in one step Towards the widespread use of gene editing, a treatment that uses Crispr has successfully reduced high cholesterol levels in a small number of people.
In a trial run by Swiss biotech company Crispr Therapeutics, 15 participants received a one-time infusion to turn off a gene in the liver. ANGPTL3. Although rare, some people are born with a mutation in this gene that protects against heart disease with no apparent adverse consequences.
The highest dose tested in the trial reduced both “bad” LDL cholesterol and triglycerides by an average of 50 percent within two weeks of treatment. The effect lasted at least 60 days, the length of the trial. The findings were presented and published today at the American Heart Association’s annual meeting New England Journal of Medicine.
A Gene Editing Therapy Cut
The Nobel Prize-winning Crispr technology has mostly been used to address rare diseases, but these latest findings, while preliminary, add to evidence that the DNA-editing tool could also be used to treat common conditions.
“This will probably be one of the biggest moments in the development of Crispr in medicine,” Samarth Kulkarni, CEO of Crispr Therapeutics, told Wired. The company is behind the only approved gene-editing treatment on the market, Casgevy, which treats sickle cell disease and beta thalassemia.
American Heart Association guess About a quarter of adults in the United States have elevated LDL levels. A similar number has high triglycerides. LDL cholesterol is the waxy substance in the blood that can clog and harden arteries over time. Triglycerides, meanwhile, are the most common type of fat found in the body. High levels of both increase the risk of heart attack and stroke.
The phase I trial was conducted between June 2024 and August 2025 in the UK, Australia and New Zealand. Participants ranged in age from 31 to 68 years and had uncontrolled levels of LDL cholesterol and triglycerides. The trial tested five different doses of the Crispr infusion, which took an average of about two and a half hours to administer.
“These are very sick people,” said Steven Nissen, senior author and chief academic officer of the Cleveland Clinic’s Heart, Vascular and Thoracic Institute, which independently confirmed the test results. “The tragedy of this disease is not only that people die young, but some of them will have heart attacks and their lives will never be the same again. They don’t go back to work, they have heart failure.”
One trial participant, a 51-year-old man, died six months after receiving the lowest dose of treatment, which was not associated with reductions in cholesterol and triglycerides. The death was related to his existing heart condition, not the experimental CRISPR treatment. The man had a rare, inherited genetic form of high cholesterol and had previously had several procedures to improve blood flow to his heart.