The purpose of this study is to better understand how the immune system plays a role in fighting breast cancer and specifically research if the immune system response against breast cancer can be improved with endocrine therapy and cyclin dependent kinase inhibitor therapy in patients with hormone receptor positive breast cancer. This will be studied by collecting tumor tissue and blood samples before and after 2 weeks of study treatment with commonly used endocrine therapy and cyclin dependent kinase inhibitor therapy.
Clinical stage operable stage I, II, or III invasive mammary carcinoma, which is estrogen receptor or progesterone receptor positive by immunohistochemistry and HER2 negative by Herceptest (0 or 1+) or not amplified by in situ hybridization as per routine clinical testing.
Have post-menopausal status, as defined by any of the following: Subjects at least 55 years of age OR Subjects under 55 years of age and amenorrheic for at least 12 months OR follicule stimulating hormone (FSH) values ≥ 40 IU/L and estradiol levels ≤ 40 pg/mL (140 pmol/L) or in postmenopausal ranges per local or institutional reference ranges.
Breast tumor ≥1cm in diameter by either physical exam or ultrasound and suitable for pre and post-treatment tissue sampling.
Meet either of 2 following criteria, for which neoadjuvant endocrine therapy for 2 weeks is deemed suitable: 1) disease that is planned for surgery as initial therapy, in which 2 weeks of neoadjuvant endocrine therapy is deemed suitable, 2) Disease for which neoadjuvant systemic therapy (either chemotherapy or endocrine therapy) may be planned, in which 2 weeks of neoadjuvant endocrine therapy prior to start of systemic therapy is deemed suitable.
Active metastatic breast cancer, inflammatory breast cancer, or locally recurrent breast cancer.
The patient has serious and/or uncontrolled preexisting medical condition(s) that, in the judgment of the investigator, would preclude participation in this study (for example, interstitial lung disease, severe dyspnea at rest or requiring oxygen therapy, severe renal impairment [e.g. estimated creatinine clearance <30ml/min], history of major surgical resection involving the stomach or small bowel, or a preexisting chronic condition resulting in baseline grade 2 or higher diarrhea).
Females who are pregnant, lactating, or premenopausal.
Severe uncontrolled malabsorption condition or disease (i.e. grade 2 or higher diarrhea, severe malnutrition, short gut syndrome).
Parallel
Letrozole
DrugOral. Tablets should be taken at the same times every day, with or without food.
Abemaciclib
DrugOral. Tablets should be taken at the same times every day, with or without food.
Change in T cell activation
Change in T cell activation between matched pre-treatment and on-treatment tissue samples of responder patients treated with abemaciclib and letrozole. T cell activation will be defined as the density of granzyme positive CD8 T cells detected on multiplex immunohistochemistry. Responders are defined as having complete cell cycle arrest by Ki-67.
Click on the lead sponsor to view all of their trials.
University of Texas Southwestern Medical Center
Lead sponsor
Eli Lilly and Company
Collaborator
Cancer Prevention Research Institute of Texas
Collaborator
