Current gene therapies for genetic heart disease often require high doses of AAV vectors, with significant safety risks. According to Circio, its latest generation of circVec has increased gene expression from AAV vectors in the heart about 200-fold in vivo. POLARIS-101 is engineered to target heart muscle with reduced uptake in the liver and has shown encouraging early clinical safety data. The aim is to lower therapeutic doses and improve safety.

Circio will design the circVec constructs, which Solid will package in its capsid. The companies will jointly test the combined vectors in the lab and in animal models, and successful candidates will move into preclinical development. Circio’s circVec research is carried out by its subsidiary in Stockholm.

“We believe that circVec can build on POLARIS-101’s strong tropism to further amplify cardiac gene expression, potentially enabling next generation heart gene therapies with enhanced potency and specificity,” says Victor Levitsky, CSO of Circio.