A Safety and Efficacy Study Evaluating CTX001 in Participants With Transfusion-Dependent β-Thalassemia
← catalyst calendarSponsored by Vertex Pharmaceuticals Incorporated (industry) · VRTX — their whole pipeline →. With CRISPR Therapeutics.
Phase
Phase 2/3
Status
Completed
Study type
Interventional
Design
Na · None · Treatment
Enrollment
59actual
Sites
14
Countries
Canada, Germany, Italy +2
Every value on this page is a field the sponsor filed with ClinicalTrials.gov, reproduced. Dates are their own estimates, revised as a study runs, unless the registry marks them actual. sources →
Source: ClinicalTrials.gov, retrieved 2026-08-19
Dates
each axis at the precision it was filed, with the registry's own basis| Date | Filed | Basis | What it is |
|---|---|---|---|
| Start | 2018-09-14 | actual | When the study began enrolling |
| Primary completion | 2025-11-13 | actual | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2025-11-13 | actual | The whole study's end, after follow-up |
| First posted | 2018-08-31 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2025-12-17 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Conditions
- Beta-Thalassemia
- Thalassemia
- Genetic Diseases, Inborn
- Hematologic Diseases
- Hemoglobinopathies
Intervention
- Biological: CTX001 — also filed as Exagamglogene autotemcel, Exa-cel
Primary outcomes
what the primary-completion date above is the date OFProportion of participants achieving transfusion independence for at least 12 consecutive months (TI12)
measured From 60 days after last RBC transfusion up to 24 months post-CTX001 infusion]
Proportion of participants with engraftment (first day of 3 consecutive measurements of absolute neutrophil count [ANC] ≥500/µL on three different days)
measured Within 42 days after CTX001 infusion
Time to neutrophil and platelet engraftment
measured Days post-infusion to engraftment
Frequency and severity of collected adverse events (AEs)
measured Signing of informed consent through Month 24 visit
Incidence of transplant-related mortality (TRM)
measured Baseline (pre-transfusion) to 100 days and 1 year post-CTX001 infusion
All-cause mortality
measured Signing of informed consent through Month 24 visit
Publications
- PMID 42252696 — linked by the registry
- PMID 40862696 — linked by the registry
- PMID 38657265 — linked by the registry
- PMID 34175041 — linked by the registry
- PMID 33283989 — linked by the registry
Linked on the registry record. A “linked by the registry” entry is NLM's own automated PubMed match, not a claim by the sponsor that the paper reports this study.
Permalink · VRTX's whole pipeline · Catalyst calendar · Every registered study · What changed