Inavolisib with fulvestrant for treating HR+/HER2-, PIK3CA mutated locally advanced or metastatic breast cancer after CDK4/6i and endocrine combination therapy

Inavolisib in combination with fulvestrant is in development for the treatment of patients with hormone receptor positive (HR+), human epidermal growth factor receptor 2 negative (HER2-), PIK3CA-mutated locally advanced or metastatic breast cancer. Locally advanced means that the cancer has spread close to where it started and metastatic means it has spread around the body. Breast cancer occurs when abnormal cells in the breast grow and divide in an uncontrolled way forming a growth (tumour). The PIK3CA gene holds the instructions for making p110 alpha, a protein responsible for cell growth, division, movements, and protein production. A mutation in PIK3CA can disrupt this process. People diagnosed with HR+ metastatic breast cancer have a risk of disease progression and treatment side effects, creating a need for additional treatments.