Related Experiment Video
Updated: Jun 28, 2025

Detection of Residual Donor Erythroid Progenitor Cells after Hematopoietic Stem Cell Transplantation for Patients with Hemoglobinopathies
Published on: September 6, 2017
Exagamglogene Autotemcel for Transfusion-Dependent β-Thalassemia
Franco Locatelli1, Peter Lang1, Donna Wall1
1From IRCCS Ospedale Pediatrico Bambino Gesù (F.L., M.A.) and Catholic University of the Sacred Heart (F.L.), Rome, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan (M.D.C.), and the Department of Health Sciences, Magna Graecia University, Catanzaro (M.A.) - all in Italy; University Children's Hospital Tübingen (R.H.), and the Cluster of Excellence iFIT (EXC 2180) "Image-guided and Functionally Instructed Tumor Therapies" and the German Cancer Consortium, Partner Site Tübingen, University of Tübingen (P.L.), Tübingen, the Division of Pediatric Stem Cell Therapy, Department of Pediatric Oncology, Hematology, and Clinical Immunology, Medical Faculty, Heinrich Heine University, Düsseldorf (R.M.), and the University of Regensburg, Regensburg (S.C.) - all in Germany; the Hospital for Sick Children and University of Toronto, Toronto (D.W.), and BC Children's Hospital, University of British Columbia, Vancouver (A.M.L.) - all in Canada; Imperial College Healthcare NHS Trust, St. Mary's Hospital (J.F.), and University College London Hospitals NHS Foundation Trust (B.C.) - both in London; Stanford University, Palo Alto, CA (A.J.S.); Children's Hospital of Philadelphia and Perlman School of Medicine, University of Pennsylvania, Philadelphia (J.L.K., S.G.); Herbert Irving Comprehensive Cancer Center, Columbia University (M.M.), and Joan and Sanford I. Weill Medical College of Cornell University (S.S.) - both in New York; Ann and Robert H. Lurie Children's Hospital of Chicago, Chicago (R.I.L.); National and Kapodistrian University of Athens, Athens (A.K.); Vertex Pharmaceuticals, Boston (P.K., D.S., L.R., Y.B., C.S., L.Z., W.E.H.), and CRISPR Therapeutics, Cambridge (P.K.M.) - both in Massachusetts; and Sarah Cannon Research Institute at the Children's Hospital at TriStar Centennial, Nashville (H.F.).
Exagamglogene autotemcel (exa-cel) gene therapy achieved transfusion independence in 91% of transfusion-dependent beta-thalassemia patients. This CRISPR-Cas9 treatment reactivates fetal hemoglobin, offering a significant advancement in managing this genetic blood disorder.
Area of Science:
- Hematology
- Gene Therapy
- Genetics
Background:
- Exagamglogene autotemcel (exa-cel) is a nonviral cell therapy utilizing CRISPR-Cas9 gene editing.
- It targets the BCL11A erythroid-specific enhancer region in autologous CD34+ hematopoietic stem and progenitor cells (HSPCs).
- The therapy aims to reactivate fetal hemoglobin (HbF) synthesis.
Purpose of the Study:
- To evaluate the efficacy and safety of exa-cel in patients with transfusion-dependent beta-thalassemia.
- To assess the rate of transfusion independence achieved with exa-cel treatment.
Main Methods:
- An open-label, single-group, phase 3 study was conducted.
- Patients aged 12-35 with transfusion-dependent beta-thalassemia received exa-cel after myeloablative conditioning with busulfan.
- CRISPR-Cas9 gene editing of HSPCs was performed ex vivo.
Main Results:
- 91% of patients (32 out of 35 with sufficient follow-up) achieved transfusion independence.
- The median follow-up was 20.4 months.
- During transfusion independence, mean total hemoglobin was 13.1 g/dL and mean fetal hemoglobin was 11.9 g/dL, with pancellular distribution.
Conclusions:
- Exa-cel treatment, preceded by myeloablation, resulted in high rates of transfusion independence in beta-thalassemia patients.
- The safety profile was consistent with myeloablative busulfan conditioning and autologous HSPC transplantation.
- No deaths or cancers were reported during the study.
More Related Videos
05:23Continuous Manual Exchange Transfusion for Patients with Sickle Cell Disease: An Efficient Method to Avoid Iron Overload
Published on: March 14, 2017
07:24A Precision Medicine Tool for Measurement and Monitoring of Hemoglobin S in Sickle Cell Disease Patients Receiving Transfusion Therapy
Related Concept Videos
Blood Transfusion
Blood Transfusion Overview
A blood transfusion is a medical procedure used to replace blood lost due to injury, surgery, or to treat conditions such as anemia or cancer. During a transfusion, donor blood is...
Blood Transfusion and Agglutination
History
The history of blood transfusion dates back to the 17th century, when early attempts were made in animals. In 1818 James Blundell, a British doctor, performed the first successful human blood transfusion. Later in 1900, Karl...
Bone Marrow Sampling and Transplants
The transplant begins with high doses of chemotherapy and radiation treatment, which aim to destroy...