RARE DISEASERESEARCH ATLAS
Open navigation menu

ORPHA:158775

Smoldering systemic mastocytosis

high confidenceDisorder

Publications

357

72.3th percentile

Trials

4

Interventional, condition-specific

Researchers

1,344

Distinct authors in sample

Gene link

—

Readiness

2/6

Stages with a signal

Clinical definition (Orphanet)

A rare, slowly form of systemic mastocytosis (SM) characterized by gradual accumulation of neoplastic mast cells in the visceral organs. Patients typically present with , hypercellular marrow and, in most cases, urticaria pigmentosa-like skin lesions.

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.

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

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

    357 matched papers (257 in last 10 years) Source

  3. Phenotype characterisedNot found

    No HPO disease–phenotype associations via Monarch for these Mondo IDs

  4. Animal modelNot found

    No Alliance genotype “model of” associations via Monarch for these Mondo IDs

  5. Orphan designationNot found

    No FDA or EMA orphan-drug designation matched this disease via UMLS or preferred name Source

  6. Interventional trialPresent

    4 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?

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

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

Phenotypes (Monarch / HPO)

None returned for this Mondo ID. That often means “not linked under this ID,” not “no clinical features.”

Animal models (Monarch / Alliance)

None returned for this Mondo ID. Empty here is not proof that no model organism work exists under another name or gene.

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)

No designation matched this disease via UMLS or preferred name on the FDA OOPD mirror or EMA orphan register. Absence here is not proof that none exists under another wording.

Open Targets candidates

No drugs or clinical candidates returned for this Mondo ID on Open Targets.

CTD chemicals (MyDisease.info)

No CTD chemical associations returned for this Mondo ID.

Literature

Is anyone studying this?

357

357 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=3967) is 59.

357 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).

257 in the last 10 years · high confidence · 72.3th percentile (publications denominator)

Phrase hits: 357 · MeSH hits: 0

Open Europe PMC search

Who's working on it?

1,344

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
    Arock M9 papers · 2025

    CEREMAST Pitié-Salpêtrière, AP-HP, Paris, France.

    Papers in Europe PMC
  2. 02
    Hermine O9 papers · 2025

    French Reference Center for Mastocytosis (CEREMAST), ohermine@gmail.com.

    Papers in Europe PMC
  3. 03
    Niedoszytko M9 papers · 2025

    Department of Allergology, Medical University of Gdańsk, Gdańsk, Poland.

    Papers in Europe PMC
  4. 04
    Valent P9 papers · 2025

    Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Vienna, Austria. peter.valent@meduniwien.ac.at.

    Papers in Europe PMC
  5. 05
    Akin C8 papers · 2026

    Division of Allergy and Clinical Immunology, University of Michigan, Ann Arbor, MI, USA.

    Papers in Europe PMC
  6. 06
    Sperr WR7 papers · 2025

    Department of Internal Medicine I, Division of Hematology and Hemostaseology, Ludwig Boltzmann Institute for Hematology and Oncology, Medical University of Vienna, Vienna, Austria.

    Papers in Europe PMC
  7. 07
    Bonadonna P6 papers · 2025

    Multidisciplinary Mastocytosis Outpatient Clinic, Azienda Ospedaliera Universitaria Integrata of Verona

    Papers in Europe PMC
  8. 08
    Reiter A6 papers · 2025

    Hämatologie und Onkologie, III. Medizinische Klinik, Universitätsmedizin Mannheim, Universität Heidelberg, Mannheim, Germany.

    Papers in Europe PMC
  9. 09
    Siebenhaar F6 papers · 2026

    Institute of Allergology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.

    Papers in Europe PMC
  10. 10
    Triggiani M6 papers · 2025

    Division of Allergy and Clinical Immunology, University of Salerno, 84081 Baronissi, Italy.

    Papers in Europe PMC

Clinical research

Is a treatment being tested?

4

interventional trials for this specific condition

4 interventional trials matched this specific condition name; 1 currently recruiting in our sample. 33 trials are registered for systemic mastocytosis, the broader category — shown separately because they may or may not enrol this specific subtype.

Data as of 11 September 2026

4 interventional trials — more than 77.2% of diseases in the trials denominator have none at all (5501 of 7126; this disease is at the 88.1th percentile).

high confidence · 88.1th percentile (trials denominator)

Recruiting interventional trials

From the matched ClinicalTrials.gov set

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

Broader category: systemic mastocytosis

33

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

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.

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 2 · after dedupe 2 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 2 · dropped 0 · fetched 2026-07-30

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 (2)

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 Smoldering systemic mastocytosis — 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.

"Smoldering systemic mastocytosis"

Run this search on Europe PMC

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

"Smoldering systemic mastocytosis"

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

Parent-category trials query:

"systemic mastocytosis"

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 2026-07-27T08:08:04.294Z