May 27, 2026 —
Circio Holding and AaviGen announced a research collaboration to develop next-generation AAV vectors for heart-directed gene therapy, combining Circio’s circVec circular RNA expression platform with AaviGen’s proprietary cardiac-targeted AAV capsids.
The collaboration aims to address two major challenges in AAV-based cardiac gene therapy: achieving strong therapeutic gene expression in heart tissue while reducing the vector dose needed for clinical efficacy. High systemic AAV doses can increase safety concerns, particularly through off-target biodistribution and toxicity. By combining enhanced expression with more precise cardiac delivery, the companies hope to improve both potency and safety.
Circio’s circVec platform has demonstrated up to 40-fold enhanced gene expression from AAV vectors in heart tissue, while AaviGen’s capsids are designed to target cardiomyocytes with improved specificity. The companies believe these technologies may work synergistically: AaviGen’s capsids could improve delivery to the heart, while Circio’s circVec cassette could increase expression once the payload reaches target cells.
The research collaboration will proceed in three stages. First, the companies will produce novel AAV vectors combining AaviGen’s heart-targeted capsids with Circio’s circVec expression cassette. Second, the vectors will be tested and characterized in vitro. Third, the most promising designs will be evaluated in vivo, with a focus on biodistribution and gene expression profiles across different vector configurations.
If successful, the combined platform could support lower-dose, heart-targeted AAV gene therapies for inherited cardiac diseases and chronic heart failure. For cardiac indications, where broad delivery to cardiomyocytes and long-term safety are both critical, the ability to maximize on-target expression while minimizing off-target exposure may be especially important.
The collaboration reflects a broader trend in gene therapy development: next-generation AAV programs are increasingly being designed through integrated vector engineering, where capsid targeting, expression cassette design, tissue specificity, dose reduction, and safety are optimized together from the start.
