Gedatolisib Plus Fulvestrant With or Without Palbociclib vs Standard-of-Care for the Treatment of Patients With Advanced or Metastatic HR+/HER2- Breast Cancer (VIKTORIA-1)

Histologically or cytologically confirmed diagnosis of metastatic or locally advanced breast cancer Adult females, pre- and/or post-menopausal, and adult males. Pre-menopausal (and peri-menopausal) women can be enrolled if amenable to treatment with an LHRH agonist. Patients are to have commenced concomitant treatment with LHRH agonist prior to or on Cycle 1, Day 1 and must be willing to continue on it for the duration of the study.Negative pregnancy test for women of childbearing potential. Female subjects of childbearing potential must use an effective and/or acceptable contraceptive method from screening until 1 year after the last dose of study treatment Confirmed diagnosis of estrogen receptor positive and/or progesterone receptor positive, as per American Society of Clinical Oncology/College of American Pathologists (ASCO-CAP) guidelines (2020), based on most recent tumor biopsy utilizing an assay consistent with local standards Documented HER2 immunohistochemistry (IHC) negative as per ASCO-CAP 2018 guidance Adequate archival or fresh tumor tissue for the analysis of PIK3CA mutational status Subject must have documentation of radiological disease progression on or after the last prior treatment and also have radiologically evaluable disease (measurable and/or non-measurable) according to RECIST v1.1, per local assessment. Subjects with bone only disease must have lytic or mixed lytic/blastic lesions that can be accurately assessed; bone only blastic lesions with no soft tissue component is not allowed. Eastern Cooperative Oncology Group (ECOG) performance status of 0-1 Life expectancy of at least 3 months Progressed during or after CDK4/6 inhibitor combination treatment with non-steroidal aromatase inhibitor (AI) Adequate bone marrow, hepatic, renal and coagulation function