Circio Holding and Avenue Biosciences agreed to combine Circio’s circVec platform with Avenue’s protein engineering capabilities to improve long-term expression and secretion of therapeutic proteins. The collaboration is positioned around optimizing signal peptides so circVec-expressed payloads can be exported more efficiently. Both companies framed the work as a response to a recurring gene-therapy limitation: insufficient protein expression can increase dose, complicate manufacturing, and constrain patient access. The partnership will begin with in vitro signal peptide screening before moving into further preclinical testing.