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Protein / target

Aromatic-L-amino-acid decarboxylase

Encoded byDDCP20711Homo sapiensSwiss-Prot
Clinically validated
Therapeutic maturity
2
Approved medicines
Open Targets target-level
View by indication →
30
Clinical trials
Small-molecule tractable
Druggability
Approved Drug

Protein at a glance

Biological role

5-hydroxy-L-tryptophan decarboxylase

Strongest disease association

aromatic L-amino acid decarboxylase deficiency

Via encoding gene DDC · Genetic evidence · score 0.92

Therapeutic position

Established drug target

Small molecules

Research activity

Emerging research

1 papers · latest 2023

Derived from structured UniProt, Open Targets and literature data on this page.

Protein profile

UniProt 2026_02

Canonical identity and biological annotation from UniProt.

Function overview

Catalyzes the decarboxylation of L-3,4-dihydroxyphenylalanine (DOPA) to dopamine and L-5-hydroxytryptophan to serotonin

Domains and Gene Ontology detail (13)

Gene Ontology

  • Ccytoplasm
  • Ccytosol
  • Cextracellular exosome
  • F5-hydroxy-L-tryptophan decarboxylase activity
  • Faromatic-L-amino-acid decarboxylase activity
  • Fenzyme binding
  • FL-dopa decarboxylase activity
  • Fpyridoxal phosphate binding
  • Pamino acid metabolic process
  • Pcarboxylic acid metabolic process
  • Pcatecholamine metabolic process
  • Pdopamine biosynthetic process

480 aa · 54 kDa · 4 isoforms

Biological roles

Reactome v97

What this protein does, drawn together from its UniProt function, Gene Ontology terms and Reactome pathways.

Metabolic enzyme activityGO
View supporting evidence

Metabolic enzyme activity

  • ·amino acid metabolic process
  • ·carboxylic acid metabolic process
  • ·catecholamine metabolic process
View underlying pathways (2)

Concepts derived from UniProt GO Reactome — each badge above shows which sources supported that role.

Interaction neighbourhood

STRING v12.0

Proteins with the strongest functional or physical association. Node size and line weight reflect STRING confidence; hover or select a partner to inspect one association.

THMAOBMAOADBHPAHCOMTTPH1LRTOMTTPH2AOC1DDC

10 strongest partners — larger node and heavier line mean higher confidence

Functional and physical associations from STRING v12.0. Only associations with this protein are drawn — partner-to-partner links are not part of this evidence.

Approved medicines with mapped indications

1 medicine · 2 areas

Approved therapies targeting this protein, grouped by what they are approved to treat — the disease-first view of the medicines below. Relationships come from the canonical approved-indication graph (ChEMBL phase-4), the same source as the drug cards.

Parkinson's Disease1 medicine
Wounds and Injuries1 medicine

2 medicines meet Open Targets' target-level approved-medicine definition; the 1 shown here are those on this page with a canonical approved disease indication in the graph. Approved indications from ChEMBL (phase-4), via the canonical drug→disease graph.

Drugs targeting this protein

1

How approved and investigational drugs engage this protein — mechanism and action type, direct vs complex targeting, and how broadly each acts across other targets. A drug-first view (the section above groups the approved ones disease-first); direct binders with few recorded targets are listed first.

Carbidopa
Narrow target profileApprovedInhibitor

DOPA decarboxylase inhibitor

Indicated for Parkinson's Disease, Wounds and Injuries

Direct interaction with this protein · Only this protein recorded as a target

ChEMBL mechanism, action type, target identity and approved indications. Open Targets clinical status.

Translational evidence

Open Targets 26

Why this target matters therapeutically, strongest evidence first. Disease associations are gene-level (via the gene that encodes this protein) and open into the full confidence synthesis; the development universe, tractability and safety annotations are target-level, from Open Targets.

Strongest disease associations · via encoding gene DDC

Gene-level evidence surfaced through the gene DDC that encodes this protein — not a direct protein–disease relationship. Ranked by Forefront's causal-directness weighting, so genetically- and clinically-evidenced diseases lead over ones that merely share the literature.

aromatic L-amino acid decarboxylase deficiency
0.94Well supported

Genetic evidence dominant · Open Targets 0.84

Genetic Diseases, Inborn
0.83Well supported

Genetic evidence dominant · Open Targets 0.51

Parkinson's Disease
0.79Well supported

Clinical evidence dominant · Open Targets 0.62

postencephalitic Parkinson's disease
0.53Moderately supported

Clinical evidence dominant · Open Targets 0.38

Oculogyric crisis
0.49Limited support

Genetic literature evidence dominant · Open Targets 0.37

View evidence synthesis (5)
aromatic L-amino acid decarboxylase deficiencyWell supported
0.94
agreement 0.841.00
Genetic79%Animal model10%Clinical10%Literature1%Genetic literaturedup

Open Targets aggregate 0.84 · 4 independent evidence families · 1 not counted as duplicate

Genetic Diseases, InbornWell supported
0.83
agreement 0.690.97
Genetic98%Literature2%

Open Targets aggregate 0.51 · 2 independent evidence families

Parkinson's DiseaseWell supported
0.79
agreement 0.680.91
Clinical80%Animal model12%Literature7%RNA expression1%

Open Targets aggregate 0.62 · 4 independent evidence families

postencephalitic Parkinson's diseaseModerately supported
0.53
agreement 0.390.67
Clinical78%Animal model22%

Open Targets aggregate 0.38 · 2 independent evidence families

Oculogyric crisisLimited support
0.49
agreement 0.340.64
Genetic literature99%Literature1%

Open Targets aggregate 0.37 · 2 independent evidence families

The evidence agreement range shows how closely the independent evidence families agree — it is not a statistical confidence interval, and nothing here is fitted to outcome data. Derived from Open Targets evidence types under Forefront weighting; the per-type scores above show the calculation.

Show all associations
aromatic L-amino acid decarboxylase deficiency0.84
Parkinson's Disease0.62
Genetic Diseases, Inborn0.51
postencephalitic Parkinson's disease0.38
Oculogyric crisis0.37

Drug development

4 compounds recorded · 2 approved · 2 in clinical development

Open Targets' development universe — every compound recorded against the target at any stage, not all approved medicines. Distinct from the 1 drug that targets this protein in Forefront's canonical graph (1 with a mapped approved indication, shown above): these count different sets and are not a subset relation.

View all recorded compounds (4)
CARBIDOPAApproval
ELADOCAGENE EXUPARVOVECApproval
FOSCARBIDOPAPhase 3
BENSERAZIDEPhase 3

Open Targets known-drugs universe. Drug name and highest clinical stage only — the disease relationship is NOT read from this slice (it carries trial-context noise); approved indications come from the canonical graph above.

Tractability

Small moleculesStrong

Approved Drug and Structure with Ligand support this modality.

View underlying tractability evidence (4)
SM · Approved DrugSM · Structure with LigandSM · High-Quality PocketSM · Druggable Family

Raw Open Targets tractability assessment buckets, by modality.

Safety-related annotations

addictionClinPGx

Terms indexed against this target in Open Targets' safety data, with their datasource. These are annotations, not causal claims: the direction of effect (whether activation or inhibition is implicated), species and evidence strength are not captured here, so an entry does not mean that modulating this target is known to cause that condition.

Clinical trials

30

Trials of drugs that target this protein — reached indirectly through those drugs, so a trial listed here studies the drug, not the protein. Ranked by active status, then clinical phase and recency, and spread across the targeting drugs.

View all trials (26)

COMPLETED · via Carbidopa · NCT06587217

COMPLETED · via Carbidopa · NCT06219915

WITHDRAWN · via Carbidopa · NCT04764383

COMPLETED · via Carbidopa · NCT04325503

COMPLETED · via Carbidopa · NCT03929068

ClinicalTrials.gov via the drug-target graph.

What's happening now

12

Recent therapeutic activity around this target — regulatory actions, clinical trials and safety signals for a drug that targets this protein, plus publications where such a drug is a genuine subject. Every item is reached indirectly through the drug, not the protein itself; incidental mentions (a paper that merely measures a drug) and press items are excluded.

  1. Label change2026-09-11

    Label change: CARBIDOPA AND LEVODOPA (ANDA074260)

    fda · regulatory · fda · via Carbidopa

  2. Label change2026-09-11

    Label change: CARBIDOPA AND LEVODOPA (ANDA078536)

    fda · regulatory · fda · via Carbidopa

  3. Label change2026-05-15

    Label change: CARBIDOPA AND LEVODOPA (NDA217186)

    fda · regulatory · fda · via Carbidopa

  4. Label change2026-03-19

    Label change: CARBIDOPA AND LEVODOPA (NDA217186)

    fda · regulatory · fda · via Carbidopa

  5. Regulatory approval2024-08-07

    Approval: CARBIDOPA AND LEVODOPA (NDA217186)

    fda · regulatory · fda · via Carbidopa

  6. Supplemental approval2014-11-04

    Supplemental approval: CARBIDOPA AND LEVODOPA (ANDA074260)

    fda · regulatory · fda · via Carbidopa

  7. Regulatory approval2008-10-28

    Approval: CARBIDOPA AND LEVODOPA (ANDA078536)

    fda · regulatory · fda · via Carbidopa

  8. Supplemental approval2007-06-19

    Supplemental approval: CARBIDOPA AND LEVODOPA (ANDA074260)

    fda · regulatory · fda · via Carbidopa

  9. New publication2004-12-01
    Levodopa and the progression of Parkinson's disease.

    The New England journal of medicine · 2004 · 1,175 citations · Europe PMC · via Carbidopa

  10. Supplemental approval1996-01-18

    Supplemental approval: CARBIDOPA AND LEVODOPA (ANDA074260)

    fda · regulatory · fda · via Carbidopa

  11. Supplemental approval1995-11-21

    Supplemental approval: CARBIDOPA AND LEVODOPA (ANDA074260)

    fda · regulatory · fda · via Carbidopa

  12. Regulatory approval1993-09-03

    Approval: CARBIDOPA AND LEVODOPA (ANDA074260)

    fda · regulatory · fda · via Carbidopa

Objective event titles are shown unmodified; the event kind and significance line are derived from structured fields. Forefront AttentionEvent stream aggregating Europe PMC Regulatory filings ClinicalTrials.gov.

Research activity

1 papers · to 2023

Papers linked directly to this protein. This is the protein's own literature — descriptor-derived papers are kept separate below.

Most cited

Recent

Europe PMC papers linked directly to this protein.