N093B: Phase I/II Study of Panobinostat (LBH589) and Letrozole in Patients with Triple Negative Metastatic Breast Cancer

Study Status

Open to Enrollment

Study Description

This is a clinical trial for people with metastatic breast cancer that is considered “triple negative,” meaning breast cancer that does not express genes for estrogen receptor (ER), progesterone receptor (PR) or HER2.

The purpose of this study is to determine how well people with metastatic breast cancer respond to treatment with the experimental drug panobinostat (also called LBH589) when it is given with letrozole. The study will also evaluate the safety of panobinostat when combined with letrozole.

Panobinostat may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Estrogen can cause the growth of breast cancer cells. Hormone therapy using letrozole may fight breast cancer by lowering the amount of estrogen the body makes. Giving panobinostat together with letrozole may be an effective treatment for breast cancer.

Treatment cycles in this study are 28 days. Study participants will take panobinostat (as a tablet by mouth) once daily on Days 1, 3 and 5 in weeks 1-4 and oral letrozole once daily on days 1-28. Treatment cycles repeat every 28 days as long as participants are responding to treatment and tolerating the medications. After completing study therapy, participants will be followed up every 3 to 6 months for up to 5 years.

Follow the Weill Cornell Breast Center Online:

Blog: CornellBreastCenter.com

Facebook: http://www.facebook.com/CornellBreastCenter

Twitter: https://twitter.com/cornellbreastcr

Disease Status and/or Stage

Triple Negative Metastatic Breast Cancer


Cancer Trials Support Unit (CTSU)

Key Eligibility

  • Men and women with metastatic breast cancer
  • Cancer must be unresected (has not been removed by surgery)
  • Women must be postmenopausal based on one of the following criteria:
    • Age 60 or older
    • Age 45 or older with last menstrual period ≥12 months before entering the study
    • Bilateral oophorectomy (surgical removal of both ovaries)
  • Men must be age 18 or older
  • Prior therapy:
    • Zero or 1 prior chemotherapy regimens for breast cancer (no more than 1 prior chemotherapy regimen)
    • ≤2 prior aromatase inhibitor regimens (including letrozole)
  • Detailed eligibility reviewed when you contact the study team

Principal Investigator

Tessa Cigler, MD


Protocol ID


Healthy Volunteers


As a healthy volunteer in a clinical trial you may make a significant contribution to the discovery of medical knowledge and new treatments that could impact people around the world.
Click here for studies seeking healthy volunteers.

Contact Us

For general inquiries, or if you need assistance finding a study, please contact:

Erica Bersin
Tel: (646) 962-8232
[email protected]

Top of page