Can a targeted drug boost hormone therapy against breast cancer?
NCT ID NCT01791478
First seen Aug 19, 2026 · Last updated Aug 19, 2026
Summary
This trial is testing whether adding an experimental drug called BYL719 to standard hormone therapy (letrozole) can better fight hormone receptor-positive metastatic breast cancer in post-menopausal women. BYL719 targets a protein that helps cancer cells grow, while letrozole blocks estrogen, which fuels the cancer. The study aims to find the safest and most effective dose of the combination and will include women with or without a specific genetic mutation (PIK3CA) in their tumors.
What this could mean
Our plain-language read of the trial. This is informational only — not medical advice or a prediction.
- Active substance
- BYL719 (a PI3K inhibitor) combined with letrozole (hormone therapy)
- What this could lead to
- If successful, this combination could offer a new treatment option for hormone receptor-positive metastatic breast cancer, potentially slowing tumor growth.
- What could go wrong
- This is an early-phase trial focused on safety and dosing, so it's too soon to know if the combination will be effective. Side effects like high blood sugar, rash, and gastrointestinal issues are possible.
This is an AI summary of the original study and may miss details. Read our disclaimer.
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Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
Contacts and locations
Locations
-
Massachusetts General Hospital, Dana-Farber Cancer Institute
Boston, Massachusetts, 02114, United States
-
Vanderbilt-Ingram Cancer Center
Nashville, Tennessee, 37232-6838, United States
More trials for these conditions
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