According to the results of the MONARCH-2 trial, the FDA approved abemaciclin in association with fulvestrant for the treatment of HR-positive, HER2-negative breast cancer patients with advanced/metastatic disease; furthermore, according to the results of the MONARCH-1 study, FDA approved abemaciclib as monotherapy in breast cancer patients HR-positive, HER2-negative with advanced/metastatic disease. Here, ERBB2 is linked to breast cancer.