Forward-Looking Statements Statements contained in this document and any accompanying presentation regarding matters, events, statistics, or clinical or financial results that may occur in the future are "forward-looking

Ixo-vec Phase 2 Initial LUNA Safety

and Efficacy Data Q1'24 Exhibit 99.1

Forward-Looking Statements Statements

contained in this document and any accompanying presentation regarding matters, events, statistics, or clinical or financial results that may occur in the future are "forward-looking statements" within the meaning of the Private

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those set forth herein.

AAV2.7m8 capsid Promoter Aflibercept

(anti-VEGF) AAV2.7m8 capsid engineered via directed evolution for enhanced transduction carrying a coding sequence for the anti-VEGF protein aflibercept Following a one-time IVT Ixo-vec injection, transduced retinal cells become the source of

continual aflibercept production OPTIC 2x1011 vg/eye Participant with No Supplemental anti-VEGF Injections Through 3 Years Long-term data from the FIH OPTIC study demonstrate sustained efficacy outcomes through 3 years IVT injection of Ixo-vec

Ixo-vec IVT Gene Therapy is Designed to Provide Continuous Delivery of Aflibercept for Long-term nAMD Management and Preservation of Vision IVT: intravitreal; FIH: first-in-human Grishanin, R, et.al. Molecular Ther 2019; 27(1), 118-129; Khanani AM

et al. Lancet eClinical Medicine. 2024; Regillo CD. AAO Annual Meeting 2023. San Francisco, CA Baseline BCVA (ETDRS): 75 Year 3 BCVA (ETDRS): 80

Demonstrated Clinical Activity

Reduction in Treatment Burden in patients requiring > 9 annualized anti-VEGF injections: >90% reduction in anti-VEGF injections 85% and 68% of patients remain free of injections at 6 months at 2E11 and 6E10 doses Visual Acuity: maintained BCVA

at both doses Anatomic Endpoints: demonstrated stable CST at both doses Improved Safety Profile and Promising Prophylaxis: Promising local prophylactic options identified: Ozurdex + difluprednate drops led to > 90% of patients having no or

minimal inflammation (0 or 0.5+ AC cells) Inflammation (primarily AC cells) responsive to local corticosteroids per protocol; no Ixo-vec related SAEs Key Takeaways Potential Best-In-Class Activity, Improved Safety Profile and Promising Prophylaxis

for Pivotal Program Preliminary analysis of an ongoing trial, results may change.

Envisioning the Future of Treatment

for Wet AMD, Leading Cause of Blindness in Patients Over 65 Today Tomorrow Real world loss of vision3,4 One and done outpatient IVT Lifetime vision preservation Direct and indirect health-system savings 1Bright Focus Foundation. Age-Related Macular

Degeneration: Facts & Figures. 2Wong WL, et al. Global prevalence of age-related macular degeneration and disease burden projection for 2020 and 2040: a systematic review and meta-analysis. Lancet Glob Health. 2014;2:106-16.

3Holz FG et al. Br J Ophthalmol 2015; 99 (2): 220-226. 4Khanani A, et al. Ophthal. Retina 2020 Feb; 4(2):122-123. 5CMS/Office of Enterprise Data & Analytics (OEDA), January 2022. Nguyen X. Nguyen, T. Anders Olsen, Steven H. Sheingold, and

Nancy Delew. Medicare Part B Drugs: Trends in Spending and Utilization, 2008- 2021. Washington, DC: Office of the Assistant Secretary for Planning and Evaluation, U.S. Department of Health and Human Services. June, 2023. 6In 2021; based on

Department of HHS and corporate anti-VEGF revenue reports. 7Gangnon RE et al. (2015) JAMA Ophthalmol; 133 (2): 125-132. Rasmussen A. et al., (2017) Eye 31, 978-980 (2017). Wong TY, et al. (2020) Retina. 40, 599-611 Zarranz-Ventura J et

al. (2014). Ophthalmology; 121 (10): 1966-1975. 1.5M patients U.S.1,2 Up to 42% develop bilateral disease within 2-3 years of initial diagnosis7 ~200,000 new cases every year.1,2 13% of Medicare Part B cost5 $139B due to vision loss6

Lifetime injections burden 20M worldwide.1,2 Life Long IVT Injections Gene Therapy's Potential

Ixo-vec May Preserve Vision Over

Time With a Single Injection SoC curve is based on CATT, HARBOR, and 7UP extension out to 5 years, with years 5-10 modeled. Sources: Weng CY, Singh RP, Gillies MC, Regillo CD. Optimizing Visual Outcomes in Patients With Neovascular Age-Related

Macular Degeneration: the Potential Value of Sustained Anti-VEGF Therapy. Ophthalmic Surg Lasers Imaging Retina. 2023 Nov;54(11):654-659, *Potential Ixo-vec curve illustrated based on OPTIC results Khanani et al. Lancet eClinical Medicine

-- THE LANCET Discovery Science 2024. *Boulanger-Scemama E, et al. Ranibizumab for exudative age-related macular degeneration: A five year study of adherence to follow-up in a real-life setting. J Fr Ophtalmol. 2015;38:620-7. Ixo-vec

Real-world evidence Years Visual Acuity (letter change from baseline) Illustrative Long-Term Vision Outcome SoC Continuous stable aflibercept levels (4.5 years demonstrated in OPTIC) Aflibercept Levels Ixo-vec Bolus injections AND undertreatment

lead to fluctuations in anti-VEGF Aflibercept Levels Missed Injection Missed Injection Missed Injection Up to 57% STOP anti-VEGF over 5 years**

The Evolution of Wet AMD Treatment and

Potential Future Advancements Reduction in treatment burden Gain of vision on treatment initiation Laser Photocoagulation Past Present Future Verteporfin Photodynamic Therapy (PDT) 2nd Generation 4-16 weeks TKIs Axpaxli EYP-1901 CLS-AX ~6 months

Gene Therapy Ixo-vec 4D-150 ABBV-RGX-314 3 years to lifetime Prevention of significant vision loss 1st Generation 4-8 weeks + Extended durability + Preservation and/or vision gain TKI = tyrosine kinase inhibitors; 1-3 lead-in aflibercept

injections required as part of trial design.

OPTIC Data Suggest Potential

Best-in-Class Reduction in Injections, Vision Preservation > 3 Years, and Aflibercept Up to 4.5 Years *Cataract surgery Khanani et al. Lancet eClinincal Medicine - THE LANCET Discovery Science. 2024; Regillo CD. AAO Annual Meeting 2023. San

Francisco, CA OPTIC Key Takeaways Durability demonstrated with aflibercept levels to 4.5 years in the longest wet AMD IVT gene therapy dataset Highest 3-year % injection free Greatest annualized injection rate reduction 2E11 dose well tolerated

through 3 years of follow-up 53% of Patients Free of Injections Through 3 Years

Corticosteroid Prophylaxis

Supplemental Injection Criteria Difluprednate 22 wks prednisone oral 10 wks Ozurdex IVT + difluprednate after week 4 prednisone oral 10 wks Randomized 2:1 local versus local + oral Increase in CST > 75 m from BL confirmed by

the CRC OR Loss of 10 letters in BCVA from BL due to new/worsening IRF or SRF OR New vision-threatening hemorrhage due to nAMD LUNA Phase 2 Trial in Previously Treated Patients with Wet AMD Multicenter, double-masked, randomized,

parallel-group Phase 2 study Key inclusion criteria: demonstrated response to anti-VEGF therapy and under active treatment for CNV secondary to nAMD (received a minimum of 2 injections within 4 months of entry), study eye BCVA in the range of

25 - 83 ETDRS letters Study timeline and length of arrows depicted are not to scale Protocol amended early in study to include difluprednate after week 4 to match the taper in difluprednate regimens. Long-term extension ends at year five

Screening Period 2x1011 vg/eye (n=30) 6x1010 vg/eye (n=30) WEEK 52: Primary Endpoint Week 26: Interim Analysis Day 1: IVT Ixo-vec randomization Aflibercept IVT 2mg FIVE year: EXT Completion Corticosteroid prophylaxis (21 weeks post-dose)

LUNA Study Disposition (as of 15

Nov 2023) Participant Disposition Number of subjects randomized and dosed with Ixo-vec 60 Number of participants who completed Week 14 54 Number of participants who completed Week 26 26 Number of participants who discontinued after Ixo-vec dosing 2

Reason for discontinuation (not related to Ixo-vec) Death (Abdominal mesenteric mass, multiple organ failure, and septic shock - not related to study drug) Adverse event (Dementia - not related to study drug) 1 1 Patients who received at

least one injection of anti-VEGF agent in year prior to Screen Aflibercept Bevacizumab Ranibizumab Faricimab Other 43 (72%) 15 (25%) 15 (25%) 10 (17%) 1 (2%) Safety outcomes, AH aflibercept levels, BCVA, and CST current through 15Nov2023.

Supplemental anti-VEGF data current through 02Jan2024. A prespecified interim analysis will be conducted when all participants complete their 26-week study visit

LUNA Demographics and Baseline

Characteristics Demographics and Baseline Characteristics Ixo-vec 6E10 vg/eye N = 30 Ixo-vec 2E11 vg/eye N = 30 LUNA Total N = 60 OPTIC N = 30 Mean age, years (SD) 75.4 (8.2) 77.7 (7.4) 76.6 (7.8) 79.0 (7.3) Female, n (%) 16 (53%) 18 (60%) 34 (57%)

15 (50%) Race, n (%) White Asian 27 (90%) 2 (7%) 28 (93%) 2 (7%) 55 (92%) 4 (7%) 30 (100%) 0 Mean years since nAMD diagnosis in the study eye (SD) 2.9 (2.8) 2.8 (3.1) 2.8 (2.9) 3.7 (2.8) Mean annualized anti-VEGF injections in year prior to Day 1

(SD) 10.0 (1.6) 9.7 (2.5) 9.9 (2.1) 9.9 (1.9) Mean BCVA, ETDRS letters (SD) 72.9 (8.8) 71.8 (6.4) 72.3 (7.7) 65.4 (7.2) Mean CST, m (SD) 360.6 (112.0) 340.5 (119.3) 350.6 (115.2) 397.0 (137.3) Phakic lens status, n (%) 11 (37%) 11 (37%) 22

(37%) 10 (33.3%) Data cut: 15Nov2023

Compelling Injection Reduction at

6E10 and 2E11, on Track with OPTIC 91% 90% 85% 86% 95% 94% Mean Prior Annualized Injections Mean Post-Ixo-vec Annualized Injections Data cut: 02Jan2024 OPTIC 2E11 LUNA 2E11 LUNA 6E10

Compelling Injection Free Rates at

6E10 and 2E11, on Track with OPTIC 91% 90% 85% 86% 95% 94% Mean Prior Annualized Injections Mean Post-Ixo-vec Annualized Injections OPTIC 2E11 LUNA 2E11 LUNA 6E10 Injection Free 86% 68% Injection Free 87% 85% Injection Free 80% 73% Data cut:

93% Anti-VEGF Treatment Burden

Reduction Across Both Doses in Patients Needing Mean > 9 Annualized Injections Before Ixo-vec Data cut: 02Jan2024. 71% reduction of annualized injections across both doses in subset of patients who received supplemental Injections. Ixo-vec 9

Participants with 1 Injection 6 Participants with >1 Injection 93% Reduction in Annualized Anti-VEGF 75% Injection Free -1 Year 26 14 18 22 10 8 6 4 30 34 38 42 48 52 Study Week

30 30 29 30 30 29 28 23 20 13 30 30

28 30 30 29 28 23 20 12 30 30 30 30 29 29 26 21 15 12 Visual and Anatomic Outcomes in LUNA Confirm Activity Observed in OPTIC Mean CST change from baseline to last visit, m (CI) Mean Best Corrected Visual Acuity (BCVA) Over Time by Dose Mean

Central Subfield Thickness (CST) Over Time by Dose N Mean BCVA change from baseline to last visit, letters (CI) +0.5 (-2.2, 3.3) 6E10 vg/eye -1.7 (-4.5, 1.2) 2E11 vg/eye N -7.9 (-30.9, 15.0) 6E10 vg/eye -16.4 (-31.5, -1.3) 2E11 vg/eye 30 30 30 30 29

29 26 21 15 12 N N +0.2 (-4.6, 5.0) 2E11 vg/eye OPTIC (n=15) Data cut: 15Nov20323. LUNA 95% CI; OPTIC 90% CI. LUNA and OPTIC differ in study visit cadence -92.9 (-153.32, -32.55) 2E11 vg/eye OPTIC (N=15)

22 22 22 21 21 18 13 8 6 26 25 26

26 25 24 20 18 12 Stable Visual and Anatomic Control Maintained in Supplemental Injection Free Patients Mean CST change from baseline to last visit, m (95% CI) Mean Change in BCVA Over Time in Supplemental Injection Free Participants, by Dose

Mean Change in CST Over Time in Supplemental Injection Free Participants, by Dose Mean BCVA change from baseline to last visit, letters (95% CI) +2.7 (0.0, 5.4) 6x1010 vg/eye -1.2 (-4.1, 1.7) 2x1011 vg/eye -2.8 (-19.7, 14.2) 6x1010 vg/eye -14.8

(-32.1, 2.4) 2x1011 vg/eye 22 22 22 21 21 18 13 8 6 26 24 26 26 25 24 20 18 11 Data cut: 15Nov2023 N N N N

No minimum aqueous humor

aflibercept threshold for clinical benefit observed Aqueous Aflibercept Levels at Both Doses in LUNA Demonstrate Ixo-vec Therapeutic Benefit Data cut: 15Nov2023. LUNA Week 14 aflibercept levels plotted for 26 of 30 individual participants. 4 samples

across both the 2E11 and 6E10 doses had aqueous aflibercept levels (ELISA assay BLOQ: <25 ng/ml). Of these, 2 were free of injections and 2 had either 1 or 2 supplemental injections through at least week 26. LUNA revised to stop collection of AH

samples. *Participant received supplemental aflibercept injections at weeks 36, 52, 64, 68, 76, 80, 88, 92, 100, 130, 143, 156. 58% reduction in annualized anti-VEGF injections 3 years post-Ixo-vec compared to 12 months prior to Ixo-vec.

**Participant received supplemental aflibercept injections at weeks 24, 64, 72, 80, and 156. 81% reduction in annualized anti-VEGF injections 3 years post-Ixo-vec compared to 12 months prior to Ixo-vec. At three timepoints (not indicated

on plot), aflibercept levels were BLOQ. Early aflibercept levels are associated with sustained long-term protein expression OPTIC: all patients received therapeutic benefit OPTIC 2x1011 vg/eye (n=7) LUNA 2x1011 vg/eye (n=14) LUNA 6x1010 vg/eye

(n=12) Data cut: 15Nov2023 * **

Ozurdex + Difluprednate Eyedrops

Identified as Potential "Go-Forward" Regimen Ixo-vec was well-tolerated, with inflammation that was responsive to protocol-defined local corticosteroids No Ixo-vec related SAEs; Ixo-vec related AEs were all mild to moderate No

episcleritis, vasculitis, retinitis, choroiditis, vascular occlusion or hypotony Most common Ixo-vec related AEs were dose-related anterior inflammation (primarily AC cells) and anterior pigmentary changes; consistent with OPTIC 2E11 Local

prophylaxis regimens are promising Ozurdex + Difluprednate regimen resulted in > 90% of patients having no or minimal inflammation (0 or 0.5+ AC cells) Optimized prophylaxis resulted in an improved inflammatory profile versus OPTIC 2E11,

manageable with local steroids Ozurdex alone ( oral) did not provide adequate prophylaxis Oral corticosteroids showed no incremental benefit Data cut: 15Nov2023. OPTIC: Khanani et al. Lancet eClinincal Medicine - THE LANCET Discovery

Science. 2024 LUNA Preliminary Safety Summary

Ozurdex + Difluprednate Eyedrops

Identified as Potential "Go-Forward" Regimen Data cut: 15Nov2023. Cell grades as assessed by slit lamp, Grade categories are based on the Standardization of Uveitis Nomenclature (SUN) and National Eye Institute Scores for white blood

cells. No subject had more than 2+. * Mixed pigmented and non-pigmented cells; pc, pigmented cell. 1. Includes post-data cut review of outcomes in 4 individual patients. The second patient in the LUNA Vitreous Cells Heatmap had 0.5+ vitreous cells