ToolGen’s gene editor for hemophilia A and B; plus Praxis, TellBio and more

ToolGen Inc. (KOSDAQ:199800) and Seoul National University have developed a CRISPR-Cas9, lipid nanoparticle-based gene editor to target AT3 in the liver to treat hemophilia. By permanently editing the genome, the approach could offer greater durability than non-integrating gene therapies, and inhibiting AT3, a negative regulator of thrombin production, rather than delivering a clotting factor could avoid induction of anti-factor antibodies that limit efficacy of approved treatments.

In mouse models of hemophilia A and B, the therapy improved thrombin generation and reduced spontaneous bleeding, with no off-target edits, liver-induced toxicity or substantial anti-Cas9 immune responses. The results were published in Science Advances...