Old Drugs, New Battles: Unleashing Repurposed Drug Classes in Triple-Negative Breast Cancer Treatment

Cancer remains a major global health challenge, with triple-negative breast cancer (TNBC) representing one of the most aggressive and difficult-to-treat subtypes, characterized by poor prognosis and limited therapeutic options. Current treatments, including chemotherapy, are hindered by high recurrence rates, drug resistance, and severe side effects, highlighting the urgent need for novel therapeutic strategies to address these challenges. Drug repurposing, which involves the application of existing FDA-approved (Food and administration) drugs for new oncological uses, offers a cost-effective and time-efficient alternative to traditional drug development. This review synthesizes recent findings on repurposed drugs, including antidiabetic, antiparasitic, antidepressant, antipsychotic, cardiovascular disease, and non-steroidal anti-inflammatory drugs (NSAIDs), and their potential to target TNBC through mechanisms such as immune modulation, interference with signaling pathways, and inhibition of cancer cell proliferation. Evidence suggests that these agents hold therapeutic promise across heterogeneous TNBC subtypes, although outcomes vary depending on the molecular context. Overall, drug repurposing has emerged as a promising avenue for expanding the treatment options for TNBC; however, further research and personalized approaches are essential to translate these findings into effective clinical applications.