Randomized Double-Blind Phase II Trial of Baby Exemestane Versus Baby Tamoxifen in Post-Menopausal Women at High Risk for Breast Cancer

The goal of this research study is to evaluate the efficacy and safety of low-dose exemestane versus low-dose tamoxifen in post-menopausal women at high risk for breast cancer. The names of the study drugs involved in this study are: * Exemestane (a type of steroidal aromatase inhibitor) * Tamoxifen (a type of selective estrogen receptor modulator)

NCT Number	NCT07499999
Lead Sponsor	Dana-Farber Cancer Institute Collaborators: Breast Cancer Research Foundation
Conditions	Breast Cancer, Ductal Carcinoma, Estrogen-receptor-positive Breast Cancer, Atypical Lobular Hyperplasia, BRCA2 Mutation, CHEK2 Gene Mutation, Ataxia Telangiectasia Mutated Gene Mutation
Enrollment	140 participants
Start Date	2026-09-09
Primary Completion	2027-08-31 (estimated)
Study Completion	2028-08-31 (estimated)
Updated on ClinicalTrials.gov	2026-03-30