Friedreich ataxia (FA / FRDA)

What changes during this transition

Friedreich ataxia is the most common hereditary ataxia — an autosomal recessive progressive neurodegenerative disease caused by biallelic GAA trinucleotide repeat expansions in intron 1 of the FXN gene on chromosome 9q21.11. Normal alleles carry 5-33 GAA repeats; pathologic alleles carry 70-1000+, typically 600-1200 in affected patients. Expanded repeats silence FXN transcription and produce frataxin protein deficiency. Frataxin is essential for mitochondrial iron-sulfur cluster assembly, which in turn is essential for oxidative phosphorylation complexes, aconitase, and Krebs cycle enzymes. Frataxin deficiency causes mitochondrial iron accumulation, oxidative stress, and progressive degeneration in dorsal root ganglia, spinocerebellar and corticospinal tracts, the dentate nucleus of the cerebellum, cardiac muscle, and pancreatic β-cells. Incidence is roughly 1/40,000-50,000 in European populations with a carrier frequency near 1/85. Typical onset is 5-25 years (mean 10-15); later-onset Friedreich ataxia (LOFA, >25 years) and very-late-onset (VLOFA, >40) generally correlate with shorter repeats. Clinical features: progressive gait ataxia combining cerebellar and sensory components, dysarthria, dysmetria, loss of deep tendon reflexes (Achilles especially), extensor plantar responses, loss of vibration and proprioception from dorsal column involvement, muscle weakness and atrophy, near-universal scoliosis, and pes cavus foot deformity. Hypertrophic cardiomyopathy develops in ~60% of patients — concentric LVH progressing to dilated cardiomyopathy, arrhythmias, and heart failure — and is the leading mortality driver. Diabetes mellitus develops in ~30%, insulin-deficient from β-cell mitochondrial failure rather than T2D-pattern insulin resistance. Optic atrophy, sensorineural hearing loss, bladder dysfunction, and executive dysfunction can also appear; broader cognition is typically preserved. Most patients become wheelchair-dependent 10-15 years after onset, often by ages 25-30. Historical median survival is around 37 years; modern multidisciplinary care with cardiac management is extending this. Diagnosis combines clinical neurology, nerve conduction studies (axonal sensory neuropathy), brain and spinal MRI (cord atrophy, cerebellar atrophy), ECG, echocardiogram, and cardiac MRI for HCM, HbA1c for diabetes, and FXN GAA repeat analysis as the gold standard. Standard of care is multidisciplinary: neurology for ataxia management, cardiology for HCM and arrhythmias, endocrinology for diabetes, PT/OT and speech therapy, orthopedic management of scoliosis, ophthalmology, audiology, and pulmonology in later stages. The historic moment in Friedreich ataxia care came in February 2023 when the FDA approved omaveloxolone (Skyclarys, Reata Pharmaceuticals/Biogen) — an Nrf2 (nuclear factor erythroid 2-related factor 2) activator — for FA patients aged 16 and older, the first FDA-approved therapy in the 50+ year history of the disease. EMA approval followed in February 2024. Omaveloxolone does not restore frataxin but activates the Nrf2 antioxidant pathway, restoring mitochondrial function and reducing oxidative stress; the MOXIe trial demonstrated significant improvement on the modified Friedreich Ataxia Rating Scale (mFARS). Adverse effects include transaminase elevation (requiring LFT monitoring), headache, nausea, abdominal pain, fatigue, and decreased appetite. Access remains a real issue given list pricing. Several disease-modifying programs are advancing: multiple AAV-based gene therapy programs targeting frataxin replacement, vatiquinone (EPI-743, Reata) with Phase 3 MOVE-FA readouts emerging as a mitochondrial protectant, and histone deacetylase inhibitor trials aimed at increasing FXN transcription. Cardiac management with ACE inhibitors, beta-blockers, ICDs for arrhythmias, and heart failure management is standard. Diabetes management is insulin-based, often with CGM. The Friedreich's Ataxia Research Alliance (FARA, curefa.org), Friedreich's Ataxia Parents Group, Ataxia UK, Euroataxia, and the National Ataxia Foundation are an advocacy-active community. Editorial substrate posture: FA is fundamentally a mitochondrial disease, which makes peptide-curious community interest understandable — NAD+ precursor framing (NMN/NR) lands on FA more biologically than on most conditions, muscle-weakness framing brings GH-axis peptides into the conversation, and cardiomyopathy and diabetes presence raises legitimate safety questions about layering uncharacterized agents. Substrate honors the real curiosity, names omaveloxolone explicitly as the disease-modifying option the FA community deserves to know about, and frames every peptide question as a conversation for the multidisciplinary FA team rather than a parallel decision made independently. Cognition is preserved; patients live full mental lives with progressive physical disability and deserve editorial honesty, not hedged community framing. Seventy-sixth deliberate non-elevation of community peptides.