Study of Letrozole With or Without BYL719 or Buparlisib, for the Neoadjuvant Treatment of Postmenopausal Women


About this study

The purpose of the study is to determine whether treatment with a PI3K inhibitor plus letrozole leads to an increase in pathologic clinical response and Objective Response Rate compared to treatment with placebo plus letrozole in patients with Breast cancer

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

  1. Patient is an adult, female ≥ 18 years old at the time of informed consent
  2. Patient has a histologically and/or cytologically confirmed diagnosis of breast cancer
  3. Patient is postmenopausal.
  4. Patient has T1c-T3, any N, M0, operable breast cancer
  5. Patients must have measurable disease
  6. Patient has diagnostic biopsy available for the analysis of PIK3CA mutation and Ki67 level.
  7. Patient has estrogen-receptor and/or progesterone positive breast cancer as per local laboratory testing
  8. Patient has HER2 negative breast cancer defined as a negative in situ hybridization test or an IHC status of 0 or 1+ as per local laboratory testing

Exclusion Criteria:

  1. Patient has locally recurrent or metastatic disease
  2. Patient has received any systemic therapy (e.g. chemotherapy, targeted therapy, immunotherapy) or radiotherapy for current breast cancer disease before randomization.
  3. Patient with type 1 diabetes mellitus or not adequately controlled type 2 diabetes mellitus
  4. History of acute pancreatitis within 1 year of study entry
  5. Uncontrolled hypertension
  6. Other protocol-defined inclusion/exclusion criteria may apply

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Minetta Liu, M.D.

Closed for enrollment

Contact information:

Research Information Center


More information


Publications are currently not available

Study Results Summary

Not yet available

Supplemental Study Information

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