Recruiting
Phase 3

CTX001

Sponsor:

Vertex Pharmaceuticals Incorporated

Code:

NCT05477563

Conditions

Beta-Thalassemia

Thalassemia

Hematologic Diseases

Genetic Diseases, Inborn

Hemoglobinopathies

Eligibility Criteria

Sex: All

Age: 12 - 35

Healthy Volunteers: Not accepted

Interventions

CTX001

Study Details

Brief summary:

This is a single-dose, open-label study in participants with transfusion-dependent β-thalassemia (TDT) or severe sickle cell disease (SCD). The study will evaluate the safety and efficacy of autologous CRISPR-Cas9 modified CD34+ human hematopoietic stem and progenitor cells (hHSPCs) using CTX001.

Conditions

Beta-Thalassemia

Thalassemia

Hematologic Diseases

Genetic Diseases, Inborn

Hemoglobinopathies

Study ID

NCT05477563

Start date

Aug 2, 2022

Status verified date

Mar, 2026

Completion date

Jun 9, 2027

Anticipated

Primary completion date

Jun 9, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 12 - 35

Healthy Volunteers: Not accepted

Key Inclusion Criteria:

  • Participants with TDT and SCD:
  • Eligible for autologous stem cell transplant as per investigator's judgment.
  • Participants with TDT:
  • Diagnosis of TDT as defined by:
  • Documented homozygous β-thalassemia or compound heterozygous β-thalassemia including β-thalassemia/hemoglobin E (HbE). Participants can be enrolled based on historical data, but a confirmation of the genotype using the study central laboratory will be required before busulfan conditioning
  • History of at least 100 milliliter (mL)/kilograms (kg)/year or 10 units/year of packed red blood cells (RBC) transfusions in the prior 2 years before signing the consent or the last rescreening for patients going through re-screening
  • Participants with SCD:
  • Diagnosis of severe SCD as defined by:
  • Documented SCD genotypes
  • History of at least two severe VOCs events per year for the previous two years prior to enrollment

Key Exclusion Criteria:

  • Participants with TDT and SCD:
  • A willing and healthy 10/10 human leukocyte antigen (HLA)-matched related donor is available per investigator's judgement
  • Prior hematopoietic stem cell transplant (HSCT)
  • Clinically significant and active bacterial, viral, fungal, or parasitic infection as determined by the investigator
  • Participants with TDT:
  • Participants with associated α-thalassemia and >1 alpha deletion, or alpha multiplications
  • Participants with sickle cell β-thalassemia variant
  • Participants with SCD:
  • History of untreated moyamoya syndrome or presence of moyamoya syndrome at screening

Other protocol defined Inclusion/Exclusion criteria may apply.

Study Design

Enrollment

26 participants

Anticipated

Intervention Model

Single group

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: CTX001

CTX001 (autologous CD34+ hHSPCs modified with CRISPR-Cas9 at the erythroid lineage-specific enhancer of the BCL11A gene). Participants will receive a single infusion of CTX001 through a central venous catheter.

Interventions

CTX001

Administered by intravenous (IV) infusion following myeloablative conditioning with busulfan

Primary outcome measure

  • Fetal Hemoglobin (HbF) Concentration Over Time [ Time Frame: Up to 12 Months After CTX001 Infusion ]
  • Total Hemoglobin (Hb) Concentration Over Time [ Time Frame: Up to 12 Months After CTX001 Infusion ]

Central Contacts and Locations

Central contacts

Medical Information

6173416777medicalinfo@vrtx.com

Locations

New York Presbyterian Hospital - Morgan Stanley Children's Hospital

Recruiting

New York, New York, United States, 10032

Levine Children's Hospital - Hematology

Recruiting

Charlotte, North Carolina, United States, 28203

TriStar Medical Group Children's Specialists - Pediatric Oncology

Recruiting

Nashville, Tennessee, United States, 37203

More Information

Sponsor

Vertex Pharmaceuticals Incorporated

Last update posted

Mar 23, 2026

Last verified

Mar, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Vertex Pharmaceuticals Incorporated on 2026-03-23.