Stoke Therapeutics, Inc. · NASDAQ:STOK

Stoke Therapeutics — Association for Research in Vision & Ophthalmology Meeting 2021

19 slides from Stoke Therapeutics's conference presentation, 2021

1. Slide 1: ASO mediated increase in OPA1 improves mitochondrial function in ADOA fibroblasts

   Antisense oligonucleotide mediated increase in OPA1 improves mitochondrial function in fibroblasts derived from patients with autosomal dominant optic atrophy (ADOA) Association for Research in Vision & Ophthalmology Meeting 2021 Aditya Venkatesh, Ph.D. Senior Scientist

2. Slide 2: Authors and disclosures

   Authors and disclosures Aditya Venkatesh1, Syed Ali1, Raymond S. Oh1, Donna Sonntag1, Zhiyu Li2, Taylor McKenty1, Brittany A. Slipp1, Robert Hufnagel2, Jeffrey Hoger1, Gene Liau1 1. Stoke Therapeutics, Bedford, MA, United States. 2. Medical Genetics and Ophthalmic Genomics Unit, National Eye Institu

3. Slide 3: Disclaimer

   Disclaimer This presentation has been prepared by Stoke Therapeutics, Inc. (“Stoke” or “our”) for informational purposes only and not for any other purpose. Nothing contained in this presentation is, or should be construed as, a recommendation, promise or representation by the presenter or Stoke or

4. Slide 4: OPA1 haploinsufficiency is the primary cause of ADOA

   OPA1 haploinsufficiency is the primary cause of autosomal dominant optic atrophy (ADOA) • ADOA is the most common inherited optic nerve disorder and is characterized by retinal ganglion cell loss • 65-90% of cases are caused by mutations in one allele of the OPA1 gene, a mitochondrial GTPase with a

5. Slide 5: Targeted Augmentation of Nuclear Gene Output

   Our compounds aim to restore protein Targeted levels by increasing protein production from the functional copy of a gene and: Augmentation of Selectively boost expression only in tissues Nuclear where the protein is normally expressed Gene Offer one drug for diseases caused by many different mutatio

6. Slide 6: Haploinsufficiency without TANGO-ASO

   Haploinsufficiency without TANGO-ASO = 50% functional protein © Copyright 2021 Stoke Therapeutics 6 NMD: non-sense mediated decay

7. Slide 7: Haploinsufficiency with TANGO-ASO

   Haploinsufficiency with TANGO-ASO ~100% Functional protein © Copyright 2021 Stoke Therapeutics 7

8. Slide 8: TANGO is ideally suited to the treatment of ocular diseases

   TANGO is ideally suited to the treatment of ocular diseases • Intravitreal injection permits diffusion throughout eye to deliver ASOs to retinal cells • Potential for long-term efficacy (up to 1 year in mouse retina) after a single intravitreal injection1 • No specialized formulation or encapsulatio

9. Slide 9: Previous preclinical data support the potential use of TANGO in ADOA

   Previous preclinical data1 support the potential use of TANGO in ADOA • ASO-mediated specific reduction in NMD exon inclusion splicing in OPA1 pre-RNA • Dose-dependent increase in total OPA1 mRNA and protein levels in vitro • Reduction in non-productive splicing and increase in OPA1 protein levels i

10. Slide 10: Primary fibroblast cells obtained from three ADOA patients

    Primary fibroblast cells were obtained from skin biopsies of three ADOA patients OPA1 mutations in diagnosed ADOA patients: • F34: c.1608+1delGTGAGG (canonical splice mutation) • F35: c.2873_2876del (frameshift mutation) • F36: c.635_636delAA (frameshift mutation) © Copyright 2021 Stoke Therapeutics

11. Slide 11: Questions addressed in the presentation

    Questions addressed in the presentation • Do the ADOA patient fibroblast lines show reduced OPA1 expression consistent with haploinsufficiency? ➢ Can TANGO ASO modify OPA1 expression in ADOA patient cells? • Is reduced OPA1 expression associated with a decrease in mitochondrial function? ➢ Can TANGO

12. Slide 12: All ADOA patient fibroblast lines show reduced OPA1 mRNA & protein levels

    All ADOA patient fibroblast lines show reduced OPA1 mRNA & protein levels ✱✱✱✱ ✱✱✱✱ A B Relative OPA1 mRNA expression ✱✱✱✱ ✱✱✱✱ 150 150 normalized to -tubulin ✱✱✱✱ ✱✱✱✱ Relative OPA1 protein 100 100 50 50 0 0 WT F34 F35 F36 WT F34 F35 F36 C Representative immunoblot of OPA1 protein expression level

13. Slide 13: TANGO ASO reduces non-productive exon inclusion and increases OPA1 mRNA

    TANGO ASO reduces non-productive exon inclusion and increases OPA1 mRNA expression in all cell lines Non-productive OPA1 mRNA Total OPA1 mRNA ✱✱✱✱ ✱✱✱✱ A Relative NMD exon inclusion B 150 Relative mRNA expression 150 ✱ ✱✱✱ ✱ ✱✱✱✱ ✱✱✱✱ ✱✱✱✱ 100 100 50 50 0 0 T: ock AS k AS k AS k 4 4 4 4 T: ock AS k

14. Slide 14: TANGO ASO increases OPA1 protein expression for all three mutations

    TANGO ASO increases OPA1 protein expression for all three mutations ✱✱✱ ✱✱✱ ✱✱ ✱ 150 OPA1 and β-tubulin protein expression normalized to -tubulin Relative OPA1 protein WT F34 F35 F36 100 Mock ASO-14 Mock ASO-14 Mock ASO-14 Mock ASO-14 OPA1 50 β-Tubulin ASO-14 produces ~35-47% increase in multiple O

15. Slide 15: Patient fibroblast cell lines show deficiencies in mitochondrial bioenergetics

    Patient fibroblast cell lines show deficiencies in mitochondrial bioenergetics ADOA patient cell lines show impaired mitochondrial bioenergetics Units are pmol/min/cells. Oxygen Consumption Rates (OCR) normalized to total cell count and plotted relative to wild-type (WT); © Copyright 2021 Stoke Ther

16. Slide 16: TANGO ASO increases mitochondrial bioenergetics in F35 patient cell line

    TANGO ASO increases mitochondrial bioenergetics in F35 patient cell line ✱✱✱✱ A B ✱✱✱✱ ✱✱✱✱ 140 140 ✱✱✱✱ ATP linked respiration 120 120 100 100 Basal OCR 80 80 60 60 40 40 20 20 ASO-14 increases 0 0 nM nM nM nM nM nM mitochondrial bioenergetics k nM nM nM nM nM nM k oc oc 20 40 60 20 40 60 20 40 60

17. Slide 17: TANGO ASO increases mitochondrial bioenergetics in F36 patient cell line

    TANGO ASO increases mitochondrial bioenergetics in F36 patient cell line ns ns A B ✱✱✱✱ ✱✱✱✱ 150 ✱✱✱✱ ✱✱✱✱ 150 ATP linked respiration 125 125 100 Basal OCR 100 75 75 50 50 25 Dose-dependent increase in 25 0 0 mitochondrial bioenergetics is k T nM nM nM oc N k NT oc 0 nM 0 nM 0 nM nM M 20 40 60 M M m

18. Slide 18: Preclinical data support TANGO as a potential disease modifying approach to treat ADOA

    Preclinical data support TANGO as a potential disease modifying approach to treat ADOA TANGO ASO reduced non-productive exon inclusion and increased total OPA1 ✓ mRNA expression in three patient fibroblast cell lines with different mutations. TANGO ASO increased expression of multiple OPA1 protein i

19. Slide 19: Questions?

    Questions? Aditya Venkatesh, Ph.D. Senior Scientist [email protected] Dawn Kalmar Chief Communications Officer [email protected] © Copyright 2021 Stoke Therapeutics 19

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