A phase III multicenter randomized open-label trial to evaluate efficacy and safety of ribociclib with endocrine therapy as an adjuvant treatment in patients with hormone receptor-positive HER2-negative early breast cancer (New Adjuvant TriAl with Ribociclib [LEE011]: NATALEE).

Are you eligible to participate in this study?

You may be eligible for this study if you meet the following criteria:

  • Conditions:
    Hormone Receptor-positive, Her2-negative, Early Breast Cancer
  • Age: Between 18 years - 100 years
  • Gender: Male or Female
  • Other Inclusion Criteria:
    1) Patient with histologically confirmed unilateral primary invasive adenocarcinoma of the breast with a date of initial cytologic or histologic diagnosis within 18 months prior to randomization. 2) Patient has breast cancer that is positive for ER and/or PgR according to the local laboratory as determined on the most recently analyzed tissue sample 3) Patient has HER2-negative breast cancer defined as a negative in situ hybridization test or an immunohistochemistry (IHC) status of 0 or 1+. If IHC is 2+, a negative in situ hybridization (FISH, CISH, or SISH) test is required to confirm the HER2-negative status (based on the most recently analyzed tissue sample tested by a local laboratory). 4) Patient has available archival tumor tissue from the surgical specimen, for submission to a central laboratory. 5) Patient after surgical resection where tumor was removed completely, with the final surgical specimen microscopic margins free from tumor, and who belongs to categories per protocol.

You may not be eligible for this study if the following are true:

  • 1) Patient has received any CDK4/6 inhibitor. 2) Patient has received prior treatment with tamoxifen, raloxifene or AIs for reduction in risk (“chemoprevention”) of breast cancer and/or treatment for osteoporosis within the last 2 years prior to PICF signature. 3) Patient has received prior treatment with anthracyclines at cumulative doses of 450 mg/m² or more for doxorubicin, or 900 mg/m² or more for epirubicin. 4) Patient with a known hypersensitivity to any of the excipients of ribociclib and/or ET (e.g. rare hereditary problems of galactose intolerance, the Lapp lactase deficiency, glucose-galactose malabsorption, and soy allergy). 5) Patient with distant metastases of breast cancer beyond regional lymph nodes (stage IV according to AJCC 8th edition) and/or evidence of recurrence after curative surgery.


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