A Phase 3 Open-Label Randomized Study Assessing the Efficacy and Safety of RLY-2608 + Fulvestrant Versus Capivasertib + Fulvestrant as Treatment for PIK3CA-mutant Hormone Receptor Positive, Human Epidermal Growth Factor Receptor 2 Negative (HR+/HER2-) Locally Advanced or Metastatic Breast Cancer Following Recurrence or Progression On or After Treatment With a CDK4/6 Inhibitor

This study is comparing two different targeted treatment combinations for people with a specific type of advanced breast cancer that has stopped responding to standard initial therapies. It aims to see if a new drug called RLY-2608 works better or is safer than the current standard treatment, capivasertib, when combined with hormone therapy.

You may be eligible if you have HR+/HER2- breast cancer that has a specific PIK3CA gene mutation and has spread or returned after using CDK4/6 inhibitor treatment. Participants must be adults who are physically active and have not previously taken certain targeted cancer drugs or had issues with high blood sugar.

You will be randomly assigned to receive one of two treatment combinations, both of which include hormone therapy, to see how well they control your cancer. You will be closely monitored by the research team through regular medical scans, blood tests, and check-ups to track your progress and manage any side effects.

This study is currently recruiting patients at various medical centers in Arizona and California. It is a global Phase 3 trial, meaning it is being conducted at multiple locations to confirm the effectiveness of these treatments on a larger scale.