The main aim of this study is to collect real-world longitudinal data on participants with β-thalassemia treated with betibeglogene autotemcel (beti-cel) in the post marketing setting. To assess the long-term safety, including the risk of newly diagnosed malignancies, after treatment with beti-cel and evaluate the long-term effectiveness of treatment with beti-cel.

Inclusion Criteria:

• Participant must be treated with beti-cel in the post marketing setting at a center in the US that participates in the Registry.
• Participant must sign an informed consent and/or assent prior to enrollment as required under applicable laws and regulations.
• Participant must have signed an informed consent and/or assent permitting data to be shared with Center for International Blood and Marrow Transplant Research (CIBMTR).
• Participant must be followed by a hematologist based in the US.

Exclusion Criteria:

- There are no exclusion criteria for Registry participation.

Participants with β-thalassemia treated with beti-cel in the post marketing setting at a center in the United States (US) that participates in the Registry.

bluebird bio is committed to transparency. Appropriately de-identified participant-level datasets and supporting documents may be shared (if bluebird bio is contractually permitted to do so) following completion of this study, completion of all applicable regulatory submissions and consistent with criteria established by bluebird bio, our collaborators and/or industry best practices to protect confidential information and maintain the privacy of study participants. For enquiries, please contact us at datasharing@bluebirdbio.com.