RARE DISEASERESEARCH ATLAS
Open navigation menu

ORPHA:293284

Tetrahydrobiopterin-responsive phenylketonuria

high confidenceSubtype of disorder

Also known as: BH4-responsive PKU · BH4-responsive phenylketonuria · Tetrahydrobiopterin-responsive PKU

Publications

127

62.1th percentile

Trials

0

Interventional, condition-specific

Researchers

696

Distinct authors in sample

Gene link

—

Readiness

2/6

Stages with a signal

Clinical definition (Orphanet)

A form of phenylketonuria (PKU), an inborn error of amino acid metabolism, characterized by mild to moderate symptoms of PKU including impaired cognitive function, , and behavioral and developmental disorders, and a marked reduction of elevated phenylalanine concentrations after oral loading with tetrahydrobiopterin (BH4), an essential cofactor of phenylalanine hydroxylase.

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 (3)

BH4-responsive HPA/PKU · BH4-responsive hyperphenylalaninemia/phenylketonuria · tetrahydrobiopterin-responsive HPA/PKU

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.”

2/6 stages with a signal

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

  1. Gene identifiedNot found

    No GenCC disease–gene assertion in this build

  2. LiteraturePresent

    127 matched papers (78 in last 10 years) Source

  3. Phenotype characterisedNot checked

    Not yet enriched from Monarch / HPO

  4. Animal modelNot checked

    Not yet enriched from Monarch / Alliance

  5. Orphan designationNot checked

    FDA/EMA orphan-drug designation not enriched yet

  6. Interventional trialPartial

    None under the specific name; 92 for broader category phenylketonuria

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)

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?

127

127 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.

127 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).

78 in the last 10 years · high confidence · 62.1th percentile (publications denominator)

Phrase hits: 127 · MeSH hits: 0

Open Europe PMC search

Who's working on it?

696

Distinct author names in 127 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
    Blau N9 papers · 2021

    University Children's Hospital, Dietmar-Hoppe Metabolic Centre, Heidelberg, Germany.

    Papers in Europe PMC
  2. 02
    Martinez A9 papers · 2021

    Department of Biomedicine and K.G. Jebsen Centre for Neuropsychiatric Disorders, University of Bergen, Bergen 5009, Norway.

    Papers in Europe PMC
  3. 03
    Muntau AC8 papers · 2021

    University Children's Hospital, University Medical Centre Hamburg-Eppendorf, 20246, Hamburg, Germany.

    Papers in Europe PMC
  4. 04
    van Spronsen FJ8 papers · 2021

    Division of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, PO BOX 30.001, 9700 RB, Groningen, The Netherlands. f.j.van.spronsen@umcg.nl.

    Papers in Europe PMC
  5. 05
    Burlina A7 papers · 2021

    Division of Inherited Metabolic Diseases, Department of Paediatrics, University Hospital of Padova, Padova, Italy.

    Papers in Europe PMC
  6. 06
    Feillet F5 papers · 2023

    Department of Paediatrics, Hôpital d'Enfants Brabois, CHU Nancy, Vandoeuvre les Nancy, France.

    Papers in Europe PMC
  7. 07
    Leuzzi V5 papers · 2021

    Department of Paediatrics, Child Neurology and Psychiatry, Sapienza University of Rome, Via dei Sabelli 108, 00185, Rome, Italy.

    Papers in Europe PMC
  8. 08
    Thöny B5 papers · 2018

    Division of Metabolism, Clinical Chemistry and Biochemistry, Division of Metabolism, Department of Pediatrics, University of Zürich, Zürich 8032, Switzerland.

    Papers in Europe PMC
  9. 09
    Bosch AM4 papers · 2021

    Department of Paediatrics, Division of Metabolic Disorders, Academic Medical Centre, University Hospital of Amsterdam, Amsterdam, The Netherlands.

    Papers in Europe PMC
  10. 10
    Heiner-Fokkema MR4 papers · 2021

    Division of Metabolic Diseases, University Medical Center Groningen, Beatrix Children’s Hospital CA33, PO box 30.001, Groningen 9700 RB, The Netherlands

    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). 92 trials are registered for phenylketonuria, the broader category — shown separately because they may or may not enrol this specific subtype.

Data as of 27 July 2026

No matched interventional trials. This is true for 73% of diseases in the trials denominator (5114 of 7003). Here are the researchers publishing on it.

high confidence · 36.5th 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.

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

Broader category: phenylketonuria

92

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

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

Likely covered — the policy lists Phenylketonuria (PKU) 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 College — New Delhi, Delhi
  • Sanjay Gandhi Post Graduate Institute of Medical Sciences — Lucknow, Uttar Pradesh
  • Post Graduate Institute of Medical Education and Research (PGIMER) — Chandigarh, Chandigarh
  • Centre for DNA Fingerprinting & Diagnostics with Nizam’s Institute of Medical Sciences — Hyderabad, Telangana
  • King Edward Memorial Hospital — Mumbai, Maharashtra
  • Institute of Post-Graduate Medical Education and Research (IPGMER) — Kolkata, West Bengal
  • Centre for Human Genetics with Indira Gandhi Hospital — Bengaluru, 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 College — Thiruvananthapuram, 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 & Hospital — Dibrugarh, 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.

"Tetrahydrobiopterin-responsive phenylketonuria" OR "BH4-responsive PKU" OR "BH4-responsive phenylketonuria" OR "Tetrahydrobiopterin-responsive PKU" OR "BH4-responsive HPA/PKU" OR "BH4-responsive hyperphenylalaninemia/phenylketonuria" OR "tetrahydrobiopterin-responsive HPA/PKU"

Run this search on Europe PMC

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

"Tetrahydrobiopterin-responsive phenylketonuria" OR "BH4-responsive PKU" OR "BH4-responsive phenylketonuria" OR "Tetrahydrobiopterin-responsive PKU" OR "BH4-responsive HPA/PKU" OR "BH4-responsive hyperphenylalaninemia/phenylketonuria" OR "tetrahydrobiopterin-responsive HPA/PKU"

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

Parent-category trials query:

"phenylketonuria"

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

Ingested 2026-07-27T12:20:45.958Z