What research stage is stem-cell therapy for Primary Immunodeficiency at?
The ladder for this condition: 7 Phase 3 or 4 records out of 93 registrations in total, snapshot 2026-08-29.
Phase distribution
| Phase label | Records | Share |
|---|---|---|
| Phase 2 | 55 | 45% |
| Phase 1 | 39 | 32% |
| Not applicable | 21 | 17% |
| Phase 3 | 6 | 5% |
| Phase 4 | 1 | 1% |
What the phase mix means for Primary Immunodeficiency
The phase profile mixes established transplant protocols with gene-therapy registrations, several of which have reached licensure. This is one of the few indications where later-phase counts correspond to approved products.
The later-phase studies themselves
| Study | Phase | Status | Planned n | Lead sponsor | Start |
|---|---|---|---|---|---|
| NCT04870333 — PROphylaxis for paTiEnts at Risk of COVID-19 infecTion -V | Phase 2, Phase 3 | Completed | 2,240 | Cambridge University Hospitals NHS Foundation Trust | 2021-02-19 |
| NCT02327351 — TCR Alpha/Beta Depletion for HSCT From Haploidentical and Unrelated Donors in the Treatment of PID | Phase 2, Phase 3 | Completed | 98 | Federal Research Institute of Pediatric Hematology, Oncology | 2012-07 |
| NCT06954441 — V-IMMUNE: A Novel Immunoglobulin Therapy for Immunodeficiency | Phase 3 | Recruiting | 50 | On Pharma Importadora, Exportadora e Distribuidora de Medica | 2025-08-15 |
| NCT01019876 — Risk-Adapted Allogeneic Stem Cell Transplantation For Mixed Donor Chimerism In Patients With Non-Malignant Diseases | Phase 2, Phase 3 | Completed | 38 | Columbia University | 2002-09 |
| NCT00176826 — T-Cell Depletion and Stem Cell Transplant for Immune Deficiencies and Histiocytic Disorders | Phase 2, Phase 3 | Terminated | 22 | Masonic Cancer Center, University of Minnesota | 2000-09 |
| NCT03837483 — A Clinical Study to Evaluate the Use of a Cryopreserved Formulation of OTL-103 in Subjects With Wiskott-Aldrich Syndrome | Phase 3 | Active Not Recruiting | 10 | Fondazione Telethon | 2019-01-21 |
How to read phase labels
Phase labels describe what a study was designed to answer. A Phase 1 result showing improvement answers a question nobody asked of it, because the design has no control arm and too few participants to distinguish an effect from noise.
Median planned enrolment across sampled studies here is 22 participants. Small single-arm studies can flag safety problems; they cannot separate a treatment effect from natural fluctuation, placebo response or regression to the mean.
The largest studies by planned enrolment
Size is a crude proxy for what a study can detect, but it separates a serious attempt from a case series presented as evidence.
| Study | Phase | Status | Planned n | Lead sponsor | Start |
|---|---|---|---|---|---|
| NCT04870333 — PROphylaxis for paTiEnts at Risk of COVID-19 infecTion -V | Phase 2, Phase 3 | Completed | 2,240 | Cambridge University Hospitals NHS Foundation Trust | 2021-02-19 |
| NCT01186913 — Natural History Study of SCID Disorders | n/a | Enrolling By Invitation | 690 | National Institute of Allergy and Infectious Diseases (NIAID | 2010-09-02 |
| NCT02064933 — Patients Treated for Wiskott-Aldrich Syndrome (WAS) Since 1990 | n/a | Completed | 305 | National Institute of Allergy and Infectious Diseases (NIAID | 2014-02-02 |
| NCT02065869 — Safety Study of Gene Modified Donor T-cells Following TCRαβ+ Depleted Stem Cell Transplant | Phase 1, Phase 2 | Terminated | 187 | Bellicum Pharmaceuticals | 2014-04 |
| NCT00110045 — Caspofungin Acetate in Treating Aspergillosis in Patients With Hematologic Cancer or in Patients Who Have Undergone a Stem Cell Transplant | Phase 2 | Completed | 171 | European Organisation for Research and Treatment of Cancer - | 2005-02 |
Frequently asked
What research stage is stem-cell therapy for Primary Immunodeficiency at?
7 of 93 records are labelled Phase 3 or 4 (2026-08-29).
Is a Phase 3 trial proof that it works?
No — it is a design capable of testing that question. Proof depends on the reported result, replication, and whether the outcome measured matters to patients.
Why do so many records have no phase?
Observational studies and some cell-therapy protocols are registered without a phase label. It is a registry field, not a quality rating.
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.