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BYLieve (CBYL719X2402)


A Phase II Clinical Study for People With Advanced Breast Cancer and a PIK3CA Mutation Whose Disease Has Progressed on or After Treatment With a CDK4/6 Inhibitor

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The main goal of the study is to assess the amount of time that patients continue to live without their cancer progressing while being treated with alpelisib in combination with either fulvestrant or letrozole.

Participants in the study must be men and postmenopausal women with hormone receptor positive (HR+), human epidermal growth factor receptor-2 negative (HER2-) advanced breast cancer who have a phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) mutation and have progressed on or after treatment with a cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor.

You may be eligible to participate if you

  • Are a postmenopausal woman or a man aged 18 years or older
  • Have been diagnosed with HR+, HER2- advanced breast cancer
  • Have a confirmed PIK3CA mutation
  • Have cancer that has recurred or progressed during or after CDK4/6 inhibitor therapy
    • CDK4/6 inhibitor has to be last treatment regimen prior to study entry
  • Meet other eligibility criteria




Clinical Study Overview

Here is some information that may help you gain a better understanding of this study and its goals. By learning more about this study, you'll be able to make an informed decision with your doctor.

What are the possible drugs that I would receive in this study?

You will receive the investigational study drug alpelisib in combination with 1 of 2 endocrine agents (fulvestrant or letrozole) based on your prior treatment history.

In which disease is the investigational drug being studied?

The combination of alpelisib with either fulvestrant or letrozole is being studied for the treatment of PIK3CA mutant, HR+, HER2- advanced breast cancer that has progressed on or after treatment with a CDK4/6 inhibitor. The CDK4/6 inhibitor must be the last treatment regimen prior to study entry.

What should I know about the investigational drug in this study?

Alpelisib is given daily as a tablet. It is a type of drug called a phosphatidylinositol-3-kinase (PI3K) inhibitor. PI3K is a protein that plays an important role in the growth and survival of cancer cells.

PI3K may be overactive in many types of cancers, including HR+ breast cancer. Alpelisib is an investigational drug that may block, or may inhibit, PI3K and may be able to slow down or stop cancer growth. It has not been approved by the U.S. Food and Drug Administration (FDA) for this condition.

Fulvestrant is a drug given as an intramuscular injection. It prevents estrogen from acting on breast cancer cells, which can help the cells survive and grow. Fulvestrant is approved for the treatment of HR+ metastatic breast cancer in women whose cancer has progressed following other antiestrogen therapy.

Letrozole is given as a daily tablet. It is a type of drug called an aromatase inhibitor. This drug inhibits the conversion of adrenal androgens to estrogens, reducing overall estrogen levels. Letrozole is indicated for the treatment of advanced HR+ breast cancer both in the first-line setting as well as in women whose cancer has progressed following other antiestrogen therapy.

How many patients will participate in this study?

About 160 people in several countries around the world will participate in this study.

How long will I participate in this study?

The study may last up to 5 years. Your treatment with the study drugs, however, will continue as long as you benefit from treatment, until you experience unacceptable side effects, until you decide not to participate in the study anymore, until the study reaches its end points, or until Novartis terminates the study. Your study doctor can also decide to withdraw you from the study if he/she feels that this is best for you.

To learn more about this study, visit