Dyne Therapeutics (DYN) Guggenheim Securities Inaugural Healthcare Innovation Conference summary

Program updates and clinical progress

• Advancing neuromuscular programs in DM1 and DMD, both targeting accelerated approval pathways.

• ACHIEVE trial for DM1 is registrational, with IND approved and higher dose data (6.8 mg/kg) expected in six months; 12-month data for 5.4 mg/kg due in early January.

• No dose limitations in the ACHIEVE study; strategy enabled rapid dose escalation outside the US before FDA engagement.

• 5.4 mg/kg dose showed a 27% mean splicing improvement, considered a strong result; safety at 5.4 and 6.8 mg/kg has been excellent.

• DMD program moving forward with 32-patient registration cohort at 20 mg/kg, based on strong functional benefit and manageable safety profile.

Regulatory and data strategy

• FDA has accepted splicing as a surrogate endpoint for DM1, with functional or PRO correlation required; regulatory clarity achieved.

• Registration cohort dose for DM1 will be locked in after upcoming data; phase three will confirm additional endpoints.

• Dystrophin expression is the primary endpoint for DMD accelerated approval, with functional data (SV95C) supporting the case.

• EMA in Europe values functional endpoints like SV95C for DMD; conditional marketing authorization being pursued.

• Additional exons for DMD are in preclinical development, with plans to accelerate if Exon 51 is successful.

Safety and patient outcomes

• Over 700 doses administered in each of DMD and DM1 programs, with a strong safety profile and no new SAEs beyond previously reported cases.

• Safety at higher doses and longer follow-up remains consistent; no material changes observed.

• Functional improvements in DMD patients observed, with some exceeding minimal clinical endpoints.

• CNS effects and patient-reported outcomes (PROs) are being measured, including fatigue and sleepiness, with long-term follow-up planned.