ORPHA:79096

Pyridoxamine-5-phosphate deficiency-developmental and epileptic encephalopathy

high confidenceDisorder

Also known as: P5PD-DEE · PNPO-related neonatal epileptic encephalopathy · Pyridoxal phosphate-dependent seizures · Pyridoxal phosphate-responsive seizures · Pyridoxamine 5'-phosphate oxidase deficiency

Query health: suspect — Only one of 3 strategies returned hits (phrase).

Publications

292

79.6th percentile

Trials

Interventional, condition-specific

Researchers

1,181

Distinct authors in sample

Gene link

PNPO

Definitive

Readiness

3/6

Stages with a signal

Clinical definition (Orphanet)

A very rare epileptic disorder characterized clinically by onset of severe within hours of birth that are not responsive to anticonvulsants, but are responsive to treatment with pyridoxal phosphate.

How rare: How common this is has not been clearly measured.

Orphanet entry

Cross-references

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

Additional Mondo synonyms (5)

PNPO deficiency · pyridox(am)ine 5’-phosphate oxidase deficiency · pyridoxal phosphate-dependent seizures · pyridoxamine 5'-phosphate oxidase deficiency · pyridoxine 5' phosphate oxidase 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.”

3/6 stages with a signal

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

Gene identifiedPresent
Definitive — PNPO
LiteraturePresent
292 matched papers (212 in last 10 years) Source
Phenotype characterisedNot checked
Not yet enriched from Monarch / HPO
Animal modelNot checked
Not yet enriched from Monarch / Alliance
Orphan designationNot checked
FDA/EMA orphan-drug designation not enriched yet
Interventional trialPresent
1 matched on ClinicalTrials.gov (1 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 (PNPO).

GenCC classification: Definitive.

PNPO

Phenotypes (Monarch / HPO)

Not enriched in this build — Monarch phenotype joins were not run for this record.

Animal models (Monarch / Alliance)

Not enriched in this build.

Literature

Is anyone studying this?

292

292 papers have ever been published on this condition (under this name). For scale, breast cancer has over 700,000. Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=5449) is 41.

292 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 41 (publications denominator n=5449).

212 in the last 10 years · high confidence · 79.6th percentile (publications denominator)

Phrase hits: 292 · MeSH hits: 0

Open Europe PMC search

Who's working on it?

1,181

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.

01
Clayton PT11 papers · 2026
Centre for Translational Omics, Genetics and Genomic Medicine, UCL Institute of Child Health, 30 Guilford Street, London, UK, WC1N 1EH. peter.clayton@ucl.ac.uk.
Papers in Europe PMC
02
Plecko B11 papers · 2025
From the Department of Pediatrics (B.P., L.A.), Division of Child Neurology, University Hospital Zurich, Switzerland; the Department of Pediatrics (B.P.), Division of Neurology and Inborn Errors of Metabolism, Medical University Graz, Austria; radiz-"Rare Disease Initiative Zurich, Clinical Research Priority Program for Rare Diseases University of Zurich" (B.P., L.A.); CRC Clinical Research Center (B.P.), University Childrens' Hospital Zurich, Switzerland; the Laboratory of Metabolic Diseases (K.P., E.P., D.H.), Department of Pediatrics, University Hospital Graz, Austria; UCL Institute of Child Health (P.M., P.C.), Clinical and Molecular Genetics Unit, London, UK; Childrens Hospital St. Gallen (O.M., O.H.), Switzerland; the Department of Pediatrics (G.H.), Klinikum Esslingen; the Department of Pediatrics (S.K.), St. Marien Hospital, Landshut, Germany; the Division of Child Neurology (M.C.) and Division of Biochemical Diseases (S.S.), Department of Pediatrics, University of British Columbia, Vancouver, Canada; the Department of Pediatrics, Division of Child Neurology (N.W.), VU University Medical Center and Neuroscience Campus Amsterdam; and the Department of Clinical Chemistry (E.S.), Vrije Universiteit Amsterdam, the Netherlands.
Papers in Europe PMC
03
Zhuang X10 papers · 2026
Department of Neurobiology, University of Chicago, Chicago, Illinois 60637 xzhuang@bsd.uchicago.edu.
Papers in Europe PMC
04
Chi W9 papers · 2026
The Ken & Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA. wanhao.chi@northwestern.edu.
Papers in Europe PMC
05
Clayton P9 papers · 2026
UCL Institute of Child Health, London, UK.
Papers in Europe PMC
06
Mills PB9 papers · 2026
Centre for Translational Omics, Genetics and Genomic Medicine, UCL Institute of Child Health, 30 Guilford Street, London, UK, WC1N 1EH.
Papers in Europe PMC
07
van Karnebeek CDM7 papers · 2024
Department of Pediatrics, Amsterdam UMC, Amsterdam, The Netherlands. clara.vankarnebeek@radboudumc.nl.
Papers in Europe PMC
08
Contestabile R6 papers · 2024
Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Sapienza Università di Roma, Italy.
Papers in Europe PMC
09
di Salvo ML6 papers · 2024
Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Sapienza Università di Roma, Italy.
Papers in Europe PMC
10
Fu W6 papers · 2026
Department of Neurobiology, University of Chicago, Chicago, IL 60637.
Papers in Europe PMC

Clinical research

Is a treatment being tested?

interventional trials for this specific condition

1 interventional trial matched this specific condition name; 1 currently recruiting in our sample.

Data as of 27 July 2026

1 interventional trial — more than 73% of diseases in the trials denominator have none at all (5114 of 7003; this disease is at the 76.8th percentile).

high confidence · 76.8th percentile (trials denominator)

Recruiting interventional trials

From the matched ClinicalTrials.gov set

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

NCT04706013·RECRUITING·Oral Pyridoxal 5'-Phosphate for the Treatment of Patients With PNPO Deficiency
Conditions: Pyridox(am)Ine 5'-Phosphate Oxidase Deficiency·Matched via name phrase

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

Where to find support

We do not yet link condition-specific patient organisations. These umbrella groups support undiagnosed and ultra-rare families:

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.

"Pyridoxamine-5-phosphate deficiency-developmental and epileptic encephalopathy" OR "P5PD-DEE" OR "PNPO-related neonatal epileptic encephalopathy" OR "Pyridoxal phosphate-dependent seizures" OR "Pyridoxal phosphate-responsive seizures" OR "Pyridoxamine 5'-phosphate oxidase deficiency" OR "PNPO deficiency" OR "pyridox(am)ine 5’-phosphate oxidase deficiency" OR "pyridoxine 5' phosphate oxidase deficiency"

Run this search on Europe PMC

MeSH descriptor terms unioned into the query: Pyridoxamine 5-Prime-Phosphate Oxidase Deficiency

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

"Pyridoxamine-5-phosphate deficiency-developmental and epileptic encephalopathy" OR "P5PD-DEE" OR "PNPO-related neonatal epileptic encephalopathy" OR "Pyridoxal phosphate-dependent seizures" OR "Pyridoxal phosphate-responsive seizures" OR "Pyridoxamine 5'-phosphate oxidase deficiency" OR "PNPO deficiency" OR "pyridox(am)ine 5’-phosphate oxidase deficiency" OR "pyridoxine 5' phosphate oxidase deficiency" OR "Pyridoxamine 5-Prime-Phosphate Oxidase Deficiency" OR "PNPO"

Recall-expansion terms: PNPO

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: 1 interventional · 2 observational · 0 expanded access. Only interventional studies enter the trial headline.

Query health: suspect — strategies attempted: phrase, mesh, recall-expansion; 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

Ingested 2026-07-27T01:56:13.871Z