Lexeo Therapeutics, Inc. · NASDAQ:LXEO
Lexeo Therapeutics — Corporate Update (October 2025)
21 slides from Lexeo Therapeutics's corporate update, Oct 7, 2025
Slide 1: Lexeo Therapeutics Announces Progress in FDA Discussions and Positive Interim Clinical Data for LX2006
Lexeo Therapeutics Announces Progress in FDA Discussions for Accelerated Approval Pathway and Positive Interim Clinical Data for LX2006 in FA Cardiomyopathy October 7, 2025 Exhibit 99.1
Slide 2: Forward Looking Statements
Forward Looking Statements This presentation contains “forward-looking statements” within the meaning of the federal securities laws, including, but not limited to, statements regarding Lexeo’s expectations and plans regarding its current product candidates and programs, including statements regardi
Slide 3: FDA Open to Earlier Co-Primary Endpoint Analysis and Pooling Data from Ongoing Phase I/II Studies
FDA Open to Earlier Co-Primary Endpoint Analysis and Pooling Data from Ongoing Phase I/II Studies of LX2006 with Pivotal Data; Potential to Accelerate BLA Submission for Accelerated Approval LVMI, Left Ventricular Mass Index; LFT, liver function tests. (1) Participant 11 6-month visit not conducted
Slide 4: Treatment for FA Cardiomyopathy is Urgently Needed
Treatment for FA Cardiomyopathy is Urgently Needed Thank you sincerely to the participants, caregivers, investigators, health care professionals and to the FA community for supporting Lexeo research
Slide 5: Cardiac Complications are the Leading Cause of Death in Friedreich Ataxia
Cardiac Complications are the Leading Cause of Death in Friedreich Ataxia Cardiac complications account for up to 80% of deaths in those with FA, with an average life expectancy of 35–40 years(1)(5) FA is a rare, progressive and devastating multisystem disease caused by a loss of function mutation i
Slide 6: LX2006 Has the Potential to Treat the Root Cause of FA Cardiomyopathy
LX2006 Has the Potential to Treat the Root Cause of FA Cardiomyopathy: The Significant Decrease in Frataxin in the Heart FXN mutation FXN Deficiency Mitochondria Functional FXN FA Cardiomyopathy LX2006 Mechanism Cardiomyocyte Transfer of FXN gene to cardiomyocytes is intended to increase frataxin le
Slide 7: LX2006 is Being Evaluated in Parallel SUNRISE-FA and Weill Cornell Trials
LX2006 is Being Evaluated in Parallel Lexeo-Sponsored SUNRISE-FA and Weill Cornell Investigator Initiated Trials SUNRISE-FA and Weill Cornell trials share a similar study design, enabling data from the two studies to be evaluated together 2 Key Inclusion Criteria 3 Key Measurements 1 Study Design &
Slide 8: Collective Regulatory Feedback Could Reduce Size and Length of Planned Pivotal Study
Lexeo Believes Collective Regulatory Feedback Could Reduce Size and Length of Planned Pivotal Study, Possibly Accelerating Overall Timeline to BLA Submission FDA open to BLA submission that includes LVMI data from ongoing Phase I/II studies pooled with new clinical data generated in planned pivotal,
Slide 9: In Phase I/II Studies, Baseline Characteristics Are Consistent with Cardiac Phenotype of FA
In Phase I/II Studies, Baseline Characteristics Are Consistent with Cardiac Phenotype of FA Cohort 1 (1.8x1011 vg/kg) Cohort 2 (5.6x1011 vg/kg) Cohort 3 (1.2x1012 vg/kg) Participant Characteristic Participant # Participant # Participant # #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #13 #17 #12 #14 #15 #16 Ge
Slide 10: Treatment with LX2006 Has Been Generally Well Tolerated to Date
Treatment with LX2006 Has Been Generally Well Tolerated to Date LFT, liver function tests. No clinically significant complement activation Minimal, transient LFT elevations after dosing; no participants above 3X upper limit of normal No signs of frataxin over-expression observed in cardiac tissue No
Slide 11: Participants with Abnormal LVMI at Baseline: Improvements Across Key Clinical Parameters
Participants with Abnormal LVMI at Baseline: Improvements Across Key Clinical Parameters at Latest Visit with Mean LVMI Reduction of 23% at 12 Months Cohort Participant # | LVMI(1) at Baseline Latest Visit (months) ∆ LVMI (g/m2) Baseline LV ∆ LWT (cm) Baseline LV ∆ Hs-TNI (pg/ml) Baseline LV C
Slide 12: Participants with Abnormal LVMI at Baseline, LVMI: Sustained or Deepening Improvement Over Time
LVMI % Change Participants with Abnormal LVMI at Baseline, LVMI: Sustained or Deepening Improvement in LVMI Over Time Cohort 1 (n=3) Cohort 2 (n=2) Cohort 3 (n=1) Note: Participant had less elevated LVMI baseline Mid- and high-dose participants maintain LVMI improvements at 12 months 6 of 6 particip
Slide 13: Supportive Endpoints: Lateral Wall Thickness and High-Sensitivity Troponin I
Participants with Abnormal LVMI at Baseline, Supportive Endpoints: LVMI Reductions Supported by Improvements in Lateral Wall Thickness and High-Sensitivity Troponin I Change from Baseline (mm) Change in LWT for Participants with Abnormal LVMI at Baseline Change in Hs-TnI for Participants with Abnorm
Slide 14: Participants with Normal or High-Normal LVMI at Baseline
Cohort Participant # | LVMI(1) at Baseline Latest Visit (months) ∆ LVMI (g/m2) Baseline LV ∆ LWT (cm) Baseline LV ∆ Hs-TNI (pg/ml) Baseline LV Cohort 1 (1.8E11 vg/kg) Participant #3 (F) Normal 24 -17.0% 53 44 +25.0% 0.8 1.0 -50.9% 108 53 Participant #4 (F) High normal 21 -3.1% 65 63 -9
Slide 15: All Participants (n=16), LVMI: Reached or Remained in Normal Range
All Participants (n=16), LVMI: All Participants Excluding Participant #10 Reached or Remained in the Normal Range for LVMI at Latest Visit Cohort 1 (n=3) Cohort 2 (n=1) Cohort 3 (n=2) LVMI (g/m2) for All Male Participants LVMI (g/m2) for All Female Participants LVMI (g/m2) Cohort 1 (n=3) Cohort 2 (n
Slide 16: All Participants (n=16), Supportive Endpoints: Lateral Wall Thickness and Troponin I
All Participants (n=16), Supportive Endpoints: Improvements in Lateral Wall Thickness and High-Sensitivity Troponin I Across Participants Regardless of Baseline LVMI Change from Baseline (mm) *Participant 10 not included in Hs-TNI chart due to scale. Values are +29% at 6M, +45% at 9M, +2,702% at 12M
Slide 17: All Participants (n=16), mFARS: Functional Improvement Over Time
All Participants (n=16), mFARS: Functional Improvement Over Time Using the Modified Friedreich Ataxia Rating Scale (mFARS) Compared to Natural History Mean Change from Baseline Change in mFARS: All Participants (n=16) FA-COMS Natural History(2) (16-40yrs Cohort) LX2006 (18-35yrs) n=16 n=16(1) n=13 n
Slide 18: All Participants (n=16), mFARS: Participants Improved or Stabilized Relative to Baseline
All Participants (n=16), mFARS: 11 of 16 Participants Improved or Stabilized Relative to Baseline at Latest Visit Change in mFARS by Dose Cohort (n=16) Change from Baseline (# points) Cohort 1 (n=6) Cohort 2 (n=6) Cohort 3 (n=4) Change in mFARS by SKYCLARYS® Utilization (n=16) Change from Baseline (
Slide 19: Previously Reported: Increased Frataxin Expression Across All Participants Evaluated
Participant #9 Previously Reported: Increased Frataxin Expression Across All Participants Evaluated at 3-Months Post Treatment Utilizing LCMS Post-Treatment FXN Levels Increased in All Participants – Measured by LCMS Participant #6 Participant #10 Participant #11 Cohort 1 (n=1) Cohort 2 (n=3) Cohort
Slide 20: Summary and Next Steps for LX2006
Summary and Next Steps for LX2006 LX2006 (AAVrh10.hFXN) has been generally well tolerated to date with no clinically significant complement activation and minimal, transient LFT elevations Sustained or deepening improvements in the majority of participants across both cardiac and neurologic measures
Slide 21: Thank you
therapeutics Thank you