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ORPHA:35708

Aromatic L-amino acid decarboxylase deficiency

low confidenceDisorder

Also known as: AADC deficiency

Publications

729

Trials

7

Interventional, condition-specific

Researchers

1,120

Distinct authors in sample

Gene link

DDC

Definitive

Readiness

6/6

Stages with a signal

Clinical definition (Orphanet)

A rare, severe, genetic neurometabolic disorder associated with clinical manifestations related to impaired synthesis of dopamine, noradrenaline, adrenaline and serotonin. Clinical manifestations are typically characterized by early-onset muscular , movement disorders (oculogyric crisis, dystonia), , ptosis and non-motor symptoms (sleep disturbance, irritability, excessive sweating, and nasal congestion).

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 (2)

aromatic L-amino acid decarboxylase deficiency · aromatic L-amino-acid decarboxylase 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.”

6/6 stages with a signal

An interventional trial matched this condition name on ClinicalTrials.gov — see trials below.

  1. Gene identifiedPresent

    Definitive — DDC

  2. LiteraturePresent

    729 matched papers (572 in last 10 years) Source

  3. Phenotype characterisedPresent

    75 HPO annotations (e.g. Hyperhidrosis; Seizure; Dystonia) Source

  4. Animal modelPresent

    1 genotype model (Mus musculus) Source

  5. Orphan designationPartial

    1 EMA designation (none yet with FDA orphan-indication approval) — e.g. recombinant adeno-associated viral vector serotype 2 carrying the gene for the human aromatic L-amino acid decarboxylase protein;Eladocagene exuparvovec Source

  6. Interventional trialPresent

    7 matched on ClinicalTrials.gov (2 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?

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

GenCC classification: Definitive.

Phenotypes (Monarch / HPO)

75

Associated phenotypes · MONDO:0012084

  • Hyperhidrosis
  • Seizure
  • Dystonia
  • Oculogyric crisis
  • Ptosis

Showing 5 of 75 — open Monarch for the full list.

Animal models (Monarch / Alliance)

1

Model associations linked to this Mondo ID

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)

1

Designation · no FDA orphan-indication approval yet

  • EMA recombinant adeno-associated viral vector serotype 2 carrying the gene for the human aromatic L-amino acid decarboxylase protein;Eladocagene exuparvovec (Upstaza)Treatment of aromatic L-amino acid decarboxylase deficiency · 18/11/2016 · PositiveEMA designation

Sources: FDA OOPD · EMA orphan designations

Open Targets candidates

1

Drugs / clinical candidates · MONDO_0012084

CTD chemicals (MyDisease.info)

No CTD chemical associations returned for this Mondo ID.

Literature

Is anyone studying this?

729

729 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.

729 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).

572 in the last 10 years · low confidence

Phrase hits: 702 · MeSH hits: 0

Open Europe PMC search

Who's working on it?

1,120

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.

  1. 01
    Hwu WL20 papers · 2025

    Department of Medical Genetics and Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, No. 8, Chung-Shan South Road, Taipei, 100226, Taiwan. hwuwlntu@ntu.edu.tw.

    Papers in Europe PMC
  2. 02
    Chien YH14 papers · 2026

    Department of Medical Genetics and Pediatrics, National Taiwan University Hospital, and College of Medicine, National Taiwan University, Taipei, Taiwan.

    Papers in Europe PMC
  3. 03
    Lee NC13 papers · 2025

    Department of Medical Genetics and Pediatrics, National Taiwan University Hospital, and College of Medicine, National Taiwan University, Taipei, Taiwan.

    Papers in Europe PMC
  4. 04
    Opladen T13 papers · 2026

    Department of Child Neurology and Metabolic Disorders, University Children's Hospital, Heidelberg, Germany.

    Papers in Europe PMC
  5. 05
    Bertoldi M10 papers · 2026

    Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy.

    Papers in Europe PMC
  6. 06
    Muramatsu SI9 papers · 2024

    Division of Neurological Gene Therapy, Jichi Medical University, Tochigi, Japan.

    Papers in Europe PMC
  7. 07
    Bisello G8 papers · 2026

    Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy.

    Papers in Europe PMC
  8. 08
    Kurian MA8 papers · 2025

    Developmental Neurosciences, Zayed Centre for Research, UCL GOS-ICH; Department of Neurology, Great Ormond Street Hospital, London, UK.

    Papers in Europe PMC
  9. 09
    Leuzzi V8 papers · 2026

    Department of Human Neuroscience, Sapienza - Università di Roma, Rome, Italy.

    Papers in Europe PMC
  10. 10
    Buesch K6 papers · 2022

    PTC Therapeutics, Zug 6300, Switzerland.

    Papers in Europe PMC

Clinical research

Is a treatment being tested?

7

interventional trials for this specific condition

7 interventional trials matched this specific condition name; 2 currently recruiting in our sample.

Data as of 11 September 2026 · last trial check 28 July 2026

7 interventional trials — more than 77.2% of diseases in the trials denominator have none at all (5501 of 7126; this disease is at the 90.9th percentile).

low confidence · 90.9th percentile (trials denominator)

Recruiting interventional trials

From the matched ClinicalTrials.gov set

7 interventional trials matched after quoted-phrase search and title/condition post-filter.

Observational and natural-history studies

2 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.

None of the matched observational studies is currently listed as recruiting.

Open the complete matched search on ClinicalTrials.gov

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 2026-07-29

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).

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 Aromatic L-amino acid decarboxylase deficiency — check Associations / patient organisations on that page.

India — NPRD

Last verified 2026-07-26

This 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.

("Aromatic L-amino acid decarboxylase deficiency" OR "AADC deficiency" OR "aromatic L-amino-acid decarboxylase deficiency") OR ("DDC syndrome" OR "DDC-related")

Run this search on Europe PMC

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

"Aromatic L-amino acid decarboxylase deficiency" OR "AADC deficiency" OR "aromatic L-amino-acid decarboxylase deficiency"

Interventional trials matched via: 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: 7 interventional · 2 observational · 0 expanded access. Only interventional studies enter the trial headline.

Query health: ok — strategies attempted: phrase; 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 (729) is implausibly high for prevalence class "<1 / 1 000 000" — treat as possible over-matching, not a measure of research intensity

Ingested 2026-07-26T23:48:47.253Z