Evaluating CTX001 for treating severe sickle cell disease in children

A Phase 3 Study to Evaluate the Safety and Efficacy of a Single Dose of CTX001 in Pediatric Subjects With Severe Sickle Cell Disease

Phase 3 Interventional Vertex Pharmaceuticals Incorporated · NCT05329649

This study is testing a one-time treatment using a new gene-editing method to see if it can help children with severe sickle cell disease who haven't responded to other medications.

Quick facts

PhasePhase 3
Study typeInterventional
Enrollment15 (estimated)
Ages2 Years to 11 Years
SexAll
SponsorVertex Pharmaceuticals Incorporated Industry-sponsored
Locations7 sites (Charlotte, North Carolina and 6 other locations)
Trial IDNCT05329649 on ClinicalTrials.gov

What this trial studies

This interventional phase 3 trial assesses the safety and efficacy of a single-dose treatment using CTX001, which involves modifying a patient's own hematopoietic stem and progenitor cells with CRISPR-Cas9 technology. The study focuses on pediatric participants diagnosed with severe sickle cell disease who have either failed hydroxyurea treatment or are intolerant to it. Participants will be monitored for adverse effects and treatment outcomes over the course of the study.

Who should consider this trial

Good fit: Ideal candidates are pediatric patients with severe sickle cell disease who have experienced hydroxyurea failure or intolerance.

Not a fit: Patients with a willing and healthy 10/10 HLA-matched related donor or those who have previously undergone hematopoietic stem cell transplant may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could significantly improve the quality of life and health outcomes for children suffering from severe sickle cell disease.

How similar studies have performed: Other studies utilizing CRISPR technology for genetic disorders have shown promising results, indicating potential for success in this novel approach.

Eligibility criteria

Show full inclusion / exclusion criteria
Key Inclusion Criteria:

* 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
* Hydroxyurea (HU) failure unless HU intolerant
* Eligible for autologous stem cell transplant as per investigators judgment

Key Exclusion Criteria:

* A willing and healthy 10/10 human leukocyte antigen (HLA)-matched related donor
* Prior hematopoietic stem cell transplant (HSCT).
* Clinically significant and active bacterial, viral, fungal, or parasitic infection

Other protocol defined Inclusion/Exclusion criteria may apply.

Where this trial is running

Charlotte, North Carolina and 6 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Sickle Cell DiseaseHydroxyurea FailureHydroxyurea IntoleranceHemoglobinopathiesHematological Diseases
Last reviewed 2026-06-10 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.