Current frontline endocrine treatment options for women with hormone receptor-positive, Human Epidermal Growth Factor Receptor 2 (HER2)-negative advanced-stage breast cancer.

Despite the recent advances in breast cancer early detection and awareness, a significant portion of patients present with an advanced-stage disease and more patients will progress to stage IV despite adequate treatment of their initial early-stage disease. Hormone receptor (HR)-positive, Human Epidermal Growth Factor Receptor-2 (HER2)-negative subtype is the commonest among all breast cancer subtypes. The management of the advanced-stage disease of this subtype has evolved significantly over the past few years. The emergence of estrogen receptor down regulators (fulvestrant), mTOR-inhibitors and the recent introduction of CDK4/6 inhibitors, like palbociclib, abemaciclib and ribociclib, has resulted in a significant and a historical improvement in treatment outcomes. In this paper, we review many of the recently reported clinical trials that led to the approval of these new drugs in the first-line settings, along with the current international guidelines.