Intellia Therapeutics reported the death of a patient who had been hospitalized with liver injury after receiving nex‑z, its LNP‑delivered in vivo CRISPR base‑editing therapy for transthyretin (ATTR) amyloidosis. The company paused dosing and both Phase 3 studies remain on hold while Intellia and regulators investigate grade 4 liver enzyme elevations and elevated bilirubin observed in a small number of patients. Intellia said the patient was in his early 80s and had comorbidities; the company has directed sites to add intensified early post‑dosing lab monitoring and is developing risk‑mitigation measures with external experts and the FDA.