{"id":"letrozole-or-anastrozole-tablets","safety":{"commonSideEffects":[{"rate":"15-25","effect":"Hot flashes"},{"rate":"15-20","effect":"Arthralgia/joint pain"},{"rate":"10-15","effect":"Fatigue"},{"rate":"8-12","effect":"Headache"},{"rate":"8-10","effect":"Nausea"},{"rate":"null","effect":"Osteoporosis/bone loss"},{"rate":"5-10","effect":"Vaginal dryness"}]},"_chembl":null,"_dailymed":null,"mechanism":{"_ai_source":"claude-haiku-4.5","explanation":"Both drugs inhibit the aromatase enzyme, which catalyzes the final step of estrogen synthesis in postmenopausal women. By depleting circulating estrogen levels, they suppress the growth of estrogen-dependent breast cancer cells. These are non-steroidal aromatase inhibitors commonly used as first-line endocrine therapy for hormone receptor-positive breast cancer.","oneSentence":"Letrozole and Anastrozole are aromatase inhibitors that block the conversion of androgens to estrogen, reducing estrogen levels in postmenopausal women with hormone receptor-positive breast cancer.","_ai_confidence":"high"},"_scrapedAt":"2026-03-28T01:18:42.154Z","_scrapedBy":"cloudflare-swarm","_wikipedia":null,"indications":{"approved":[{"name":"Hormone receptor-positive, HER2-negative breast cancer in postmenopausal women (adjuvant or metastatic)"},{"name":"Extended adjuvant therapy following tamoxifen in postmenopausal women with early-stage breast cancer"}]},"trialDetails":[{"nctId":"NCT06492616","phase":"PHASE3","title":"A Study of Elacestrant Versus Standard Endocrine Therapy in Women and Men With ER+,HER2-, Early Breast Cancer With High Risk of Recurrence","status":"RECRUITING","sponsor":"Stemline Therapeutics, 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