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YDyne THERAPEUTICS Dyne Therapeutics Reports Second Quarter 2026 Financial Results and Recent Business Highlights July 29 , 2026 - Biologics License Application ( BLA ) for z - rostudirsen in exon 51 DMD accepted for review by FDA ; Priority Review granted ; PDUFA target action date set for January 21 , 2027- - Completed enrollment of 71 participants in registrational expansion cohort of Phase 1/2 ACHIEVE trial of z - basivarsen in DM1 ; topline data planned for Q1 2027- - Investigational New Drug ( IND ) Application cleared by FDA for DYNE - 302 in FSHD - - Expected cash runway into Q2 2028 - WALTHAM , Mass . , July 29 , 2026 ( GLOBE NEWSWIRE ) -- Dyne Therapeutics , Inc. ( Nasdaq : DYN ) , a clinical - stage company focused on delivering functional improvement for people living with genetically driven neuromuscular diseases , today reported financial results for the second quarter of 2026 and recent business highlights . " We continue to make significant progress as we execute on our goal of delivering functional improvement for people living with genetically driven neuromuscular diseases , " said John Cox , president and chief executive officer of Dyne . " The FDA's acceptance of our BLA for z - rostudirsen marks an important milestone for individuals living with DMD amenable to exon 51 skipping and a defining step in Dyne's evolution toward becoming a commercial - stage company in the near future . " " Across our portfolio , we have achieved key clinical and regulatory milestones , including completion of enrollment in the registrational expansion cohort of ACHIEVE , initiation of the global confirmatory Phase 3 HARMONIA and FORZETTO trials , and FDA clearance of our IND for FSHD , underscoring the breadth of opportunity enabled by our FORCE ™ platform . With a potential U.S. approval of z - rostudirsen in January 2027 , we are investing in the capabilities needed to support patients , execute successfully as a commercial organization and maximize long - term shareholder value . " Zeleciment rostudirsen ( z - rostudirsen , also known as DYNE - 251 ) in DMD ( Duchenne muscular dystrophy ) Phase 3 FORZETTO trial underway • Dyne initiated the global confirmatory Phase 3 FORZETTO trial of z - rostudirsen in May 2026. Dyne has aligned with the U.S. Food and Drug Administration ( FDA ) on the Phase 3 trial design and protocol , which was presented at the 19th International Congress on Neuromuscular Diseases ( ICNMD 2026 ) . Key milestones for z - rostudirsen • Dyne's BLA was accepted for review by the FDA in July 2026 , with Priority Review granted ( Prescription Drug User Fee Act ( PDUFA ) target action date set for January 21 , 2027 ) . • Dyne continues to expect a potential U.S. launch of z - rostudirsen in Q1 2027 , assuming approval is received on the anticipated timeline . • Dyne also continues to pursue approval pathways outside of the U.S. for z - rostudirsen in patients with DMD who are amenable to exon 51 skipping . • In addition to z - rostudirsen , Dyne is advancing four development candidates ( DYNE - 253 , DYNE - 245 , DYNE - 244 and DYNE - 255 ) for the potential treatment of DMD amenable to skipping of exons 53 , 45 , 44 , and 55 , respectively . Zeleciment basivarsen ( z - basivarsen , also known as DYNE - 101 ) in DM1 ( myotonic dystrophy type 1 ) Clinical trial execution progress • Dyne completed enrollment of 71 participants in the registrational expansion cohort ( REC ) of ACHIEVE in June 2026 . • Dyne began dosing participants in the global confirmatory Phase 3 HARMONIA trial of z - basivarsen in July 2026 . Key milestones for z - basivarsen • Topline data from the ACHIEVE REC are planned for Q1 2027 to support a potential BLA submission for U.S. Accelerated Approval in Q3 2027 .