Zeleciment basivarsen (z-basivarsen) (DYNE-101) - (ACHIEVE)

September 8, 2026: Dyne Therapeutics (NASDAQ: DYN) said it will present additional 1-year Phase 1/2 ACHIEVE data for zeleciment basivarsen (z-basivarsen/DYNE-101) in myotonic dystrophy type 1 (DM1) at the World Muscle Society meeting (oral presentation September 30, 2026) and at AANEM (poster September 30-October 1, 2026). The update will include 6- and 12-month data from a pooled ACHIEVE multiple ascending dose group (N=25-26) covering the 3.4 mg/kg Q4W, 5.4 mg/kg Q8W, and 6.8 mg/kg Q8W cohorts, including participants originally assigned placebo; 12-month data from a propensity-matched END-DM1 natural history cohort (N=41-46); and updated safety from ACHIEVE MAD participants.

Dyne also plans to disclose the mean baseline video hand opening time (vHOT) for the blinded ACHIEVE registrational expansion cohort (n=71). Topline data from the ACHIEVE registrational expansion cohort remain on track for Q1 2027. The fully enrolled cohort is intended to support potential regulatory submissions, including possible U.S. Accelerated Approval, with primary endpoint change from baseline in middle finger myotonia measured by vHOT at 6 months versus placebo.

Additional conference presentations cover the Phase 3 HARMONIA DM1 study design and Duchenne programs for zeleciment rostudirsen, including DELIVER data and the Phase 3 FORZETTO study.