Lexeo Therapeutics, Inc. (LXEO) Business

Item 1. Business.

Overview

We are a clinical stage genetic medicine company dedicated to reshaping heart health by applying pioneering science to fundamentally change how cardiovascular diseases are treated. We are advancing a portfolio of therapeutic candidates that take aim at the underlying genetic causes of conditions, including Friedreich ataxia, or FA, cardiomyopathy, plakophilin-2, or PKP2, arrhythmogenic cardiomyopathy, and other devastating diseases with high unmet need.

Our most advanced cardiovascular product candidate, LX2006 for the treatment of FA cardiomyopathy, is currently being evaluated in SUNRISE-FA, our ongoing Phase 1/2 clinical trial and in a Cornell investigator-initiated trial. In October 2025, we reported positive interim clinical data demonstrating an encouraging safety profile and evidence of meaningful cardiac and functional benefit. Further, interim clinical data presented in a late-breaker presentation at the American College of Cardiology (ACC) Annual Meeting in March 2026 continue to show sustained or deepening improvements across both cardiac and neurologic measures of FA. In February 2026, we submitted the final registrational trial design and statistical analysis plan for the SUNRISE-FA 2 study to the U.S. Food and Drug Administration (FDA) following a Type B meeting. We expect to receive final feedback from the FDA in the second quarter of 2026 and plan to initiate a registrational study in the first half of 2026.

Our second most advanced cardiovascular product candidate, LX2020 for the treatment of arrhythmogenic cardiomyopathy, or ACM, caused by mutations in the PKP2 gene, referred to as PKP2-ACM, is currently being evaluated in HEROIC-PKP2, an ongoing Phase 1/2 clinical trial. In January 2026, we announced positive interim data from the HEROIC Phase 1/2 clinical trial. Across dose cohorts, LX2020 was generally well tolerated and led to robust transduction, increased PKP2 protein expression, and clinically meaningful improvement or stabilization in measures of arrhythmia burden in the majority of participants. We plan to share additional safety and clinical efficacy data for LX2020 in the fourth quarter of 2026, once all participants in the high dose cohorts reach at least twelve months of follow up.

Each of our gene therapy candidates utilizes the vector construct, dose and route of administration that we believe will result in the most favorable biodistribution and safety profile for our product candidate for each disease. Our most advanced programs use the AAVrh10 vector due to its high transduction efficiency in myocardial cells, potential for lower toxicity given the opportunity to utilize lower doses compared to other well-established AAV serotypes, and low pre-existing immunity.

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Our pipeline

Utilizing a stepwise, capital-efficient development approach, we are leveraging early proof-of-concept functional and biomarker data to advance a deep and diverse pipeline of cardiovascular programs for larger-rare and prevalent indications. We retain exclusive worldwide development and commercialization rights to all of our product candidates and programs.

We are developing a number of disease-modifying gene therapy candidates to treat larger-rare cardiovascular diseases that have high unmet need and no approved treatments that address the underlying genetic cause of the disease. These programs include:

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LX2006 is an AAVrh10-based gene therapy candidate designed to intravenously deliver a functional frataxin, or FXN, gene for the treatment of FA cardiomyopathy, which is the most common cause of mortality in patients with FA and affects approximately 5,000 patients in the United States. LX2006 is designed to promote the expression of the protein frataxin to restore normal mitochondrial function and energy production in myocardial cells. LX2006 has received Rare Pediatric Disease, Orphan Drug, Fast Track, Regenerative Medicine Advanced Therapy (RMAT), and Breakthrough Therapy designations from the FDA, and Orphan Medicinal Product designation from the European Commission. LX2006 has also been selected by the FDA to participate in its Chemistry, Manufacturing, and Controls (CMC) Development and Readiness Pilot (CDRP) program, which is intended to facilitate expedited CMC development of investigational therapies with expedited clinical development timeframes via an increased level of communication with the FDA on CMC development.

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LX2020 is an AAVrh10-based gene therapy candidate designed to intravenously deliver a functional PKP2 gene to cardiac muscle for the treatment of PKP2-ACM. PKP2 mutations are associated with approximately 75% of all genetic cases of ACM, and we estimate they affect approximately 60,000 patients in the United States. PKP2 mutations can cause replacement of heart muscle with fibrotic tissue and fatty deposits and severe abnormal heart rhythms, or arrhythmias, that cause cardiac dysfunction and can result in sudden cardiac death. LX2020 is designed to increase desmosomal PKP2 protein levels, reassemble desmosomes and restore myocardial cell function. LX2020 has received Fast Track and Orphan Drug designations from the FDA and Orphan Medicinal Product designation from the European Commission.

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LX2021 is a gene therapy candidate we are developing to intravenously deliver the coding sequence for the functional connexin 43, or Cx43, protein for a group of inherited cardiac muscle disorders associated with a high risk of sudden death, including ACM and certain forms of dilated cardiomyopathy. We believe restoring the Cx43 protein can potentially treat multiple genetic causes of ACM because the cardiac loss of Cx43 is a molecular deficit generally observed in all ACM patient populations. Our LX2021 program is initially targeting Desmoplakin, or DSP, cardiomyopathy, a distinct form of ACM as well as a certain form of dilated cardiomyopathy, with a prevalence that may be as high as 4% of all inherited dilated cardiomyopathies and 4% of all ACMs, impacting approximately 30,000 to 35,000 patients in the United States.

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LX2022 is a gene therapy candidate we are developing to intravenously deliver a functional TNNI3 gene to myocardial cells to treat a distinct form of hypertrophic cardiomyopathy, or HCM, due to mutations in the TNNI3 gene. Mutations in the TNNI3 gene often result in left ventricular hypertrophy and restrictive cardiomyopathy, leading to arrhythmias and heart failure. With an estimated prevalence of 1 in 500 people in the United States, HCM is one of the most common forms of genetic cardiomyopathy and is caused by mutations that affect the cardiac sarcomere in approximately 75% of cases. It is estimated that as many as 25,000 patients in the United States and 34,000 patients in the European Union are affected by HCM caused by mutations in the TNNI3 gene.

Additionally, we are seeking business development opportunities for our portfolio of candidates targeting APOE4-associated Alzheimer's disease, including LX1001 which has completed a Phase 1/2 clinical trial.

Our Approach

Our technology approach

Our most advanced programs use the AAVrh10 vector due to its high transduction efficiency in myocardial cells, higher ratio of cardiac to liver biodistribution, potentially lower toxicity given the ability to utilize lower doses, compared to other well-established AAV serotypes, and lower pre-existing immunity. The AAVrh10 vector has been shown to be capable of transducing myocardial cells based on preclinical research and ongoing clinical studies. We believe these results demonstrate that among currently available, commonly used serotypes, AAVrh10 is an efficient vector for delivery and expression of transgenes for the treatment of the cardiovascular diseases that we are currently targeting. We have observed organ-specific biodistribution advantages for our AAVrh10 vector compared to AAV9, a well-known serotype that has been evaluated in several clinical trials, including one cardiovascular clinical trial. For example, we have observed vector distribution of AAVrh10 in cardiac tissue of non-human primates, or NHPs, that is two times greater than for AAV9. Additionally, our preliminary studies in Yucatan minipigs have shown that AAVrh10 has approximately 1.5 times greater biodistribution in the heart than AAV9. In addition, preclinical studies conducted by Weill Cornell Medical College, or Weill Cornell Medicine, have demonstrated that systemic administration of AAVrh10 promotes a ratio of cardiac-to-liver biodistribution that is more favorable than what is known of other commonly used vector serotypes.

Our disease area strategy

Our cardiovascular gene therapy programs are designed to have the following characteristics:

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Indications that may be effectively treated by gene therapy. We select targets that correspond to populations with a specific genetic profile and clearly defined disease phenotype.

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Indications with the potential to demonstrate early evidence of meaningful clinical benefit. We pursue clearly defined biomarkers and functional endpoints that can provide early proof-of-mechanism and inform clinical development decisions, including the potential to seek accelerated approval pathways.

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Present opportunity to address high unmet medical need. We are focused on genetically defined cardiovascular diseases where there are no currently approved treatments or where we believe our therapeutic candidates will have a meaningful improvement relative to existing standards of care.

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Significant market opportunity. We pursue indications with significant commercial opportunities beyond those typically associated with gene therapy companies targeting rare monogenic diseases.

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Targets that have established proof-of-concept. We have leveraged our relationships with academic institutions to in-license product candidates with established proof-of-concept in relevant preclinical models that closely resemble the clinical phenotype we are pursuing.

Our manufacturing approach

We are developing gene therapy candidates for larger-rare and prevalent disease patient populations that require a high-quality process that can produce vectors in relatively large quantities while utilizing traditional biologics manufacturing infrastructure. We utilize a baculovirus/Sf9 expression system to manufacture our gene therapy candidates. Our manufacturing platform is designed to infect Sf9 cells at high densities in suspension cell culture with both an AAVrh10 and baculovirus containing the transgene. The output is coupled with a chromatography- based purification process which allows for efficient AAV purification, resulting in higher yields and fewer empty AAV capsids than traditional plasmid HEK adherent cell culture approaches.

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We believe our manufacturing process enables us to efficiently pursue our goal of targeting larger-rare and prevalent patient populations. Historically, manufacturing challenges, largely driven by the quantity of vector required to pursue large commercial opportunities have limited the utility of gene therapy for large patient populations. We believe our proprietary Sf9 baculovirus process will allow us to produce vectors at the necessary scale to support the patient populations we are targeting at a cost-of-goods profile similar to what the pharmaceutical marketplace has seen with biologics. To date, we have developed a highly reproducible and scalable 200L GMP AAV production process using the Sf9-baculovirus system, which does not require costly plasmids. Purification is also a straightforward 2-column process. The overall process delivers over 1E15 vg/L of purified AAVrh.10 product that contains less than 25% empty capsids.

In May 2025, we presented new data at the 28th American Society of Gene & Cell Therapy (ASGCT) Annual Meeting on AAV manufacturing optimization via our Sf9-baculovirus process. Data presentations reviewed the high purity and potency of our yields with improved scalability of production and reduced cost.

In October 2025, we shared CMC data for LX2006, which were submitted to the FDA to support analytical comparability between the HEK293 manufacturing process and the Sf9-baculovirus manufacturing platform. These data demonstrate similar frataxin expression in vitro between the two processes as measured by a quantitative relative potency assay in cardiomyocytes. In November 2025, the FDA approved this analytical comparability report establishing comparability between LX2006 HEK293 and Sf9 manufacturing processes, endorsing use of the optimized, Sf9 final commercial manufacturing process for LX2006 in the planned pivotal study and clearing comparability requirements to begin dosing patients.

In March 2026, we conducted an initial CMC Development and Readiness Program meeting with the FDA for LX2006, during which the agency reiterated its support for a flexible validation approach including potential for reduced process performance qualification runs and concurrent process validation. We are proceeding with validation and commercial manufacturing readiness activities to support the Biologic License Application (BLA) submission for LX2006.

Based on our approach, we expect that our existing partnerships can supply material for all of our currently ongoing and planned clinical trials as well as potential commercial production of some of our programs. We will own the intellectual property created by our manufacturing process development activities or have the ability to license it and will maintain the option to transfer the process to other CDMOs in the future and/or to our own potential facility to ensure ongoing redundancy and reliability.

Our cardiovascular gene therapy programs

LX2006 for the treatment of FA cardiomyopathy

Overview of FA

FA is a genetic, progressive, and degenerative multi-system disorder with a prevalence of 1:50,000 or approximately 5,000 people in the United States. It is estimated that approximately 80% of these patients will develop FA cardiomyopathy. FA is caused by a mutation in the FXN gene that disrupts the normal production of the protein frataxin, which is critical to the function of mitochondria in a cell and to the maintenance of cardiac function. The most common FA phenotype presents with significantly reduced frataxin levels compared to healthy individuals, however levels of frataxin in the cardiac tissue of FA patients is unknown. The frataxin deficiency in the mitochondria of myocardial cells in FA patients causes disruption of normal iron-sulfur cluster biosynthesis leading to mitochondrial dysfunction and deficient energy production.

The neurologic disease and cardiac disease are two distinct manifestations of FA. The disease is inherited in an autosomal recessive manner, where both inherited genes are abnormal, and symptoms usually begin in childhood. Absence of fully functional frataxin leads to damage to peripheral nerves and the parts of the brain that control movement and balance, leading to neurological symptoms that include impaired muscle coordination, or ataxia, that worsen over time. Initial symptoms may include unsteady posture, frequent falling, and progressive difficulty in walking due to impaired ability to coordinate voluntary movements. Affected individuals often develop slurred speech, hearing loss, scoliosis, diabetes, characteristic foot deformities, and an irregular curvature of the spine. The typical age of onset of neurological symptoms is five to 15 years old. As the disease progresses, patients typically experience various heart conditions, including thickening of the heart muscle, or hypertrophic cardiomyopathy, and arrhythmias. Hypertrophic cardiomyopathy, fibrosis, heart failure and arrhythmias are the cause of death in approximately two-thirds of FA patients. Typical onset of the cardiac disease is at 15 to 30 years old.

By the time the cardiac disease of FA emerges, the neurologic disease is generally significantly advanced and may not be amenable to gene therapy. There are currently no approved treatments for the cardiac manifestations of FA. Skyclarys, the only approved treatment for FA, is an Nrf2 activator which targets only the CNS component of the disease. As a result, patients with FA have significant unmet need for a therapy to treat cardiovascular complications associated with the disease.

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Our approach: LX2006

We are developing LX2006 as an AAVrh10-based gene therapy delivered intravenously for the treatment of FA cardiomyopathy. LX2006 is designed to deliver the FXN gene under the transcriptional control of the CAG promoter, a strong synthetic promoter frequently used in viral vectors. LX2006 utilizes AAVrh10 based on its favorable cardiac affinity and vector distribution profile observed in preclinical studies, as compared to AAV9. LX2006 is designed to transfer the FXN gene to myocardial cells and increase frataxin levels in the mitochondria. The increase in frataxin levels in the mitochondria is intended to restore mitochondrial function and energy production in cardiac myocytes.

Lexeo-sponsored LX2006 clinical development and trial design

LX2006 is currently being evaluated in an ongoing, multi-site Phase 1/2 clinical trial, or SUNRISE-FA, in patients with FA cardiomyopathy. SUNRISE-FA is a first-in-human, 52-week, dose-ascending, open-label trial of LX2006 in patients who have FA cardiomyopathy. LX2006 is administered as a one-time intravenous infusion with prednisone utilized for immune suppression. The trial consists of three dose cohorts. The cohort 1 dose level is 1.8×1011 vg/kg, the cohort 2 dose level is 5.6×1011 vg/kg, and the cohort 3 dose level is 1.2×1012 vg/kg. There is a long-term follow-up for patients who receive LX2006 to monitor ongoing safety for a total of five years, per FDA requirement.

Cardiac biopsy results from SUNRISE-FA trial

In April 2025, we provided an interim clinical update, which included frataxin protein expression from eight participants in SUNRISE-FA that had undergone cardiac biopsies. These data demonstrated increase in frataxin protein expression versus baseline at three months in all participants as measured by liquid chromatography-mass spectrometry, or LCMS. Dose-dependent increases were observed across cohorts on average, with 115% mean increase in the high-dose cohort 3 (n=4). To our knowledge, SUNRISE-FA is the first clinical trial to evaluate frataxin levels in the target organ of FA cardiomyopathy patients.

Increased frataxin expression across all participants evaluated at 3-months post treatment

Additional ongoing clinical trial of AAVrh10.hFXN (LX2006 at Lexeo)

AAVrh10.hFXN, which we refer to as LX2006, is currently being evaluated in an additional ongoing investigator-initiated, single-site clinical trial conducted by Weill Cornell Medicine (NCT05302271). Both the Weill Cornell investigator-initiated clinical study and our SUNRISE-FA clinical study use drug product manufactured at Weill Cornell Medicine utilizing the same process with identical doses in each study’s cohort 1 and cohort 2. In April 2024 we announced a license agreement with Cornell University for intellectual property rights including current and future clinical data from the ongoing Weill Cornell Medicine investigator-initiated trial of LX2006.

Cardiac biomarker data from ongoing clinical trials of LX2006

In October 2025, we provided an interim clinical update, which included baseline characteristics and safety data from the 17 treated participants across the two studies, and clinical efficacy data from the 16 participants who had reached at least six months follow-up as of that time. These data showed sustained or deepening improvements in the majority of participants across both cardiac and neurologic measures of FA.

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Improvements in LVMI among participants with abnormal baseline LVMI (n=6). Five of six participants achieved 10% by 12-month visit or sooner and six of six participants achieved LVMI measurements within the normal range as of latest visit. A 18% mean improvement in LVMI was observed at 6-month visit and a 23% mean improvement in LVMI was observed at 12-month visit, exceeding 10% FDA-aligned threshold for pivotal study. In the mid- and high-dose cohorts (n=3), a 28% mean improvement in LVMI was observed at 6-month visit and a 33% mean improvement in LVMI was observed at 12-month visit, suggesting dose-dependent improvement. Among participants with normal baseline LVMI (n=10), the majority demonstrated LVMI improvement or stabilization over time.

Participants with abnormal LVMI at baseline, LVMI % change

Improvements in secondary cardiac biomarkers. Fourteen of sixteen participants achieved 25% reduction in high-sensitivity troponin I from baseline at latest visit. Fourteen of sixteen participants achieved reduction or stabilization in LWT from baseline at latest visit.

All participants, improvements in LWT and high-sensitivity troponin I

Improvements in mFARS as demonstrated by a 2.0-point mean improvement from baseline at latest visit across all participants. Eleven of sixteen participants achieved reduction or stabilization in mFARS from baseline at latest visit.

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All participants, functional improvement over time using mFARS

In March 2026, we shared updated interim clinical data for LX2006 at the ACC Annual Meeting. Phase 1/2 interim clinical data presented at the ACC Annual Meeting continue to show sustained or deepening improvements across both cardiac and neurologic measures of FA, including statistically significant improvement in mean mFARS scores for LX2006-treated participants compared to a propensity-matched control cohort from the UNIFAI natural history study.

Safety profile of LX2006 from ongoing clinical trials of LX2006

Treatment with LX2006 has been generally well tolerated with no Grade 3 treatment-related SAEs to date, no clinically significant complement activation, minimal, transient liver function test (LFT) elevations, and no signs of frataxin over-expression observed in cardiac tissue. One previously disclosed, possibly treatment-related Grade 2 event of asymptomatic myocarditis observed one year after dosing. No participants discontinued from either study.

Regulatory Updates

In July 2025, we announced Breakthrough Therapy designation based on interim clinical data from Phase 1/2 trials showing clinically meaningful improvements in cardiac biomarkers and functional measures. We also announced that LX2006 was selected for FDA Chemistry, Manufacturing, and Controls Development and Readiness Pilot (CDRP) program, created to facilitate CMC registrational readiness and support faster patient access.

In October 2025, in response to our questions regarding the possibility of a faster path to a Biologics License Application, or BLA, the FDA indicated openness to a BLA submission for accelerated approval that includes clinical data from the ongoing Phase 1/2 studies of LX2006 pooled with new clinical data to be generated in the planned pivotal study. The FDA also previously agreed to evaluate the co-primary endpoint of LVMI at a time point earlier than 12 months. Collectively, we believe this regulatory feedback has the potential to reduce the size and length of the planned pivotal study, possibly accelerating the overall timeline to BLA submission.

In February 2026, we submitted the final registrational trial design and statistical analysis plan for the SUNRISE‑FA 2 study to the FDA following a Type B meeting. The proposed open-label study is generally consistent with previously communicated guidance on key design elements, such as study size, duration, patient population, and the LVMI primary endpoint, and incorporates FDA feedback on minimizing bias, including physician selection bias of study participants. We expect to receive final feedback from the FDA in the second quarter of 2026 and plan to provide a more detailed update at that time. Initiation of the SUNRISE-FA 2 study is expected in the first half of 2026.

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LX2020 for the treatment of ACM caused by PKP2 mutations

Overview of ACM

ACM is a genetic heart disease primarily characterized by myocardial cell loss and the replacement of heart muscle with fibrotic tissue and fatty deposits. ACM can result from mutations in several desmosomal genes. These genetic mutations impair the structure and function of cardiac desmosomes, which are membrane protein complexes engaged in cell-to-cell adhesion and the structural integrity of the ventricular myocardium. Lack of functioning cardiac desmosomes can lead to myocardial cell death and fibrosis, heart dysfunction, rhythm abnormalities, and sudden death. Standard of care may include antiarrhythmics, implantable cardioverter-defibrillators, and ablation procedures; however, none of these therapies address the underlying cause of myocardial dysfunction and ACM.

We estimate that ACM has a prevalence of approximately 130,000 patients in the United States and estimate that over half of all ACM patients have a genetic form of the disease with five desmosomal genes accounting for nearly all of the identified genetic causes of ACM. We have initially targeted the PKP2 gene because mutations in this gene are the most commonly known genetic cause of ACM. We believe that mutations in the PKP2 gene are associated with approximately 75% of all genetic cases of ACM, resulting in approximately 60,000 patients affected by the PKP2 mutation in the United States. Most familial cases of the disease have an autosomal dominant pattern of inheritance, meaning one copy of an altered gene in each cell is sufficient to cause the disorder. Since having only one functioning copy of the PKP2 gene is insufficient to produce the wild-type phenotype, this results in a phenomenon in genetics known as haploinsufficiency.

Symptoms of the disease can include palpitations, dizziness, heart failure and sudden death. Abnormal function of the right ventricle, fatty or fibrotic infiltrates in the myocardium, abnormal electrocardiogram, or ECG, arrhythmias, or a family history of ACM can all lead physicians to diagnose the disease. No effective treatments for PKP2-ACM exist.

Our approach: LX2020

We are developing LX2020 as an AAVrh10-based gene therapy candidate for the treatment of PKP2-ACM. LX2020 is designed to intravenously deliver a functional PKP2 gene to cardiac muscle to increase desmosomal PKP2 protein levels and restore myocardial cell function. We believe that by delivering a functional PKP2 gene, LX2020 has the potential to address the underlying cause of PKP2-ACM for many patients and have a significant effect on lifespan by reassembling the cardiac desmosomes, preventing cardiac arrhythmias and preventing or treating cardiac dysfunction.

LX2020 clinical development and trial design

LX2020 is currently being evaluated in HEROIC-PKP2, a first-in-human, 52-week, open-label, dose-ascending multicenter trial to determine the safety and tolerability of LX2020 in patients with PKP2-ACM. Preliminary efficacy measures include myocardial protein expression, biomarkers measuring cardiac structure and function, and arrhythmia burden. Key inclusion criteria include: patients aged 18-65 years with a confirmed diagnosis of ACM with either 2010 Task Force Criteria or 2020 International Criteria for ACM; documented PKP2 mutation; existing implantable cardioverter defibrillator (ICD) that is MRI compatible; and a minimum threshold of PVCs over a 24-hour period. LX2020 is administered as a one-time intravenous infusion to patients in at least two ascending-dose cohorts of three patients each, with the potential for cohort expansion. Prednisone and rapamycin are utilized for immune suppression. We have completed enrollment and dosing in this trial, with ten participants dosed: three in the low dose cohort 1 (2×1013 vg/kg), three in the high dose cohort 2 (6×1013 vg/kg), and four in the dose-expansion high dose cohort 3 (6×1013 vg/kg). There is a long-term follow-up for patients who receive LX2020 to monitor ongoing safety for a total of five years, per FDA requirement.

Cardiac biopsy results from HEROIC-PKP2 trial

In January 2026, we provided an interim clinical update, which included PKP2 protein expression from participants in HEROIC-PKP2 with post-treatment cardiac biopsies (n=7). The data demonstrated dose-dependent transduction and protein expression, with mean increase in PKP2 protein of 93% in low-dose (n=2) and 162% in high dose (n=5) by western blot, assessed at 3 months post dosing.

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Increases in PKP2 protein expression

Additionally, dose-dependent increases were observed in mean vector copy number and exogenous mRNA in all participants.

LX2020 transduction and transcription observed in all participants

Additionally, in two participants at the high dose, immunofluorescence demonstrates appropriate co-localization of PKP2 in desmosome. Following LX2020 administration, PKP2 protein colocalizes with Cx43, a gap junction protein, and Ncad, a desmosomal adhesion protein, within cardiac intercalated discs.

Immunofluorescence demonstrates appropriate co-localization of PKP2 in desmosome

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Cardiac biomarker data from HEROIC-PKP2

In January 2026, we provided an interim clinical data update, which included baseline characteristics and safety data from the ten participants dosed, including three participants in cohort 1 at the low dose and seven participants in cohorts 2 and 3 at the high dose. Clinical efficacy data were inclusive of those participants with at least 6 months of follow-up (n=8).

Arrhythmia burden stabilized or improved in majority of participants with dose-dependent response in NSVT and PVCs. NSVT reduced or stabilized in the majority of participants, with a 22% mean improvement in high-dose cohorts at latest visit (n=5). PVCs reduced or stabilized in the majority of participants, with a 14% mean improvement in high-dose cohorts at latest visit.

Reductions in arrhythmia burden over time

Additionally, four of five participants in high-dose cohorts report improvement relative to baseline on the Patient Global Impression of Change, or PGIC, scale, a patient-reported outcome measure. Participants stable across other clinical measures including QRS duration, T-wave inversion, RVEF and New York Heart Association, or NYHA, Class.

Safety profile of LX2020 from HEROIC-PKP2

Across all participants dosed, LX2020 has been generally well-tolerated to date with no clinically significant complement activation. Elevations in liver function tests (LFT) observed in seven participants at the high dose, treated successfully with re-introduction of low-dose prednisone in five participants and increased prednisone and sirolimus in two participants per the trial protocol. All elevations resolved without complication, hospitalization or other treatment. One Grade 3 serious adverse event of sustained ventricular tachycardia (VT) was observed three months after dosing in a single participant at the high dose and assessed as possibly treatment related. This event is consistent with the natural course of PKP2-ACM and its known clinical manifestations. The participant was successfully treated with anti-arrhythmic medication and discharged with no additional intervention required. No participants discontinued from the HEROIC-PKP2 Phase 1/2 study.

Additionally, we have initiated SNAPSHOT-PKP2, a natural history study designed to evaluate PKP2-ACM disease progression up to two years retrospectively and over twelve months prospectively. The study will enroll up to 20 patients in the United States.

We anticipate sharing additional safety and clinical efficacy data for LX2020 in the fourth quarter of 2026, once all participants in the high dose cohorts reach at least twelve months of follow up.

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LX2021 for the treatment of DSP cardiomyopathy

LX2021 is a gene therapy candidate we are developing to intravenously deliver the coding sequence for the functional Cx43 protein for a group of inherited cardiac muscle disorders associated with a high risk of sudden death, including ACM and certain forms of dilated cardiomyopathy, which are typically due to abnormalities or deficits in cardiac desmosomes. Cx43 is an integral protein component of gap junctions and functionally allows small molecules and ions to flow directly between cells to allow for electrical synchronization of muscle contraction. In patients with heart disease, including heart failure, Cx43 is often relocalized in the lateral walls of myocardial cells. As a result, it is significantly reduced at cardiac muscle cell junctions, especially in ACM populations. Restoring Cx43 protein to cardiac muscle cell-cell junctions can potentially treat multiple genetic causes of ACM because the cardiac loss of Cx43 is a molecular deficit generally observed in all ACM patient populations. DSP is a structural protein critical for force transmission in heart muscle. Mutations in DSP cause a distinct form of ACM and a certain form of dilated cardiomyopathy, known as DSP cardiomyopathy. Unlike many forms of ACM that predominantly affect the right side of the heart, DSP cardiomyopathy frequently affects the left side of the heart. The prevalence of DSP cardiomyopathy is unknown but may be as high as 4% of all inherited dilated cardiomyopathies and 4% of ACM, impacting up to 35,000 individuals in the U.S. Given the role of Cx43 in other forms of heart failure, we are also evaluating LX2021 for the treatment of additional indications beyond DSP cardiomyopathy.

We have conducted a preclinical study in a cardiac-specific DSP loss-of-function mouse model, or DSP-cKO mice, which is a genetic model of ACM. DSP-cKO mice develop molecular, histological and physiological features of ACM and ultimately die prematurely from heart failure. In this study, we observed that severely diseased mice treated with AAV-based gene therapy expressing Cx43 display fewer arrhythmias, have improved cardiac mechanical function, and experience an almost two-fold increase in lifespan when compared to untreated DSP-cKO adult mice. A single dose of an AAV-based gene therapy candidate representing Cx43 was administered intravenously to the cardiac-specific DSP-cKO mice, at four to six weeks of age. DSP-cKO mice are a genetic model of ACM harboring severe structural disease and loss of Cx43. RNA analysis of the treated mice revealed that cardiac-specific Cx43 gene delivery increased Cx43 RNA levels. Additionally, the Cx43-treated DSP-cKO mice showed a re-expression of mechanical junction proteins in their hearts compared to controls. Essential basement membrane proteins, including N-cadherin, as well as desmosomal proteins, PKP2 and junction plakoglobin, were also restored to cell-cell junctions in Cx43-treated DSP-cKO hearts compared to end-stage untreated DSP-cKO hearts, which had limited localization of junctional proteins at cell-cell junctions. These findings further validate the ability of Cx43 to resurrect the cardiac mechanical muscle junction complex in diseased hearts.

LX2022 for the treatment of HCM caused by TNNI3 mutations

LX2022 is a gene therapy candidate we are developing to intravenously deliver a functional TNNI3 gene to myocardial cells to treat a distinct form of HCM due to mutations in the TNNI3 gene. With an estimated prevalence of 1 in 500 people in the United States, HCM is one of the most common forms of genetic cardiomyopathy caused by mutations that affect the cardiac sarcomere in approximately 75% of cases. It is estimated that as many as 25,000 patients in the United States are affected by HCM caused by mutations in the gene TNNI3. The TNNI3 gene encodes troponin I, an essential protein in the thin filament of the sarcomere, which is involved in cardiac contraction and relaxation. Mutations in the gene often result in left ventricular hypertrophy and restrictive cardiomyopathy, leading to arrhythmias and heart failure.

Our preclinical data from an A157V TNNI3 murine model, a model which results in cardiac dysfunction, was generated to validate the delivery of an AAV-based therapy candidate expressing human TNNI3 regulated by a cardiac-specific promoter. At four weeks post injection, the level and specificity of TNNI3 gene expression were evaluated in the liver, skeletal muscle, and heart tissue. As TNNI3 was regulated by a cardiac-specific promoter, expression of TNNI3 was only detected in the heart tissue. Additionally, retro-orbital injection of AAV9-hTNNI3 expressing A157V mutation was performed on three- month-old mice euthanized four weeks later. The hearts were dissected and immunostained. Immunostaining revealed robust expression of human TNNI3 in the cardiomyocyte after treatment with AAV-based TNNI3. Moreover, high magnification imaging demonstrated the incorporation of TNNI3 within the cardiac sarcomere. Based on these preclinical findings, we believe that AAV-based therapy expressing TNNI3 can be administered to achieve transgene expression in heart tissue.

Outside of Core Focus Area: APOE4-associated Alzheimer’s disease programs

In addition to our cardiac gene therapy programs, we have a portfolio of approaches aimed at treating the genetics underlying Alzheimer’s disease. We believe precision therapies, particularly those focused on the underlying genetics of Alzheimer’s disease, may have a substantial impact on this treatment landscape. Importantly, we believe gene therapy allows for a unique approach to treating the genetics of Alzheimer’s disease by delivering a therapeutic which acts upstream of both the amyloid-b and tau-driven pathology of Alzheimer’s disease. This treatment strategy is designed to impact multiple pathways, as opposed to most other treatments in development which target a single mechanism of Alzheimer’s disease.

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In our lead Alzheimer’s disease program, LX1001, we are initially targeting homozygous APOE4-associated Alzheimer’s disease patients by administering AAVrh10 containing the APOE2 gene. Our approach to treating Alzheimer’s disease is predicated on the belief that expressing the protective APOE2 in the CNS of APOE4 homozygous patients will halt or slow the progression of Alzheimer’s disease. We believe these patients represent an ideal target for gene therapy because the APOE4 homozygous profile is the most common genetic driver of Alzheimer’s disease.

Our current gene therapy programs for the treatment of Alzheimer’s disease are:

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LX1001: a clinical-stage AAVrh10-based gene therapy candidate that is designed to express the protective APOE2 protein in the CNS of APOE4 homozygous patients.

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LX1021: an early-stage AAVrh10-based gene therapy candidate that is designed to express the Christchurch-modified APOE2 protein in the CNS of APOE4 homozygous patients. The Christchurch mutation has been observed to protect patients against Alzheimer’s disease even in the presence of significant amyloid pathology.

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LX1020: an early-stage AAVrh10-based gene therapy candidate that is designed to express the protective APOE2 protein in the CNS of APOE4 homozygous patients, while concurrently delivering miRNA to suppress the expression of the APOE4 protein.

LX1001 has been evaluated in an open-label, dose-ranging Phase 1/2 clinical trial in patients who are APOE4 homozygous patients with clinical diagnoses ranging from mild cognitive impairment to mild or moderate dementia due to Alzheimer’s disease. All participants had evidence of amyloid plaque by PET scan and/or CSF biomarkers consistent with Alzheimer’s disease at baseline. The trial evaluated four ascending dose cohorts (1.4×1010 vg/ml, 4.4×1010 vg/ml, 1.4×1011 vg/ml and 1.4×1014 total genomes), with the dose for each patient in the first three cohorts determined based on CSF volume measured by MRI and patients in the fourth cohort receiving a fixed dose. Fifteen patients were enrolled in the study across the four dose cohorts. The primary objective of the trial was to evaluate the safety of LX1001 administered to the CNS via injection between cervical vertebrae 1 and 2, or intracisternal injection, and to establish the maximum tolerated dose. The trial was also designed to evaluate the conversion of the CSF from the APOE4 homozygous profile to an APOE4/E2 profile. Additional secondary endpoints included CSF biomarkers, including Aß42, total tau, and phosphorylated tau, amyloid PET scan, structural MRI imaging and cognitive tests. Corticosteroids were utilized for immune suppression. Participants will continue to be evaluated for ongoing safety in a long-term follow-up study, per FDA requirement.

We have completed the Phase 1/2 trial of LX1001 and shared preliminary results across all four dose cohorts in a late-breaking oral presentation at the Clinical Trials on Alzheimer’s Disease Conference in October 2024. In January 2025 we announced that we are seeking partnering opportunities to continue development.

Competition

The biotechnology and pharmaceutical industries are characterized by rapidly changing technologies, significant competition and a strong emphasis on intellectual property. This is also true for the development and commercialization of treatments for cardiovascular and neurodegenerative diseases such as FA and PKP2-ACM and broadly across gene therapies. While we believe that our management and scientific team’s deep expertise in gene therapy provides us with competitive advantages, we face competition from several sources, including large and small biopharmaceutical companies, government agencies and academic and private research institutions. Not only must we compete with other companies that are focused on gene therapy technology, but any product candidates that we successfully develop and commercialize will compete with existing therapies, to the extent applicable, and new therapies that may become available in the future.

Drug development, particularly in the gene therapy field, is highly competitive and subject to rapid and significant technological advancements. A significant unmet medical need exists in each of the indications that we are targeting, and it is likely that additional drugs will become available in the future for the treatment of these diseases.

We are aware that our competitors are developing product candidates for the treatment of diseases that our product candidates will target. With respect to LX2006, we are aware of clinical stage gene therapy programs in development at Solid Biosciences Inc. and those being developed in collaborations between Voyager Therapeutics, Inc. and Neurocrine Biosciences, Inc. Among other treatment modalities for FA, we are aware that Larimar Therapeutics, Inc. is developing a clinical stage product candidate, CTI-1601, and that PTC Therapeutics, Inc. is evaluating next steps for vatiquinone following a Complete Response Letter on their new drug application to the FDA. Reata Pharmaceuticals, Inc.’s omaveloxolone (Skyclarys) was approved by the FDA in 2023, and Biogen Inc. acquired Reata Pharmaceuticals, Inc. for approximately $7.3 billion in the same year and is currently commercializing Skyclarys.

With respect to LX2020, both Rocket Pharmaceuticals Inc., or Rocket, and Tenaya Therapeutics Inc. are developing an AAV-based gene therapy candidate designed to deliver a functional PKP2 gene to patients with PKP2-ACM.

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Many of our existing or potential competitors have substantially greater financial, technical and human resources than we do and significantly greater experience in the discovery and development of product candidates, as well as in obtaining regulatory approvals of those product candidates in the United States and in foreign countries.

These competitors also compete with us in recruiting and retaining qualified scientific and management personnel and establishing clinical trial sites and patient registration for clinical trials, as well as in acquiring technologies complementary to, or necessary for, our programs. Mergers and acquisitions in the pharmaceutical and biotechnology industries may result in even more resources being concentrated among a smaller number of our competitors. Smaller or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies.

We will face competition from other drugs or from other non-drug products and treatments currently approved or that will be approved in the future in the cardiovascular and neurology field, including for the treatment of diseases and diseases in the therapeutic categories we intend to target. Therefore, our ability to compete successfully will depend largely on our ability to:

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develop, manufacture and commercialize drugs that are superior to other products in the market;

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demonstrate through our clinical trials that our product candidates are differentiated from existing and future therapies;

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attract qualified scientific, product development and commercial personnel;

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obtain patent or other proprietary protection for our medicines;

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obtain required regulatory approvals;

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obtain coverage and adequate reimbursement from, and negotiate competitive pricing with, third-party payors; and

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successfully collaborate with pharmaceutical companies in the discovery, development and commercialization of new medicines.

The availability of our competitors’ products could limit the demand, and the price we are able to charge, for any product candidate we develop. The inability to compete with existing or subsequently introduced drugs would have an adverse impact on our business, financial condition and prospects. In addition, the reimbursement structure of currently approved or future gene therapies by other companies could impact the anticipated reimbursement structure of our gene therapies, if approved, and our business, financial condition, results of operations and prospects.

Established pharmaceutical companies may invest heavily to accelerate discovery and development of novel compounds or to in-license novel compounds that could make our product candidates less competitive. In addition, any new product that competes with an approved product must demonstrate compelling advantages in efficacy, convenience, tolerability and safety in order to overcome price competition and to be commercially successful. Accordingly, our competitors may succeed in obtaining patent protection, discovering, developing, receiving regulatory and marketing approval for, or commercializing, drugs before we do, which would have an adverse impact on our business and results of operations.

Intellectual property

We actively seek to protect our proprietary technology, inventions, and other intellectual property that is commercially important to the development of our business by a variety of means, such as seeking, maintaining, and defending patent rights, whether developed internally or licensed from third parties. We also may rely on trade secrets and know-how relating to our proprietary technology platform, on continuing technological innovation and on in-licensing opportunities to develop, strengthen and maintain the strength of our position in the field of gene therapy that may be important for the development of our business. We also intend to seek patent protection or rely upon trade secret rights to protect other technologies that may be used to discover and validate targets, and that may be used to manufacture and develop novel gene therapy products. We are a party to license agreements that give us rights to use specific technologies in our gene therapy candidates and in manufacturing our products. Additional regulatory protection may also be afforded through data exclusivity, market exclusivity and patent term extensions where available.

As of December 31, 2025, we in-licensed four U.S. patents, 16 pending U.S. non-provisional patent applications, one pending PCT application, eight foreign patents and 106 pending foreign applications.

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In regard to our LX2006 product candidate, we in-license from Cornell University and Adverum Biotechnologies, Inc., or Adverum, two U.S. patents, five pending U.S. non-provisional patent applications, five foreign patents granted in India, Mexico, South Africa, and New Zealand and nine pending foreign applications pending in such jurisdictions as Australia, Brazil, Canada, Eurasia, Europe, Hong Kong, Israel and Mexico. Not accounting for any patent term adjustment and assuming that all annuity and/or maintenance fees are paid timely, these patents, if granted, will expire in 2033. These patents and pending patent applications disclose and/or contain composition-of-matter claims to an AAV vector encoding FXN, or a fragment thereof, and disclose and/or contain claims to methods of producing and methods of treatment using the AAV FXN vector. Cornell University co-owns these patents and patent applications with Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Université de Strasbourg, Université Paris-Saclay and Assistance Publique-Hôpitaux de Paris.

We have rights to additional patent applications that we co-own with Cornell University, and which also relate to our LX2006 cardiac FA program. We in-license Cornell University's interest in one pending U.S. non-provisional patent application and 14 pending foreign applications in such jurisdictions as Australia, Brazil, Canada, China, Eurasia, Europe, Hong Kong, Israel, India, Japan, Korea, Mexico, New Zealand, and South Africa. Not accounting for any patent term adjustment and assuming that all annuity and/or maintenance fees are paid timely, if granted, patents issuing from these applications will expire in 2043. These pending applications disclose and/or contain composition-of-matter claims to a pharmaceutical dosage form of viral vectors encoding FXN, and disclose and/or contain claims to methods of producing and methods of treatment using the pharmaceutical dosage form.

In regard to our LX2020 product candidate, we in-license from The Regents of the University of California one pending U.S. non-provisional patent application and 17 pending foreign applications in such jurisdictions as Australia, Brazil, Canada, China, Colombia, Eurasia, Europe, Hong Kong, Israel, India, Japan, Korea, Mexico, New Zealand, Singapore and South Africa. Not accounting for any patent term adjustment and assuming that all annuity and/or maintenance fees are paid timely, if granted, patents issuing from these applications will expire in 2042. These pending applications disclose and/or contain composition-of-matter claims to a vector encoding human PKP2, and disclose and/or contain claims to methods of producing and methods of treatment using the PKP2 vector.

In regard to our LX2021 product candidate, we in-license from The Regents of the University of California two U.S. patents, three pending U.S. non-provisional patent applications, two foreign patents granted in Australia and Europe, respectively, and nine pending foreign applications pending in Australia, Canada, China, Europe, Israel, and Japan. Not accounting for any patent term adjustment and assuming that all annuity and/or maintenance fees are paid timely, if granted, these patents and patent applications will expire in 2038. These pending patent applications disclose and/or contain composition-of-matter claims to a vector encoding a human Cx43 polypeptide, and disclose and/or contain claims to methods of producing and methods of treatment using the Cx43 vector.

In regard to our LX2022 product candidate, we in-license from The Regents of the University of California one pending U.S. non-provisional patent application. Not accounting for any patent term adjustment and assuming that all annuity and/or maintenance fees are paid timely, if granted, patent applications claiming the priority to this patent application, will expire in 2040. This pending U.S. non-provisional patent application discloses and/or contains composition-of-matter claims to a vector encoding a human TNNI3 gene, and discloses and/or contains claims to methods of producing and methods of treatment using the TNNI3 vector.

In regard to our LX1020 product candidate, we in-license from Cornell University one pending U.S. non-provisional application and 16 pending foreign applications pending in Australia, Brazil, Canada, China, Colombia, Europe, Hong Kong, Israel, Japan, Korea, Mexico, New Zealand, Singapore and South Africa. Not accounting for any patent term adjustment and assuming that all annuity and/or maintenance fees are paid timely, if granted, these patent applications will expire in 2040. We also in-license from Cornell an additional pending PCT application related to our LX1020 product candidate. Not accounting for any patent term adjustment and assuming that all annuity and/or maintenance fees are paid timely, if granted, patents claiming priority to the pending PCT application will expire in 2045. The pending patent applications disclose and/or contain composition-of-matter claims to a vector encoding human APOE2 protein and encoding one or more RNAi nucleic acid sequences for inhibition of APOE4 mRNA, and disclose and/or contain claims to methods of producing and methods of treatment using the APOE2+/APOE4- vector.

In regard to our LX1021 product candidate, we in-license from Cornell University two pending U.S. non-provisional application, one foreign patent granted in Australia, and 13 pending foreign applications pending in Brazil, Canada, China, Europe, Hong Kong, Israel, Japan, Korea, Mexico, New Zealand, Singapore and South Africa. Not accounting for any patent term adjustment and assuming that all annuity and/or maintenance fees are paid timely, if granted, these patent applications will expire in 2040. The patent and pending patent applications disclose and/or contain composition-of-matter claims to a vector encoding a mutated human apolipoprotein E protein, and disclose and/or contain claims to methods of producing and methods of treatment using the mutated human apolipoprotein E vector.

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We also in-license from Cornell additional patent applications, which relate to our LX1021 product candidate. We in-license from Cornell University one pending U.S. non-provisional application and 12 pending foreign applications pending in such jurisdictions as Australia, Brazil, Canada, China, Europe, Israel, Japan, Korea, Mexico, New Zealand, Singapore and South Africa. Not accounting for any patent term adjustment and assuming that all annuity and/or maintenance fees are paid timely, if granted, the pending patent applications will expire in 2044. The pending patent applications disclose and/or contain composition-of-matter claims to a vector encoding a mutated human apolipoprotein E protein, and disclose and/or contain claims to methods of producing and methods of treatment using the mutated human apolipoprotein E vector.

In regard to our LX1001 product candidate, we co-own pending patent applications with Cornell University. We in-license Cornell University's interest in one pending U.S. non-provisional patent application and 13 pending foreign applications pending in such jurisdictions as Australia, Brazil, Canada, China, Europe, Hong Kong, Israel, Japan, Korea, Mexico, New Zealand, Singapore and South Africa. Not accounting for any patent term adjustment and assuming that all annuity and/or maintenance fees are paid timely, if granted, the pending patent applications will expire in 2043. The pending patent applications disclose and/or contain composition-of-matter claims to a pharmaceutical dosage form of viral vectors encoding human APOE2, and discloses and/or contains claims to methods of producing and methods of treatment using the pharmaceutical dosage form.

License, research collaboration and sponsored research agreements

First license agreement with Cornell University

In May 2020, we entered into a license agreement with Cornell University, or the Cornell First License Agreement, pursuant to which we obtained a sublicensable, worldwide license under certain patents to make, use, and sell products that are covered by a valid claim of a licensed patent, are based on the transferred IND from Cornell University, use any licensed materials, or are produced using a licensed method, and to practice certain licensed technology, in all cases, for all human and non-human prophylactic and therapeutic uses. In July 2022, we entered into Amendment No. 1 to the Cornell First License Agreement that updated fees and royalties payable by us under the Cornell First License Agreement. In September 2022, we entered into Amendment No. 2 to the Cornell First License Agreement that clarified patent prosecution and maintenance obligations and added certain inventions and patents to the list of inventions and patent rights covered under the Cornell First License Agreement. The technology under the license includes portfolios for APOE, Alzheimer’s disease, and Anti-Tau, although our license is not restricted by such indications. The license is exclusive with respect to certain patents and non-exclusive with respect to other patents. Additionally, under the Cornell First License Agreement, Cornell University assigned to us an IND for the use of AAVrh10.hAPOE2 vector to treat APOE4 homozygous patients who are at risk of having or have Alzheimer’s disease. Cornell University reserved the rights to publish and disseminate information about inventions included in the licensed technology and licensed patents, and to use, and allow other nonprofit institutions to use, the patents and technology for educational and research purposes.

We are obligated to diligently proceed with the development, manufacture, and sale of licensed products, to raise certain amounts within specified time frames, to achieve certain development milestones within specified time frames, to meet agreed minimum-spend requirements, and to meet other diligence obligations. If we fail to perform these obligations, Cornell University could terminate the Cornell First License Agreement in full or in part in specified circumstances, subject to certain rights for us to extend these time frames.

Under the Cornell First License Agreement, we paid Cornell University an upfront payment of approximately $0.15 million and entered into a purchase agreement for approximately $0.6 million of convertible preferred securities. We are obligated to pay Cornell University an annual license maintenance fee ranging from the low four digits to the mid five digits, increasing annually until such time that we are commercially selling a licensed product. Under the Cornell First License Agreement, we are obligated to pay Cornell University up to $8.4 million for each portfolio upon the achievement of specific clinical and regulatory milestones. We are obligated to pay Cornell University a flat royalty in the mid-single-digits based on net sales of a licensed product in a country, which royalty rate increases by one percent if the licensed product is an orphan drug, subject to a reduction upon the expiration of valid claims in licensed patents and certain reductions for third-party licenses. In addition, in certain specific instances where sales are made by a sublicensee, the royalty rate increases by an amount in the low to mid-single digits. If the royalties are below certain agreed amounts, we are required to pay Cornell University minimum annual royalties ranging from low-six digits to low-seven digits. The royalty term continues for each licensed product on a country-by-country basis beginning on the first commercial sale of such licensed product and ending on the latest of (a) expiration or invalidation of the last valid claim in the licensed patent, (b) the expiration of regulatory exclusivity, and (c) the month of the first commercial launch of a generic equivalent in such country. We are also obligated to pay Cornell University a percentage of sublicensing fees in the low-double digits to mid-double digits.

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We may terminate the Cornell First License Agreement or any portfolio thereunder at any time upon ninety (90)-days’ advance written notice to Cornell University. Cornell University may terminate the Cornell First License Agreement if we commit a material breach and fail to cure such breach within a specified cure period after written notice or if we challenge the validity of a licensed patent. Upon expiration of the royalty term of a given licensed product in a country, the license becomes non-exclusive and royalty-free. Upon termination of the Cornell First License Agreement, all licenses and rights granted by either party will terminate, although we will have a period of time to sell off any remaining licensed product.

Second license agreement with Cornell University

In May 2020, we entered into a second license agreement with Cornell University, or the Cornell Second License Agreement, pursuant to which we obtained a sublicensable, worldwide license under certain patents to make, use, and sell products that are covered by a valid claim of a licensed patent, are based on the transferred IND from Cornell University, use any licensed materials, or are produced using a licensed method, and to practice certain licensed technology, in all cases, for all human and non-human prophylactic and therapeutic uses. In January 2022, we entered into Amendment No. 1 to the Cornell Second License Agreement, whereby we paid Cornell a material transfer fee and a license fee totaling $30,000, and Cornell added certain materials to the list of original materials subject to the Cornell Second License Agreement. In July 2022, we entered into Amendment No. 2 to the Cornell Second License Agreement that updated fees and royalties payable by us under the Cornell Second License Agreement. The technology under the license includes a portfolio for FA, although our license is not restricted by such indications. The license is exclusive with respect to certain patents and non-exclusive with respect to other patents. Cornell University reserved the rights to publish and disseminate information about inventions included in the licensed technology and licensed patents, and to use, and allow other nonprofit institutions to use, the patents and technology for educational and research purposes.

We are obligated to diligently proceed with the development, manufacture, and sale of licensed products, to raise certain amounts within specified time frames, to achieve certain development milestones within specified time frames, to meet agreed minimum-spend requirements, and to meet other diligence obligations. If we fail to perform these obligations, Cornell University could terminate the Cornell Second License Agreement in full or in part in specified circumstances, subject to certain rights for us to extend these time frames.

Under the Cornell Second License Agreement, we paid Cornell University an upfront payment of approximately $0.15 million and entered into a purchase agreement for approximately $0.6 million of convertible preferred securities. We are obligated to pay Cornell University an annual license maintenance fee ranging from the low four digits to the mid five digits, increasing annually until such time that we are commercially selling a licensed product. Under the Cornell Second License Agreement, we are obligated to pay Cornell University up to $4.3 million for two portfolios and up to $0.6 million for a third portfolio upon the achievement of specific clinical and regulatory milestones. Upon submitting our IND application for LX2006 to the FDA in the first quarter of 2022, we achieved the first clinical milestone under the Cornell Second License Agreement, and we paid $0.1 million to Cornell University in the second quarter of 2022 in connection with this milestone. We are obligated to pay Cornell University a flat royalty in the mid-single-digits based on net sales of a licensed product in a country, which royalty rate increases by one percent if the licensed product is an orphan drug, subject to a reduction upon the expiration of valid claims in licensed patents and certain reductions for third-party licenses. In addition, in certain specific instances where sales are made by a sublicensee, the royalty rate increases by an amount in the low to mid-single digits. If the royalties are below certain agreed amounts, we are required to pay Cornell University minimum annual royalties ranging from low six digits to low seven digits. The royalty term continues for each licensed product on a country-by-country basis beginning on the first commercial sale of such licensed product and ending on the latest of (a) expiration or invalidation of the last valid claim in the licensed patent, (b) the expiration of regulatory exclusivity, and (c) the month of the first commercial launch of a generic equivalent in such country. We are also obligated to pay Cornell University a percentage of sublicensing fees ranging in the low double digits.

We may terminate the Cornell Second License Agreement or any portfolio thereunder at any time upon ninety (90)-days’ advance written notice to Cornell University. Cornell University may terminate the Cornell Second License Agreement if we commit a material breach and fail to cure such breach within a specified cure period after written notice or if we challenge the validity of a licensed patent. Upon expiration of the royalty term of a given licensed product in a country, the license becomes non-exclusive and royalty-free. Upon termination of the Cornell Second License Agreement, all licenses and rights granted by either party will terminate, although we will have a period of time to sell off any remaining licensed product.

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Third license agreement with Cornell University

In April 2024, we entered into a third license agreement with Cornell University, or the Cornell Third License Agreement, pursuant to which we obtained certain rights for FA cardiomyopathy, including an exclusive license to practice under certain patent rights generated in animal studies conducted by Cornell University on our behalf and a non-exclusive license to know-how concerning a gene therapy for FA cardiomyopathy and current and future data generated in an ongoing Cornell University investigator-initiated Phase 1A trial of a gene therapy candidate AAVrh10.hFXN, known as LX2006 at Lexeo, to treat FA cardiomyopathy. Both licenses are worldwide and cover products with human and non-human prophylactic and therapeutic uses. Cornell University has also granted us a right of reference to its IND application for a gene therapy for FA cardiomyopathy.

We are obligated to diligently proceed with the development, manufacture, and sale of licensed products, to raise certain amounts within specified time frames, to achieve certain development milestones within specified time frames, to meet agreed minimum-spend requirements, and to meet other diligence obligations. If we fail to perform these obligations, Cornell University could terminate the Cornell Third License Agreement in full or in part in specified circumstances, subject to certain rights for us to extend these time frames.

Under the Cornell Third License Agreement, we paid a license issue fee and an initial data transfer fee to Cornell University totaling $0.6 million. Additionally, we will be paying an annual data transfer fee of $50,000 until data is no longer being gathered. We have agreed to pay annual license maintenance fees ranging from $2,500 to $25,000 until such time we commercialize a licensed product. In addition, we will pay Cornell University up to an aggregate of $2.1 million in regulatory milestones and up to an aggregate of $100 million in commercial milestones, plus low single digit royalties on net sales.

In March 2025, we entered into a Research Collaboration Agreement with Cornell University on behalf of Weill Cornell Medicine, or the 2025 Cornell Collaboration Agreement, in connection with the Cornell Third License Agreement entered into in April 2024. Under the 2025 Cornell Collaboration Agreement, we committed to fund scientific research at Weill Cornell Medicine related to intellectual property and know-how licensed to us pursuant to the Cornell Third License Agreement. Cornell University reserved the rights to publish and disseminate information about the results generated from Cornell University's investigator's conduct of the research.

Under the Cornell Third License Agreement, we committed to provide funding for research projects at Weill Cornell Medicine of $500,000 per year over a two-year period. The total budget for the research under the 2025 Cornell Collaboration Agreement is approximately $1.1 million, which will be credited against our research funding commitment under the Cornell Third License Agreement.

With respect to each Weill Cornell Medicine invention and joint invention and related joint results that is either an improvement to, or is dominated by, the patent rights under the Cornell Third License Agreement or is specifically designed for a licensed product under the Cornell Third License Agreement, or an Improvement, and for which we have made an election to obtain such inventions, the Cornell Third License Agreement will be amended to include license grants to such Improvements following payment of the relevant amendment fee in the low five digits. With respect to each Weill Cornell Medicine invention and joint invention and related joint results that are not Improvements, we have the first option to negotiate for a royalty-bearing, worldwide license under such intellectual property to develop, make, have made, use, offer for sale, sell, have sold and import products on commercially reasonable terms.

The 2025 Cornell Collaboration Agreement has a two-year term and may be terminated earlier by either party upon a material breach that remains uncured for 60 days following written notice.

License agreement with Adverum

In January 2021, we entered into a license agreement with Adverum, which we amended in February 2022 pursuant to the First Amendment to the Adverum Agreement, such agreement as amended, the Amended Adverum Agreement. Pursuant to the Amended Adverum Agreement, we obtained an exclusive, sublicensable, worldwide license under certain patents, know-how, and other intellectual property relating to viral vector technology for gene therapy applications for the treatment of FA cardiomyopathy.

We are responsible for the development, manufacture, and commercialization of gene therapy products that consist of a specific nucleic acid sequence that is delivered by a specific gene therapy, or the Products. We are obligated to use commercially reasonable efforts to develop, obtain regulatory approval for, and commercialize the Products.

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Under the Amended Adverum Agreement, we paid Adverum a $7.5 million upfront payment. We are obligated to pay Adverum up to $17.5 million upon the achievement of specified development and regulatory milestones, including a $3.5 million development milestone that was achieved in the first quarter of 2023, and up to $49 million in commercialization and sales milestones for the Products. We are obligated to pay Adverum tiered royalties ranging from high single-digits to sub teens based on annual aggregate worldwide net sales of Products, subject to reductions upon the expiration of valid claims in licensed patents and third-party licenses. The royalty term continues for each Product on a country-by-country basis beginning on the first commercial sale of such Product and ending on the latest of (a) expiration of the last valid claim in the licensed patent that covers the manufacture, use, or sale of the Product in such country, (b) the expiration of all regulatory and data exclusivity in such country, and (c) ten years after the first commercial sale of such Product in such country.

The Amended Adverum Agreement will expire, unless earlier terminated, on the expiration of the last royalty term for a Product in a particular country. We have the right to terminate the Amended Adverum Agreement at any time upon one-hundred twenty days’ advance written notice to Adverum. In addition, subject to certain conditions, either we or Adverum may terminate the Amended Adverum Agreement upon the insolvency of the other or if the other party commits a material breach of the agreement and fails to cure such breach within a specified cure period after written notice is provided. Additionally, Adverum may terminate the Amended Adverum Agreement if we challenge the validity of any licensed patents. Upon expiration of the Amended Adverum Agreement, the license becomes royalty-free, irrevocable and perpetual. Upon termination of the Amended Adverum Agreement, all licenses, sublicenses, and rights granted by either party will terminate.

On December 9, 2025, Eli Lilly and Company, or Lilly, announced the acquisition of Adverum pursuant to a tender offer by Lilly's wholly owned subsidiary to purchase all outstanding shares of Adverum common stock. Accordingly, Lilly assumed all of Adverum's obligations and responsibilities under the Amended Adverum Agreement after the acquisition.

First license agreement with The Regents of University of California, San Diego

Stelios Therapeutics, Inc., or Stelios, which we acquired in August 2021, is successor-in-interest to ARVC Therapeutics, Inc., or ARVC Therapeutics, under a worldwide license agreement entered into by ARVC Therapeutics and The Regents of the University of California, on April 23, 2020, or the UCSD First License Agreement, pursuant to which they obtained a license to certain intellectual property related to gene therapies for ARVC. The UCSD First License Agreement relates to our development efforts for our LX2021 program. Pursuant to the UCSD First License Agreement, we obtained an exclusive, sublicensable, worldwide license under certain patents to make, use, sell, offer for sale and import services, methods, composition and products that incorporate or are developed using any licensed invention or licensed methods, or is covered by a valid claim of a licensed patent, or a Product, in all cases for all diagnostic and therapeutic uses. The Regents of University of California, San Diego, or UCSD, reserved the right to practice the relevant invention and licensed patents for educational and research purposes, to publish and disseminate information about the relevant invention and licensed patents, and to allow other nonprofit institutions to use, publish, or disseminate information about the relevant inventions and licensed patents for educational and research purposes.

Under the UCSD First License Agreement, we are obligated to achieve certain development milestones within specified time frames, to use commercially reasonable efforts to diligently develop, manufacture, and sell Products, and to meet agreed minimum-spend requirements. If we fail to perform any of these obligations, UCSD could either terminate the UCSD First License Agreement or convert the exclusive license to a nonexclusive license, subject to certain rights for us to extend these time frames.

The UCSD First License Agreement required Stelios to pay one-time up-front non-refundable cash fees of $20,000. We are obligated to pay annual license maintenance fees in the mid-four digits to low-five digits, increasing until such time that we are commercially selling a Product. We are also obligated to pay up to $4.75 million upon the achievement of specific development and commercialization milestones for the first Product and low- to mid-single digit royalties based on aggregate net sales, subject to certain reductions for third-party licenses. The royalty term continues until the expiration of the UCSD First License Agreement. Under the UCSD First License Agreement, if the royalties are below certain agreed amounts, we are required to pay UCSD minimum annual royalties ranging from low- to mid-five digits. We are also obligated to pay UCSD a percentage of sublicensing fees ranging in the low double digits. In the event that we assign the UCSD First License Agreement, we will be obligated to pay an assignment fee that will be determined based on certain aspects of the assignment.

The UCSD First License Agreement will expire, unless earlier terminated, on the expiration of the last claim of any licensed patent or patent applications in a particular country. We have the right to terminate the UCSD First License Agreement at any time upon sixty (60)-days’ written notice to UCSD. UCSD may terminate the UCSD First License Agreement if we commit a material breach, if we fail to meet certain specified milestones within the prescribed time periods, if we are delinquent on any report or payment or provide an intentionally misleading report, if we fail to diligently develop and commercialize the licensed products, or if we challenge the validity of a licensed patent, in each case only if we fail to cure such problem within a specified cure period after written notice. Upon termination of the UCSD First License Agreement, all licenses and rights granted by UCSD to us will terminate.

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Second license agreement with The Regents of University of California, San Diego

Stelios, which we acquired in August 2021, entered into a worldwide license agreement in August 2020 with The Regents of the University of California, or the UCSD Second License Agreement, pursuant to which they obtained a license to certain intellectual property and materials related to gene therapies for HCM. The UCSD Second License Agreement relates to our development efforts for our LX2022 programs. Pursuant to the UCSD Second License Agreement, we obtained an exclusive, sublicensable, worldwide license under certain patents to make, use, sell, offer for sale and import services, methods, composition and products that incorporate or are developed using any licensed invention or licensed methods or is covered by a valid claim of a licensed patent, or a Product, and a non-exclusive license to use nonpublic technical information, or Technology, in all cases for all diagnostic and therapeutic uses. UCSD reserved the rights to practice the relevant invention, Technology and licensed patents for educational and research purposes, to publish and disseminate information about the relevant invention, Technology and licensed patents, and to allow other nonprofit institutions to use, publish, or disseminate information about the relevant invention, Technology and licensed patents for educational and research purposes.

Under the UCSD Second License Agreement, we are obligated to achieve certain development milestones within specified time frames and to use commercially reasonable efforts to diligently develop, manufacture, and sell Products. If we fail to perform any of these obligations, UCSD could either terminate the UCSD Second License Agreement or convert the exclusive license to a nonexclusive license subject to certain rights for us to extend these time frames.

The UCSD Second License Agreement required Stelios to pay one-time up-front non-refundable cash fees of $20,000. We are obligated to pay annual license maintenance fees in the mid-four digits to low-five digits, increasing until such time that we are commercially selling a Product. We are also obligated to pay up to $2.4 million upon the achievement of certain development and commercialization milestones for the first Product and low-single digit royalties based on aggregate net sales, subject to certain reductions for third-party licenses. The royalty term continues until the expiration of the UCSD Second License Agreement. We are also obligated to pay UCSD a percentage of sublicensing fees ranging in the low double digits.

On November 14, 2025, the Company entered into an amended and restated license agreement with UCSD, which amended, restated, and superseded the UCSD Second License Agreement in its entirety (the "Amended and Restated UCSD Second License Agreement"). The Amended and Restated UCSD Second License Agreement maintained the Company's prior exclusive worldwide license to materials and intellectual property related to a gene therapy for hypertrophic cardiomyopathy, replaced Stelios with the Company as licensee, and exclusively in-licensed additional materials and intellectual property related to the LX2022 program. The economic terms in the Amended and Restated UCSD Second License Agreement are substantially similar to the terms of the UCSD Second License Agreement.

The Amended and Restated UCSD Second License Agreement will expire, unless earlier terminated, on the expiration of the last claim of any licensed patent or patent applications in a particular country. We have the right to terminate the Amended and Restated UCSD Second License Agreement at any time upon sixty (60)-days’ written notice to UCSD. UCSD may terminate the Amended and Restated UCSD Second License Agreement if we commit a breach, if we fail to meet certain specified milestones within the prescribed time periods, if we are delinquent on any report or payment, if we are not diligently developing or commercializing Products in accordance with our diligence obligations, if we provide any intentionally false report, or if we challenge the validity of a licensed patent, in each case only if we fail to cure such problem within a specified cure period after written notice. In the event that we assign the Amended and Restated UCSD Second License Agreement, we will be obligated to pay an assignment fee that will be determined based on the acquisition price. Upon termination of the Amended and Restated UCSD Second License Agreement, all licenses and rights granted by UCSD to us will terminate.

Third license agreement with The Regents of University of California, San Diego

In October 2021, we entered into a worldwide license agreement with UCSD, or the UCSD Third License Agreement, and collectively with the UCSD First License Agreement and the UCSD Second License Agreement, The UCSD License Agreements, pursuant to which we obtained a license to materials and intellectual property related to a gene therapy for ARVC. The UCSD Third License Agreement relates to our development efforts for our LX2020 program. Pursuant to the UCSD Third License Agreement, we obtained an exclusive, sublicensable, worldwide license under certain patents to make, use, and sell, offer for sale and import services, methods, composition and products that incorporate or are developed using any licensed invention or licensed methods, or is covered by a valid claim of a licensed patent, or a Product, and an exclusive license to use nonpublic technical information, or Technology, in all cases for all diagnostic and therapeutic uses. UCSD reserved the rights to practice the relevant invention, Technology and licensed patents for educational and research purposes, to publish and disseminate information about the relevant invention, Technology and licensed patents, and to allow other nonprofit institutions to use, publish, or disseminate information about the relevant invention, Technology and licensed patents for educational and research purposes.

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Under the UCSD Third License Agreement, we are obligated to achieve certain development milestones within specified time frames, to use commercially reasonable efforts to diligently develop, manufacture, and sell licensed products, and to meet agreed minimum-spend requirements. If we fail to perform any of these obligations, UCSD could either terminate the UCSD Third License Agreement or convert the exclusive license to a nonexclusive license subject to certain rights for us to extend these time frames.

The UCSD Third License Agreement required us to pay a one-time up-front non-refundable cash fee of $20,000. We are obligated to pay annual license maintenance fees in the mid-four digits to low-five digits, increasing until such time that we are commercially selling a Product. We are also obligated to pay up to $4.0 million upon the achievement of specified development and commercialization milestones for the first Product and low- to mid-single digit royalties based on aggregate net sales, subject to certain reductions for third-party licenses. The royalty term continues until the expiration of the UCSD Third License Agreement. If the royalties are below certain agreed amounts, we are required to pay UCSD minimum annual royalties ranging from low- to mid-five digits. We are also obligated to pay UCSD a percentage of sublicensing fees ranging in the low double digits.

The UCSD Third License Agreement will expire, unless earlier terminated, on the expiration of the last claim of any licensed patent or patent applications in a particular country. We have the right to terminate the UCSD Third License Agreement at any time upon sixty (60)-days’ written notice to the UCSD. UCSD may terminate the UCSD Third License Agreement if we commit a material breach, if we fail to meet certain specified milestones within the prescribed time periods, if we are delinquent on any report or payment, if we are not diligently developing or commercializing Products in accordance with our diligence obligations, if we provide any intentionally false report, or if we challenge the validity of a licensed patent, in each case only if we fail to cure such problem within a specified cure period after written notice. In the event that we assign the UCSD Third License Agreement or we undergo a change of control, we will be obligated to pay a flat low-six digit fee or a fee that will be determined based on the acquisition price. Upon termination of the UCSD Third License Agreement, all licenses and rights granted by The Regents of UCSD to us will terminate.

Sponsored research agreements with The Regents of University of California, San Diego

In connection with the UCSD License Agreements, on December 3, 2021, we entered into a sponsored research agreement with UCSD for our LX2020 and LX2021 programs, or First UCSD SRA, which was subsequently amended on April 5, 2023 and August 31, 2023, and another sponsored research agreement with UCSD for our LX2022 program, or Second UCSD SRA, which was subsequently amended on April 19, 2023. We refer to these agreements, as amended, as the Amended UCSD SRAs. UCSD reserved the rights to publish and disseminate information about the results generated from UCSD’s investigator’s conduct of the research. The total costs to be invoiced to us under the terms of the Amended UCSD SRAs are approximately $5.6 million. Under the terms of the Amended UCSD SRAs, we have the first rights to obtain non-exclusive or exclusive, sublicensable, royalty-bearing, perpetual and transferable worldwide licenses to any inventions generated by UCSD or UCSD’s interest in any inventions generated jointly by The Regents of UCSD and us, and we retain the rights to any inventions generated solely by us.

On April 13, 2024, we entered into a third sponsored research agreement with UCSD, or the Third UCSD SRA, for our LX2022 program in connection with the UCSD Second License Agreement. Under the terms of the Third UCSD SRA, we have the first rights to obtain non-exclusive or exclusive, sublicensable, royalty-bearing, perpetual and transferable worldwide licenses in any resulting inventions owned by UCSD or resulting inventions jointly owned between us and UCSD, and we retain the rights to any resulting inventions owned by us. The Third UCSD SRA has a two-year term and may be terminated early by us at any time upon the giving of thirty (30)-days’ written notice to UCSD. The costs to be invoiced to us over the term of the Third UCSD SRA are $0.7 million, and we may incur additional costs of $0.6 million under the Third UCSD SRA if certain study objectives are met.

On April 13, 2024, we entered into another amendment to the Second UCSD SRA for our LX2022 program that extended the term of the Second UCSD SRA to December 2024.

On April 19, 2024 and September 27, 2024, we entered into amendments, respectively, to the First UCSD SRA for our LX2021 program in connection with the UCSD First License Agreement. We refer to the First UCSD SRA, as amended, as the Amended First UCSD SRA. The Amended First UCSD SRA extends the term of the First UCSD SRA to December 2026 and provides for additional research and development studies and expenses. The total costs to be invoiced to us under the Amended First UCSD SRA are $0.7 million.

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Government regulation

Government authorities in the United States at federal, state and local levels, as well as in foreign countries, extensively regulate, among other things, the research, development, testing, manufacture, quality control, import, export, safety, effectiveness, labeling, packaging, storage, distribution, recordkeeping, approval, advertising, promotion, marketing, post-approval monitoring and post-approval reporting of biologics, including gene therapies, such as those we are developing. Generally, before a new biologic can be marketed, considerable data demonstrating its quality, safety and efficacy must be obtained, organized into a format specific for each regulatory authority, submitted for review and approved, authorized, or cleared by the applicable regulatory authority. We, along with third-party contractors, will be required to navigate the various preclinical, clinical and commercial approval requirements of the governing regulatory agencies of the countries in which we wish to conduct studies or seek approval or licensure of our product candidates.

U.S. biologics regulation

In the United States, biological products are subject to regulation under the U.S. Federal Food, Drug, and Cosmetic Act, or FDCA, and the Public Health Service Act, or PHSA, and their implementing regulations and other federal, state, local and foreign statutes and regulations. Failure to comply with the applicable United States requirements at any time during the product development process, approval process or following approval may subject an applicant to administrative actions or judicial sanctions. These actions and sanctions could include, among other actions, the FDA’s refusal to approve pending applications, withdrawal of an approval, license revocation, a clinical hold, untitled or warning letters, voluntary or mandatory product recalls or market withdrawals, product seizures, total or partial suspension of production or distribution, injunctions, fines, refusals of government contracts, restitution, disgorgement and civil or criminal fines or penalties.

Our product candidates must be approved by the FDA through the BLA the process which is required by the FDA before biological product candidates may be marketed in the United States and generally involves the following:

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completion of extensive preclinical laboratory tests and animal studies performed in accordance with applicable regulations, including the FDA’s good laboratory practices, or GLPs, regulations;

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submission to the FDA of an IND application, which must become effective before human clinical trials may begin;

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approval by an Institutional Review Board, or IRB, or ethics committee at each clinical site before the trial is commenced;

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performance of adequate and well-controlled human clinical trials in accordance with applicable IND regulations, the FDA’s current Good Clinical Practices, or cGCPs, and other clinical trial-related regulations to establish the safety, purity and potency of the proposed biological product candidate for its intended purpose;

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preparation of and submission to the FDA of a BLA that contains sufficient data to demonstrate substantial evidence of effectiveness;

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a determination by the FDA within 60 days of its receipt of a BLA to file the application for review;

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payment of user fees for FDA review of the BLA;

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satisfactory completion of an FDA pre-license inspection of the manufacturing facility or facilities at which the proposed product will be produced to assess compliance with current good manufacturing practices, or cGMPs, and to assure that the facilities, methods and controls are adequate to ensure and preserve the biological product’s identity, strength, quality and purity, and of selected clinical investigation sites to assess compliance with the cGCPs;

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satisfactory completion of an FDA Advisory Committee review, if applicable; and

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FDA review and approval, or licensure, of a BLA to permit commercial marketing of the product for particular indications for use in the United States.

Preclinical and clinical development

Prior to beginning the first clinical trial with a product candidate, the product candidate must undergo rigorous preclinical testing. Preclinical studies include laboratory evaluation of product chemistry and formulation, as well as in vitro and animal studies to assess safety and in some cases to establish a rationale for therapeutic use. The conduct of preclinical studies is subject to federal and state regulations and requirements, including GLP regulations for safety/toxicology studies.

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An IND sponsor must submit the results of the preclinical tests, together with manufacturing information, analytical data, any available clinical data or literature and plans for clinical trials, among other things, to the FDA as part of an IND application to the FDA. An IND application is a request for authorization from the FDA to administer an IND product to humans. The central focus of an IND submission is on the general investigational plan and the protocol or protocols for preclinical studies and clinical trials. The IND application also includes results of animal and in vitro studies assessing the toxicology, pharmacokinetics, pharmacology and pharmacodynamic characteristics of the product, chemistry, manufacturing and controls information, and any available human data or literature to support the use of the investigational product. An IND application must become effective before human clinical trials may begin. The IND application automatically becomes effective 30 days after receipt by the FDA, unless the FDA, within the 30-day period, raises concerns or questions about the proposed clinical trial. In such a case, the IND application may be placed on clinical hold and the IND sponsor and the FDA must resolve any outstanding concerns or questions before the clinical trial can begin. Submission of an IND application therefore may or may not result in FDA authorization to begin a clinical trial. Additionally, the review of information in an IND submission may prompt FDA to, among other things, scrutinize existing INDs and could generate requests for information or clinical holds on other product candidates or programs.

Clinical trials involve the administration of the investigational product to human subjects under the supervision of qualified investigators, generally physicians not employed by or under the sponsor’s control, in accordance with cGCPs, which include the requirement that all research subjects provide their informed consent for their participation in any clinical study. Clinical trials are conducted under protocols detailing, among other things, the objectives of the trial, dosing procedures, subject selection and exclusion criteria and the parameters to be used in monitoring safety and the effectiveness criteria to be evaluated. A separate submission to the existing IND application must be made for each successive clinical protocol conducted during product development and for any subsequent protocol amendments. Furthermore, an independent IRB for each site proposing to conduct the clinical trial must review and approve the plan for any clinical trial and its informed consent form before the clinical trial begins at that site, and must monitor the study until completed to ensure that the risks to individuals participating in the clinical trial are minimized and are reasonable in relation to anticipated benefits.

A sponsor who wishes to conduct a clinical trial outside of the United States may, but need not, obtain FDA authorization to conduct the clinical trial under an IND application. If a foreign clinical trial is not conducted under an IND application, the sponsor may submit data from the clinical trial to the FDA in support of a BLA. The FDA will accept a well-designed and well-conducted foreign clinical trial not conducted under an IND application if the foreign data are applicable to the United States population and medical practice, the trial was performed by clinical investigators of recognized competence, the trial was conducted in accordance with cGCP requirements, and the data may be considered valid without the need for an on-site inspection by the FDA or the FDA is able to validate the data through an onsite inspection if deemed necessary.

For purposes of BLA approval of a product candidate, human clinical trials are typically conducted in three sequential phases that may overlap or be combined:

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Phase 1. For gene therapies in general, the investigational product is initially introduced into patients with the target disease or condition. These studies are designed to test the safety, dosage tolerance, absorption, metabolism and distribution of the investigational product in humans, the side effects associated with increasing doses, and, if possible, to gain early evidence on effectiveness.

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Phase 2. The investigational product is administered to a limited patient population to evaluate the preliminary efficacy, optimal dosages and dosing schedule and to identify possible adverse side effects and safety risks.

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Phase 3. The investigational product is administered to an expanded patient population to further evaluate dosage, to provide statistically significant evidence of clinical efficacy and to further test for safety, generally at multiple geographically dispersed clinical trial sites. These clinical trials are intended to establish the overall risk/benefit ratio of the investigational product and to provide an adequate basis for product approval.

When these phases overlap or are combined, the trials may be referred to as Phase 1/2 or Phase 2/3.

In some cases, the FDA may require, or companies may voluntarily pursue, additional clinical trials after a product is approved to gain more information about the product. These so-called Phase 4 studies may be made a condition to approval of the BLA. Concurrent with clinical trials, companies may complete additional animal studies and develop additional information about the characteristics of the product candidate, and must finalize a process for manufacturing the product in commercial quantities in accordance with cGMP requirements. The manufacturing process must be capable of consistently producing quality batches of the product candidate and, among other things, must develop methods for testing the identity, strength, potency, quality and purity of the final product. Additionally, appropriate packaging must be selected and tested and stability studies must be conducted to demonstrate that the product candidate does not undergo unacceptable deterioration over its shelf life.

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During all phases of clinical development, regulatory agencies require extensive monitoring and auditing of all clinical activities, clinical data and clinical study investigators. Written IND safety reports must be promptly submitted to the FDA and the investigators for serious, unexpected and suspected adverse events, any findings from other studies, tests in laboratory animals or in vitro testing that suggest a significant risk for human subjects, or any clinically important increase in the rate of a serious, and unexpected suspected adverse reaction over that listed in the protocol or investigator brochure. The sponsor must submit an IND safety report within 15 calendar days after the sponsor determines that the information qualifies for reporting. The sponsor also must notify the FDA of any unexpected fatal or life-threatening suspected adverse reaction within seven calendar days after the sponsor’s initial receipt of the information. The FDA or the sponsor may suspend a clinical study at any time on various grounds, including a finding that the research patients or patients are being exposed to an unacceptable health risk. Similarly, an IRB can suspend or terminate approval of a clinical study at its institution if the clinical study is not being conducted in accordance with the IRB’s requirements or if the biological product candidate has been associated with unexpected serious harm to patients. Some studies also include oversight by an independent group of qualified experts organized by the clinical study sponsor, known as a data safety monitoring board, which provides authorization for whether or not a study may move forward at designated checkpoints based on access to certain data from the study and may recommend halting the clinical trial if it determines that there is an unacceptable safety risk for subjects or other grounds, such as no demonstration of efficacy. There are also requirements governing the reporting of ongoing clinical trials and completed clinical trial results to public registries. Sponsors of clinical trials of FDA-regulated products, including biologics, are required to register and disclose certain clinical trial information, which is publicly available at www.clinicaltrials.gov.

BLA submission and review

Assuming successful completion of all required testing in accordance with all applicable regulatory requirements, the results of product development, preclinical studies and clinical trials are submitted to the FDA as part of a BLA requesting approval to market the product for one or more indications. FDA approval of a BLA must be obtained before a biologic may be marketed in the United States. The BLA must include all relevant data available from pertinent preclinical studies and clinical trials, including negative or ambiguous results as well as positive findings, together with detailed information relating to the product’s chemistry, manufacturing, controls and proposed labeling, among other things. The submission of a BLA requires payment of a substantial application user fee to the FDA, unless a waiver or exemption applies. No user fees are assessed on BLAs for products designated as orphan drugs, unless the product also includes a non-orphan indication. The FDA reviews all submitted BLAs before it accepts them for filing, and may request additional information rather than accepting the BLA for filing. The FDA has 60 days from the applicant’s submission of a BLA to either issue a refusal to file letter or accept the BLA for filing, indicating that it is sufficiently complete to permit substantive review.

Once a BLA has been accepted for filing, the FDA’s goal is to review standard applications within ten months after it accepts the application for filing, or, if the application qualifies for priority review, six months after the FDA accepts the application for filing. In both standard and priority reviews, the review process can be significantly extended by FDA requests for additional information or clarification. The FDA reviews a BLA to determine, among other things, whether a product is safe, pure and potent for its intended use, and whether the facility in which it is manufactured, processed, packed or held meets standards designed to ensure and preserve the product’s identity, safety, strength, quality, potency and purity. The FDA may convene an advisory committee, typically a panel that includes clinicians and other experts, to provide clinical insight on applications for novel products or products which present difficult questions of safety or efficacy. The advisory committee will provide a recommendation as to whether the application should be approved and under what conditions, if any. The FDA is not bound by the recommendations of an advisory committee, but it considers such recommendations when making decisions on approval. Before approving a BLA, the FDA will typically inspect the facility or facilities where the product is manufactured. The FDA will not approve an application unless it determines that the manufacturing processes and facilities are in compliance with cGMP requirements and adequate to assure consistent production of the product within required specifications. Additionally, before approving a BLA, the FDA will typically inspect one or more clinical sites to assure compliance with cGCPs. If the FDA determines that the application, manufacturing process or manufacturing facilities are not acceptable, it will outline the deficiencies in the submission and often will request additional testing or information. Notwithstanding the submission of any requested additional information, the FDA ultimately may decide that the application does not satisfy the regulatory criteria for approval.

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After the FDA evaluates a BLA and conducts inspections of manufacturing facilities where the investigational product and/or its drug substance will be manufactured, the FDA may issue an approval letter or a Complete Response Letter. An approval letter authorizes commercial marketing of the product with specific prescribing information for specific indications. A Complete Response Letter indicates that the review cycle of the application is complete, and the application will not be approved in its present form. A Complete Response Letter will usually describe all of the deficiencies that the FDA has identified in the BLA, except that where the FDA determines that the data supporting the application are inadequate to support approval, the FDA may issue the Complete Response Letter without first conducting required inspections, testing submitted product lots and/or reviewing proposed labeling. In issuing the Complete Response Letter, the FDA may recommend actions that the applicant might take to place the BLA in condition for approval, including requests for additional information or clarification, which may include the potential requirement for additional preclinical studies or clinical trials or additional manufacturing activities. If a Complete Response Letter is issued, the applicant may either resubmit the BLA, addressing all of the deficiencies identified in the letter, or withdraw the application or request an opportunity for a hearing. The FDA may delay or refuse approval of a BLA if applicable regulatory criteria are not satisfied, require additional testing or information and/or require post-marketing testing and surveillance to monitor the safety or efficacy of a product. Further, FDA’s “real time” release of newly issued Complete Response Letters associated with withdrawn or abandoned applications, if applicable to any of our product candidates, can materially impact our business and competitive advantage.

If regulatory approval of a product is granted, such approval will be granted for particular indications and may entail limitations on the indicated uses for which such product may be marketed. For example, the FDA may approve the BLA with a Risk Evaluation and Mitigation Strategy, or REMS, to ensure the benefits of the product outweigh its risks. A REMS is a safety strategy to manage a known or potential serious risk associated with a product and to enable patients to have continued access to such medicines by managing their safe use, and could include medication guides, physician communication plans, or elements to assure safe use, such as restricted distribution methods, patient registries and other risk minimization tools. The FDA also may condition approval on, among other things, changes to proposed labeling or the development of adequate controls and specifications. Once approved, the FDA may withdraw the product approval if compliance with pre- and post-marketing requirements is not maintained or if problems occur after the product reaches the marketplace. The FDA may require one or more Phase 4 post-market studies and surveillance to further assess and monitor the product’s safety and effectiveness after commercialization, and may limit further marketing of the product based on the results of these post-marketing studies.

Expedited development and review programs

The FDA offers a number of expedited development and reviews programs for qualifying product candidates. The Fast Track program is intended to expedite or facilitate the process for developing new products that meet certain criteria. Specifically, product candidates are eligible for Fast Track designation if they are intended to treat a serious or life-threatening disease or condition and demonstrate the potential to address unmet medical needs for the disease or condition. Fast Track designation applies to the combination of the product candidate and the specific indication for which it is being studied. The sponsor of a Fast Track designated product candidate has opportunities for frequent interactions with the FDA review team during product development and, once a BLA is submitted, the product candidate may be eligible for priority review. A Fast Track designated product candidate may also be eligible for rolling review, where the FDA may consider for review sections of the BLA on a rolling basis before the complete application is submitted, if the sponsor provides a schedule for the submission of the sections of the BLA, the FDA agrees to accept sections of the BLA and determines that the schedule is acceptable, and the sponsor pays any required user fees upon submission of the first section of the BLA. The sponsor can request the FDA to designate the product candidate for Fast Track status any time before receiving BLA approval, but ideally no later than the pre-BLA meeting.

A product candidate intended to treat a serious or life-threatening disease or condition may also be eligible for Breakthrough Therapy designation to expedite its development and review. A product candidate may receive Breakthrough Therapy designation if preliminary clinical evidence indicates that the product candidate, alone or in combination with one or more other drugs or biologics, may demonstrate substantial improvement over available therapies on one or more clinically significant endpoints, such as substantial treatment effects observed early in clinical development. The designation includes all of the Fast Track program features, as well as more intensive FDA interaction and guidance beginning as early as Phase 1 and an organizational commitment to expedite the development and review of the product candidate, including involvement of senior managers.

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As part of the 21st Century Cures Act, Congress amended the FDCA to facilitate an efficient development program for, and expedite review of regenerative medicine therapies, which include cell therapies, therapeutic tissue engineering products, human cell and tissue products, and combination products using any such therapies or products. Gene therapies, including genetically modified cells that lead to a durable modification of cells or tissues may meet the definition of a “regenerative medicine therapy.” A product candidate may be eligible for RMAT designation if it meets the following criteria: (1) it is a regenerative medicine therapy; (2) it is intended to treat, modify, reverse, or cure a serious or life-threatening disease or condition; and (3) preliminary clinical evidence indicates that it has the potential to address unmet medical needs for such a disease or condition. A sponsor may request that the FDA designate a product candidate as an RMAT concurrently with or at any time after the submission of an IND. A BLA for a product candidate that has received RMAT designation may be eligible for priority review or accelerated approval through (1) surrogate or intermediate endpoints reasonably likely to predict long-term clinical benefit or (2) reliance upon data obtained from a meaningful number of sites. Benefits of such designation also include early interactions with FDA to discuss any potential surrogate or intermediate endpoint to be used to support accelerated approval. A product candidate with RMAT designation that is granted accelerated approval and is subject to post-approval requirements may fulfill such requirements through the submission of clinical evidence, clinical studies, patient registries, or other sources of real world evidence, such as electronic health records; the collection of larger confirmatory data sets; or post-approval monitoring of all patients treated with such therapy prior to its approval.

Any marketing application for a biologic submitted to the FDA for approval, including a product with a Fast Track designation and/or Breakthrough Therapy designation, may be eligible for other types of FDA programs intended to expedite the FDA review and approval process, such as priority review. A product is eligible for priority review if it is designed to treat a serious or life threatening disease or condition and, if approved, would provide a significant improvement in safety and effectiveness compared to available therapies. For original BLAs, priority review designation means the FDA’s goal is to take action on the marketing application within six months of the 60-day filing date.

Additionally, a product candidate may be eligible for accelerated approval if it is designed to treat a serious or life-threatening disease or condition and demonstrates an effect on a surrogate endpoint that is reasonably likely to predict clinical benefit, or on a clinical endpoint that can be measured earlier than irreversible morbidity or mortality, or IMM, that is reasonably likely to predict an effect on IMM or other clinical benefit, taking into account the severity, rarity, or prevalence of the condition and the availability or lack of alternative treatments. As a condition of accelerated approval, the FDA will generally require the sponsor to perform adequate and well-controlled post-marketing clinical studies with due diligence to verify and describe the anticipated effect on IMM or other clinical benefit. The FDA may withdraw approval of a product or indication approved under accelerated approval if, for example, the confirmatory trial fails to verify the predicted clinical benefit of the product. In addition, for products being considered for accelerated approval, the FDA generally requires, unless otherwise informed by the agency, pre-approval of all advertising and promotional materials intended for dissemination or publication, which could adversely impact the timing of the commercial launch of the product. The Food and Drug Omnibus Reform Act also made several changes to the FDA’s authorities and its regulatory framework, including, among other changes, reforms to the accelerated approval pathway, such as requiring the FDA to specify conditions for post-approval study requirements and setting forth procedures for the FDA to withdraw a product on an expedited basis for non-compliance with post-approval requirements.

Fast Track designation, Breakthrough Therapy designation, RMAT designation, and priority review do not change the standards for approval but may expedite the development or approval process. Even if a product qualifies for one or more of these programs, the FDA may later decide that the product no longer meets the conditions for qualification or decide that the time period for FDA review or approval will not be shortened.

Orphan Drug designation

Under the Orphan Drug Act, the FDA may grant Orphan Drug designation to a product candidate intended to treat a rare disease or condition, which is generally a disease or condition that affects fewer than 200,000 individuals in the United States, or 200,000 or more individuals in the United States for which there is no reasonable expectation that the cost of developing and making available in the United States a drug or biologic for this type of disease or condition will be recovered from sales in the United States for that product candidate. Orphan Drug designation must be requested before submitting a BLA. After the FDA grants Orphan Drug designation, the identity of the therapeutic agent and its potential orphan use are disclosed publicly by the FDA. The Orphan Drug designation does not convey any advantage in, or shorten the duration of, the regulatory review or approval process.

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If a product that has Orphan Drug designation subsequently receives the first FDA approval for the disease or condition for which it has such designation, the product is entitled to orphan drug exclusive approval (or exclusivity), which means that the FDA may not approve any other applications, including a full BLA, to market the same product for the same indication for seven years, except in limited circumstances, such as a showing of clinical superiority to the product with orphan drug exclusivity by means of greater effectiveness, greater safety or providing a major contribution to patient care or if the holder of the orphan drug exclusivity cannot assure the availability of sufficient quantities of the orphan drug to meet the needs of patients with the disease or condition for which the product was designated. Orphan drug exclusivity does not prevent the FDA from approving a different drug or biologic for the same disease or condition, or the same drug or biologic for a different disease or condition. Among the other benefits of Orphan Drug designation are tax credits for certain research and a waiver of the BLA application fee.

A designated orphan drug may not receive orphan drug exclusivity if it is approved for a use that is broader than the indication for which it received Orphan Drug designation. In addition, exclusive marketing rights in the United States may be lost if the FDA later determines that the request for designation was materially defective or if the manufacturer is unable to assure sufficient quantities of the product to meet the needs of patients with the rare disease or condition. In view of the court decision in Catalyst Pharms., Inc. v. Becerra, 14 F.4th 1299 (11th Cir. 2021), in January 2023, the FDA published a notice in the Federal Register to clarify that while the agency complies with the court’s order in Catalyst, FDA intends to continue to apply its longstanding interpretation of the regulations to matters outside of the scope of the Catalyst order – that is, the agency will continue tying the scope of orphan-drug exclusivity to the uses or indications for which a drug is approved, which permits other sponsors to obtain approval of a drug for new uses or indications within the same orphan designated disease or condition that have not yet been approved. The Consolidated Appropriations Act of 2026, signed into law in February 2026, codified this longstanding FDA interpretation of the Orphan Drug Act.

In June 2024, the U.S. Supreme Court overruled the Chevron doctrine, which gives deference to regulatory agencies’ statutory interpretations in litigation against federal government agencies, such as the FDA, where the law is ambiguous. This landmark Supreme Court decision may invite various stakeholders to bring lawsuits against the FDA to challenge longstanding decisions and policies, which could lead to uncertainties in the industry. Further, changes in the leadership of the FDA and other federal agencies under the Trump administration may lead to new policies, changes in the regulations, or disruptions to the operations of federal agencies, any of which may impact our clinical development plans.

Rare Pediatric Disease designation and priority review vouchers

Under the FDCA, as amended, the FDA incentivizes the development of product candidates that meet the definition of a “rare pediatric disease,” defined to mean a serious or life-threatening disease in which the serious or life-threatening manifestations primarily affect individuals aged from birth to 18 years and the disease affects fewer than 200,000 individuals in the United States or affects 200,000 or more in the United States and for which there is no reasonable expectation that the cost of developing and making in the United States a drug for such disease or condition will be received from sales in the United States of such drug. The sponsor of a product candidate for a rare pediatric disease may be eligible for a voucher that can be used to obtain a priority review for a subsequent human drug or biologic application after the date of approval of the rare pediatric disease drug product. A sponsor may request Rare Pediatric Disease designation from the FDA prior to the submission of its BLA. A Rare Pediatric Disease designation does not guarantee that a sponsor will receive a priority review voucher, or PRV, upon approval of its BLA. Moreover, a sponsor who chooses not to submit a Rare Pediatric Disease designation request may nonetheless receive a PRV upon approval of their marketing application if they request such a voucher in their original marketing application and meet all of the eligibility criteria. If a PRV is received, it may be sold or transferred an unlimited number of times. The Consolidated Appropriations Act of 2026 extended the rare pediatric disease PRV program to September 30, 2029, which means the FDA may not award any PRVs under this program after September 30, 2029, unless Congress takes further action to extend the program.

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Pediatric information and pediatric exclusivity

Under the Pediatric Research Equity Act, or PREA, certain BLAs and certain supplements to a BLA must contain data to assess the safety and efficacy of the product for the claimed indications in all relevant pediatric subpopulations and to support dosing and administration for each pediatric subpopulation for which the product is safe and effective. The FDA may grant deferrals for the submission of pediatric data or full or partial waivers. The Food and Drug Administration Safety and Innovation Act, or FDASIA, amended the FDCA to require that a sponsor who is planning to submit a marketing application for a product that includes a new active ingredient, new indication, new dosage form, new dosing regimen or new route of administration submit an initial Pediatric Study Plan, or PSP, within 60 days of an end-of-Phase 2 meeting or, if there is no such meeting, as early as practicable before the initiation of the Phase 3 or Phase 2/3 study. The initial PSP must include an outline of the pediatric study or studies that the sponsor plans to conduct, including study objectives and design, age groups, relevant endpoints and statistical approach, or a justification for not including such detailed information, and any request for a deferral of pediatric assessments or a full or partial waiver of the requirement to provide data from pediatric studies along with supporting information. The FDA and the sponsor must reach an agreement on the PSP. A sponsor can submit amendments to an agreed-upon initial PSP at any time if changes to the pediatric plan need to be considered based on data collected from preclinical studies, early phase clinical trials and/or other clinical development programs. A biological product can also obtain pediatric market exclusivity in the United States. Pediatric exclusivity, if granted, adds six months to existing exclusivity periods. This six-month exclusivity, which runs from the end of other exclusivity protection, may be granted based on the voluntary completion of a pediatric study in accordance with an FDA-issued “Written Request” for such a study.

Post-approval requirements

Any products manufactured or distributed by us pursuant to FDA approvals are subject to pervasive and continuing regulation by the FDA, including, among other things, requirements relating to record-keeping, reporting of adverse experiences, periodic reporting, product sampling and distribution, and advertising and promotion of the product. As part of the manufacturing process, the manufacturer is required to perform certain tests on each lot of the product before it is released for distribution. After a BLA is approved for a biological product, the product also may be subject to official lot release. If the product is subject to official release by the FDA, the manufacturer submits samples of each lot of product to the FDA together with a release protocol showing a summary of the history of manufacture of the lot and the results of all of the manufacturer’s tests performed on the lot. The FDA also may perform certain confirmatory tests on lots of some products before releasing the lots for distribution by the manufacturer. In addition, the FDA conducts laboratory research related to the regulatory standards on the safety, purity, potency and effectiveness of biologics. After approval, most changes to the approved product, such as adding new indications or other labeling claims, are subject to prior FDA review and approval. There also are continuing user fee requirements, under which the FDA assesses an annual program fee for each product identified in an approved BLA. Biologic manufacturers and their subcontractors are required to register their establishments with the FDA and certain state agencies, and are subject to periodic unannounced inspections by the FDA and certain state agencies for compliance with cGMPs, which impose certain procedural and documentation requirements upon us and our third-party manufacturers. Changes to the manufacturing process are strictly regulated, and, depending on the significance of the change, may require prior FDA approval before being implemented. FDA regulations also require investigation and correction of any deviations from cGMPs and impose reporting requirements upon us and any third-party manufacturers that we may decide to use. Manufacturers and other parties involved in the drug supply chain for prescription drug products must also comply with product tracking and tracing requirements and for notifying the FDA of counterfeit, diverted, stolen and intentionally adulterated products or products that are otherwise unfit for distribution in the United States. Accordingly, manufacturers must continue to expend time, money and effort in the area of production and quality control to maintain compliance with cGMPs and other aspects of regulatory compliance.

The FDA may withdraw approval if compliance with regulatory requirements and standards is not maintained or if problems occur after the product reaches the market. Later discovery of previously unknown problems with a product, including adverse events of unanticipated severity or frequency, or with manufacturing processes, or failure to comply with regulatory requirements, may result in revisions to the approved labeling to add new safety information; imposition of post-market studies or clinical studies to assess new safety risks; or imposition of distribution restrictions or other restrictions under a REMS program. Other potential consequences include, among other things:

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restrictions on the marketing or manufacturing of a product, complete withdrawal of the product from the market or product recalls;

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fines, warning or untitled letters or holds on post-approval clinical studies;

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refusal of the FDA to approve pending applications or supplements to approved applications, or suspension or revocation of existing product approvals;

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product seizure or detention, or refusal of the FDA to permit the import or export of products;

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consent decrees, corporate integrity agreements, debarment or exclusion from federal healthcare programs;

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mandated modification of promotional materials and labeling and the issuance of corrective information;

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the issuance of safety alerts, Dear Healthcare Provider letters, press releases and other communications containing warnings or other safety information about the product; or

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injunctions or the imposition of civil or criminal penalties.

The FDA closely regulates the marketing, labeling, advertising and promotion of biologics. A company can make only those claims relating to safety and efficacy, purity and potency that are approved by the FDA and in accordance with the provisions of the approved label. However, companies may share truthful and not misleading information that is otherwise consistent with a product’s FDA-approved labeling. The FDA and other agencies actively enforce the laws and regulations prohibiting the promotion of off-label uses. Failure to comply with these requirements can result in, among other things, adverse publicity, warning letters, corrective advertising and potential civil and criminal penalties. Physicians may prescribe legally available products for uses that are not described in the product’s labeling and that differ from those tested by us and approved by the FDA. Such off-label uses are common across medical specialties. Physicians may believe that such off-label uses are the best treatment for many patients in varied circumstances. The FDA does not regulate the behavior of physicians in their choice of treatments. The FDA does, however, restrict manufacturer’s communications on the subject of off-label use of their products.

Biosimilars and reference product exclusivity

The Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act, or collectively, the ACA, includes a subtitle called the Biologics Price Competition and Innovation Act, or BPCIA, which created an abbreviated approval pathway for biologics that are biosimilar to or interchangeable with an FDA-approved reference biological product. To date, a number of biosimilars have been licensed under the BPCIA, and numerous biosimilars have been approved in Europe. The FDA has issued several guidance documents outlining an approach to review and approval of biosimilars.

Biosimilarity, which requires that there be no clinically meaningful differences between the biological product and the reference product in terms of safety, purity and potency, can be shown through analytical studies, animal studies and a clinical study or studies. Interchangeability requires that a product is biosimilar to the reference product and the product must demonstrate that it can be expected to produce the same clinical results as the reference product in any given patient and, for products that are administered multiple times to an individual, the biologic and the reference biologic may be alternated or switched after one has been previously administered without increasing safety risks or risks of diminished efficacy relative to exclusive use of the reference biologic. Complexities associated with the larger, and often more complex, structures of biologics, as well as the processes by which such products are manufactured, pose significant hurdles to the implementation of the abbreviated approval pathway that are still being worked out by the FDA.

Under the BPCIA, an application for a biosimilar product may not be submitted to the FDA until four years following the date that the reference product was first licensed by the FDA. In addition, the approval of a biosimilar product may not be made effective by the FDA until 12 years from the date on which the reference product was first licensed. During this 12-year period of exclusivity, another company may still market a competing version of the reference product if the FDA approves a full BLA for the competing product containing that applicant’s own preclinical data and data from adequate and well-controlled clinical trials to demonstrate the safety, purity and potency of its product. The BPCIA also created certain exclusivity periods for biosimilars approved as interchangeable products. At this juncture, it is unclear whether products deemed “interchangeable” by the FDA will, in fact, be readily substituted by pharmacies, which are governed by state pharmacy law.

The BPCIA is complex and continues to be interpreted and implemented by the FDA. In addition, government proposals have sought to reduce the 12-year reference product exclusivity period. Other aspects of the BPCIA, some of which may impact the BPCIA exclusivity provisions, have also been the subject of recent litigation. As a result, the ultimate impact and implementation of the BPCIA are subject to significant uncertainty.

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Regulation of companion diagnostics

If an in vitro diagnostic, which is regulated by the FDA as a medical device, is essential to the safe and effective use of a therapeutic and is not available on the market, then the FDA generally will require approval or clearance of that diagnostic, known as a companion diagnostic, at the same time that the FDA approves the therapeutic product. In August 2014, the FDA issued final guidance clarifying the requirements that will apply to approval of therapeutic products and in vitro companion diagnostics. According to the guidance, an unapproved or uncleared companion diagnostic device used to make treatment decisions in clinical trials of a drug generally will be considered an investigational medical device unless it is employed for an intended use for which the device is already approved or cleared. If used to make critical treatment decisions, such as patient selection, the diagnostic device generally will be considered a significant risk device under the FDA’s Investigational Device Exemption, or IDE, regulations. The sponsor of the diagnostic device will be required to comply with the IDE regulations for clinical studies involving the investigational diagnostic device. According to the guidance, if a diagnostic device and a drug are to be studied together to support their respective approvals, both products can be studied in the same clinical trial, if the trial meets both the requirements of the IDE regulations and the IND regulations. The guidance provides that depending on the details of the clinical trial protocol, the investigational product(s), and subjects involved, a sponsor may seek to submit an IDE alone (e.g., if the drug has already been approved by FDA and is used consistent with its approved labeling), or both an IND and an IDE.

Pursuing FDA approval/clearance of an in vitro companion diagnostic would require either a pre-market notification, also called 510(k) clearance, or a pre-market approval, or PMA, or a de novo classification for that diagnostic. The review of companion diagnostics involves coordination of review with the FDA’s Center for Devices and Radiological Health. Once cleared or approved, the companion diagnostic must adhere to post-marketing requirements including the requirements of FDA’s quality system regulation, medical device reporting, recalls and corrections along with product marketing requirements and limitations. Companion diagnostic manufacturers are subject to unannounced FDA inspections at any time during which the FDA will conduct an audit of the product(s) and the company’s facilities for compliance with its authorities.

510(k) clearance process

To obtain 510(k) clearance, a pre-market notification is submitted to the FDA demonstrating that the proposed device is substantially equivalent to a previously cleared 510(k) device or a device that was in commercial distribution before May 28, 1976 for which the FDA has not yet required the submission of a PMA application. The FDA’s 510(k) clearance process may take three to 12 months from the date the application is submitted and filed with the FDA, but may take longer if FDA requests additional information, among other reasons. In some cases, the FDA may require clinical data to support substantial equivalence. In reviewing a pre-market notification submission, the FDA may request additional information, which may significantly prolong the review process. Notwithstanding compliance with all these requirements, clearance is never assured. After a device receives 510(k) clearance, any subsequent modification of the device that could significantly affect its safety or effectiveness, or that would constitute a major change in its intended use, will require a new 510(k) clearance or require a PMA. In addition, the FDA may make substantial changes to industry requirements, including which devices are eligible for 510(k) clearance, which may significantly affect the process.

De novo classification process

If a new medical device does not qualify for the 510(k) pre-market notification process because no predicate device to which it is substantially equivalent can be identified, the device is automatically classified into Class III. The Food and Drug Administration Modernization Act of 1997 established a different route to market for low to moderate risk medical devices that are automatically placed into Class III due to the absence of a predicate device, called the “Request for Evaluation of Automatic Class III Designation,” or the de novo classification process. This process allows a manufacturer whose novel device is automatically classified into Class III to request down-classification of its medical device into Class I or Class II on the basis that the device presents low or moderate risk, rather than requiring the submission and approval of a PMA. If the manufacturer seeks reclassification into Class II, the manufacturer must include a draft proposal for special controls that are necessary to provide a reasonable assurance of the safety and effectiveness of the medical device. The FDA may reject the reclassification petition if it identifies a legally marketed predicate device that would be appropriate for a 510(k) or determines that the device is not low to moderate risk and requires PMA or that general controls would be inadequate to control the risks and special controls cannot be developed. Obtaining FDA marketing authorization, de novo down-classification, or approval for medical devices is expensive and uncertain, and may take several years, and generally requires significant scientific and clinical data.

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PMA process

The PMA process, including the gathering of clinical and nonclinical data and the submission to and review by the FDA, can take several years or longer. The applicant must prepare and provide the FDA with reasonable assurance of the device’s safety and effectiveness, including information about the device and its components regarding, among other things, device design, manufacturing, and labeling. PMA applications are subject to an application fee. In addition, PMAs for medical devices must generally include the results from extensive preclinical and adequate and well-controlled clinical trials to establish the safety and effectiveness of the device for each indication for which FDA approval is sought. In particular, for a diagnostic, the applicant must demonstrate that the diagnostic produces reproducible results. As part of the PMA review, the FDA will typically inspect the manufacturer’s facilities for compliance with the Quality Management System Regulation, which imposes extensive testing, control, documentation, and other quality assurance and GMP requirements.

Foreign regulation

In order to market any product outside of the United States, we would need to comply with numerous and varying regulatory requirements of other countries and jurisdictions regarding quality, safety, and efficacy and governing, among other things, clinical trials, marketing authorization, commercial sales and distribution of our products. Whether or not we obtain FDA approval for a product, we would need to obtain the necessary approvals by the comparable foreign regulatory authorities before we can commence clinical trials or marketing of the product in foreign countries and jurisdictions. Although many of the issues discussed above with respect to the United States apply similarly in the context of the European Union, the approval process varies between countries and jurisdictions and can involve additional product testing and additional administrative review periods. The time required to obtain approval in other countries and jurisdictions might differ from and be longer than that required to obtain FDA approval. Regulatory approval in one country or jurisdiction does not ensure regulatory approval in another, but a failure or delay in obtaining regulatory approval in one country or jurisdiction may negatively impact the regulatory process in others.

Other healthcare laws and compliance requirements

Pharmaceutical companies are subject to additional healthcare regulation and enforcement by the federal government and by authorities in the states and foreign jurisdictions in which they conduct their business, particularly once they have a commercialized product that is reimbursable by third-party payor programs. Such laws include, without limitation: the U.S. federal Anti-Kickback Statute, the civil False Claims Act, the federal Health Insurance Portability and Accountability Act of 1996, or HIPAA, and similar foreign, federal and state fraud and abuse, transparency and privacy laws.

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The U.S. federal Anti-Kickback Statute prohibits, among other things, persons and entities from knowingly and willfully soliciting, receiving, offering or paying remuneration, to induce, or in return for, either the referral of an individual, or the purchase or recommendation of an item or service for which payment may be made under any federal healthcare program. The term remuneration has been interpreted broadly to include anything of value, including stock options. There are a number of statutory exceptions and regulatory safe harbors protecting some common activities from prosecution, but they are drawn narrowly, and practices that involve remuneration, such as consulting agreements, that may be alleged to be intended to induce prescribing, purchasing or recommending may be subject to scrutiny if they do not qualify for an exception or safe harbor. Our practices may not in all cases meet all of the criteria for protection under a statutory exception or regulatory safe harbor. A person or entity does not need to have actual knowledge of the statute or specific intent to violate it in order to have committed a violation. Violations are subject to civil and criminal fines and penalties for each violation, plus up to three times the remuneration involved, imprisonment, and exclusion from government healthcare programs. In addition, a claim including items or services resulting from a violation of the U.S. federal Anti-Kickback Statute constitutes a false or fraudulent claim for purposes of the civil False Claims Act.

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Civil and criminal false claims laws, and civil monetary penalty laws, including the civil False Claims Act, which can be enforced through civil whistleblower or qui tam actions, prohibit, among other things, individuals or entities from knowingly presenting, or causing to be presented, claims for payment to the federal government, including federal healthcare programs, that are false or fraudulent. For example, the civil False Claims Act prohibits any person or entity from knowingly presenting, or causing to be presented, a false claim for payment to the federal government or knowingly making, using or causing to be made or used a false record or statement material to a false or fraudulent claim to the federal government.

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HIPAA created additional federal civil and criminal liability for, among other things, knowingly and willfully executing a scheme to defraud any healthcare benefit program, or obtain, by means of false or fraudulent pretenses, representations, or promises, any of the money or property owned by, or under the custody or control of, any healthcare benefit program, regardless of the payor (e.g., public or private) and knowingly and willfully falsifying, concealing, or covering up by any trick or device a material fact or making any materially false statements in connection with the delivery of, or payment for, healthcare benefits, items or services relating to healthcare matters. Similar to the U.S. federal Anti-Kickback Statute, a person or entity can be found guilty of violating HIPAA without actual knowledge of the statute or specific intent to violate it.

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HIPAA, as amended by the Health Information Technology for Economic and Clinical Health Act of 2009, or HITECH, and their respective implementing regulations, impose certain requirements on HIPAA covered entities, which include certain healthcare providers, healthcare clearing houses and health plans, and individuals and entities that provide services on their behalf that involve individually identifiable health information, known as business associates, relating to the privacy, security and transmission of individually identifiable health information, as well as their covered subcontractors. HITECH also created new tiers of civil monetary penalties, amended HIPAA to make civil and criminal penalties directly applicable to business associates, and gave state attorneys general new authority to file civil actions for damages or injunctions in federal courts to enforce the federal HIPAA laws and seek attorneys’ fees and costs associated with pursuing federal civil actions.

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The U.S. federal Physician Payments Sunshine Act requires certain manufacturers of drugs, devices, biologics and medical supplies for which payment is available under Medicare, Medicaid or the Children’s Health Insurance Program, with specific exceptions, to annually report to the Centers for Medicare and Medicaid Services, or CMS, information related to payments and other transfers of value made to physicians (defined to include doctors, dentists, optometrists, podiatrists and chiropractors), certain other licensed healthcare professionals (such as physician assistants and nurse practitioners), and teaching hospitals, as well as ownership and investment interests held by physicians and their immediate family members.

We may also be subject to additional similar U.S. state and foreign law equivalents of each of the above federal laws, such as anti-kickback and false claims laws which may apply to sales or marketing arrangements and claims involving healthcare items or services reimbursed by non-governmental third-party payors, including private insurers, or that apply regardless of payor, state laws which require pharmaceutical companies to comply with the pharmaceutical industry’s voluntary compliance guidelines and the relevant compliance guidance promulgated by the federal government, state and local laws which require pharmaceutical companies to report information related to payments and other transfers of value to physicians and other healthcare providers or marketing expenditures, state laws which require the reporting of information related to product pricing, state and local laws requiring the registration of pharmaceutical sales representatives, and state and foreign laws governing the privacy and security of health information which, in some cases, differ from each other in significant ways, and may not have the same effect, thus complicating compliance efforts. If our operations are found to be in violation of any of such laws or any other governmental regulations that apply, we may be subject to penalties, including, without limitation, significant civil, criminal and administrative penalties, damages, fines, exclusion from government-funded healthcare programs, such as Medicare and Medicaid or similar programs in other countries or jurisdictions, integrity oversight and reporting obligations to resolve allegations of non-compliance, disgorgement, imprisonment, contractual damages, reputational harm, diminished profits and the curtailment or restructuring of our operations.

Coverage and reimbursement

Significant uncertainty exists as to the coverage and reimbursement status of any pharmaceutical or biological product for which we obtain regulatory approval in the future. Sales of any product, if approved, depend, in part, on the extent to which such product will be covered by third-party payors, such as federal, state and foreign government healthcare programs, commercial insurance and managed healthcare organizations, and the level of reimbursement, if any, for such product by third-party payors. Decisions regarding whether to cover any of our product candidates, if approved, the extent of coverage and amount of reimbursement to be provided are made on a plan-by-plan basis. Further, no uniform policy for coverage and reimbursement exists in the United States, and coverage and reimbursement can differ significantly from payor to payor.

Third-party payors often rely upon Medicare coverage policy and payment limitations in setting their own reimbursement rates, but also have their own methods and approval process apart from Medicare determinations. As a result, the coverage determination process is often a time-consuming and costly process that will require us to provide scientific and clinical support for the use of our product candidates to each payor separately, with no assurance that coverage and adequate reimbursement will be applied consistently or obtained in the first instance.

Furthermore, it is possible that one or more of our product candidates may not be considered medically necessary or cost effective. A decision by a third-party payor not to cover any product candidates we may develop could reduce physician utilization of such product candidates once approved and have a material adverse effect on our sales, results of operations and financial condition.

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For products administered under the supervision of a physician, obtaining coverage and adequate reimbursement may be particularly difficult because of the higher prices often associated with such drugs. Additionally, separate reimbursement for the product itself or the treatment or procedure in which the product is used may not be available, which may impact physician utilization.

In addition, the U.S. government, state legislatures and foreign governments have continued implementing cost-containment programs, including price controls, restrictions on coverage and reimbursement and requirements for substitution of generic products. Third-party payors are increasingly challenging the prices charged for medical products and services, examining the medical necessity and reviewing the cost-effectiveness of pharmaceutical or biologics, medical devices and medical services, in addition to questioning safety and efficacy. Adoption of price controls and cost-containment measures, and adoption of more restrictive policies in jurisdictions with existing controls and measures, could further limit sales of any product that receives approval. Decreases in third-party reimbursement for any product or a decision by a third party not to cover a product could reduce physician usage and patient demand for the product. In addition, companion diagnostic tests require coverage and reimbursement separate and apart from the coverage and reimbursement for their companion pharmaceutical or biological products. Similar challenges to obtaining coverage and reimbursement, applicable to pharmaceutical or biological products, will apply to companion diagnostics.

Outside the United States, ensuring adequate coverage and payment for any biological candidates we may develop will face challenges. Pricing of prescription pharmaceuticals is subject to governmental control in many countries. Pricing negotiations with governmental authorities can extend well beyond the receipt of regulatory marketing approval for a product and may require us to conduct a clinical trial that compares the cost effectiveness of any product candidates we may develop to other available therapies. The conduct of such a clinical trial could be expensive and result in delays in our commercialization efforts. In the European Union, pricing and reimbursement schemes vary widely from country to country. Some countries provide that products may be marketed only after a reimbursement price has been agreed. Some countries may require the completion of additional studies that compare the cost-effectiveness of a particular product candidate to currently available therapies (so called health technology assessments) in order to obtain reimbursement or pricing approval. For example, the European Union provides options for its member states to restrict the range of products for which their national health insurance systems provide reimbursement and to control the prices of medicinal products for human use. European Union member states may approve a specific price for a product or it may instead adopt a system of direct or indirect controls on the profitability of the company placing the product on the market. Other member states allow companies to fix their own prices for products but monitor and control prescription volumes and issue guidance to physicians to limit prescriptions. Recently, many countries in the European Union have increased the amount of discounts required on pharmaceuticals and these efforts could continue as countries attempt to manage healthcare expenditures, especially in light of the severe fiscal and debt crises experienced by many countries in the European Union. The downward pressure on healthcare costs in general, particularly prescription products, has become intense. As a result, increasingly high barriers are being erected to the entry of new products. Political, economic and regulatory developments may further complicate pricing negotiations, and pricing negotiations may continue after reimbursement has been obtained. Reference pricing used by various European Union member states, and parallel trade (arbitrage between low-priced and high-priced member states), can further reduce prices. There can be no assurance that any country that has price controls or reimbursement limitations for pharmaceutical products will allow favorable reimbursement and pricing arrangements for any of our products, if approved in those countries.

Healthcare reform

The United States and some foreign jurisdictions are considering or have enacted a number of reform proposals to change the healthcare system. There is significant interest in promoting changes in healthcare systems with the stated goals of containing healthcare costs, improving quality or expanding access. In the United States, the pharmaceutical industry has been a particular focus of these efforts and has been significantly affected by federal and state legislative initiatives, including those designed to limit the pricing, coverage and reimbursement of pharmaceutical and biopharmaceutical products, especially under government-funded healthcare programs, and increased governmental control of drug pricing.

The ACA, which was enacted in 2010, substantially changed the way healthcare is financed by both governmental and private insurers in the United States, and significantly affected the pharmaceutical industry. In addition, other legislative and regulatory changes have been proposed and adopted in the United States since the ACA was enacted:

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The Budget Control Act of 2011 and subsequent legislation, among other things, created measures for spending reductions by Congress that include aggregate reductions of Medicare payments to providers of 2% per fiscal year, which remain in effect through 2032. Due to the Statutory Pay-As-You-Go Act of 2010, estimated budget deficit increases resulting from the American Rescue Plan Act of 2021, and subsequent legislation, Medicare payments to providers will be further reduced starting in 2025 absent further legislation. The U.S. American Taxpayer Relief Act of 2012 further reduced Medicare payments to several types of providers and increased the statute of limitations period for the government to recover overpayments to providers from three to five years.

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On April 13, 2017, CMS published a final rule that gives states greater flexibility in setting benchmarks for insurers in the individual and small group marketplaces, which may have the effect of relaxing the essential health benefits required under the ACA for plans sold through such marketplaces.

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On May 23, 2019, CMS published a final rule to allow Medicare Advantage Plans the option of using step therapy for Part B drugs beginning January 1, 2020.

Additionally, there has been heightened governmental scrutiny over the manner in which manufacturers set prices for their marketed products, which has resulted in several U.S. presidential executive orders, Congressional inquiries and proposed and enacted federal legislation designed to, among other things, bring more transparency to drug pricing, reduce the cost of prescription drugs under Medicare, and review the relationship between pricing and manufacturer patient programs. The Inflation Reduction Act of 2022, or the IRA, includes several provisions that may impact our business to varying degrees, including provisions that reduce the out-of-pocket spending cap for Medicare Part D beneficiaries from $7,050 to $2,000 starting in 2025, thereby effectively eliminating the coverage gap; impose new manufacturer financial liability on certain drugs under Medicare Part D, allow the U.S. government to negotiate Medicare Part B and Part D price caps for certain high-cost drugs and biologics without generic or biosimilar competition; require companies to pay rebates to Medicare for certain drug prices that increase faster than inflation; and delay until January 1, 2032 the implementation of the U.S. Department of Health and Human Services, or the HHS, rebate rule that would have limited the fees that pharmacy benefit managers can charge. The IRA permits HHS to implement many of these provisions through guidance, as opposed to regulation, for the initial years. Only high-expenditure single-source drugs that have been approved for at least 7 years (11 years for single-source biologics) can qualify for negotiation, with the negotiated price taking effect two years after the selection year. For 2026, the first year in which negotiated prices become effective, CMS selected 10 high-cost Medicare Part D drugs in 2023, negotiations began in 2024, and the negotiated maximum fair price for each drug has been announced. CMS has selected 15 additional Medicare Part D drugs for negotiated maximum fair pricing in 2027. For 2028, up to an additional 15 drugs, which may be covered under either Medicare Part B or Part D, will be selected, and for 2029 and subsequent years, up to 20 additional Part B or Part D drugs will be selected. HHS has and will continue to issue and update guidance as these programs are implemented. Various industry stakeholders have initiated lawsuits against the federal government asserting that the price negotiation provisions of IRA are unconstitutional. Additionally, the One Big Beautiful Bill Act (OBBBA), which was signed into law in July 2025, includes provisions that are expected to impact the U.S. healthcare system in various ways, including cuts to Medicaid and introducing new requirements for Medicaid coverage. The current administration also issued executive orders focused on decreasing prescription drug prices, including directing the Secretary of Health and Human Services to establish a mechanism through which American patients can buy drugs directly from manufacturers who sell at a most-favored-nation price and directing the U.S. Trade Representative and Secretary of Commerce to take action to ensure foreign countries are not engaged in practices that purposefully and unfairly undercut market prices and drive price hikes in the United States. In November 2025, CMS announced a voluntary initiative called the GENEROUS Model (GENErating cost Reductions fOr U.S. Medicaid Model) to introduce the option of most-favored-nation pricing to the Medicaid program, whereby a drug manufacturer may voluntarily offer supplemental rebates to participating state Medicaid programs for a manufacturer’s covered outpatient drugs. Government agreements with pharmaceutical companies and other government measures that use most-favored-nation pricing targets for prescription drugs, including the use of international pricing reference to set drug prices in the United States, or that increase generic drug and biosimilar entry sooner than expected, could materially harm the Company’s business, including with respect to its ability to set adequate pricing for new drugs to recover its research and development costs. It is currently unclear how the ongoing judicial challenges as well as other legislative, executive, and administrative actions, including how the IRA will be implemented, will impact the pharmaceutical industry. The implementation of cost containment measures or other healthcare reforms may prevent us from being able to generate revenue, attain profitability, or commercialize our product candidates if approved.

At the state level, legislatures have increasingly passed legislation and implemented regulations designed to control pharmaceutical product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access and marketing cost disclosure and transparency measures, and, in some cases, designed to encourage importation from other countries and bulk purchasing.

Employees and human capital resources

As of December 31, 2025, we had 59 full-time employees. Of our 59 full-time employees, 41 are engaged in research and development activities. None of our employees are represented by labor unions or covered by collective bargaining agreements. We consider our relationship with our employees to be good.

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Our human capital resources objectives include, as applicable, identifying, recruiting, retaining, incentivizing and integrating our employees. We believe our success depends on our ability to attract, retain, develop and motivate highly skilled personnel. In particular, we depend upon the personal efforts and abilities of the principal members of our senior management to partner effectively as a team, and to provide strategic direction, develop our business, manage our operations and maintain a cohesive and stable work environment. We also rely on qualified managers and skilled employees, such as scientists, medical professionals, engineers and laboratory technicians, with technical expertise in operations, scientific knowledge, engineering skills and quality management experience in order to operate our business successfully.

Our compensation program is designed to retain, motivate and, as needed, attract highly qualified employees. Accordingly, we use a mix of competitive base salary, performance-based equity compensation awards and other employee benefits.

Corporate Information

In February 2017, we were formed as a Delaware limited liability company under the name LEXEO Therapeutics, LLC. In November 2020, we converted into a Delaware corporation and were renamed Lexeo Therapeutics, Inc. Our principal executive offices are located at 345 Park Avenue South, Floor 6, New York, New York 10010, and our telephone number is (212) 547-9879.

Available Information

Our website address is www.lexeotx.com. The information contained on, or accessible through, our website is not incorporated by reference into this Annual Report. Our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and amendments to reports filed pursuant to Sections 13(a) and 15(d) of the Securities Exchange Act of 1934, as amended, or the Exchange Act, are filed with the SEC. Such reports and other information filed by us with the SEC are available free of charge on our website at ir.lexeotx.com when such reports are available on the SEC’s website. The SEC maintains an internet site that contains reports, proxy and information statements and other information regarding issuers that file electronically with the SEC at www.sec.gov. The information contained on the websites referenced in this Annual Report is not incorporated by reference into this filing. Further, our references to website URLs are intended to be inactive textual references only.

Channels of Distribution

We announce material information to the public through filings with the SEC, the investor relations page on our website, press releases, public conference calls, our LinkedIn account and webcasts in order to achieve broad, non-exclusionary distribution of information to the public and for complying with our disclosure obligations under Regulation FD. We encourage investors, the media, and others to follow the channels listed above and to review the information disclosed through such channels. Any updates to the list of disclosure channels through which we will announce information will be posted on the investor relations page on our website.