Question

Which countries run stem-cell trials for Intellectual Disability?

Sampled registrations place sites in 12 countries. United States is the largest single contributor at roughly 38% of country mentions. Snapshot 2026-08-29.

Medical review statusMedically reviewedReviewed by: Stem Plus medical teamReviewed on: 2026-08-29Last evidence update: 2026-08-29Methodology and editorial standards
Clinical review team: Dr Kamelia Milcheva, Hematologist · Dr Vadym Uvarov, Board-Certified Physician · Hepatobiliary Surgeon · Candidate of Medical SciencesEditorial responsibility: StemCellAtlas research teamEducational information only. This page does not provide medical advice, diagnosis or a treatment recommendation.

Country distribution

CountryStudies with a site there
United States18
France6
United Kingdom5
Germany4
Italy4
Argentina3
Netherlands3
India2
Australia2
Canada1

A study with sites in several countries is counted once per country, taken from the location block of each registry record.

What the map means for Intellectual Disability

There is no coherent international trial geography for this umbrella category. Where studies exist they follow paediatric neurology and genetics infrastructure, and their eligibility is far narrower than the marketing that cites them.

Where recruitment is actually open

CountryOpen studies with a site there
United States2

What travelling for a trial actually involves

Travelling to a trial site is not like booking a treatment package. Sites enrol people they can follow up, which usually means repeated visits over months, local imaging or bloods, and an emergency route if something goes wrong. Ask about all three before booking anything.

Multi-country studies, named

Registered studies with sites in more than one country — the clearest evidence of collaboration rather than a single-centre series.

  • NCT02698579 — Long-term Follow-up of Participants With Cerebral Adrenoleukodystrophy Who Were Treated With Lenti-D Drug Product (Argentina, Australia, Brazil, France, Germany, Italy)
  • NCT03852498 — A Clinical Study to Assess the Efficacy and Safety of Gene Therapy for the Treatment of Cerebral Adrenoleukodystrophy (C (France, Germany, Italy, Netherlands, United Kingdom, United States)
  • NCT01896102 — A Study of the Efficacy and Safety of Hematopoietic Stem Cells Transduced With Lenti-D Lentiviral Vector for the Treatme (Argentina, Australia, France, Germany, United Kingdom, United States)

Why trial geography is not a shortlist

The map is drawn by policy and money. Permissive or well-defined regulatory pathways attract registrations and large research budgets attract more still. None of that transfers to the private clinic advertising in the same city, which may operate under no comparable supervision.

Before treating geography as a shortlist, read the legality overview by country and what "best country" actually means here.

When these studies started

Registrations by start year since 2020: 2020 (1), 2023 (1), 2026 (1). Activity for this condition spans 1995 to 2026, which shows whether interest is growing, flat or past its peak.

Frequently asked

Which countries run stem-cell trials for Intellectual Disability?

Sites are registered in 12 countries; the largest is United States (~38% of country mentions, 2026-08-29).

Does a country with many trials mean better treatment there?

No — trial counts describe where research is permitted and paid for. Care quality is decided at the level of the individual provider and product.

Are trial sites and commercial clinics the same thing?

Usually not. The hospital running a registered study is often unrelated to clinics marketing treatments to international patients in the same city.

Registry and literature counts retrieved 2026-08-29 (ClinicalTrials.gov API v2; PubMed E-utilities). Registration or publication volume measures research activity, not effectiveness or approval. Educational information — not medical advice; verify product, indication, legal pathway and evidence with an independent qualified physician. Page generated 2026-08-29. See our editorial standards.

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