A Phase 1/2, Open-label, First-in-human Study of the Safety, Tolerability, Pharmacokinetics, and Preliminary Efficacy of ETX-636, a Pan-mutant-selective PI3Kα Inhibitor, as Monotherapy and in Combination With Other Anticancer Therapies in Participants With Advanced Solid Tumors

This study is testing a new experimental drug called ETX-636 to see if it can safely stop or slow down the growth of advanced solid tumors. It is designed for people whose cancer has a specific genetic change called a PIK3CA mutation and hasn't responded to standard treatments.

This trial is for adults with advanced solid tumors, such as breast cancer, that have grown after previous treatments. You must have a confirmed PIK3CA genetic mutation, be generally active, and have healthy heart, liver, and kidney function.

You will receive the experimental drug, either alone or combined with a hormone therapy drug called fulvestrant. Doctors will closely monitor you to find the best dose and to see how your body reacts to the medication.

The study is currently recruiting volunteers at medical centers in Newport Beach and San Francisco, California, as well as New Haven, Connecticut.