BRCA-P Trial of Denosumab to Prevent Breast Cancer in Women With a BRCA1 Mutation
Trial details
Overview: Some early studies suggest that denosumab may reduce the risk of breast cancer in women with a BRCA1 mutation. The researchers are doing this larger study to provide more definite information.
Phase: Phase III; Phase III trials compare the safety and effectiveness of a new treatment to the current standard of care. Phase III trials are usually large — some involve thousands of people — and are done at many places in the United States and around the world.
Number of people to enroll: This trial is active, but is no longer recruiting participants.
ClinicalTrials.gov ID number: NCT04711109
Sponsor of the trial: Alliance for Clinical Trials in Oncology
Who is the trial for?
The study is enrolling women between the ages of 25 and 55 who know they have a BRCA1 mutation and have never been diagnosed with breast cancer.
Why is the trial being done?
The trial is designed to see if denosumab every six months for five years can prevent both invasive breast cancer and DCIS in women who have a BRCA1 mutation. The women in the study will be followed for five years.
Women with a BRCA1 mutation have a much higher-than-average risk of breast cancer. About 13% of women in the general population in the United States will develop breast cancer sometime during their lives. But according to the National Cancer Institute, 55% to 72% of women with a BRCA1 mutation will develop breast cancer by age 80.
Under the brand name Prolia, denosumab is used to treat osteoporosis and increase bone density in both women and men.
Under the brand name Xgeva, denosumab is used to help ease bone pain and prevent broken bones in people diagnosed with metastatic breast cancer that has spread to the bones.
Denosumab is a RANKL inhibitor. The medicine works by blocking the signals to the cells that break down bone. Some early research in mice suggests that the RANKL pathway and RANKL protein play important roles in BRCA1-mutated breast cancer.
The researchers are doing this study to see if the mouse results could be the same in people.
Specific eligibility requirements
Women are eligible for this study if they:
have a BRCA1 mutation
are ages 25 to 55
have no evidence of breast cancer in the six months before joining the study
have no evidence of ovarian cancer when joining the study
are not pregnant
are not planning to have risk-reducing prophylactic mastectomy
Women are not eligible for the study if they:
have had a double mastectomy
have a history of ovarian cancer
have a history of breast cancer
have a history of other invasive cancer, except for basal cell or squamous cell skin cancer
are pregnant
have low calcium levels
Read more about the eligibility requirements.
Denosumab side effects
The most common side effects of denosumab are:
low calcium levels
atypical femur fracture (stress fracture of the thigh bone)
Study locations
The study is taking place at various locations around the United States.
For a complete list of sites, visit: https://clinicaltrials.gov/study/NCT04711109#contacts-and-locations
For more information or to enroll
Call Dr. Judy Garber at 617-632-5961 or email her at judy_garber@dfci.harvard.edu
— Last updated on September 12, 2025 at 2:46 PM