Analysts Downplay Intellia Adverse Event, but Gene Therapy Safety Remains Under Scrutiny
Intellia Therapeutics reported a serious adverse event in its Phase III MAGNITUDE trial, where a patient experienced grade 4 liver transaminase elevations after treatment with gene-editing therapy nexiguran ziclumeran (nex-z) for ATTR cardiomyopathy (ATTR-CM)123.
The affected patient was asymptomatic; the elevated liver enzymes were detected via lab tests and resolved without hospitalization or medical intervention23.
Following the news, Intellia’s stock dropped nearly 23% in a single day, reflecting investor concern about the long-term safety of gene therapy treatments23.
Analysts and Intellia have downplayed the incident, emphasizing that this is a single event among over 200 dosed patients and noting that other adverse events observed were similar to those in earlier trials, such as infusion reactions and asymptomatic lab findings23.
Despite reassurances, the event underscores continuing investor and industry concern about gene therapy safety, particularly after recent high-profile adverse events in the broader sector, such as the March 2025 death of a patient in a separate Duchenne muscular dystrophy gene therapy trial3.
Enrollment for the MAGNITUDE Phase III trial is ongoing and projected to be completed by early 2027, with monitoring for additional safety events continuing23.
Sources:
1. https://www.precisionmedicineonline.com/business-news/intellia-reports-safety-event-phase-iii-trial-gene-editing-drug-attr-cm
2. https://www.nasdaq.com/articles/ntla-stock-down-patient-faces-adverse-event-gene-therapy-study
3. https://www.clinicaltrialsarena.com/news/intellia-stock-dips-following-safety-event-in-phase-iii-gene-therapy-trial/