After receiving an approval from the French health regulatory authority ANSM for its "AVANCE 1" clinical trial, SQY Therapeutics, a French biotech, announces today the start of patient enrollment for the First-In-Human administration of the investigational medicinal product SQY51, a new generation of antisense oligonucleotide designed to restore semi-functional dystrophin by skipping exon 51 of the DMD gene in a subpopulation of boys affected by Duchenne Muscular Dystrophy. 

Montigny le Bretonneux, January 25, 2023 - SQY Therapeutics, sponsor of the "Avance1" clinical trial, is pleased to announce that patient enrollment has begun, following the authorization for clinical trial by the ANSM (The French National Agency for the Safety of Medicines) in the framework of the European regulation on clinical trials of medicinal products, number EU CT 2022-500703-49-01.

"Avance1" is a monocentric Phase 1/2a study to evaluate the safety, pharmacokinetics and pharmacodynamics of SQY51 in pediatric and adult patients with a genetically confirmed diagnosis of Duchenne Muscular Dystrophy. Twelve patients (over 6 years of age) will be included in the trial. During Phase 1 of the study, which will last 13 weeks, they will all receive 6 ascending doses of SQY51 intravenously. For Phase 2a, the Phase 1 participants will be divided into 3 cohorts, each treated with a different dose of SQY51 for 32 weeks. The clinical study will be conducted at the reference center for neuromuscular diseases of the APHP Raymond Poincaré hospital in Garches (92380), France.

A series of preclinical studies indicate that SQY51 has a satisfactory safety profile and that it is capable of reaching all organs and tissues affected by the disease. As the chemistry of tricyclo-DNA has not yet been evaluated in humans, the "Avance1" trial is described as "First-In-Human" and participants exposed to the drug candidate will be monitored with the utmost care. The expected result is that SQY51 will restore dystrophin production, where needed, in order to slow down or even stop the progression of the disease in Duchenne patients affected by the exon 51 skip.

The SQY51 drug-candidate is the result of a successful collaboration between SQY Therapeutics and the UMR1179 Inserm-UVSQ research unit led by Luis Garcia at the Simone Veil Health UFR of the University of Versailles Saint-Quentin (Paris-Saclay University).

About Duchenne Muscular Dystrophy

Duchenne Muscular Dystrophy (DMD) is a genetic disease causing progressive degeneration of all muscles in the body. It is caused by abnormalities in the DMD gene (mutation), located on the X chromosome, which codes for dystrophin, a protein that is essential for the proper functioning of muscle fibers. The disease affects approximately one boy in 3500 at birth. It results in an inexorable and very disabling muscle degeneration. Boys usually lose the ability to walk between the ages of 10 and 13, and respiratory assistance is often required from adolescence onwards. Cardiac muscle damage is life threatening.

About SQY51

SQY51 is an antisense oligonucleotide designed to hybridize to a specific site on the pre-mRNA transcript of the DMD gene so that certain elements of the mutated gene are removed during mRNA maturation (exon skipping) in order to restore production of a functional truncated dystrophin. Most often, antisense oligonucleotides are small chains / sequences of 15 to 30 nucleotides (A, C, G, T bases) chemically modified to ensure their stability in the organism. SQY51 uses non-natural nucleotides of the "tricyclo-DNA" family. They have the advantage of being very stable and hybridize more efficiently with their RNA target than their natural counterparts.

About SQY Therapeutics

SQY Therapeutics is a new biotech company born from the initiative of parents of DMD boys and researchers whose objective was to implement R&D programs with a clinical focus for genetic diseases, particularly for Duchenne Muscular Dystrophy. Established as close as possible to the scientific and university-hospital environment of the UVSQ (Versailles University), SQY Therapeutics is developing, in the Saint-Quentin-en-Yvelines area, an unparalleled technological platform focused on tricyclo-DNAs with the prospect of promoting new therapeutic solutions for very disabling diseases for which the supply of care remains unsatisfactory to date.

Figure : Modeling of the SQY51 drug-compound