Leber hereditary optic neuropathy: Research & Drug Discovery Data

Drug discovery

drugs

With orphan designations

Overview

Leber hereditary optic neuropathy (LHON) is a maternally inherited mitochondrial disorder causing sudden, painless bilateral central vision loss, typically in adolescents/young adults. It results from mutations in mitochondrial DNA (e.g., MT-ND1, MT-ND4, MT-ND6), leading to retinal ganglion cell death and optic atrophy. While most carriers remain asymptomatic, affected individuals often progress to legal blindness (>20/200 acuity). LHON is the most common mitochondrial DNA disorder, with a male predominance [1][4][14][19].

Population

Affects ~1/27,000–1/54,000 in Europe, with lower rates in Australia/Serbia [4][7][19].
Male-to-female ratio ~3:1–5:1, though females account for 25% of cases [1][2][14].
Symptom onset peaks at 15–35 years, but 10% develop vision loss after age 50 [2][4][14].

Burden

~50% of affected males and 90% of females experience profound, permanent vision loss [4][14].
Associated with 2-fold increased mortality risk and higher rates of stroke, dementia, and cardiac defects [9][14].
Chronic disability impacts education/employment; 95% require lifelong low-vision support [4][16][19].

Therapies

Idebenone: Antioxidant approved in EU/USA; modest efficacy if started within 12 months of onset [4][18].
Gene therapy: GS011 (rAAV2/2-ND4) shows partial bilateral vision improvement in G11778A mutation trials [3][18].
Preventive measures: Mitochondrial replacement therapy for female carriers; avoidance of smoking/alcohol [8][13].

Categories: rare genetic diseases, rare inborn errors of metabolism, rare ophthalmic disorders

Research Papers

528 drug discovery papers about Leber hereditary optic neuropathy, with 2 first-in-class and 26 next-in-class emerging drug candidates forecasted to outperform the average preclinical success rate. Recent publications:

2026-07-07 | When LHON Mimics Demyelination: Area Postrema Syndrome in Biallelic DNAJC30 Variants

Introduction: Biallelic pathogenic variants in DNAJC30 cause an autosomal recessive form of Leber hereditary optic neuropathy (LHONAR1), traditionally considered a mitochondrially transmitted disorder. The phenotypic spectrum of diseases linked to DNAJC30 includes isolated optic neuropathy, Leigh syndrome spectrum (LSS), and atypical LHON-plus. Case description: Here, we report a 13-year-old boy presenting symptoms of area postrema syndrome (APS), with recurrent vomiting, vertigo, nystagmus, and subacute visual deterioration with central scotoma. Ophthalmological examination revealed bilateral papilledema with telangiectatic vessels, while visual evoked potentials demonstrated severe bilateral optic pathway dysfunction. Brain magnetic resonance imaging (MRI) showed T2/FLAIR hyperintense lesions involving the area postrema and enhancement of the optic nerves, strongly suggesting seronegative neuromyelitis optica spectrum disorder (NMOSD). Extensive immunological and cerebrospinal fluid studies, including anti-aquaporin-4 (AQP4) and anti-MOG antibodies, were negative. High-dose corticosteroids and intravenous immunoglobulins resulted in only transient and incomplete improvement, followed by further visual decline. Additionally, laboratory tests detected elevated lactate plasma levels. Hence, whole-exome sequencing was performed, which identified a homozygous pathogenic DNAJC30 c.152A>G, p.(Tyr51Cys) variant, associated with LHONAR1. After initiation of idebenone therapy, the patient showed significant improvement in visual function, normalization of lactate levels, and complete resolution of the brainstem lesions on follow-up MRI. Conclusions: This case further expands the neuro-ophthalmic spectrum associated with DNAJC30 variants and suggests that DNAJC30-related disease may closely mimic seronegative NMOSD. We highlight that early genetic diagnosis is essential, as recognition of this mitochondrial etiology enables targeted therapy and may substantially improve clinical outcomes.

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2026-06-27 | Clinical development in primary mitochondrial diseases at a translational inflection point: Lessons, mechanisms, and emerging therapeutic strategies.

Clinical development for primary mitochondrial diseases (PMDs) has spanned more than two decades, yet therapeutic success remains limited. In this Review, we provide a comprehensive, pharmacology-focused analysis of the PMD clinical trial landscape and identify key mechanistic and translational determinants underlying recent progress. A systematic survey of ClinicalTrials.gov covering January 2010 to April 2026 identified 159 registered studies across PMD subtypes after deduplication, including 110 interventional trials. Progress has been constrained by marked genetic and phenotypic heterogeneity, small and geographically dispersed patient populations, and the lack of validated pharmacodynamic and disease-specific endpoints. Consequently, several well-designed late-stage trials have yielded negative or inconclusive outcomes, and regulatory approvals have historically been scarce. Recent advances, however, indicate a shift in trajectory. Four therapies have achieved regulatory authorization, including idebenone for Leber hereditary optic neuropathy, taurine for MELAS, and recent FDA approvals of doxecitine and doxribtimine (Kygevvi) for thymidine kinase 2 deficiency and elamipretide (FORZINITY) for Barth syndrome. These successes share a convergent translational framework integrating mechanism-based pharmacology, genotype-driven patient selection, and biologically aligned endpoints. Clinical activity has also accelerated, with approximately half of PMD interventional trials initiated since 2020 and 50 studies currently active or recruiting. Emerging strategies include NAD⁺ augmentation, soluble guanylate cyclase stimulation, mTOR modulation, gene therapies, and heteroplasmy-targeting approaches. Collectively, these advances mark an emerging inflection point and suggest a path toward greater regulatory success in the coming decade.

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2026-06-09 | Long-term Safety of Idebenone in Patients With Leber Hereditary Optic Neuropathy With Alcohol or Tobacco Use/Abuse or Vitamin B12 Deficiency: Results From the PAROS Study (P10-17.006)

To describe, from the PAROS study, real-world long-term idebenone safety in patients with Leber hereditary optic neuropathy (LHON) and a history of alcohol or tobacco use/abuse or vitamin B12 deficiency.

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2026-07-07 | When LHON Mimics Demyelination: Area Postrema Syndrome in Biallelic DNAJC30 Variants

Open article ↗

2026-06-27 | Clinical development in primary mitochondrial diseases at a translational inflection point: Lessons, mechanisms, and emerging therapeutic strategies.

Open article ↗

2026-06-09 | Long-term Safety of Idebenone in Patients With Leber Hereditary Optic Neuropathy With Alcohol or Tobacco Use/Abuse or Vitamin B12 Deficiency: Results From the PAROS Study (P10-17.006)

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Drug Discovery Landscape

10 orphan drug designations for Leber hereditary optic neuropathy, including 1 approved therapy.

Drug	Therapy type	Regulator	Orphan designation	Approval	Sponsor
oral small-molecule modulator targeted NQO1	small molecules	FDA	2026-05-21	—	Curome Biosciences Co., Ltd.
Adeno-associated virus vector serotype 2 expressing the human MT-ND4 codon-optimised gene	gene therapies	EMA	2022-01-14	—	PPD Bulgaria EOOD
recombinant adeno-associated virus serotype 2 containing human mitochondrial ND1 codon optimized gene (rAAV2-ND1)	gene therapies	FDA	2022-01-13	—	Neurophth Therapeutics, Inc.
[10-(4,5-dimethyl-3,6-dioxocyclohexa-1,4-dien-1-yl)decyl](triphenyl)phosphonium bromide	small molecules	FDA	2021-11-04	—	Mitotech S.A.
Recombinant Human Adeno-Associated Virus Serotype 2 Containing Human Mitochondrial ND4 gene (rAAV2-ND4)	gene therapies	FDA	2020-09-22	—	Neurophth Therapeutics, Inc.
elamipretide	small molecules	FDA	2018-04-02	—	Stealth BioTherapeutics Inc.
lenadogene nolparvovec	gene therapies	FDA	2013-11-20	—	Gensight Biologics
Adeno-associated viral vector containing the human NADH dehydrogenase 4 gene	gene therapies	EMA	2011-05-13	—	GenSight- Biologics
Idebenone [Raxone]	small molecules	EMA	2007-02-15	2015-09-10	Chiesi Farmaceutici S.p.A.
idebenone	small molecules	FDA	2006-10-31	—	Chiesi Farmaceutici S.p.A.

Leber hereditary optic neuropathy

Leber hereditary optic neuropathy

Leber hereditary optic neuropathy

Overview

Population

Burden

Therapies

Categories: rare genetic diseases, rare inborn errors of metabolism, rare ophthalmic disorders

Research Papers

2026-07-07 | When LHON Mimics Demyelination: Area Postrema Syndrome in Biallelic DNAJC30 Variants

2026-06-27 | Clinical development in primary mitochondrial diseases at a translational inflection point: Lessons, mechanisms, and emerging therapeutic strategies.

2026-06-09 | Long-term Safety of Idebenone in Patients With Leber Hereditary Optic Neuropathy With Alcohol or Tobacco Use/Abuse or Vitamin B12 Deficiency: Results From the PAROS Study (P10-17.006)

2026-07-07 | When LHON Mimics Demyelination: Area Postrema Syndrome in Biallelic DNAJC30 Variants

2026-06-27 | Clinical development in primary mitochondrial diseases at a translational inflection point: Lessons, mechanisms, and emerging therapeutic strategies.

2026-06-09 | Long-term Safety of Idebenone in Patients With Leber Hereditary Optic Neuropathy With Alcohol or Tobacco Use/Abuse or Vitamin B12 Deficiency: Results From the PAROS Study (P10-17.006)

Drug Discovery Landscape

Updated: Aug 23, 2026