Clinical Research Directory

Inclusion Criteria: * Patients with ER positive HER2 negative metastatic breast cancer, harboring an activating PIK3CA mutation, scheduled to start treatment with Alpelisib and fulvestrant. * Ages 18 - 85 * ECOG performance status 0, 1 or 2 * Ability to understand and willingness to sign a written informed consent. Exclusion Criteria: * Impairment of gastrointestinal (GI) function or GI disease that may significantly alter the absorption of Alpelisib * Uncontrolled diabetes mellitus, defined as HbA1c above 8% * Diabetes mellitus controlled by insulin * Uncontrolled intercurrent illness including, but not limited to: active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements * Pregnancy * Known allergy to pioglitazone