Editas Medicine, Inc. · NASDAQ:EDIT
Editas Medicine — Technical Presentation (May 2022)
15 slides from Editas Medicine's technical presentation, May 19, 2022
Slide 1: A Mutation-Independent CRISPR/Cas9-Based 'Knockout and Replace' Strategy for RHO-adRP
A Mutation-Independent CRISPR/Cas9-Based ‘Knockout and Replace’ Strategy to Treat Rhodopsin-Associated Autosomal Dominant Retinitis Pigmentosa (RHO-adRP) Zoe (Chi-Hsiu) Liu, Pavlina Wolf, Ruhong Dong, Yan Huang, Diana Tabbaa, Eugenio Marco, Brian Duke, Andrea Pinilla, Asha Pant, Racheal D’Souza, Jud
Slide 2: Disclosure
Disclosure The speaker and the co-authors are employees and stockholders of Editas Medicine. 2
Slide 3: Autosomal Dominant Retinitis Pigmentosa (adRP)
Autosomal Dominant Retinitis Pigmentosa (adRP) • An inherited autosomal dominant retinal disease leading to blindness in later life • Symptoms: • Decreased night vision (nyctalopia) • Loss of peripheral vision (tunnel vision), and eventually significant decline in central vision • No approved treatm
Slide 4: Rhodopsin-Associated adRP (RHO-adRP)
Rhodopsin-Associated adRP (RHO-adRP) Rhodopsin (RHO) • A light-sensitive receptor protein involved in visual phototransduction in rods • Located in the outer segments of rods • Approximately 30% (US and UK) of adRP caused by RHO dominant mutations • Prevalence: 7,500 patients in US and 12,100 patien
Slide 5: EDIT-103: Dual AAV-Based "Knockout and Replace" Therapeutic Strategy
EDIT-103: Dual AAV-Based “Knockout and Replace” Therapeutic Strategy • Agnostic to any RHO mutation – thus will knockout any dominant gain-of-function rhodopsin mutant • Step 1: Both mutant and normal endogenous RHO will be knocked out in the treated area • Step 2: Exogenous normal RHO (resistant to
Slide 6: The RHO Promoter Restricts Gene Expression to Rod Photoreceptors in the Mouse Eyes
The RHO Promoter Restricts Gene Expression to Rod Photoreceptors in the Mouse Eyes AAV5-RHO-GFP RHO promoter GFP IS/OS ONL OPL INL Cone arrestin GFP Merge Scale bar = 20 μm AAV: adeno-associated virus; GFP: green fluorescent protein; INL: inner nuclear layer; IS/OS: inner/outer segments of photorece
Slide 7: EDIT-103 is Highly Specific: No Detectable Off-Target Editing
EDIT-103 is Highly Specific: No Detectable Off-Target Editing NO OFF-TARGET EDITING AT OFF-TARGET CANDIDATES (rhAmpSeq verification in human retina explants transduced with EDIT-103) bp: base pair; gRNA: guide ribonucleic acid; rhAmpSeq: RNase H2 enzyme-dependent amplicon sequencing
Slide 8: EDIT-103 in Humanized Mice: Rapid and Stable Gene Editing
EDIT-103 in Humanized mRhohRHO/+ Mice: Demonstrates Rapid and Stable Gene Editing Editing hRHO mRNA replacement Dose escalation • >25% of rods are edited • Editing rates increase in a dose-dependent manner Time course • Editing plateau at ~6 weeks post-injection at doses ≥ 3E12 vg/ml AAV ratio: 1:1
Slide 9: EDIT-103 in Non-Human Primates: Approximately 100% Editing in Transduced Photoreceptors
EDIT-103 in Non-Human Primates (NHPs): Approximately 100% Editing in Transduced Photoreceptors EDIT-103 (KO and Replace) x RHO promoter SaCas9 coRHO gRNA gRNA U6 U6 RHO promoter Knockout (KO only) x RHO promoter SaCas9 Stuffer gRNA gRNA U6 U6 Volume: 100 µl AAV ratio: 1:1 Time point: 13 weeks Mean (
Slide 10: EDIT-103 in NHPs: Endogenous RHO Knockdown and Over 30% RHO Replacement
EDIT-103 in NHPs: Nearly Complete Knockdown of the Endogenous RHO and Over 30% RHO Protein Replacement RHO mRNA RHO Protein Endogenous NHP RHO • 80% and 90% knockdown of endogenous NHP RHO mRNA levels were achieved at doses of 3E12 and 6E12 vg/ml, respectively. This resulted in 90% and 100% of RHO p
Slide 11: RHO Protein Expression and Retina Morphology Preserved in EDIT-103-Treated NHP Retinas
RHO Protein Expression and Retina Morphology was Preserved in EDIT-103-Treated NHP Retinas Compared with KO-Treated Retinas Vehicle KO (3E12 vg/ml) EDIT-103 (3E12 vg/ml) RPE IS/OS IS/OS IS/OS ONL ONL ONL RHO protein / Cas9 genome IS/OS IS/OS IS/OS ONL ONL ONL H&E staining AAV ratio: 1:1; Injection v
Slide 12: Retina Function Preserved in EDIT-103-Treated NHP Eyes
Retina Function Preserved in the EDIT-103-Treated NHP Eyes Compared to the KO Only Treated Eyes Retinal layers a-wave b-wave RPE 150 150 ✱✱✱ ✱✱✱ ✱ (compared to vehicle) IS/OS (compared to vehicle) % of b-wave % of a-wave a-wave ONL 100 100 OPL 50 50 INL b-wave IPL GCL 0 0 Vehicle KO EDIT-103 EDIT-10
Slide 13: Summary
Summary EDIT-103 is a one-time, high efficacy, mutation-agnostic gene medicine to permanently suppress the toxic gain-of-function associated with RHO-adRP Ex vivo: EDIT-103 shows high specificity in human retinal explants In vivo: • mRhohRHO/+ mouse: o EDIT-103 achieved rapid and stable gene editing
Slide 14: Acknowledgements
Acknowledgements Mariacarmela Allocca Asha Pant Ruhong Dong Andrea Pinilla Racheal D’Souza Mark S. Shearman Brian Duke Diana Tabbaa Georgia Giannoukos Adrian Timmers Yan Huang Pavlina Wolf Eugenio Marco Kate Zhang Judith Newmark * Alphabetical order according to last names 14
Slide 15: Thank you
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