Inclusion Criteria:

• Participant must be male or female, ≥ 18 to ≤ 40 years of age at the time of signing the informed consent.
• Participants who have a confirmed diagnosis of FA, based on clinical phenotype and genotype (GAA expansion on both alleles), with onset of FA EHIRUHDJH \HDUV.
• No contraindications to undergoing cardiac biopsies.
• Participants who are able to perform CPET using arm ergometry and achieve a peak respiratory exchange ratio (RER) ≥ 1.0 and peak oxygen consumption (VO2) ≥ 10 and ≤ 20 mLxO2 kg-1x min-1 at a minimum of 40 revolutions per minute.
• LVEF measured  by cardiac MRI ≥ 45%.
• Left ventricular hypertrophy (LVH) on cardiac MRI, defined as left ventricular mass index (LVMi) > 85 gm/m^2 for males and > 68 gm/m^2 for females.
• Stroke volume index (≤ 45 mL/m^2 ) and/or global longitudinal left ventricular strain (≥-20 %), on cardiac MRI.
• Focal fibrosis on cardiac MRI ≤ 5% of wall mass.
• Neutralizing anti-AAVrh.10 titer < 1:40.
• Normal liver monitoring tests (ALT, AST, GGT, ALP, bilirubin); normal AFP; normal hemoglobin, white blood cells (WBCs), platelets; normal prothrombin time (PT), partial thromboplastin time (PTT), normal liver ultrasound; no underlying liver disease; e.g., non-alcoholic steatohepatitis (NASH), or history of liver disease; e.g., hepatitis B or C.
• Normal kidney function measured by creatinine and blood urea nitrogen (BUN) and estimated glomerular filtration rate > 60 mL/min as calculated by the equation from the Modification of Diet in Renal Disease (MDRD) Study using creatinine, age, sex, and ethnicity.
• Vital signs that are in the following ranges:
  • Blood pressure: 90/60 mm Hg to 140/90 mm Hg;
  • Respiratory rate: 12 to 24 breaths per minute;
  • Heart rate: 60 to 110 beats per minute;
  • Temperature 97.7ºF to 99.7ºF (3.65ºC to 37.6ºC);
  • Pulse oximetry ≥ 95%.
• No evidence of active infection of any type, including hepatitis virus (A, B or C) or HIV-1 and HIV-2, or undergoing treatment for any viral infections.
• Participants must be fully vaccinated for COVID-19 and meningococcal disease. Participants who had prior COVID-19 infection can join the study if they have no residual cardiopulmonary COVID-19-related abnormalities and normal pulse oximetry.
• Participants must be willing to complete all study assessments and procedures and to communicate effectively with the investigator and site staff.
• Fertile individuals are required to utilize birth control measures to prevent pregnancy for the duration of the study:
  • Male participants:  refer to Contraceptive and Barrier Guidance;
  • Female participants: refer to Contraceptive and Barrier Guidance for definitions for women of childbearing potential (WOCBP) and women of non-childbearing potential (WONCBP). 
• Capable of giving signed informed consent which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in this protocol.
• Participants who agree not to post their personal medical data in relation to this study or any study information online including social media sites until all participants have completed all LX2006 clinical studies, including LTFU.

Exclusion Criteria:

• Any history of coronary artery disease or any structural heart or vascular disease, including but not limited to aortic stenosis and hypertrophic obstructive cardiomyopathy, other than FA cardiomyopathy.
• History of hemodynamically unstable arrhythmias requiring physician intervention.
• History of thromboembolic phenomenon or increased risk of thromboembolic phenomenon based on prior laboratory results (e.g., protein S, protein C, antithrombin, factor V, prothrombin gene mutations) or any hospitalization within the last 90 days
• History of clinically significant lung function abnormality such as chronic obstructive pulmonary disease (COPD) and emphysema.
• A history of a clinically significant allergic reaction or hypersensitivity, as judged by the investigator, to any drug or any component of the study drug formulations or to corticosteroids that are used in the study.
• Uncontrolled psychiatric disease (e.g., uncontrolled major depressive disorder).
• Uncontrolled diabetes (Hemoglobin A1c [HbA1c] levels > 7%.
• A history of drug abuse or alcohol abuse within the past year as judged by the investigator.
• Any malignancy during the last five years, except basal cell skin cancer.
• A history of major surgery or significant trauma within 4 weeks or minor surgery within 2 weeks of Screening.
• Any flu-like syndrome, respiratory or other viral infection within 4 weeks of Day 1 or vaccination with attenuated live virus within 4 months of Day 1.
• Participants who are receiving systemic corticosteroids or other immunosuppressive medications.
• Participants who have had a change in dose (start/stop/change) of cardiac medication within 12 weeks prior to Screening.
• Participation in an investigational drug or device study within 12 weeks prior to Screening or any previous gene therapy or cell therapy at any time prior to Screening.
• Participants with a contraindication to cardiac MRI (e.g., non-MRI compatible pacemaker/defibrillator) or gadolinium (known or suspected hypersensitivity).
• On ECG, a corrected QT interval, Fridericia’s formula (QTcF) > 450 ms in men and > 460 ms in women or the presence of clinically significant abnormalities as determined by the investigator, other than ECG abnormalities related to FA.
• Females who are pregnant or breastfeeding.
• Other prior or ongoing medical condition or treatment, physical finding, or laboratory abnormality that, in the investigator's opinion, could adversely affect the safety of the participant, interfere with the participant’s compliance with the protocol, or impair the assessment and interpretation of study results.

Eligibility last updated 3/21/22. Questions regarding updates should be directed to the study team contact.