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A Phase I Study of LJM716, BYL719, and Trastuzumab in Women with Metastatic HER2-Positive Breast Cancer

Full Title

A Phase I, Open-Label Study Evaluating the Safety and Tolerability of LJM716, BYL719 and Trastuzumab in Patients with Metastatic HER2+ Breast Cancer


Trastuzumab is an anticancer drug used to treat breast cancers that produce the HER2 protein. However, in some women, the cancer becomes resistant to trastuzumab and continues to grow. This resistance may develop because two proteins become activated: PI3 kinase (PI3K) and HER3. Combining trastuzumab with drugs that block these two proteins may be an effective way to treat HER2-positive breast cancer.

LJM716 is a drug that blocks some functions of HER3. It is given intravenously (by vein). BYL719 works by blocking some functions of PI3K. It is taken orally (by mouth). Both LJM716 and BYL719 are investigational drugs. In this study, researchers want to find the highest dose of BYL719 that can be given safely with LJM716 and trastuzumab (which is also given intravenously) in women with advanced HER2-positive breast cancer.


  • Patients must have metastatic HER2-positive breast cancer that contains a PI3K mutation.
  • Patients may have had any number of prior therapies.
  • At least 3 weeks must pass since completion of previous therapy and entry into the study, except for trastuzumab. Patients who are already on trastuzumab may continue to receive this treatment.
  • Patients must be physically well enough that they are fully ambulatory, capable of all self care, and are capable of all but physically strenuous activities. As an example, patients must be well enough that they would be able to carry out office work or light housework.
  • This study is open to patients age 18 and older.

For more information about this study and to inquire about eligibility, please contact Dr. Shanu Modi at 646-888-5243.