A Phase 2 Pilot Feasibility Study of Palbociclib in Combination with Adjuvant Endocrine Therapy for Hormone Receptor Positive Invasive Breast Carcinoma.


Location(s): United States


This research study is evaluating a drug called Palbociclib in combination with endocrine therapy as a possible treatment for hormone receptor positive breast cancer.

  • Palbociclib is a drug that may stop cancer cells from growing. Palbociclib blocks activity of two closely related enzymes (proteins that help chemical reactions in the body occur), called Cyclin D Kinases 4 and 6 (CDK 4/6). These proteins are part of a pathway, or a sequence of steps which is known to regulate cell growth. Laboratory testing has suggested palbociclib may stop the growth of hormone receptor positive breast cancer.
  • Endocrine therapy prevents breast cancer cell growth by blocking estrogen stimulation. During this study endocrine therapy will either be tamoxifen or an aromatase inhibitor. It is standard of care for premenopausal women to take tamoxifen and for postmenopausal women to take either an aromatase inhibitor or tamoxifen after a diagnosis of hormone receptor positive breast cancer.