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Searching for Better Outcomes Among Patients with Metastatic Triple-negative Breast Cancer – Do We Have Novel Options on the Treatment Landscape?

Katarzyna Anna Rygiel (Department of Family Practice, Medical University of Silesia (SUM), Zabrze, Poland; 3 Maja St.; 41-800 Zabrze, Poland)


Triple-negative breast cancer (TNBC), which accounts for approximately 15% of breast cancers (BCs) is characterized by a lack of expression of the hormone receptors (HRs) (estrogen receptor (ER) and progesterone receptor (PR)), and human epidermal growth factor receptor 2 (HER2). TNBC reveals very aggressive behavior and often leads to poor prognosis. Unfortunately, standard chemotherapy (CHT) is related to low response rates and short progression-free survival (PFS) in patients with metastatic TNBC, creating an unmet need.

However, recent recognition of different molecular subtypes and mutations within TNBC has allowed exploring some innovative targeted therapies, bringing new hope for women suffering from TNBC. Currently, some promising systemic treatment options in this area have been developed, including targeted therapies, such as poly(ADP-ribose) polymerase (PARP) inhibitors, immune checkpoint inhibitors, antibody-drug conjugates, and AKT inhibitors.

The aim of this mini-review is to address these novel treatment modalities and highlight the main directions for further research and clinical practice in the advanced or metastatic forms of TNBC. This article presents poly(ADP-ribose) polymerase (PARP) inhibitors (e.g., olaparib, talazoparib, and valaparib for treatment of BRCA-mutated, HER2-negative metastatic BC), immune checkpoint inhibitors (atezolizumab and pembrolizumab), an antibody-drug conjugate (ADC) (sacituzumab govitecan), and AKT inhibitors (ipatasertib and capivasertib). A brief outline of the main clinical trials leading to the approval of these new medications has been provided. Moreover, this overview discusses the efficacy and safety of these innovative treatment options, focusing on women with metastatic TNBC. In addition, this paper comments on some  recent considerations, regarding avenues of delivering care and conduct clinical trials in patients with BC, during the COVID-19 pandemic.


Triple-Negative Breast Cancer (TNBC); Targeted therapies; Poly(ADP-ribose) polymerase (PARP) inhibitors; Immune checkpoint inhibitors; Antibody-drug conjugates (ADCs); AKT Inhibitors

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