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ORPHA:2309

Pachyonychia congenita

low confidenceDisorder

Also known as: PC

Publications

995

Trials

12

Interventional, condition-specific

Researchers

829

Distinct authors in sample

Gene link

—

Readiness

5/6

Stages with a signal

Clinical definition (Orphanet)

A rare genetic skin disease predominantly featuring painful palmoplantar keratoderma, thickened nails, cysts and white plaques affecting tongue and oral mucosa.

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.

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.”

5/6 stages with a signal

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

  1. Gene identifiedNot found

    No GenCC disease–gene assertion in this build

  2. LiteraturePresent

    995 matched papers (401 in last 10 years) Source

  3. Phenotype characterisedPresent

    61 HPO annotations (e.g. Palmoplantar keratoderma; Lower limb pain; Hyperplastic callus formation) Source

  4. Animal modelPresent

    2 genotype models (Mus musculus) Source

  5. Orphan designationPresent

    1 FDA · 4 EMA designations (1 FDA orphan-indication approval) — e.g. sirolimus Source

  6. Interventional trialPresent

    12 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?

Not yet — the cause hasn't been pinned down in GenCC.

No strong gene–disease assertion joined for this Orphanet entity.

Phenotypes (Monarch / HPO)

61

Associated phenotypes · MONDO:0016471

  • Palmoplantar keratoderma
  • Lower limb pain
  • Hyperplastic callus formation
  • Follicular hyperkeratosis
  • Feeding difficulties

Showing 5 of 61 — open Monarch for the full list.

Animal models (Monarch / Alliance)

2

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)

5

Designations · 1 with FDA orphan-indication approval

  • FDA sirolimusPachyonychia Congenita · 2013-03-18 · Not FDA Approved for Orphan Indication
  • EMA (R)-(3-(2'-cyclopropyl-3-(hydroxymethyl)-[1,1'-biphenyl]-4-yl) pyrrolidin-1-yl)(5-fluoropyridin-2-yl)methanoneTreatment of pachyonychia congenita · 28/06/2024 · PositiveEMA designation
  • EMA synthetic double-stranded siRNA oligonucleotide directed against the keratin 6a N171K mutationTreatment of pachyonychia congenita · 19/06/2013 · PositiveEMA designation
  • EMA erlotinibTreatment of pachyonychia congenita · 18/07/2022 · PositiveEMA designation
  • EMA sirolimusTreatment of pachyonychia congenita · 17/07/2017 · PositiveEMA designation

Sources: FDA OOPD · EMA orphan designations

Open Targets candidates

5

Drugs / clinical candidates · MONDO_0016471

CTD chemicals (MyDisease.info)

No CTD chemical associations returned for this Mondo ID.

Literature

Is anyone studying this?

995

995 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.

995 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).

401 in the last 10 years · low confidence

Phrase hits: 995 · MeSH hits: 0

Open Europe PMC search

Who's working on it?

829

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
    O'Toole EA15 papers · 2026

    Centre for Cell Biology and Cutaneous Research, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, U.K.

    Papers in Europe PMC
  2. 02
    Schwartz J15 papers · 2026

    Pachyonychia Congenita Project, Holladay, UT, USA.

    Papers in Europe PMC
  3. 03
    Sprecher E15 papers · 2026

    Department of Dermatology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.

    Papers in Europe PMC
  4. 04
    Hansen CD12 papers · 2025

    Department of Dermatology, University of Utah, Salt Lake City, Utah

    Papers in Europe PMC
  5. 05
    Smith FJD12 papers · 2021

    Dermatology and Genetic Medicine, Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, U.K.

    Papers in Europe PMC
  6. 06
    Coulombe PA10 papers · 2026

    Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA; Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, Michigan, USA; Department of Biological Chemistry, Johns Hopkins University, Baltimore, Maryland, USA; Department of Dermatology, Johns Hopkins University, Baltimore, Maryland, USA; Department of Oncology, School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA; Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, Maryland, USA. Electronic address: coulombe@umich.edu.

    Papers in Europe PMC
  7. 07
    Hovnanian A8 papers · 2026

    INSERM Unité Mixte de Recherche 1163, Laboratory of Genetic Skin Diseases, Imagine Institute, University of Paris, Paris, France; Université Paris Cité, Paris F-75015, France.

    Papers in Europe PMC
  8. 08
    Evans H7 papers · 2025

    Pachyonychia Congenita Project, Holladay, UT, USA.

    Papers in Europe PMC
  9. 09
    Samuelov L6 papers · 2022

    Division of Dermatology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.

    Papers in Europe PMC
  10. 10
    Schwartz ME6 papers · 2020

    PC Project, Salt Lake City, UT.

    Papers in Europe PMC

Clinical research

Is a treatment being tested?

12

interventional trials for this specific condition

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

Data as of 11 September 2026

12 interventional trials — more than 77.2% of diseases in the trials denominator have none at all (5501 of 7126; this disease is at the 93.2th percentile).

low confidence · 93.2th percentile (trials denominator)

Recruiting interventional trials

From the matched ClinicalTrials.gov set

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

Observational and natural-history studies

1 observational study matches 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.

Recruiting or not-yet-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 1 · after dedupe 1 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 1 · 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).

Uncertain / not reviewed (1)

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 Pachyonychia congenita — 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.

"Pachyonychia congenita"

Run this search on Europe PMC

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

"Pachyonychia congenita"

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: 12 interventional · 1 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

Synonyms dropped by stoplist: PC

Confidence reasoning

  • Preferred label is multi-word and distinctive
  • 1 synonym(s) dropped by stoplist (may under-count)
  • No label/synonym collisions with other diseases in this corpus
  • Publication count (995) is implausibly high for prevalence class "<1 / 1 000 000" — treat as possible over-matching, not a measure of research intensity

Ingested 2026-07-26T19:46:59.873Z