Eos-001

**Eos-001** is a preclinical HER3-targeted Eosome developed by Eos Biosciences for **triple-negative breast cancer** and treatment-resistant or treatment-nonresponsive **HER2-positive breast cancer**. It is a self-assembling nanobiologic particle composed of a recombinant multifunctional polypeptide and a doxorubicin payload. The polypeptide is engineered for HER3-directed tumor-cell targeting, endosomal escape, and payload binding, with the goal of selectively delivering doxorubicin to HER3-overexpressing metastatic and drug-resistant tumors while reducing nonspecific exposure. The Eosome platform technology originated at Cedars-Sinai Medical Center and was exclusively licensed to Eos Biosciences.