Circio Holding and Avenue Biosciences agreed to a research collaboration designed to combine their synergistic technologies to improve long-term expression of secreted proteins, relevant for treatment of a broad range of diseases.
Secreting proteins from cells into surrounding tissue, or into circulation, opens new treatment opportunities beyond classical gene therapy for monogenic disease, say scientists from both companies. Circio maintains that its circVec platform drives higher and more durable protein expression, and a spokesperson from Avenue Biosciences explains that its protein engineering technology improves protein secretion from cells by screening thousands of signal peptide-protein combinations.
Circio and Avenue will jointly explore whether the two technologies in combination can act synergistically to improve the production and secretion of proteins, including antibodies, for the treatment of genetic and chronic diseases.
“Many gene therapies are limited by insufficient protein expression, driving high doses, manufacturing complexity, and cost. The secretory pathway—the cellular machinery that produces and exports proteins—is a largely underutilized engineering opportunity. By combining Circio’s durable circular RNA expression with our technology, we aim to increase protein output per dose and ultimately help more patients benefit from life-changing genetic medicines,” says Avenue Biosciences CEO Tero-Pekka Alastalo, MD, PhD.
In the collaboration, Avenue Biosciences will deploy its protein engineering platform to identify signal peptides that enable improved secretion of therapeutic proteins expressed by circVec. The initial screening will be performed by Avenue Biosciences, followed by further in vitro and in vivo testing by Circio.
“A significant proportion of therapeutically relevant payloads for circVec are secreted proteins,” adds Victor Levitsky, PhD, CSO of Circio. “With the Avenue platform, we will test how signal peptide optimization can enhance secretion of proteins and thereby open novel opportunities for the circVec platform in genetic and chronic disease. This collaboration is an important addition to our pre-clinical development strategy of testing circVec in multiple settings through R&D partnerships to broadly explore the range of therapeutic options available for our unique circular RNA expression technology.”

