Evaluation of Safety and Efficacy of CTX001 in Pediatric Participants With Transfusion-Dependent β-Thalassemia (TDT)

Prior treatment

• Prior hematopoietic stem cell transplant (HSCT)

Other illness

• Clinically significant and active bacterial, viral, fungal, or parasitic infection as determined by the investigator
  • Other protocol defined Inclusion/Exclusion criteria may apply.

Lab values

• A willing and healthy 10/10 human leukocyte antigen (HLA)-matched related donor is available per investigator's judgement

Other

• Participants with associated α-thalassemia and \>1 alpha deletion, or alpha multiplications
• Participants with sickle cell β-thalassemia variant

• Diagnosis of TDT as defined by:
  • Documented homozygous 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 mL/kilograms (kg)/year of packed RBC transfusions in the prior 24 months before signing of consent (or the last rescreening for patients going through repeat screening) or, for participants initiating transfusion therapy \<24 months before signing of consent, requirement for packed RBC transfusion at least every 3 to 4 weeks for ≥6 months
• Eligible for autologous stem cell transplant as per investigator's judgment.