Development of High-Loading Trastuzumab PLGA Nanoparticles: A Powerful Tool Against HER2 Positive Breast Cancer Cells.

TZPs exert more robust effects than free trastuzumab via a dual mode of action: TZPs are taken up by cells through an endocytosis mechanism and release the drug intracellularly for longer time. Additionally, the TZPs that remain in the extracellular space release trastuzumab which binds to the cognate receptor and impairs downstream signalling. This is the sole modality used by free trastuzumab. Remarkably, half dose of TZPs is as efficacious as the highest dose of free drug supporting their possible use for drug delivery in vivo.