Archive · 27 Oct 2025
Intellia Pauses CRISPR Trial Due to Liver Reaction
Intellia, a company working on new medicines, had to pause a study for a gene editing treatment called nex-z.
This treatment uses CRISPR technology, like a biological editor, to fix a gene that causes a disease called ATTR.
During a trial, one person got a serious liver problem, which caused the company to stop the study temporarily.
Doctors are taking care of the patient while the company figures out what happened.
The study involves people with heart and nerve problems.
The company is working with other experts and regulators to see how to continue the study safely.
More than 450 patients have already received the treatment in the trials.
Intellia paused Phase 3 trials (MAGNITUDE and MAGNITUDE-2) for its CRISPR therapy nex-z.
The pause followed a Grade 4 liver toxicity event in a patient dosed on September 30.
The patient is hospitalized and receiving treatment while being closely monitored.
Over 650 ATTR-CM patients and 47 ATTR-PN patients have been enrolled in the affected trials.
nex-z is designed as a potential one-time treatment for ATTR-CM and ATTR-PN.
- Who
- Intellia Therapeutics
- What
- Paused Phase 3 trials for nex-z after a patient developed severe liver toxicity.
- When
- The trial was paused after an incident reported on October 24th.
- Where
- The trials are global.
- Why
- Due to a severe adverse reaction (Grade 4 liver toxicity) in a patient, prompting safety concerns.
- Company
- Intellia Therapeutics
- Therapy
- nex-z (CRISPR-based)
- Trial Phases Paused
- MAGNITUDE and MAGNITUDE-2 (Phase 3)
- Patient Reaction
- Grade 4 liver toxicity
- Affected Diseases
- ATTR-CM, ATTR-PN
- Total Patients Dosed
- Over 450
- Collaborator
- Regeneron