatory statement in source: FDA-approved.

Letrozole is an aromatase inhibitor approved by the FDA in 1997 for treatment of advanced breast cancer in postmenopausal women and approved in 1998 following prior antiestrogen failure. It blocks aromatase enzyme activity, lowering estrogen levels. FDA approvals include adjuvant and extended adjuvant treatment of early breast cancer and first/second-line treatment of advanced disease.

Benefits reported in the imported source

• Adjuvant treatment of early breast cancer in postmenopausal women.
• Extended adjuvant treatment after 5 years of tamoxifen.
• First/second-line treatment of advanced breast cancer

Risks and limits

• Lipid changes
• Bone loss and increased fracture risk
• Arthralgia
• Hypercholesterolemia

Source bottom line: FDA-approved aromatase inhibitor for hormone receptor-positive breast cancer with established efficacy.

Uncertainty: Reference information only. Not medical advice.

Study protocols — reports, not instructions

No study protocol recorded in this snapshot. This does not establish that no study exists.

Community and practice descriptions

Accounts of a practice are not evidence of safety or effectiveness. Words such as “standard”, “safe” or “recommended” describe the source account, not verified consensus or this wiki’s advice. Commercial and self-published citations are retained for traceability, not vendor endorsement or independent clinical corroboration.

No community description recorded. This entry has no final B-82 outcome record; it is not a researched-empty finding.

Pharmacokinetic context

Historical half-life estimate: 48 hours. FDA label, Femara: terminal elimination half-life about 2 days Population/route context and estimates may differ. This is not a schedule or a verified human dosing rule.

Source references

• DailyMed: letrozole
• FDA Approves Femara as First-Line Therapy
• Letrozole in Breast Cancer Treatment - PubMed