LXG6403 is a potent, irreversible lysyl oxidase (LOX) inhibitor with an IC₅₀ of 1.3 μM in MDA-MB-231 cells, demonstrating approximately 3.5-fold selectivity over LOXL2 and no activity against LOXL1. It effectively inhibits LOX activity across multiple triple-negative breast cancer (TNBC) cell lines, including HCC143, Hs-578-T, and HCC1937, with IC₅₀ values below 5 μM. In preclinical models, LXG6403 enhances chemosensitivity to agents such as doxorubicin, cisplatin, and paclitaxel by disrupting collagen crosslinking, thereby reducing tumor stiffness, improving drug penetration, inhibiting FAK signaling, and inducing ROS-mediated DNA damage leading to G1 arrest and apoptosis. Notably, in the TM01278 TNBC patient-derived xenograft model, LXG6403 overcame doxorubicin resistance without significant toxicity, underscoring its potential as a therapeutic agent in LOX-driven, chemoresistant cancers
