RARE DISEASERESEARCH ATLAS
Open navigation menu

ORPHA:289326

Tropical spastic paraparesis

low confidenceDisorder

Also known as: HAM/TSP · HTLV-1-associated myelopathy/tropical spastic paraparesis · Human T-lymphotropic virus type I-associated myelopathy/tropical spastic paraparesis · Human T-lymphotropic virus type-1-associated myelopathy/tropical spastic paraparesis · TSP

Publications

4,535

Trials

10

Interventional, condition-specific

Researchers

1,012

Distinct authors in sample

Gene link

—

Readiness

4/6

Stages with a signal

Clinical definition (Orphanet)

Tropical spastic paraparesis is a chronic systemic immune-mediated inflammatory myeloneuropathy, more frequently reported in women than in men, that usually presents in adulthood with slowly spastic paraparesis of the lower limbs, bladder and bowel dysfunction, and sensory disturbances in the lower extremities (e.g. paresthesia and dysesthesia) and that is associated with a human T-cell lymphotropic virus type 1 (HTLV-1) infection.

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 (2)

ham/TSP · tropical spastic paraplegia

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.”

4/6 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

    4,535 matched papers (1,440 in last 10 years) Source

  3. Phenotype characterisedPresent

    5 HPO annotations (e.g. Spastic paraparesis; Myelopathy; Abnormal pyramidal sign) Source

  4. Animal modelPresent

    1 genotype model (Mus musculus) Source

  5. Orphan designationNot found

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

  6. 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)

5

Associated phenotypes · MONDO:0008039

  • Spastic paraparesis
  • Myelopathy
  • Abnormal pyramidal sign
  • Muscle weakness
  • Muscle stiffness

Animal models (Monarch / Alliance)

1

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)

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

10

Drugs / clinical candidates · MONDO_0008039

CTD chemicals (MyDisease.info)

3 associated chemicals. Therapeutic evidence is listed first when present — not a treatment recommendation.

  • Prednisone · therapeutic
  • Zidovudine · therapeutic
  • thiocyanate · marker/mechanism

MyDisease.info · MONDO:0008039

Literature

Is anyone studying this?

4,535

4,535 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.

4,535 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).

1,440 in the last 10 years · low confidence

Phrase hits: 4,535 · MeSH hits: 11

Open Europe PMC search

Who's working on it?

1,012

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
    Mozhgani SH21 papers · 2026

    Department of Microbiology, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran. hamidrezamozhgani@gmail.com.

    Papers in Europe PMC
  2. 02
    Kubota R11 papers · 2026

    Division of Neuroimmunology, Joint Research Center for Human Retrovirus Infection, Kagoshima University, Kagoshima City, Japan.

    Papers in Europe PMC
  3. 03
    Norouzi M11 papers · 2026

    Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran.

    Papers in Europe PMC
  4. 04
    Boostani R10 papers · 2026

    Department of Neurology, Mashhad University of Medical Sciences, Mashhad, Iran.

    Papers in Europe PMC
  5. 05
    Letafati A10 papers · 2026

    Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

    Papers in Europe PMC
  6. 06
    Matsuura E10 papers · 2026

    Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima City, Japan.

    Papers in Europe PMC
  7. 07
    Nozuma S10 papers · 2026

    Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima City, Japan.

    Papers in Europe PMC
  8. 08
    Takashima H10 papers · 2026

    Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima City, Japan.

    Papers in Europe PMC
  9. 09
    Tanaka M10 papers · 2026

    Division of Neuroimmunology, Joint Research Center for Human Retrovirus Infection, Kagoshima University, Kagoshima City, Japan.

    Papers in Europe PMC
  10. 10
    Casseb J9 papers · 2026

    Universidade de São Paulo, Faculdade de Medicina, Divisão de Dermatologia, Laboratório de Investigação Médica LIM-56, São Paulo, São Paulo, Brazil.

    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.

Data as of 11 September 2026

10 interventional trials — more than 77.2% of diseases in the trials denominator have none at all (5501 of 7126; this disease is at the 92.5th percentile).

low confidence · 92.5th 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.

Observational and natural-history studies

4 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

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 0 · after dedupe 0 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 0 · 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).

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 Tropical spastic paraparesis — 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.

"Tropical spastic paraparesis" OR "HAM/TSP" OR "HTLV-1-associated myelopathy/tropical spastic paraparesis" OR "Human T-lymphotropic virus type I-associated myelopathy/tropical spastic paraparesis" OR "Human T-lymphotropic virus type-1-associated myelopathy/tropical spastic paraparesis" OR "tropical spastic paraplegia"

Run this search on Europe PMC

MeSH descriptor terms unioned into the query: Paraparesis, Tropical Spastic

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

"Tropical spastic paraparesis" OR "HAM/TSP" OR "HTLV-1-associated myelopathy/tropical spastic paraparesis" OR "Human T-lymphotropic virus type I-associated myelopathy/tropical spastic paraparesis" OR "Human T-lymphotropic virus type-1-associated myelopathy/tropical spastic paraparesis" OR "tropical spastic paraplegia" OR "Paraparesis, Tropical Spastic"

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

Query health: ok — strategies attempted: phrase, mesh; with hits: phrase, mesh

Run this search on ClinicalTrials.gov

Synonyms dropped by stoplist: TSP

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 (4535) is extremely high with unknown/missing prevalence — treat as possible over-matching, not proven research intensity

Ingested 2026-07-27T12:11:38.748Z