Intellia therapy gains first FDA approval for in vivo gene editing

Four years of effective treatment data

Data released by Intellia Therapeutics shows the therapy remains effective four years after administration. The drug, named lonvoguran ziclumeran, targets hereditary angioedema by disabling the gene for prekallikrein in the liver. This protein causes blood-vessel leakage leading to painful swelling in the throat and other body parts. John Leonard, Intellia's chief executive, told investors on 12 November that approval would make it the world's first in vivo CRISPR medicine.

Current approved therapy requires cell removal

The only currently approved CRISPR therapy is Casgevy, which treats sickle cell anemia and beta-thalassemia. Physicians must remove blood stem cells from the recipient before sending them off for gene editing outside the body. Edited cells are then infused back into the patient after harsh chemotherapy treatment to make room. Conversely, lonvo-z contains fatty particles wrapping mRNA for CRISPR-Cas9 components and is infused straight into the blood.

Safety concerns follow previous clinical hold

In the previous year, the FDA halted two additional in vivo trials funded by Intellia following the death of a participant due to liver injury. This year, the agency removed the restriction following a mandate for enhanced safety protocols in upcoming tests. Recipients of in vivo approaches face risks like harmful immune responses or unwanted edits at other genome locations. Jonathan Bernstein, a specialist at the University of Cincinnati, noted the four-year data is very reassuring for patients.