Trial testing gene-editing therapy PBGENE-DMD gets FDA green light
Developer will host virtual event in March with focus on FUNCTION-DMD study
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The U.S. Food and Drug Administration (FDA) has cleared Precision Biosciences to launch a clinical trial testing its gene-editing therapy candidate PBGENE-DMD in people with Duchenne muscular dystrophy (DMD) caused by certain mutations.
Precision announced it had received a “Study May Proceed notification” from the U.S. regulatory agency that will allow clinical testing of the therapy’s safety, tolerability, and effectiveness.
“We’re excited to bring this novel gene excision approach for DMD to the clinic with the goal of activating the first clinical site in the U.S. in the first half of 2026,” Michael Amoroso, CEO of Precision, said in a company press release.
The developer said it is already working with many DMD trial sites to get the trial, dubbed FUNCTION-DMD, up and running.
Further, Precision is planning a virtual event in March “with participation from key opinion leaders including patient advocacy” that will focus on both PBGENE-DMD and the FUNCTION-DMD trial, the company announced.
DMD is a genetic disorder that mainly affects boys. It’s caused by mutations in the gene that encodes dystrophin, a protein that’s vital for maintaining muscle health. People with DMD produce virtually no functional dystrophin protein, and as a result, muscles accumulate damage over time, leading to disease symptoms such as muscle weakness and wasting.
Like other protein-coding genes, the gene that encodes dystrophin is made up of sections called exons. When the gene is read to produce dystrophin protein, the exons are strung together to form the full protein-coding sequence — sort of like putting together multiple words to form a sentence.
Most DMD-causing mutations — about 60%, according to Precision — affect a specific region of the gene between exons 45 and 55. PBGENE-DMD essentially aims to permanently correct this section of the gene. According to Precision, this should facilitate production of a version of the dystrophin protein that’s about 80% the length of the naturally occurring protein. The company noted that DMD gene therapies generally deliver a gene encoding a version of dystrophin that’s only about a third the size of the natural version.
Trial will test gene-editing therapy in boys able to walk
Precision stated that PBGENE-DMD is intended to provide long-lasting functional benefits and that preclinical studies support such improvements in skeletal and cardiac muscles. The ability to edit satellite cells in muscles, a type of stem cell, has also been shown, according to the company.
Aravindhan Veerapandiyan, MD, director of the comprehensive neuromuscular program at Arkansas Children’s Hospital, University of Arkansas for Medical Sciences, noted that DMD “is a progressive disorder caused by mutations in the dystrophin gene that disrupt the production of the functional protein, resulting in continuous muscle degeneration.
Treatment with this gene-editing therapy may change that, Veerapandiyan said, noting that “PBGENE-DMD is designed to restore near full-length dystrophin, with the potential to provide significant functional benefits.”
PBGENE-DMD is … the first ever gene editing approach designed to treat the majority of DMD patients. Families are urgently waiting for newer therapies that can meaningfully and durably change the course of this disease.
The FUNCTION-DMD trial will test the therapy in boys who carry a DMD-causing mutation between exons 45 and 55, and who are able to walk. The study’s main goals will be to assess the safety and tolerability of the PBGENE-DMD, as well as its impact on dystrophin protein levels and functional outcomes.
The trial’s clearance was welcomed by Parent Project Muscular Dystrophy, a U.S.-based advocacy organization.
“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 CEO of the nonprofit. “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.”
FUNCTION-DMD expected to start before end of June
Precision said it expects to start the Phase 1/2 study by mid-year, with initial data expected before the end of the year. Once the company has data from 10 patients, it plans to meet with the FDA to discuss next steps for PBGENE-DMD’s development.
“We look forward to learning more as the FUNCTION-DMD study begins and to continued collaboration between patient advocates, physicians and developers of new treatments to accelerate progress for every person living with Duchenne,” Furlong said.
The developer also is planning a virtual investor event that will follow the Muscular Dystrophy Association annual meeting in March. More details will be released soon, Precision said, but noted that the event will include members of the medical and patient advocacy community.
The FDA has previously awarded PBGENE-DMD orphan drug and rare pediatric disease designations, both of which aim to incentivize the development of new treatments for rare disorders.
