Circio Holding ASA (OSE: CRNA; reference: 0RIS), an Oslo-based biotechnology company developing circular RNA expression technology for gene and cell therapy, has announced a research collaboration with Nasdaq-listed Solid Biosciences Inc. (Nasdaq: SLDB) to evaluate combining Circio's circVec platform with Solid's proprietary next-generation AAV capsid, POLARIS-101, targeting genetic heart disease. The collaboration aims to address significant unmet medical needs in cardiac gene therapy, where current approaches often require high systemic AAV doses carrying notable safety risks. Investors will be watching for early pre-clinical results that could validate the combined technology platform and broaden Circio's pipeline.

Key Points

  • Circio Holding ASA (0RIS), listed on the Oslo Stock Exchange as CRNA, is a biotechnology company developing circular RNA expression technology for gene and cell therapy
  • Circio and Solid Biosciences have entered a research collaboration to integrate circVec generation 5 with the POLARIS-101 AAV capsid for genetic heart disease
  • Circio's circVec generation 5 has demonstrated up to 200-fold enhanced gene expression from AAV vectors in the heart in vivo
  • Investors should watch for in vitro and in vivo characterisation results and any progression of combined vectors into pre-clinical development

Circio's circVec Generation 5 Demonstrates Up to 200-Fold Enhanced Cardiac Gene Expression in AAV Vectors

Circio, whose circVec R&D activities are conducted through its wholly owned subsidiary Circio AB in Stockholm, Sweden, has developed a modular circular RNA vector platform with demonstrated capabilities in multiple therapeutic settings. The latest circVec generation 5 construct has shown up to 200-fold enhanced gene expression from AAV vectors in the heart in vivo, a significant performance improvement over conventional approaches. The circVec platform has also demonstrated 75-fold increased RNA half-life and up to 60-fold enhanced protein expression versus conventional mRNA-based vector systems, positioning it as a potentially transformative gene expression technology across cardiac, ocular, and CNS indications.

Solid Biosciences' POLARIS-101 Capsid Engineered for Cardiac Muscle Targeting with Reduced Liver Biodistribution

Solid Biosciences' proprietary POLARIS-101 is a next-generation AAV capsid specifically engineered for enhanced cardiac and skeletal muscle tropism, with reduced liver biodistribution compared with conventional AAV delivery vectors. The announcement states that POLARIS-101 has generated encouraging early clinical safety data, an important milestone given that high systemic AAV doses in current gene therapy approaches carry significant safety concerns. By pairing POLARIS-101's precise tissue targeting with circVec's amplified gene expression, the collaboration intends to design vectors that could reduce therapeutic dose levels while maintaining or improving potency.

Collaboration Structure: Circio Supplies Constructs, Solid Packages Using POLARIS-101 and Dual Plasmid Platform

Under the agreed collaboration structure, Circio will generate circVec generation 5 constructs, which Solid Biosciences will then package using its proprietary POLARIS-101 capsid and dual plasmid manufacturing platform. Both parties will jointly characterise and test the resulting combined AAV vectors in vitro and in vivo. The announcement states that successful outcomes could lead to potential therapeutic candidates being progressed into pre-clinical development. Financial terms of the collaboration were not disclosed in the announcement. The company did not disclose this figure in the announcement.

Circio's Broader R&D Strategy Targets circVec Deployment Across Heart, Eye, and CNS Tissue Applications

The collaboration with Solid Biosciences forms part of Circio's wider R&D strategy to test its circVec platform alongside complementary, state-of-the-art delivery solutions for heart, eye, and CNS tissues. The company's platform addresses genetic medicine, cell therapy, and chronic disease applications, with the circVec construct designed for efficient biogenesis of multifunctional circular RNA inside target cells. A key risk specific to Circio is that pre-clinical and in vivo studies may not replicate anticipated performance levels, and progression into therapeutic development is contingent on successful joint characterisation results from this early-stage research collaboration.