A Phase 2, Randomized, Open-Label Dose Optimization and Phase 3, Randomized, Double-Blind, Placebo-Controlled Study of LY4064809 Combined With a CDK4/6 Inhibitor and Endocrine Therapy in Adults With HR+, HER2-Advanced Breast Cancer With a PIK3CA Mutation Who Received No Prior Treatment for Advanced Breast Cancer (PIKALO-2)

This study is testing a new drug called Tersolisib to see if adding it to standard breast cancer treatments helps fight advanced breast cancer more effectively. The goal is to see if this combination therapy can slow down or stop cancer growth for patients who have not yet received treatment for advanced breast cancer.

You may be eligible if you have been diagnosed with advanced hormone-receptor-positive breast cancer that has a specific genetic change called a PIK3CA mutation. Participants must be at least 18 years old and not have certain other conditions like uncontrolled diabetes or specific types of aggressive breast cancer.

You will be randomly assigned to receive either the new experimental medication or a placebo, combined with standard cancer therapies like hormone blockers. You will have regular check-ups with your medical team to monitor your health and see how your cancer is responding to the treatment.

The study is currently recruiting participants at several locations across the United States, including sites in Alaska and Arizona. Please speak with your doctor or the study coordinator to confirm if a location near you is currently enrolling.