CRISPR Gene Therapy Slashes Cholesterol in Early Trial
A single infusion of an experimental CRISPR-Cas9 gene-editing therapy has safely reduced LDL cholesterol by nearly 50% and triglycerides by approximately 55% in a small early-stage trial, according to results presented at the American Heart Association’s Scientific Sessions 2025 and simultaneously published in The New England Journal of Medicine. The findings, though preliminary, raise the tantalizing possibility of a one-time “cure” for heart disease — the leading cause of death in the United States.
The Promise of a One-and-Done Approach
The experimental therapy, known as CTX310 and developed by CRISPR Therapeutics, uses lipid nanoparticles to deliver CRISPR-Cas9 components directly to the liver. Once there, the therapy permanently edits the ANGPTL3 gene, switching it off. People born with natural mutations that deactivate this gene enjoy lifelong low cholesterol and triglyceride levels with no apparent harmful effects, making it an ideal target for gene editing.
In the Phase 1 trial, 15 adults with elevated lipid levels despite maximum tolerated therapies received a single intravenous infusion of CTX310 at one of five dose levels. The results exceeded expectations: at the highest dose (0.8 mg/kg), LDL cholesterol and triglycerides dropped by up to 60%. Reductions appeared within the first two weeks and were sustained through at least 60 days of follow-up.
“This is really unprecedented. A single treatment that simultaneously lowered LDL cholesterol and triglycerides,” said Dr. Luke J. Laffin, lead study author and a preventive cardiologist at the Cleveland Clinic, as reported by the American Heart Association. “If confirmed in larger trials, this one-and-done approach could transform care for people with lifelong lipid disorders and dramatically reduce cardiovascular risk.”
The Adherence Crisis in Heart Disease Prevention
Heart disease kills nearly 700,000 Americans every year, and high LDL cholesterol is a major risk factor for heart attacks and strokes. An estimated 86.4 million U.S. adults — about 35% — have total cholesterol levels of 200 mg/dL or higher. Millions rely on daily statins and other medications to manage their cholesterol, but adherence remains a persistent challenge.
“Adherence to cholesterol-lowering therapy is one of the biggest challenges in preventing heart disease,” said Dr. Steven E. Nissen, a co-author of the study and chief academic officer at the Cleveland Clinic Heart, Vascular and Thoracic Institute. “Many patients stop taking their cholesterol medications within the first year. The possibility of a one-time treatment with lasting effects could be a major clinical advance.”
A one-time gene-editing treatment could eliminate the need for daily or monthly medications, potentially transforming how cardiovascular disease is prevented and managed.
Safety and Limitations
The trial was designed primarily to assess safety, and the results were encouraging. No dose-limiting toxic effects were observed. Three participants experienced minor infusion-related reactions — back pain and nausea — that resolved with medication. One participant with pre-existing elevated liver enzymes had a temporary further rise that resolved without treatment.
However, researchers and independent experts alike caution that these results are very preliminary. The study included only 15 participants, predominantly male (13 of 15), and was conducted at six sites in Australia, New Zealand, and the United Kingdom. The follow-up period was limited to 60 days, leaving questions about long-term durability and safety unanswered.
Dr. Eric Topol, a cardiologist at Scripps Research who was not involved in the study, offered a measured perspective in NPR’s coverage: “The idea of an inexpensive, one-and-done [treatment], so you don’t have to take any of those drugs, right now that’s an idea — a fantasy — because gene-editing is expensive, long-term safety is unclear.”
Dr. Kiran Musunuru, scientific director of the Center for Inherited Cardiovascular Medicine at the University of Pennsylvania, agreed: “It’s a step in the right direction. It could be a very important tool. But to actually prove it’s protective against cardiovascular disease you need to do more study.”
The Road Ahead
Phase 2 studies are planned to begin in late 2025 or early 2026, focusing on broader, more diverse patient populations and longer-term outcomes. The U.S. Food and Drug Administration recommends long-term safety monitoring for up to 15 years for all CRISPR-based therapies, so the path to regulatory approval will be lengthy.
Cost remains a significant unknown. Other gene-editing and gene therapies have carried price tags of up to millions of dollars per patient. Neither CRISPR Therapeutics nor Verve Therapeutics, which is developing a similar approach in Boston, has announced pricing. If the treatment proves expensive, it could exacerbate existing health disparities and limit access to those who need it most.
A Transformative Possibility
Despite the caveats, the scientific community is cautiously optimistic. Fyodor Urnov, a gene-editing researcher at UC Berkeley, captured the sentiment: “Having a CRISPR medicine for heart attack would be an extraordinary win.”
Samarth Kulkarni, CEO of CRISPR Therapeutics, noted that the approach “could potentially impact millions of people around the world.”
The trial represents a major milestone in the application of gene-editing technology to preventive cardiology. If subsequent studies confirm the durability and safety of CTX310, the era of one-and-done heart disease prevention may be closer than ever — transforming the lives of millions at risk for the world’s deadliest disease.
This article is based on research compiled from the American Heart Association, NPR, the American College of Cardiology, and The New England Journal of Medicine.