This study developed a multifunctional, trastuzumab-conjugated nanoparticle system for HER2-targeted co-delivery of neratinib and docetaxel, designed to achieve: (1) enhanced tumor-specific accumulation, (2) controlled dual-drug release kinetics, (3) mitigation of resistance mechanisms (e.g., P-glycoprotein efflux), and (4) synergistic anticancer activity. Here, ABCB1 is linked to neoplasm.