China's Original RNA Editing Technology First Applied to Rare Disease Treatment in the World

Background

Duchenne muscular dystrophy (DMD) is a severe hereditary rare disease caused by mutations in the DMD gene that encodes dystrophin, a protein critical for muscle function. The condition leads to progressive muscle atrophy, loss of motor abilities usually in childhood, and ultimately respiratory or cardiac failure, with most patients not surviving into middle age. China has one of the largest numbers of DMD patients globally. Conventional treatments have been limited to slowing disease progression without addressing the root genetic cause.

The LEAPER RNA editing technology was originally developed by the team of Professor Wei Wensheng at Peking University and Changping Laboratory. Unlike approaches that introduce foreign editing enzymes, LEAPER recruits the body's own ADAR (adenosine deaminase acting on RNA) enzymes using engineered RNA molecules. The platform has been upgraded to versions such as LEAPER 2.0, employing circular ADAR-recruiting RNA (circ-arRNA). This technology was advanced through collaboration with Shanghai Children's Medical Center, Kunming University of Science and Technology and other partners for application to DMD.

What was achieved

Researchers achieved the world's first application of an original Chinese RNA editing technology to treat a rare disease, specifically using it for DMD. The candidate therapeutic LE051, based on AAV-delivered circ-arRNA designed to induce exon 51 skipping, was administered in a first-in-human clinical study at Shanghai Children's Medical Center. Three children with DMD received the treatment.

One-year follow-up showed dose-dependent increases in exon skipping, restoration of dystrophin protein expression in muscle, and sustained improvements in motor function. Specific measures included an average 8-point gain in North Star Ambulatory Assessment scores maintained from 6 months through later follow-up and a mean 96-meter improvement in the 6-Minute Walk Test. Signals of improved respiratory muscle function were noted, which is significant as respiratory decline is a major cause of morbidity in DMD. No treatment-related serious adverse events were observed in the patients or preceding nonhuman primate studies. The technological development and clinical results were published simultaneously in the journal Cell on or around June 10, 2026.

How it works

In DMD, mutations frequently shift the reading frame of the gene's messenger RNA, causing the cellular machinery to produce a non-functional or absent dystrophin protein. The LEAPER 2.0 strategy uses a circular RNA molecule (circ-arRNA) packaged in an adeno-associated virus vector chosen for its preference for muscle cells. Once inside the cell, this guide RNA targets regulatory sequences around a specific exon in the DMD pre-mRNA.

The circ-arRNA recruits endogenous ADAR enzymes to edit adenosine to inosine at splice sites, which the cell interprets as guanosine, or physically blocks spliceosome assembly. Either or both mechanisms cause the splicing machinery to skip the targeted exon (for example exon 51, relevant to approximately 13 percent of patients). This restores the open reading frame, enabling production of a truncated but functional dystrophin protein that stabilizes muscle cells. Studies in DMD monkey models demonstrated that one dose could yield dystrophin restoration and functional benefits lasting more than one year with good tolerability.

What it means for international patients

The clinical experience indicates that RNA editing via the LEAPER platform may offer a one-time intervention with durable effects for certain genetic diseases, expanding options beyond existing DMD therapies. Shanghai Children's Medical Center, where the clinical component of this research was conducted, has established international medical services to accommodate patients from abroad, including English-language support through dedicated staff and volunteer networks.

Patients from overseas interested in this or similar RNA editing approaches for DMD or other rare diseases must confirm eligibility, trial status, and any requirements directly with the hospital. Sources do not detail specific protocols for international enrollment in the LE051 program, and participation in clinical research depends on individual medical profiles, regulatory frameworks, and hospital assessment. Direct inquiry with the hospital's international department is necessary for current information.

About the hospital

Shanghai Children's Medical Center, also known as Shanghai Jiao Tong University School of Medicine Affiliated Shanghai Children's Medical Center, is a Grade III Class A tertiary pediatric specialty hospital in Shanghai. Established in 1998 with international collaboration, it serves as a National Children's Medical Center and is affiliated with Shanghai Jiao Tong University School of Medicine. It features multiple campuses in the Pudong area.

The hospital specializes in pediatric cardiology and congenital heart surgery with high annual surgical volumes, pediatric hematology and oncology (one of the largest centers), treatment of rare diseases, neonatology, and developmental pediatrics. It was the first children's specialty hospital in China to achieve JCI accreditation. It maintains an international patient department offering services to foreign families with multilingual capabilities including English.