DYN
Live News • Jun 13
Dyne Therapeutics Reaches Key Trial Enrollment for Potential New DM1 Therapy Dyne Therapeutics has completed enrollment in the registrational expansion cohort of its Phase 1/2 ACHIEVE trial studying z-basivarsen (DYNE-101) in patients with myotonic dystrophy type 1 (DM1).
The company plans to use topline data from this cohort, expected in the first quarter of 2027, to support a potential U.S. Accelerated Approval submission and subsequent Biologics License Application.
Dyne is targeting a possible U.S. launch of z-basivarsen in the first half of 2028, subject to regulatory review, and is also continuing the Phase 3 HARMONIA trial in DM1.
This enrollment milestone establishes a clear clinical and regulatory timetable for z-basivarsen, with defined data, filing and potential launch markers that investors can monitor over the next several years.
The primary risk relates to clinical and regulatory outcomes. Results from ACHIEVE and HARMONIA will be central to any approval decision, and delays or weaker-than-expected data could affect the timing and overall prospects of Dyne’s DM1 program. Announcement • Jun 04
Dyne Therapeutics, Inc. Announces Completion of Enrollment in Registrational Expansion Cohort of ACHIEVE Trial of Z-Basivarsen for Myotonic Dystrophy Type 1 (DM1) Dyne Therapeutics, Inc. announced the completion of enrollment in the registrational expansion cohort (REC) of the Phase 1/2 ACHIEVE trial of zeleciment basivarsen (z-basivarsen, also known as DYNE-101) in individuals with DM1. The registrational expansion cohort enrolled 71 participants. Topline data from the ACHIEVE REC are planned for the First Quarter 2027 to support a potential Biologics License Application (BLA) submission for U.S. Accelerated Approval in the Third Quarter 2027. Dyne intends to use data from the REC and from the already enrolled participants in the multiple ascending dose (MAD) and ongoing long-term extension portions of the ACHIEVE trial to support a potential submission for Accelerated Approval in the U.S. Dyne expects a potential U.S. launch of z-basivarsen in the first half of 2028, assuming FDA grants Priority Review and approval is received on the anticipated timeline. Dyne also continues to pursue approval pathways outside of the U.S. for z-basivarsen in DM1. ACHIEVE is a global, randomized, placebo-controlled, double-blind, Phase 1/2 clinical trial evaluating the safety, tolerability and efficacy of zeleciment basivarsen (z-basivarsen, also known as DYNE-101) in patients with myotonic dystrophy type 1 (DM1). The multiple ascending dose (MAD) portion of the study resulted in the selection of a registrational dose and regimen of 6.8 mg/kg z-basivarsen administered every eight weeks. A registrational expansion cohort to support potential regulatory submissions, including Accelerated Approval in the U.S., is fully enrolled. The primary endpoint for this cohort is the change from baseline in middle finger myotonia as measured by video hand opening time (vHOT) at 6 months, compared to placebo. Z-basivarsen is an investigational therapeutic being evaluated in the fully enrolled global Phase 1/2 ACHIEVE clinical trial and the global confirmatory Phase 3 HARMONIA clinical trial for people living with DM1. Z-basivarsen consists of an antisense oligonucleotide (ASO) conjugated to an antigen-binding fragment (Fab) that binds to the transferrin receptor 1 (TfR1) to enable delivery to muscle and the central nervous system. It is designed to deliver functional improvement in individuals living with DM1 by reducing toxic nuclear DMPK RNA to release splicing proteins and allow normal mRNA processing. Z-basivarsen has been granted Breakthrough Therapy, Orphan Drug and Fast Track designations by the U.S. Food and Drug Administration (FDA), as well as Orphan Drug designation from the European Medicines Agency (EMA) and the Ministry of Health, Labour and Welfare (MHLW) in Japan for the treatment of DM1. Myotonic dystrophy type 1 (DM1) is a rare, progressive, genetic neuromuscular disease with high morbidity and early mortality. DM1 affects approximately 40,000 people in the U.S. and approximately 55,000 people in the EU. The severity of symptoms and rate of progression varies. Symptoms can begin at any point in an affected persons life, depending on the DM1 subtype. Adult-onset DM1 symptoms typically appear between 20 to 40 years of age. DM1 is caused by mutations in the DMPK gene, leading to a widespread disruption of RNA splicing, known as spliceopathy, which drives the multi-system manifestations of the disease. People experience a broad spectrum of symptoms, including: muscle weakness throughout the body, myotonia or difficulty relaxing muscles, excessive daytime sleepiness, fatigue, dysregulated sleep, cognitive impairments, cardiac arrhythmias, respiratory issues and gastrointestinal dysfunction. Although the genetic cause of DM1 is well understood, there are currently no approved disease-modifying treatments for DM1. DYN
Live News • Jun 04
Dyne Therapeutics Reaches Enrollment Milestone in Pivotal DM1 Trial With Data Expected in 2027 Dyne Therapeutics reported completion of enrollment in the registrational expansion cohort of its Phase 1/2 ACHIEVE trial evaluating z-basivarsen in individuals with myotonic dystrophy type 1 (DM1).
The company plans to report topline data from this cohort in the first quarter of 2027, with the goal of supporting a potential Biologics License Application submission for U.S. Accelerated Approval.
Dyne outlined expectations for a potential U.S. launch of z-basivarsen in the first half of 2028, subject to Priority Review and regulatory approval on the anticipated timeline.
The key takeaway is that Dyne has reached an important operational milestone in its DM1 program, and there is now a clearer clinical and regulatory timetable in place around z-basivarsen.
Investors should keep in mind the long lead time to the next major data readout in 2027 and the regulatory uncertainties that accompany any Accelerated Approval path. 
