Dyne Therapeutics Announces Positive Initial Clinical Data from ACHIEVE Trial in DM1 Patients and DELIVER Trial in DMD Patients Demonstrating Promise of the FORCE Platform in Developing Therapeutics for Rare Muscle Diseases

- In Phase 1/2 ACHIEVE Trial, DYNE-101 Demonstrated Dose-Dependent Splicing Correction, Muscle Delivery and DMPK Knockdown -

- All Evaluable Patients in the 3.4 mg/kg Cohort Treated with DYNE-101 Q4W Demonstrated Consistent Splicing Correction with a 19% Mean Improvement Across 22-Gene Panel at 3 Months -

- Improvement in Myotonia (vHOT) as well as Fatigue (MDHI) Observed in Lowest Dose ACHIEVE Cohort at 6 Months -

- In Phase 1/2 DELIVER Trial, DYNE-251 Showed 0.88% Mean Dystrophin Expression at 6 Months in 5 mg/kg Cohort Administered Monthly; Greater Than 2.5 Times Higher Dystrophin Than Reported for Weekly Administered Current Standard of Care¹-

- Favorable Safety Profile for DYNE-101 and DYNE-251 Has Supported Dose Escalation; Enrollment Complete in 5.4 mg/kg Cohort of ACHIEVE Trial and 20 mg/kg Cohort of DELIVER Trial -

- Virtual Webcast Event Today, Wednesday, January 3 at 8:00 a.m. ET -

WALTHAM, Mass., Jan. 03, 2024 (GLOBE NEWSWIRE) -- Dyne Therapeutics, Inc. (Nasdaq: DYN), a clinical-stage muscle disease company focused on advancing innovative life-transforming therapeutics for people living with genetically driven diseases, today announced positive initial clinical data from its ACHIEVE trial of DYNE-101 in patients with myotonic dystrophy type 1 (DM1) and its DELIVER trial of DYNE-251 in patients with Duchenne muscular dystrophy (DMD) who are amenable to exon 51 skipping.

“We are excited that Dyne’s first clinical data in two programs have demonstrated proof-of-concept and validated the promise of the FORCE platform in developing targeted therapeutics for rare muscle diseases. In addition to the opportunity with our co-lead programs, this clinical validation reinforces the potential of FORCE to deliver for patients in other areas, including building a global DMD franchise, addressing FSHD and exploring diseases involving the CNS,” said Joshua Brumm, Dyne’s president and chief executive officer. “The safety profiles for both DYNE-101 and DYNE-251 have supported dose escalation to a combined 10 cohorts and the administration of nearly 600 doses across both the ACHIEVE and DELIVER trials. This positions us to optimize dose and dose regimen in both trials with the goal of initiating registrational cohorts as we end 2024. We anticipate reporting data for multiple, higher dose cohorts from both trials in the second half of 2024, while continuing to pursue expedited regulatory pathways and working to help address the urgent need for therapeutics for people living with DM1 and Duchenne.”