Dyne Therapeutics, Inc. · NASDAQ:DYN

Dyne Therapeutics — 2024 AAN Annual Meeting

11 slides from Dyne Therapeutics's conference presentation, Apr 15, 2024

  1. Slide 1: Initial Data from the DELIVER Trial of DYNE-251 in Males with DMD Mutations Amenable to Exon 51 Skipping

    Initial Data from the DELIVER Trial of DYNE-251 in Males with DMD Mutations Amenable to Exon 51 Skipping Perry Shieh1, Craig Campbell2, Nicolas Deconinck3, Liesbeth De Waele4, Kevin Flanigan5, Michelle Lorentzos6, Han Phan7, Chris Mix8, Soma Ray8, Dazhe Wang8, Wildon Farwell8, Ashish Dugar8, Maria L

  2. Slide 2: Disclosures

    Disclosures • Consulting: Sarepta, Solid, Dyne, Biogen, Genentech, Novartis, Astellas, Solid, Sanofi, Alexion, Argenx, CSL Behring, Grifols, UCB • Research Grants: Sarepta, Solid, PTC, Dyne, Biogen, Genentech, Novartis, Astellas, Avidity, AMO Pharma, Abcuro, Sanofi • DYNE-251 is an investigational m

  3. Slide 3: DMD Is Caused by Mutations in the DMD Gene

    DMD Is Caused by Mutations in the DMD Gene • Duchenne muscular dystrophy (DMD) is caused • 80% of deletions occur in two hot spot regions7: by mutations in the DMD gene which results in ▪ Exons 45 to 55 (70%) greatly reduced production of dystrophin protein, ▪ Exons 2 to 20 (14%) essential for muscl

  4. Slide 4: DYNE-251 Is Designed to Leverage TfR1 to Deliver Exon 51-Skipping PMO to Affected Muscle in DMD

    DYNE-251 Is Designed to Leverage TfR1 to Deliver Exon 51- Skipping PMO to Affected Muscle in DMD PMO Linker Cell membrane Fab DYNE-251 TfR1 Nucleus PMO Reading frame disrupted (deletion of exons 48-50) Dystrophin Exon 47 Exon 51 Exon 52 pre-mRNA Endosome Splicing Dystrophin Exon 47 Exon 52 mRNA Read

  5. Slide 5: DELIVER: Phase 1/2 Clinical Trial to Evaluate DYNE-251 in Patients with DMD

    DELIVER: Phase 1/2 Clinical Trial to Evaluate DYNE-251 in Patients with DMD Global, Randomized, Placebo-Controlled Trial Evaluating DYNE-251 in Ambulant and Non-Ambulant Male DMD Patients (4-16 Years) with Mutations Amenable to Exon 51 Skipping Therapy Primary Endpoints Registrational Cohort • Safet

  6. Slide 6: DYNE-251 Safety Profile Is Favorable to Date

    Safety Exon 51 Skipping Dystrophin by WB PDPF DYNE-251 Safety Profile Is Favorable to Date Summary of Treatment Emergent Adverse Events (TEAEs) – Most TEAEs Were Mild or Moderate Placebo-Controlled Period 1 • 1 serious TEAE unrelated to study drug Participants with ≥1 TEAE – n (%) ▪ Dehydration due

  7. Slide 7: DYNE-251, Dosed Monthly, Showed Increase in Percent Exon Skipping at 6 Months

    Safety Exon 51 Skipping Dystrophin by WB PDPF DYNE-251, Dosed Monthly, Showed Increase in Percent Exon Skipping at 6 Months DYNE-251: 5 mg/kg Q4W for 6M 30 mg/kg PMO over 6M Eteplirsen: 30 mg/kg Q1W for 6M 720 mg/kg PMO over 6M 0.80 Exon 51 Skipping (%) (SEM)1 1.2 0.8 0.90 0.40 0.59 0.4 0.02 0.19 0.

  8. Slide 8: DYNE-251, Dosed Monthly, Showed Increase in Percent Dystrophin at 6 Months

    Safety Exon 51 Skipping Dystrophin by WB PDPF DYNE-251, Dosed Monthly, Showed Increase in Percent Dystrophin At 6 Months DYNE-251: 5 mg/kg Q4W for 6M 30 mg/kg PMO over 6M 0.28 1.2 Eteplirsen: 30 mg/kg Q1W for 6M 720 mg/kg PMO over 6M MHC Normalized Dystrophin 1.0 (% Normal) (SEM)1 0.8 0.88 0.6 0.60

  9. Slide 9: DYNE-251, Dosed Monthly, Showed Increase in Percent Dystrophin Positive Fibers (PDPF) at 6 Months

    Safety Exon 51 Skipping Dystrophin by WB PDPF DYNE-251, Dosed Monthly, Showed Increase in Percent Dystrophin Positive Fibers (PDPF) At 6 Months DYNE-251: 5 mg/kg Q4W for 6M 30 mg/kg PMO over 6M 19.8 35 Eteplirsen: 30 mg/kg Q1W for 6M 720 mg/kg PMO over 6M Percent Dystrophin-Positive Fibers 30 10.7 2

  10. Slide 10: Summary

    Summary • DYNE-251 consists of an exon 51-skipping PMO conjugated to a TfR1-targeting Fab designed to deliver increased levels of PMO to muscles. ▪ DYNE-251 leverages TfR1 biology to enable receptor-mediated muscle delivery. • DELIVER is an ongoing, randomized, placebo-controlled global trial of DYN

  11. Slide 11: Acknowledgements

    Acknowledgements DELIVER participants and their families UNITED KINGDOM Rajesh Karuvattil Alder Hey Children's Hospital Michela Guglieri Royal Victoria Infirmary Anne-Marie Childs BELGIUM CANADA Leeds Teaching Hospitals NHS Trust Craig Campbell Nicolas Deconinck London Health Sciences Centre UZ Gent

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