ORPHA:98848
Indolent systemic mastocytosis
Publications
692
89.6th percentile
Trials
10
Interventional, condition-specific
Researchers
1,083
Distinct authors in sample
Gene link
—
Readiness
2/6
Stages with a signal
Clinical definition (Orphanet)
A rare, usually benign, chronic, form of systemic mastocytosis (SM) characterized by an abnormal accumulation of neoplastic mast cells (MCs) mainly in the bone marrow (BM) but also in other organs or tissues such as preferably the skin.
How rare: 1-5 / 10 000 — about one to five people per ten thousand (still uncommon, but less ultra-rare).
Cross-references
Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.
- MONDO:0020331
- UMLS:C0272203
- NCIT:C9286
Additional Mondo synonyms (3)
ISM · indolent systemic mastocytosis (morphologic abnormality) · ism
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.
- Gene identifiedNot found
No GenCC disease–gene assertion in this build
- LiteraturePresent
692 matched papers (465 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
10 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)
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?
692
692 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=5449) is 41.
692 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).
465 in the last 10 years · medium confidence · 89.6th percentile (publications denominator)
Phrase hits: 692 · MeSH hits: 0
Who's working on it?
1,083
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.
- 01Akin C20 papers · 2026
Department of Internal Medicine, Allergy Immunology, University of Michigan, Ann Arbor, Mich. Electronic address: cemakin@med.umich.edu.
Papers in Europe PMC - 02Reiter A14 papers · 2026
Department of Hematology and Oncology, University Hospital Mannheim, Heidelberg University, Mannheim, Germany.
Papers in Europe PMC - 03Castells M13 papers · 2026
Division of Allergy and Clinical Immunology, Brigham and Women's Hospital, Boston, Mass; Harvard Medical School, Boston, Mass. Electronic address: mcastells@bwh.harvard.edu.
Papers in Europe PMC - 04Hartmann K13 papers · 2026
Department of Dermatology, University of Cologne, Cologne, Germany; Division of Allergy, Department of Dermatology, and Department of Biomedicine, University of Basel, Basel, Switzerland.
Papers in Europe PMC - 05Valent P13 papers · 2025
Department of Internal Medicine I, Division of Hematology and Hemostaseology, and Ludwig Boltzmann Institute for Hematology and Oncology, Medical University of Vienna, Vienna, Austria.
Papers in Europe PMC - 06Niedoszytko M12 papers · 2025
Department of Allergology, Medical University of Gdańsk, Gdańsk, Poland.
Papers in Europe PMC - 07Sabato V12 papers · 2026
Faculty of Medicine and Health Sciences, Department of Immunology-Allergology-Rheumatology, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium.
Papers in Europe PMC - 08Siebenhaar F12 papers · 2026
Dermatological Allergology, Department of Dermatology and Allergy, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.
Papers in Europe PMC - 09George TI11 papers · 2026
Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA.
Papers in Europe PMC - 10Bonadonna P10 papers · 2026
Allergy Unit, Verona University Hospital, Verona, Italy.
Papers in Europe PMC
Clinical research
Is a treatment being tested?
10
interventional trials for this specific condition
10 interventional trials matched this specific condition name; 1 currently recruiting in our sample. 27 trials are registered for systemic mastocytosis, the broader category — shown separately because they may or may not enrol this specific subtype.
Data as of 27 July 2026
10 interventional trials — more than 73% of diseases in the trials denominator have none at all (5114 of 7003; this disease is at the 91.7th percentile).
medium confidence · 91.7th percentile (trials denominator)
Recruiting interventional trials
From the matched ClinicalTrials.gov set
10 interventional trials matched after quoted-phrase search and title/condition post-filter.
- NCT04910685·RECRUITING·(HARBOR) Study to Evaluate Efficacy and Safety of BLU-263 Versus Placebo in Patients With Indolent Systemic Mastocytosis
Conditions: Indolent Systemic Mastocytosis · Smoldering Systemic Mastocytosis·Matched via name phrase
Broader category: systemic mastocytosis
27
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
- NCT04996875·RECRUITING·(Apex) Bezuclastinib in Patients With Advanced Systemic Mastocytosis
Conditions: Advanced Systemic Mastocytosis (AdvSM) · SM With an Associated Hematologic Neoplasm (SM-AHN) · Mast Cell Leukemia (MCL) · Aggressive Systemic Mastocytosis (ASM)·Matched via name phrase
- NCT06327685·RECRUITING·Avapritinib With Decitabine in Patients With SM-AHN
Conditions: Systemic Mastocytosis With an Associated Hematologic Neoplasm·Matched via name phrase
Observational and natural-history studies
6 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.
Recruiting or not-yet-recruiting
- NCT07264959·RECRUITING·An Observational Study in Participants With Indolent Systemic Mastocytosis (ISM)
Conditions: Indolent Systemic Mastocytosis·Matched via name phrase
- NCT07255638·RECRUITING·A Non-Interventional Study in Participants With Indolent Systemic Mastocytosis (ISM) in Germany
Conditions: Indolent Systemic Mastocytosis·Matched via name phrase
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 2026-07-26This 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.
"Indolent systemic mastocytosis" OR "indolent systemic mastocytosis (morphologic abnormality)"
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Indolent systemic mastocytosis" OR "indolent systemic mastocytosis (morphologic abnormality)"
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: 10 interventional · 6 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
Synonyms dropped by stoplist: ISM
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
Ingested 2026-07-27T05:35:00.480Z
