What is gene insertion therapy and CRISPR technology?

CRISPR stands for “clustered regularly interspaced short palindromic repeats.” Cas9 is a CRISPR-associated protein 9. CRISPR technology has two parts which work together for gene insertion: a guide RNA strand and a Cas9 enzyme. The guide RNA strand guides the Cas9 enzyme precisely to a matching location within the DNA sequence. Only then will the Cas9 enzyme create a small opening for the new gene to be inserted.

The investigational treatment is a CRISPR-based targeted gene insertion therapy which works in two steps, which are both required for the therapy to work. The first step involves delivery where a viral vector delivers a therapeutic gene into a target liver cell, while a lipid-based carrier delivers the CRISPR technology to the target gene. The second step involves targeted insertion, where once inside the liver cell, CRISPR technology targets a precise location within the DNA, where the new, therapeutic gene is inserted. Together, the two steps are called CRISPR gene insertion. CRISPR gene insertion adds the new gene directly into the DNA at a precise location so that it becomes a permanent part of your DNA. This is different from some other gene therapies that involve a virus bringing a new gene into a cell that is not intended to become part of the DNA of the cell.

At this time, there are no approved therapies that are based on using CRISPR gene insertion. However, CRISPR technology is being studied in other clinical trials to treat other genetic diseases.