The FDA has approved Intellia Therapeutics’ in vivo CRISPR therapy lonvoguran ziclumeran (lonvo-z) via a biologics license application, following successful Phase III results reported in the New England Journal of Medicine. The one-time, mRNA-lipid nanoparticle–based treatment targets hereditary angioedema, a rare genetic disease marked by recurrent, unpredictable swelling attacks. The approval follows the HAELO trial (NCT06634420), where the regimen demonstrated clinical benefit in preventing the debilitating episodes that can also become life-threatening when they involve the upper airway. Investigators framed the therapy as potentially shifting patients from recurrent drug dosing to a durable, single administration approach. Clinicians highlighted the burden of unpredictability—both physically and psychologically—underscoring how a one-dose modality could change day-to-day disease management. The BLA decision also positions the therapy as a near-term benchmark for future in vivo CRISPR programs targeting rare, high-need genetic disorders.