ORPHA:550
MELAS
Also known as: Mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes · Mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes · Mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes
Publications
9,802
Trials
26
Interventional, condition-specific
Researchers
1,035
Distinct authors in sample
Gene link
—
Readiness
5/6
Stages with a signal
Clinical definition (Orphanet)
A rare neurometabolic genetic disorder which is and multisystemic due to dysfunction and that is characterized by encephalomyopathy, lactic , and stroke-like episodes.
How rare: How common this is has not been clearly measured.
Cross-references
Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.
- MONDO:0010789
- MeSH:D017241
- OMIM:540000
- UMLS:C0162671
- NCIT:C84885
Additional Mondo synonyms (5)
MELAS syndrome · mitochondrial encephalomyopathy, lactic acidosis and stroke · mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes · mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes · mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes
Research stages
Trial readiness signals
Where this condition sits on an open-data research pipeline — not how close a treatment is, and not medical advice. Empty stages often mean “not in these databases under this Mondo ID,” not “impossible.”
5/6 stages with a signal
An interventional trial matched this condition name on ClinicalTrials.gov — see trials below.
- Gene identifiedNot found
No GenCC disease–gene assertion in this build
- LiteraturePresent
9,802 matched papers (5,258 in last 10 years) Source
- Phenotype characterisedPresent
112 HPO annotations (e.g. Encephalopathy; Bilateral tonic-clonic seizure; Myopathy) Source
- Animal modelPresent
1 genotype model (Mus musculus) Source
- Orphan designationPresent
2 FDA · 4 EMA designations (2 FDA orphan-indication approvals) — e.g. nicotinamide riboside Source
- Interventional trialPresent
26 matched on ClinicalTrials.gov (3 recruiting in sample)
Biology
Genes and phenotypes
Gene–disease validity from GenCC, plus phenotypes and animal models joined from Monarch Initiative via Mondo ID — not a clinical diagnosis aid.
Do we know what causes it?
Not yet — the cause hasn't been pinned down in GenCC.
No strong gene–disease assertion joined for this Orphanet entity.
Phenotypes (Monarch / HPO)
112
Associated phenotypes · MONDO:0010789
- Encephalopathy
- Bilateral tonic-clonic seizure
- Myopathy
- Arrhythmia
- Growth abnormality
Showing 5 of 112 — open Monarch for the full list.
Animal models (Monarch / Alliance)
1
Model associations linked to this Mondo ID
- mt-Tl1m1Jiha [background:] involves: C57BL/6NCrlj * CBA/JNCrlj·MGI:7614800·Mus musculus
Monarch fetch 2026-07-29
Therapies
Designations, candidates, and chemicals
FDA OOPD and EMA orphan designations, Open Targets clinical candidates, and CTD chemical associations via MyDisease.info. These never change the interventional-trial headline.
Orphan designation (FDA · EMA)
6
Designations · 2 with FDA orphan-indication approval
- FDA nicotinamide ribosideLACTIC ACIDOSIS Syndrome MELAS Mitochondrial encephalopathy Stroke-like episodes · 2017-01-25 · Not FDA Approved for Orphan Indication
- FDA idebenoneLACTIC ACIDOSIS Syndrome Encephalopathy MITOCHONDRIAL MYOPATHY MELAS Stroke-like episodes · 2009-05-22 · Not FDA Approved for Orphan Indication
- EMA 2-isopropyl-3H-naphtho[1,2-d]imidazole-4,5-dioneTreatment of mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes · 12/12/2017 · PositiveEMA designation
- EMA vatiquinoneTreatment of mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes · 24/02/2022 · WithdrawnEMA designation
- EMA sodium (4-{(E)-3-(4-fluorophenyl)-3-[4-(3-morpholin-4-yl-prop1ynyl)phenyl]allyloxy}-2-methylphenoxy)acetateTreatment of mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes · 21/08/2020 · WithdrawnEMA designation
- EMA (S)-6-hydroxy-2,5,7,8-tetramethyl-N-((R)-piperidin-3-yl)chroman-2-carboxamide hydrochlorideTreatment of mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes · 10/08/2015 · WithdrawnEMA designation
Sources: FDA OOPD · EMA orphan designations
Open Targets candidates
5
Drugs / clinical candidates · MONDO_0010789
- DICHLOROACETIC ACID·phase 2
- IDEBENONE·phase 2
- SONLICROMANOL·phase 2
- ZAGOCIGUAT·phase 2
- L-CITRULLINE·phase 1
CTD chemicals (MyDisease.info)
3 associated chemicals · 80 pathways. Therapeutic evidence is listed first when present — not a treatment recommendation.
- Dexamethasone · therapeutic
- Glutathione · marker/mechanism
- Valproic Acid · marker/mechanism
Pathways: Oxidative phosphorylation; Aminoacyl-tRNA biosynthesis; Metabolic pathways; Antifolate resistance; MAPK signaling pathway; Cytokine-cytokine receptor interaction; NF-kappa B signaling pathway; FoxO signaling pathway
Literature
Is anyone studying this?
9,802
9,802 papers — among the better-studied rare conditions, though still a fraction of common-disease literature (breast cancer: over 700,000). Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=3967) is 59.
9,802 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 59 (publications denominator n=3967).
5,258 in the last 10 years · low confidence
Phrase hits: 9,802 · MeSH hits: 36
Who's working on it?
1,035
Distinct author names in 200 sampled papers — named people below.
Who's working on it?
People publishing on this condition (sampled Europe PMC records). Affiliation is the most recent found in that sample.
- 01Zhao Y7 papers · 2025
Research Institute of Neuromuscular and Neurodegenerative Diseases and Department of Neurology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, No. 107 West Wenhua Road, Jinan, 250012, Shandong, China.
Papers in Europe PMC - 02Li Y5 papers · 2026
Department of Ophthalmology, Peking University People's Hospital, Beijing, China.
Papers in Europe PMC - 03Wang J5 papers · 2026
Research Institute of Neuromuscular and Neurodegenerative Diseases and Department of Neurology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, No. 107 West Wenhua Road, Jinan, 250012, Shandong, China.
Papers in Europe PMC - 04Wang W5 papers · 2026
Research Institute of Neuromuscular and Neurodegenerative Diseases and Department of Neurology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, No. 107 West Wenhua Road, Jinan, 250012, Shandong, China.
Papers in Europe PMC - 05Wang Z5 papers · 2026
Department of Neurology, Peking University First Hospital, Beijing, China.
Papers in Europe PMC - 06Zhang Y5 papers · 2025
Department of Neonatal Surgery, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China.
Papers in Europe PMC - 07Chen X4 papers · 2025
Department of Paediatrics, Haikou Affiliated Hospital of Central South University, Xiangya School of Medicine, Haikou, China.
Papers in Europe PMC - 08Horvath R4 papers · 2026
Department of Clinical Neurosciences, University of Cambridge, Cambridge CP2 0PY, UK.
Papers in Europe PMC - 09Ji K4 papers · 2026
Research Institute of Neuromuscular and Neurodegenerative Diseases and Department of Neurology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, No. 107 West Wenhua Road, Jinan, 250012, Shandong, China. jikunqian@email.sdu.edu.cn.
Papers in Europe PMC - 10Jiang H4 papers · 2025
Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou, China.
Papers in Europe PMC
Clinical research
Is a treatment being tested?
26
interventional trials for this specific condition
26 interventional trials matched this specific condition name; 3 currently recruiting in our sample.
Data as of 11 September 2026
26 interventional trials — more than 77.2% of diseases in the trials denominator have none at all (5501 of 7126; this disease is at the 95.6th percentile).
low confidence · 95.6th percentile (trials denominator)
Recruiting interventional trials
From the matched ClinicalTrials.gov set
26 interventional trials matched after quoted-phrase search and title/condition post-filter.
- NCT06451757·RECRUITING·KHENERFIN Study: A Trial to Evaluate the Efficacy and Safety of Sonlicromanol in Primary Mitochondrial Diseases
Not reviewed·Conditions: Mitochondrial Diseases · Maternally Inherited Diabetes and Deafness (MIDD) · Mitochondrial Encephalomyopathy, Lactic Acidosis and Stroke-like Episodes (MELAS) · Mitochondrial DNA tRNALeu(UUR) m.3243A<G Mutation·Matched via name phrase
- NCT06792500·NOT YET RECRUITING·A Basket Clinical Study to Assess Glycerol Tributyrate in Patients With Mitochondrial Encephalopathy, Lactic Acidosis, Stroke-like Episodes (MELAS) or Leber's Hereditary Optic Neuropathy-Plus (LHON-Plus)
Not reviewed·Conditions: MELAS Syndrome · Lebers Hereditory Optic Neuropathy With Extra Ocular Symptoms (LHON-Plus)·Matched via name + MeSH
- NCT06013397·NOT YET RECRUITING·Effectiveness of Ketogenic Diet in MELAS Syndrome
Not reviewed·Conditions: MELAS Syndrome · Ketogenic Dieting·Matched via name + MeSH
Observational and natural-history studies
5 observational studies match this condition. These do not test a treatment and are not counted in the interventional-trial headline, but they are genuine research: natural-history work often defines the endpoints needed for a future rare-disease trial, and families may be able to enroll.
Recruiting or not-yet-recruiting
- NCT01803906·ENROLLING BY INVITATION·Tissue Sample Study for Mitochondrial Disorders
Not reviewed·Conditions: Mitochondrial Disorders · Mitochondrial Disease · Melas · Kearns Sayer·Matched via name phrase
- NCT05554835·RECRUITING·Global Registry and Natural History Study for Mitochondrial Disorders
Not reviewed·Conditions: Mitochondrial Diseases · Kearns-Sayre Syndrome · MIDD · SANDO·Matched via name + MeSH
- NCT01532791·RECRUITING·Natural History Study - Mitochondrial Disease
Not reviewed·Conditions: MELAS or m.3243 A>G Mitochondrial DNA Mutation Carrier·Matched via name phrase
Other registries (secondary)
Broader net from EU CTIS, ISRCTN, and ICTRP when available — deduped against ClinicalTrials.gov IDs already counted above. Dual-model LLM relevance gates what we keep. These rows are not added to the interventional headline.
raw 10 · after dedupe 10 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 10 · dropped 0 · fetched 2026-07-29
Source notes: ictrp: Error: ICTRP public search unavailable (WHO portal is SPA-only; SOAP needs partnership). Tried: https://apps.who.int/tri
No secondary-registry studies passed dual-model relevance for this condition name (after dedupe).
Uncertain / not reviewed (10)
- ctis·2025-522361-30-00·Authorised, recruiting·A Phase III, randomised, double-blind, placebo-controlled, parallel-group, pivotal trial to assess the efficacy and safety of sonlicromanol in adult subjects with a genetically confirmed mitochondrial DNA tRNALeu(UUR) m.3243A>G variant.
skipped — LLM skipped (--skip-llm)
- ctis·2024-517514-15-00·Expired·An open-label extension study evaluating the safety of zagociguat in participants with MELAS who completed TIS6463-203
skipped — LLM skipped (--skip-llm)
- ctis·2023-506723-28-00·Cancelled·A Multi-Center, Randomized, Single-Blind, Placebo-Controlled Study to Assess the Efficacy, Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of Oral TTI-0102 for Treatment of Patients with Mitochondrial encephalomyopathy, lactic acidosis and strokelike episodes (MELAS).
skipped — LLM skipped (--skip-llm)
- ctis·2024-515389-15-00·Cancelled·Phase 2b randomized, double-blind, placebo-controlled crossover study evaluating the efficacy and safety of zagociguat in participants with MELAS (PRIZM)
skipped — LLM skipped (--skip-llm)
- ctis·2025-524367-20-00·Authorised, ongoing·An open-label, single-arm extension study to evaluate the long-term safety, tolerability, and efficacy of KL1333 (napazimone) in patients with primary mitochondrial disease
skipped — LLM skipped (--skip-llm)
- ctis·2022-500293-34-01·Authorised, recruiting·Phase I single arm, dose escalating and phase II double blind, randomized, placebo-controlled dose finding clinical trial assessing safety, and efficacy of intratracheal administration of allogeneic umbilical mesenchymal cells-derived extracellular vesicles in preventing bronchopulmonary dysplasia in extremely preterm newborns.
skipped — LLM skipped (--skip-llm)
- isrctn·ISRCTN56383373·No longer recruiting·Identification of the value of a novel test for the surveillance of women with precancerous lesions of the cervix who wish to avoid surgical treatment
skipped — LLM skipped (--skip-llm)
- isrctn·ISRCTN14126416·No longer recruiting·The role of abdominal muscle training in combination with pelvic floor muscle training to treat female urinary incontinence. A pilot study
skipped — LLM skipped (--skip-llm)
- isrctn·ISRCTN43372293·No longer recruiting·A dose-escalating clinical trial with KH176
skipped — LLM skipped (--skip-llm)
- isrctn·ISRCTN14485052·No longer recruiting·A trial of Nilvadipine in mild to moderate Alzheimer's disease
skipped — LLM skipped (--skip-llm)
Where to find support
Condition-specific patient organisations, when Orphanet lists them, are on the disease’s Orphanet page. We also link umbrella groups that support undiagnosed and ultra-rare families.
Orphanet entry for MELAS — check Associations / patient organisations on that page.
India — NPRD
Last verified 2026-07-26This ORPHAcode is not on our curated NPRD list (direct or Mondo-parent match). That does not decide clinical eligibility; families in India should ask a notified Centre of Excellence about current coverage.
Hand-curated for this project. ORPHAcode mappings are best-effort and may be incomplete or imprecise for umbrella categories. Parent (Mondo) matches mean the policy lists a broader category — confirm eligibility with a Centre of Excellence. Financial entitlements summarised from public policy statements and may change. This is not official government guidance.
How we counted this
Europe PMC query (preferred label + any corrected label + Orphanet and Mondo exact synonyms, stoplisted; unioned with resolved MeSH labels when available). UMLS / OMIM / NCIT cross-references are stored on the overview but are not added to the query string.
"MELAS" OR "Mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes" OR "Mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes" OR "Mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes" OR "MELAS syndrome" OR "mitochondrial encephalomyopathy, lactic acidosis and stroke" OR "mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes"
MeSH descriptor terms unioned into the query: MELAS Syndrome
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"MELAS" OR "Mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes" OR "Mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes" OR "Mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes" OR "MELAS syndrome" OR "mitochondrial encephalomyopathy, lactic acidosis and stroke" OR "mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes"
Interventional trials matched via: both, phrase (mesh = registered under a MeSH descriptor no name phrase would catch; recall-expansion = gene / selected parent terms used only for trials).
Study-type breakdown: 26 interventional · 5 observational · 0 expanded access. Only interventional studies enter the trial headline.
Query health: ok — strategies attempted: phrase, mesh; with hits: phrase, mesh
Run this search on ClinicalTrials.gov
Confidence reasoning
- Preferred label is short or not clearly distinctive
- No synonyms dropped by stoplist
- No label/synonym collisions with other diseases in this corpus
- Publication count (9802) is extremely high with unknown/missing prevalence — treat as possible over-matching, not proven research intensity
Ingested 2026-07-26T14:17:37.105Z