Precision medicine for the treatment of triple negative breast cancer: opportunities and challenges

ABSTRACT Introduction: Triple negative breast cancer (TNBC) is a challenging disease generally following an aggressive clinical phenotype with poor survival outcomes. Scarcity of druggable targets coupled with molecular and genetic diversity has raised barriers in effective management of this disease; however, novel therapeutic strategies are on the horizon. Areas covered: We aim to present an overview of promising drugs that have emerged from preclinical studies undergoing investigation in early and late clinical trials alongside current challenges in the implementation of these in clinic. Expert opinion: The advent of immunotherapy and PARP inhibitors has finally started to diversify the cytotoxic chemotherapy-dependent treatment portfolio for TNBC. During this process, numerous challenges around novel biomarker discovery, optimum patient selection and combinatorial toxicity have been exposed. There is a clear need to further our understanding of the molecular pathways involved in the evolution of TNBC to optimize targets and explain inadequacies of current investigational treatments. We expect progressive expansion in diagnostic and prognostic biomarker panels allowing for further personalization of TNBC treatment.