Neurogene Inc. · NASDAQ:NGNE
Neurogene — Investor Presentation (November 2026)
38 slides from Neurogene's investor presentation, Nov 9, 2026
Slide 1: Every Breakthrough Begins With Belief – Corporate Presentation
EVERY BREAKTHROUGH BEGINS WITH BELIEF November 2026 Corporate Presentation
Slide 2: Forward Looking Statements
Forward Looking Statements This communication contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These statements may discuss goals, intentions and expectations as to future plans, trends, events, results of operations or financial conditi
Slide 3: Our Mission and Approach
3 To develop life-changing genetic medicines for people and their families impacted by devastating neurological diseases OUR MISSION Biology-first design Precision delivery for maximum drug distribution EXACT platform for precise transgene expression Driven by patients and families in need OUR APPRO
Slide 4: NGN-401 Rapidly Advancing Towards Commercialization for Rett Syndrome
NGN-401 is Rapidly Advancing Towards Commercialization as a Potential Transformative One-Time Treatment for Rett Syndrome 4 Clear Path to Registration with Single Registrational Trial for Broadest Age Range • Key elements of Embolden registrational trial aligned with FDA, including a single trial fo
Slide 5: NGN-401 for Rett Syndrome
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Slide 6: No Approved Disease-Modifying Therapies for Rett Syndrome
6 No Approved Disease-Modifying Therapies for Rett Syndrome NGN-401 Gene Therapy Targets Root Cause The Unmet Need • Developmental regression begins at 6–18 months • Previously acquired milestones are lost • Development plateaus at age ~3 • Milestone acquisition is rare post- regression • Patients r
Slide 7: NGN-401: Designed to Be Best-in-Class Gene Therapy for Rett Syndrome
NGN-401: Purposefully Designed to Be the Best-in-Class Gene Therapy for Rett Syndrome 7 Full-length MECP2 to translate functional MeCP2 protein NGN-401 Construct Only Gene Therapy Designed to Safely Deliver Full-length Protein to Key Areas of the Brain and Nervous System to Maximize Benefit ICV deli
Slide 8: NGN-401 Clinical Program
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Slide 9: NGN-401 Phase 1/2 Trial Update: Durable Improvement Across Key Domains
NGN-401 Phase 1/2 Trial Update: Clinically Meaningful, Durable Improvement Across Key Rett Syndrome Domains, Deepens Over Time 9 30 months of continued improvement post-dose no plateau observed – no milestones lost Restarted Development Milestones acquired in a developmentally ordered stepwise seque
Slide 10: 100% of Phase 1/2 Participants Gained ≥1 Developmental Milestone
100% of Phase 1/2 participants (N=10) gained ≥1 developmental milestone and improved on CGI-I at ≥12 months Rapid onset of clinical response, with median first improvement observed at 2 months post-treatment, followed by early emergence of developmental milestones Durable, deepening treatment effect
Slide 11: NGN-401 Clinical Study Design for Treatment of Rett Syndrome
NGN-401 Clinical Study Design for Treatment of Rett Syndrome 11 Phase 1/2 converted into a single registrational study Study Design • Baseline-controlled, open-label, multicenter, single- arm pivotal trial (13 US sites) • Evaluates efficacy, safety & tolerability of one-time ICV-delivered NGN-401 Po
Slide 12: Clearly Defined Developmental Milestones
28 Clearly Defined Developmental Milestones: Derived from Natural History Study & Key Component of Primary Endpoint 12 Fine Motor/ Hand Function Gross Motor/Ambulation Communication Reached for toy Taken a drink from a cup held without assistance Used raking grasp to retrieve an object Used a pincer
Slide 13: Rigorous Embolden Milestone Criteria Applied to Phase 1/2 Data
Rigorous Embolden Milestone Criteria Evaluation Applied to Phase 1/2 Data 13 Baseline Assessment Post-Treatment Evidence Milestones documented in caregiver and CGI videos Evaluation Methods Gain from baseline scored by independent central rating using pre-specified Embolden criteria Utilizing the sa
Slide 14: Impact of NGN-401 Across Disease Severity and Ages
Evaluating the Impact of NGN-401 Across Full Spectrum of Disease Severity and Ages 14 As of data cutoff date of June 16, 2026 Pt = Participant Pediatric Cohort (N=8) Adult / Adolescent Cohort (N=2) Pt:1 Pt:2 Pt:3 Pt:4 Pt:5 Pt:6 Pt:7 Pt:8 Pt:9 Pt:10 Age at Dosing (Years) 7 4 6 7 6 4 6 8 18 14 Baselin
Slide 15: Restarting Developmental Progression Is the Goal for a One-time Gene Therapy
Restarting Developmental Progression is the Goal for a One-time Gene Therapy 15 Frankenburg et al., Denver II Technical Manual; May D, et al. J Neurodev Disord. 2024;16(1):42 Graphs for illustrative purposes only Typical Development Rett Syndrome Restarted Developmental Progression Birth Birth Birth
Slide 16: Pt:1 Developmental Milestones Gained in Ordered Progression
Pt:1 Developmental Milestones Gained in Ordered, Developmental Progression Baseline NGN-401 Restarted Developmental Progression 12 300 Taken a drink from a cup held without assistance Used a pincer grasp Used a spoon/fork to eat without assistance Transferred an object from one hand to the other Cli
Slide 17: Pt:1 Multidomain Improvements Led to New Abilities
Pt:1 Multidomain Improvements Led to New Abilities Beyond Developmental Milestones Moves more independently at home Gets in/out of bathtub, on/off furniture & up/down stairs, without help Shops with Mom, carrying the basket with both hands Joins family outings Navigates the world independently Climb
Slide 18: Pt:2 Developmental Milestones Gained in Ordered Progression
Pt:2 Developmental Milestones Gained in Ordered, Developmental Progression Months Post NGN-401 Initiation 12 240 Baseline NGN-401 Restarted Developmental Progression Fine motor Severe impairment, unable to use hands Gross motor Impaired, ataxic, help to stand Communication Severe impairment, unable
Slide 19: Pt:2 Multidomain Improvements Led to New Abilities
Pt:2 Multidomain Improvements Led to New Abilities Beyond Developmental Milestones Self-feeds and holds own drinks Bends down to pick up toys & blankets without help Turns when called, says words with meaning & follows instructions Less caregiver assistance at mealtime Moves more independently with
Slide 20: Pt:3 Multidomain Improvements Led to New Abilities
Pt:3 Multidomain Improvements Led to New Abilities Beyond Developmental Milestones 20As of data cutoff date of June 16, 2026 Requires less physical support to stand and move Follows directions in two languages and chooses the correct puzzle piece Self-feeds using a pincer grasp Uses both hands to fo
Slide 21: Pt:4 Multidomain Improvements Led to New Abilities
Pt:4 Multidomain Improvements Led to New Abilities Beyond Developmental Milestones As of data cutoff date of June 16, 2026 Turns the lights on and off herself, taking charge of her surroundings Feeds herself with a regular spoon — easier, more independent mealtimes Eats on her own Pushes herself up
Slide 22: Rapid Response Observed Post NGN-401 that Deepened Over Time
Rapid Response Observed Post NGN-401 that Deepened Over Time 22 0 3 6 9 12 15 18 24 30 36 Months post-NGN-401 Pt:1 Pt:2 Pt:3 Pt:4 Pt:5 Pt:6 Pt:7 Pt:8 Pt:9 Pt:10 Response Over Time in the Phase 1/2 Trial Total developmental milestones 47 4.7 Average milestones per participant CGI-I ≤ 3 + ≥ 1 Developm
Slide 23: Developmental Milestones Increased by Domain Over Time
Developmental Milestones Increased by Domain Over Time Post-NGN-401 Treatment NGN-401 Drove Durable Accumulation of Multidomain Milestones Across Core Domains That Matter Most to Caregivers 23 As of data cutoff date of June 16, 2026 Four previously disclosed developmental milestones included are der
Slide 24: Connecting, Self Care and Moving More Independently
Connecting with the people around them — understanding others, and making their wants and feelings known Communication Spoken in phrases Used words with meaning Pointed for something they want Waved bye-bye Responded to familiar names/words Participating in self care and increasing independence — pl
Slide 25: NGN-401 Remains Generally Well-Tolerated at the 1E15 vg Dose Level
Phase 1/2 Trial 1E15 vg Dose Total N = 10 N Events TEAEs related to NGN-401 9 68 Serious TEAEs Unrelated to NGN-401 3 6 Serious TEAEs Related to NGN-401 1 2 • All TEAEs related to NGN-401 have been Grade 1 (mild) or Grade 2 (moderate) in severity; the majority are known potential risks of AAV and ha
Slide 26: NGN-401 Phase 1/2 Data Summary (N=10)
NGN-401 Phase 1/2 Data (N=10) Developmental Milestones % of participants gained ≥1 developmental milestone at ≥12 months 100% Average milestones gained per participant 4.7 Total participants achieving: - ≥2 milestones - Response on ≥2 domains 7 out of 10 Average # milestones at: % increase from: # o
Slide 27: Dosing Completed in Embolden Registrational Trial
Dosing Completed in Embolden Registrational Trial to Support Planned BLA Submission Immunosuppression: Steroid prophylaxis during first 90 days, followed by taper Developmental Milestones • CGI-I score of ≤ 2 • Gain from baseline of at least 2 developmental milestones Single-Arm, Baseline-Controlled
Slide 28: Natural History Shows Beyond Age 3, Milestone Gains Are Rare
Natural History Study Cumulative Incidence Model Shows Beyond Age 3, Milestone Gains Are Rare with Minimal Difference at Age 6 28 % ever gained/regained: 69% | At ≥3 years: 2.5% | At ≥6 years: 0.4% Communication Example Milestone: Used words with meaning Age (years) % ever gained/regained: 46% | At
Slide 29: Phase 1/2 Responders Exceed the Bar for Success in Embolden
36% (9 of 25) Pre-Specified Minimum Response Rate for Success 80% Response Rate (8 of 10) % R es p o n d er s at 1 2 m o n th s Phase 1/2 Responders in Phase 1/2 Trial Exceed the Bar for Success Established as the Primary Endpoint in the Embolden Trial As of data cutoff date of June 16, 2026 Phase 1
Slide 30: Commercial Readiness & Key Anticipated Milestones
COMMERCIAL READINESS & KEY ANTICIPATED MILESTONES
Slide 31: Building a Strong Foundation for Commercialization
Building a Strong Foundation for Commercialization Internal CMC capabilities and manufacturing facility to produce commercial product Positioning Embolden clinical trial sites for rapid conversion to commercial sites at launch Payor research confirms strong reimbursement potential for NGN-401 Embold
Slide 32: Wholly Owned and Fully Integrated In-House AAV Manufacturing
Wholly Owned and Fully Integrated In-House AAV Manufacturing GMP Manufacturing Toxicology Batch Manufacturing Process Development Quality Assurance Quality Control Analytical Development Flexibility to manufacture AAV product at low cost Own product quality and development timelines Process developm
Slide 33: NGN-401 Poised to Transform Treatment for Rett Syndrome
Compelling Clinical Data Showed NGN-401 Restarts the Development Trajectory NGN-401 is Poised to Transform Treatment for Rett Syndrome 33 Completed Dosing in Embolden Registrational Trial Early Commercial- Readiness Underway • Chief Commercial Officer Added to Senior Leadership Team Expected to fund
Slide 34: Appendix: Additional NGN-401 Data
APPENDIX: ADDITIONAL NGN-401 DATA
Slide 35: RSGMS Phase 1/2 Data Showed Meaningful Gains in Gross Motor Function
Overview of Rett Syndrome Gross Motor Scale (RSGMS) Mean RSGMS Total-Score Gain Exceeded Natural History Normalized to One Year Rate RSGMS Phase 1/2 Data Showed Meaningful Gains in Gross Motor Function Real World Impact of RSGMS Gains: Examples of Reduced Caregiver Burden SIT TO STAND Reduces physic
Slide 36: RSHFS Phase 1/2 Data Showed Meaningful Gains in Hand Function
RSHFS Phase 1/2 Data Showed Meaningful Gains in Hand Function Validated clinical tool that assesses levels of hand function specific to Rett syndrome Increase in 1+ points is considered a meaningful gain in hand function Overview of Rett Syndrome Hand Function Scale (RSHFS) Mean RSHFS Total-Score Ga
Slide 37: ICV Delivery Achieves Greater Expression in the Brain Compared to IT-L
ICV Delivery Achieves Greater Expression in the Brain Compared to IT-L ICV = Intracerebroventricular IT-L = intrathecal lumbar ESGCT 2025 ICV route of delivery has been shown in preclinical models to have greater targeting of brain and nervous system regions underlying Rett syndrome pathophysiology
Slide 38: Rapid and Durable Expression of Full-Length MECP2 Following ssAAV Delivery
38 Rapid and Durable Expression of Full-Length MECP2 Following ssAAV Delivery in Preclinical Study, Consistent with Early Phase 1/2 Clinical Benefit Immunoblot of anti-FLAG expression in neocortex ssAAV is required to accommodate full-length MECP2 gene; ssAAV-mediated MeCP2 expression detectable by