A Long-term Follow-up Study in Participants Who Received CTX001

A Long-term Follow-up Study of Subjects With β-thalassemia or Sickle Cell Disease Treated With Autologous CRISPR-Cas9 Modified Hematopoietic Stem Cells (CTX001)

This is a multi-site, open- label rollover study to evaluate the long-term safety and efficacy of CTX001 in pediatric and adult participants who received CTX001 in parent studies 111 (NCT03655678) 141 (NCT05356195) or 161 (NCT05477563) (transfusion-dependent β-thalassemia [TDT] studies) or Study 121 (NCT03745287) or 151 (NCT05329649) or 161(NCT05477563) (severe sickle cell disease [SCD] studies).

Inclusion Criteria:

• Participants (or his or her legally appointed and authorized representative or guardian) must sign and date informed consent form (ICF) and, where applicable, an assent form
• Participants must have received CTX001 infusion in a parent study

Exclusion Criteria:

• There are no exclusion criteria