GUYANCOURT 23 July 2025 – SQY Therapeutics, a clinical-stage biotechnology company with a pipeline of new generation of antisense oligonucleotides from the Tc-DNA family, announced that the European Medicines Agency (EMA) has granted Orphan Drug Designation (ODD) to SQY51, an intravenous molecule targeting exon-51 of the dystrophin pre-mRNA for the treatment of patients with Duchenne Muscular Dystrophy.
SQY51 had already obtained Orphan Drug Designation from the US Food and Drug Administration (FDA) in Duchenne Muscular Dystrophy in May 2024.
SQY51 is a palmitoyl-conjugated tc-DNA antisense oligonucleotide designed to restore semi-functional dystrophin by skipping exon-51 during mRNA splicing of the DMD gene in a subpopulation of boys affected by Duchenne Muscular Dystrophy.
“We’re pleased to receive Orphan Drug Designation from the EMA, following on from the designation we have already received from the FDA,” said Luis Garcia, Special Scientific Advisor of SQY Therapeutics. “These designations reflect the significant unmet need in Duchenne Muscular Dystrophy and reinforce our belief in the potential of SQY51 to make a meaningful difference for patients and families affected by this devastating disease and concerned by the exon-51 skipping. »
SQY51 is being evaluated in the Phase 1/2a AVANCE-1 clinical trial in individuals with DMD who are amenable to exon-51 skipping. The company has completed enrollment of 12 patients in the Phase 1/2a, with data expected in 2026. Phase 1 is completed and Phase 2a is underway. SQY Therapeutics is also planning an extension phase for participants who would like to continue to benefit from the treatment.
About Orphan Drug Designation
Orphan Designation is granted to therapies intended for the treatment, prevention, or diagnosis of life-threatening or chronically debilitating diseases that affect no more than two in 10,000 people in the European Union (EU) and for which no satisfactory therapy is available. The treatment must also provide significant benefit to those affected by the condition. EMA orphan drug designation provides certain benefits, including the potential for 10 years of market exclusivity following regulatory approval in the EU, reduction in regulatory fees and a centralized EU approval process.
About SQY Therapeutics
SQY Therapeutics is a French clinical-stage biotech company founded by parents of DMD boys and researchers, with the aim of implementing clinical R&D programs for genetic diseases, primarily Duchenne Muscular Dystrophy. Located close to the scientific and university hospital environment of the University of Versailles and Paris-Saclay, SQY Therapeutics is developing a unique technological platform focused on tricyclo-DNA in Saint-Quentin-en-Yvelines, with the aim of promoting new therapeutic solutions for highly disabling diseases for which current care offerings remain unsatisfactory.
About Duchenne Muscular Dystrophy
Duchenne Muscular Dystrophy (DMD) is a genetic disease causing progressive degeneration of all muscles. It is caused by abnormalities in the DMD gene (mutations), located on the X chromosome, which codes for a protein called dystrophin, which is essential for the proper functioning of muscle fibers. The disease affects approximately one in 3,500 boys at birth. It results in relentless and highly disabling muscle degeneration. Generally, boys lose the ability to walk between the ages of 10 and 13, and respiratory assistance is often required from adolescence. Cardiac muscle involvement is life-threatening.
