Precision BioSciences cleared to begin gene therapy trial for muscular dystrophy
Durham-based Precision BioSciences, a gene-editing company, has received regulatory clearance to begin a clinical study of its potential treatment for Duchenne muscular dystrophy (DMD), a rare muscle-degeneration disease that mostly affects boys.
The company received a Study May Proceed notification from the U.S. Food and Drug Administration (FDA), allowing it to begin preparing for a Phase 1/2 clinical trial of the therapy at highly specialized clinical trial sites.
The study will evaluate the safety, tolerability and efficacy of the treatment, a one-time gene therapy intended to permanently correct a faulty gene that causes DMD.
The FDA notification “represents yet another regulatory achievement for Precision BioSciences as we advance our second wholly owned program toward the clinic,” said Michael Amoroso, chief executive officer of Precision.
The company’s other treatment, already in a Phase 1/2 trial, is a gene therapy intended to cure hepatitis B, a serious viral infection of the liver (see link at the bottom).
The goal for the DMD therapy is to activate the first clinical trial site in the first half of this year, with others to follow, Amoroso said. Initial data from five to eight ambulatory patients is expected by the end of the year.
If successful in the clinic, Precision plans to treat 35 to 40 patients in Phase 1, 2 and 3 trials and file a biologics license application with the FDA in 2028.
A permanent genetic fix
The therapy, called PBGENE-DMD, is a first-in-class in vivo gene-editing treatment intended to permanently correct certain mutations in the gene for dystrophin, a protein vital to normal muscle function. The absence or dysfunction of dystrophin causes severe muscle-wasting diseases such as DMD.
The therapy would correct mutations in the dystrophin gene that are responsible for about 60% of patients with DMD.
“PBGENE-DMD is designed to restore near full-length dystrophin, with the potential to provide significant functional benefits,” said Aravindhan Veerapandiyan, M.D., director of the Comprehensive Neuromuscular Program for Arkansas Children’s Hospital at the University of Arkansas for Medical Sciences. Veerapandiyan is one of the researchers who will participate in the Phase 1/2 clinical study.
“PBGENE-DMD is an important step forward for the Duchenne community as it’s the first ever gene-editing approach designed to treat the majority of DMD patients,” said Pat Furlong, founding president and chief executive officer of Parent Project Muscular Dystrophy. “Families are urgently waiting for newer therapies that can meaningfully and durably change the course of this disease, and we are encouraged to see programs advancing that are designed to address the underlying genetic cause.”
Eight therapies have been approved by the FDA for treating various types of DMD. They work in different ways to slow disease progression or improve muscle function but have limitations.
“Despite approved therapies today, boys with DMD are lacking treatments that lead to functional improvements over time,” Amoroso said.
PBGENE-DMD offers several potential advantages over other therapies, according to Precision. It promises improved muscle function over time, a long-term durable benefit and broad applicability to patients. It is also given in a single administration and corrects the dystrophin gene, resulting in a functional dystrophin protein.
Precise gene-cutting platform
PBGENE-DMD is based on Precision’s proprietary genome-editing technology called ARCUS, which uses an enzyme to cut or insert specific DNA segments within a cell. In DMD patients, edits to the faulty dystrophin gene are intended to result in a naturally expressed, near full-length, functional dystrophin protein.
In preclinical studies, PBGENE-DMD demonstrated the ability to target key muscle types involved in the progression of DMD and produced significant durable, functional improvements in a humanized DMD mouse model. PBGENE-DMD restored production of a near full-length functional dystrophin protein across multiple muscles, including cardiac tissue and various key skeletal muscle groups. In addition, PBGENE-DMD edited satellite muscle stem cells, believed to be critical for long-term durability and sustained functional improvement.
PBGENE-DMD was recently granted FDA Rare Pediatric Disease and Orphan Drug designations for the treatment of DMD. The designations help accelerate the review and approval of treatments for diseases that affect relatively few patients.
About 15,000 patients in the U.S. and 300,000 globally live with DMD. The disorder affects about one in every 5,000 male births worldwide.
With newer treatments, more DMD patients are living into their 30s and 40s.
Precision BioSciences was founded in 2006 and became a publicly traded company in 2019.
In November 2025, it raised about $75 million in a stock offering. At the end of that year, the company reported having about $137 million in cash and other revenue, enough runway to last until 2028.
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