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NCT03655678 · ClinicalTrials.gov registry record · Phase 2
A Safety and Efficacy Study Evaluating CTX001 in Participants With Transfusion-Dependent β-Thalassemia
A Phase 2 study, sponsored by Vertex Pharmaceuticals Incorporated.
- Completed
- Registry status
- Phase 2
- Development phase
- 59
- Enrollment target
NCT03655678: Completed Phase 2 study, sponsored by Vertex Pharmaceuticals Incorporated.
NCT03655678 is a Phase 2 study that has completed, run by Vertex Pharmaceuticals Incorporated. The registered enrollment target is 59 participants, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (56% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03655678, a Phase 2 study, has completed, sponsored by Vertex Pharmaceuticals Incorporated.
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 59 participants
- Enrollment target
Study Summary
This is a single-arm, open-label, multi-site, single-dose Phase 1/2/3 study in participans with transfusion-dependent β-thalassemia (TDT). The study will evaluate the safety and efficacy of autologous CRISPR-Cas9 Modified CD34+ Human Hematopoietic Stem and Progenitor Cells (hHSPCs) using CTX001.
Interventions
- BIOLOGICAL CTX001
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 59 participants |
| Start Date | 2018-09-14 |
| Est. Completion | 2025-11-13 |
| Phase | Phase 2 |
What the finished NCT03655678 record still lists
NCT03655678 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 59 participants, a relatively small participant target, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (56% lower).
The record links to 0 conditions, and to 1 intervention - of which CTX001 is the first listed.
NCT03655678 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT03655678 about?
NCT03655678 is a clinical study titled "A Safety and Efficacy Study Evaluating CTX001 in Participants With Transfusion-Dependent β-Thalassemia". This is a single-arm, open-label, multi-site, single-dose Phase 1/2/3 study in participans with transfusion-dependent β-thalassemia (TDT). The study will evaluate the safety and efficacy of autologous CRISPR-Cas9 Modified CD34+ Human Hematopoietic Stem and Progenitor Cells (hHSPCs) using CTX001.
What is the current status of trial NCT03655678?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 59 participants. The study started on 2018-09-14. Estimated completion is 2025-11-13.
What interventions are being tested in trial NCT03655678?
The interventions under investigation include: CTX001 (BIOLOGICAL).
Who is sponsoring clinical trial NCT03655678?
This trial is sponsored by Vertex Pharmaceuticals Incorporated, which has 191 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT03655678's enrollment target sits among peer trials
59 1133rd of 2000 higher than 866 of 2,000 other Phase 2 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 2 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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