RARE DISEASERESEARCH ATLAS

ORPHA:308425

Methylmalonic acidemia due to methylmalonyl-CoA epimerase deficiency

low confidenceDisorder

Also known as: MCEE deficiency · Methylmalonic acidemia due to methylmalonyl-CoA racemase deficiency · Methylmalonic aciduria due to methylmalonyl-CoA epimerase deficiency · Methylmalonic aciduria due to methylmalonyl-CoA racemase deficiency

Query health: suspect — Only one of 2 strategies returned hits (phrase).

Publications

654

Trials

0

Interventional, condition-specific

Researchers

113

Distinct authors in sample

Gene link

MCEE

Definitive

Readiness

4/6

Stages with a signal

Clinical definition (Orphanet)

Methylmalonic acidemia due to methylmalonyl-CoA epimerase deficiency is a rare inborn error of metabolism disease characterized by mild to moderate, persistent elevation of methylmalonic acid in plasma, urine and cerebrospinal fluid. Clinical presentation may include acute decompensation with (presenting with vomiting, dehydration, confusion, hallucinations), nonspecific neurological symptoms, or may also be asymptomatic.

How rare: <1 / 1 000 000 — fewer than one in a million. In a city the size of Kolkata, that might mean on the order of fifteen people.

Orphanet entry

Cross-references

Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.

Additional Mondo synonyms (4)

methylmalonic acidemia due to methylmalonyl-CoA epimerase deficiency · methylmalonic acidemia due to methylmalonyl-CoA racemase deficiency · methylmalonic aciduria due to methylmalonyl-CoA epimerase deficiency · methylmalonic aciduria due to methylmalonyl-CoA racemase deficiency

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.”

4/6 stages with a signal

No specific-condition interventional trial, but broader-category trials exist — discuss eligibility with a clinician.

  1. Gene identifiedPresent

    Definitive — MCEE

  2. LiteraturePresent

    654 matched papers (530 in last 10 years) Source

  3. Phenotype characterisedPresent

    10 HPO annotations (e.g. Dehydration; Hyperhomocystinemia; Spasticity) Source

  4. Animal modelNot found

    No Alliance genotype “model of” associations via Monarch for these Mondo IDs

  5. Orphan designationNot found

    No FDA or EMA orphan-drug designation matched this disease via UMLS or preferred name Source

  6. Interventional trialPartial

    None under the specific name; 15 for broader category methylmalonic acidemia

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?

Yes — we know a specific gene responsible (MCEE).

GenCC classification: Definitive.

Phenotypes (Monarch / HPO)

10

Associated phenotypes · MONDO:0009615

  • Dehydration
  • Hyperhomocystinemia
  • Spasticity
  • Metabolic acidosis
  • Methylmalonic aciduria

Showing 5 of 10 — open Monarch for the full list.

Animal models (Monarch / Alliance)

None returned for this Mondo ID. Empty here is not proof that no model organism work exists under another name or gene.

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)

No designation matched this disease via UMLS or preferred name on the FDA OOPD mirror or EMA orphan register. Absence here is not proof that none exists under another wording.

Open Targets candidates

No drugs or clinical candidates returned for this Mondo ID on Open Targets.

CTD chemicals (MyDisease.info)

No CTD chemical associations returned for this Mondo ID.

Literature

Is anyone studying this?

654

654 papers have been published on this condition. That is a real research literature — still far smaller than common diseases (breast cancer: over 700,000 papers). Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=3967) is 59.

654 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).

530 in the last 10 years · low confidence

Phrase hits: 11 · MeSH hits: 0

Open Europe PMC search

Who's working on it?

113

Distinct author names in 11 sampled papers — named people below.

Who's working on it?

No interventional trial matched this name; these authors publish on it in the sampled literature — a practical starting point for contact.

  1. 01
    Baumgartner MR3 papers · 2021

    Division of Metabolism and Children's Research Center, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland.

    Papers in Europe PMC
  2. 02
    Bailey HJ2 papers · 2019

    Structural Genomics Consortium, Nuffield Department of Medicine, University of Oxford, Old Road Campus Research Build, Roosevelt Dr, Oxford, OX3 7DQ, UK.

    Papers in Europe PMC
  3. 03
    Burda P2 papers · 2019

    Division of Metabolism and Children's Research Center, University Children's Hospital, Steinwiesstrasse 75, CH-8032 Zurich, Switzerland.

    Papers in Europe PMC
  4. 04
    Bürer C2 papers · 2019

    Division of Metabolism and Children's Research Center, University Children's Hospital, Steinwiesstrasse 75, CH-8032 Zurich, Switzerland.

    Papers in Europe PMC
  5. 05
    Chaikuad A2 papers · 2019

    Structural Genomics Consortium, Nuffield Department of Medicine, University of Oxford, Old Road Campus Research Build, Roosevelt Dr, Oxford, OX3 7DQ, UK.

    Papers in Europe PMC
  6. 06
    Fowler B2 papers · 2019

    Division of Metabolism and Children's Research Center, University Children's Hospital, Steinwiesstrasse 75, CH-8032 Zurich, Switzerland.

    Papers in Europe PMC
  7. 07
    Froese DS2 papers · 2019

    Division of Metabolism and Children's Research Center, University Children's Hospital, Steinwiesstrasse 75, CH-8032 Zurich, Switzerland.

    Papers in Europe PMC
  8. 08
    Heuberger K2 papers · 2019

    Division of Metabolism and Children's Research Center, University Children's Hospital, Steinwiesstrasse 75, CH-8032 Zurich, Switzerland.

    Papers in Europe PMC
  9. 09
    Krysztofinska E2 papers · 2019

    Structural Genomics Consortium, Nuffield Department of Medicine, University of Oxford, Old Road Campus Research Build, Roosevelt Dr, Oxford, OX3 7DQ, UK.

    Papers in Europe PMC
  10. 10
    Lutz S2 papers · 2019

    Division of Metabolism and Children's Research Center, University Children's Hospital, Steinwiesstrasse 75, CH-8032 Zurich, Switzerland.

    Papers in Europe PMC

Clinical research

Is a treatment being tested?

0

interventional trials for this specific condition

No interventional trial testing a treatment matched this specific condition name on ClinicalTrials.gov (observational studies and pan-disease registries are listed separately when present). 15 trials are registered for methylmalonic acidemia, the broader category — shown separately because they may or may not enrol this specific subtype.

Data as of 11 September 2026 · last trial check 11 September 2026

No matched interventional trials. This is true for 77.2% of diseases in the trials denominator (5501 of 7126). Here are the researchers publishing on it.

low confidence · 38.6th percentile (trials denominator)

Recruiting interventional trials

From the matched ClinicalTrials.gov set

No interventional trial testing a treatment was found for this specific condition name on ClinicalTrials.gov.

15 interventional trials matched methylmalonic acidemia, the broader category — listed below. Those studies are not counted in the condition-specific total.

Broader category: methylmalonic acidemia

15

Interventional trials for the parent category, exclusive of NCT IDs already counted above. Eligibility for this subtype is not guaranteed.

Worth raising with a clinician. How we count trials.

Recruiting under the broader category

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 0 · after dedupe 0 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 0 · dropped 0 · fetched 2026-07-30

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).

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 Methylmalonic acidemia due to methylmalonyl-CoA epimerase deficiency — check Associations / patient organisations on that page.

India — NPRD

Last verified 2026-07-26

Likely covered — the policy lists Methylmalonic acidemia as a category (Group 2), and this condition is a form of it. Confirm eligibility with a Centre of Excellence.

Group 2 — long-term / lifelong lower-cost interventions

NPRD envisages State Government support for dietary formulae, hormones, and other lower-cost interventions. This is a different route from the central CoE ₹50 lakh pathway; ask your state health department and a CoE which channel applies.

Central CoE funding may also apply depending on current rules — confirm with a notified Centre of Excellence. Do not assume the ₹50 lakh ceiling covers Group 2 by default. Verify

Centres of Excellence (15)
  • All India Institute of Medical Sciences (AIIMS)New Delhi, Delhi
  • Maulana Azad Medical CollegeNew Delhi, Delhi
  • Sanjay Gandhi Post Graduate Institute of Medical SciencesLucknow, Uttar Pradesh
  • Post Graduate Institute of Medical Education and Research (PGIMER)Chandigarh, Chandigarh
  • Centre for DNA Fingerprinting & Diagnostics with Nizam’s Institute of Medical SciencesHyderabad, Telangana
  • King Edward Memorial HospitalMumbai, Maharashtra
  • Institute of Post-Graduate Medical Education and Research (IPGMER)Kolkata, West Bengal
  • Centre for Human Genetics with Indira Gandhi HospitalBengaluru, Karnataka
  • Institute of Child Health and Hospital for Children (ICH & HC)Chennai, Tamil Nadu
  • All India Institute of Medical Sciences (AIIMS)Jodhpur, Rajasthan
  • Sree Avittam Thirunal Hospital (SAT), Government Medical CollegeThiruvananthapuram, Kerala
  • All India Institute of Medical Sciences (AIIMS)Bhopal, Madhya Pradesh
  • Regional Institute of Medical Sciences (RIMS)Imphal, Manipur
  • All India Institute of Medical Sciences (AIIMS)Patna, Bihar
  • Assam Medical College & HospitalDibrugarh, Assam

Voluntary contributions / crowdfunding (separate from CoE funding): https://rarediseases.mohfw.gov.in/

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.

("Methylmalonic acidemia due to methylmalonyl-CoA epimerase deficiency" OR "MCEE deficiency" OR "Methylmalonic acidemia due to methylmalonyl-CoA racemase deficiency" OR "Methylmalonic aciduria due to methylmalonyl-CoA epimerase deficiency" OR "Methylmalonic aciduria due to methylmalonyl-CoA racemase deficiency") OR (MESH:"Methylmalonyl-CoA Epimerase Deficiency") OR ("MCEE" OR "MCEE syndrome" OR "MCEE-related")

Run this search on Europe PMC

MeSH descriptor terms unioned into the query: Methylmalonyl-CoA Epimerase Deficiency

ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):

"Methylmalonic acidemia due to methylmalonyl-CoA epimerase deficiency" OR "MCEE deficiency" OR "Methylmalonic acidemia due to methylmalonyl-CoA racemase deficiency" OR "Methylmalonic aciduria due to methylmalonyl-CoA epimerase deficiency" OR "Methylmalonic aciduria due to methylmalonyl-CoA racemase deficiency" OR "Methylmalonyl-CoA Epimerase Deficiency"

Study-type breakdown: 0 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.

Parent-category trials query:

"methylmalonic acidemia"

Query health: suspect — strategies attempted: phrase, mesh; with hits: phrase

Run this search on ClinicalTrials.gov

Confidence reasoning

  • Preferred label is multi-word and distinctive
  • No synonyms dropped by stoplist
  • No label/synonym collisions with other diseases in this corpus
  • Publication count (654) is implausibly high for prevalence class "<1 / 1 000 000" — treat as possible over-matching, not a measure of research intensity

Ingested 2026-07-27T12:52:09.369Z