Wednesday, September 20, 2023
Dyne Therapeutics, Inc. (Nasdaq: DYN), a company dedicated to developing transformative therapies for individuals affected by genetically driven diseases, has secured orphan drug designation from the U.S. Food and Drug Administration (FDA) for DYNE-101 for the treatment of myotonic dystrophy type 1 (DM1). DYNE-101 is currently undergoing assessment within the Phase 1/2 global ACHIEVE clinical trial, with the release of initial data on safety, tolerability, and splicing anticipated in the latter part of 2023.
Dr. Wildon Farwell, Chief Medical Officer of Dyne, emphasized the significance of obtaining FDA orphan drug designation for DYNE-101, highlighting the urgent need for new treatment options for DM1 patients. The ACHIEVE trial has been meticulously designed with the intention of it serving as a registrational study, and Dyne is eager to share the preliminary findings.
Orphan drug designation is granted by the FDA to drugs or biologics developed for the treatment, prevention, or diagnosis of rare diseases affecting fewer than 200,000 individuals in the United States. This designation affords companies certain incentives, including tax credits, exemptions from specific FDA trial-related fees, and the possibility of market exclusivity for up to seven years following drug approval.
DYNE-101 is an investigative therapy currently under evaluation in the Phase 1/2 global ACHIEVE clinical trial for individuals diagnosed with myotonic dystrophy type 1 (DM1). Comprising an antigen-binding fragment antibody (Fab) connected to an antisense oligonucleotide (ASO), DYNE-101 is engineered to facilitate targeted delivery to muscle tissue, with the objective of reducing toxic DMPK RNA in the nucleus, facilitating the release of splicing proteins, enabling normal mRNA processing and protein translation, and potentially arresting or reversing the disease. Dyne has amassed comprehensive preclinical data supporting its DM1 program, including reductions in nuclear foci, splicing corrections in patient cells, substantial reduction of toxic human nuclear DMPK RNA, correction of splicing in a novel in vivo model developed by Dyne, and the reversal of myotonia in a disease model. In non-human primates, DYNE-101 demonstrated a favorable safety profile and achieved improved muscle distribution, marked by a significant reduction in wild-type DMPK RNA. DYNE-101 has also been granted orphan drug designation by the European Medicines Agency for the treatment of DM1.
ACHIEVE represents a global Phase 1/2 clinical trial focused on the assessment of DYNE-101. The trial consists of a 24-week multiple ascending dose (MAD) randomized placebo-controlled phase, a 24-week open-label extension, and a 96-week long-term extension. Its primary endpoints center on safety and tolerability, with secondary endpoints encompassing pharmacokinetics, pharmacodynamics (including splicing changes), and evaluations of muscle strength and function. Dyne anticipates the release of initial data from the MAD placebo-controlled phase of the ACHIEVE trial, particularly in relation to safety, tolerability, and splicing, during the latter part of 2023. For additional information regarding the ACHIEVE trial, please visit https://www.clinicaltrials.gov/ (NCT05481879).
DM1 is a rare, progressive genetic disorder affecting skeletal, cardiac, and smooth muscles. This monogenic, autosomal dominant condition is caused by an abnormal trinucleotide expansion in a region of the DMPK gene, resulting in the formation of toxic RNA clusters in the nucleus and the disruption of splicing for multiple essential proteins, giving rise to a wide array of symptoms. Individuals afflicted with DM1 typically experience progressive weakening of major muscle groups, with potential repercussions for mobility, respiratory function, cardiac health, speech, digestive processes, vision, and cognitive abilities. Although it is estimated that DM1 affects over 40,000 individuals in the United States and more than 74,000 in Europe, there are currently no approved therapies capable of modifying the course of the disease.