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Published on: March 14, 2017
Exagamglogene Autotemcel for Severe Sickle Cell Disease
Haydar Frangoul1, Franco Locatelli1, Akshay Sharma1
1From Sarah Cannon Research Institute at the Children's Hospital at TriStar Centennial (H.F.), Nashville, and Bone Marrow Transplantation and Cellular Therapy, St. Jude Children's Research Hospital, Memphis (A.S.) - both in Tennessee; IRCCS, Ospedale Pediatrico Bambino Gesù, Catholic University of the Sacred Heart, Rome (F.L.); the Department of Pediatrics, Columbia University Irving Medical Center, New York-Presbyterian-Morgan Stanley Children's Hospital (M.B.), and the Department of Medicine, Division of Hematology-Oncology, Columbia University (M. Mapara) - both in New York; Sarah Cannon Pediatric Transplant and Cellular Therapy Program at Methodist Children's Hospital, San Antonio, TX (L.M., M.J.E.); the Hospital for Sick Children and the University of Toronto, Toronto (D.W.); Ann and Robert H. Lurie Children's Hospital of Chicago (R.I.L.) and the University of Illinois at Chicago (D.R.) - both in Chicago; Royal London Hospital, Barts Health NHS Trust, London (P.T.); Stanford University, Palo Alto (A.J.S.), and University of California San Francisco Benioff Children's Hospital, Oakland (M.C.W.) - both in California; the Biotherapy Department and Biotherapy Clinical Investigation Center (M.C.), Necker-Enfants Malades Hospital, Assistance Publique-Hopitaux de Paris, Université Paris-Cité (M. de Montalembert), Paris; the University of Regensburg, Regensburg (S.C.), the Division of Pediatric Stem Cell Therapy, Department of Pediatric Oncology, Hematology, and Clinical Immunology, Medical Faculty, Heinrich Heine University, Duesseldorf (R.M.), and Gemeinschaftsklinikum Mittelrhein, Koblenz (S.L.) - all in Germany; Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles, Brussels (L.D.); Boston University Chobanian and Avedisian School of Medicine (M.H.S.) and Vertex Pharmaceuticals (S.I., L.B., C.S., W.Z., F.X., W.E.H.), Boston, and CRISPR Therapeutics, Cambridge (P.K.M.) - all in Massachusetts; and the Division of Oncology, Children's Hospital of Philadelphia, Perelman School of Medicine at the University of Pennsylvania, Philadelphia (S.A.G.).
Exagamglogene autotemcel (exa-cel) gene therapy effectively eliminated severe vaso-occlusive crises in 97% of sickle cell disease patients for over 12 months. This groundbreaking treatment offers a new therapeutic option for sickle cell disease management.
Area of Science:
- Hematology
- Gene Therapy
- Cellular Medicine
Background:
- Exagamglogene autotemcel (exa-cel) is a novel nonviral cell therapy utilizing CRISPR-Cas9 gene editing.
- It targets autologous CD34+ hematopoietic stem and progenitor cells (HSPCs) to reactivate fetal hemoglobin synthesis.
- The editing is focused on the erythroid-specific enhancer region of the BCL11A gene.
Purpose of the Study:
- To evaluate the efficacy and safety of exa-cel in patients with sickle cell disease.
- To assess the primary endpoint of freedom from severe vaso-occlusive crises for at least 12 consecutive months.
- To determine the secondary endpoint of freedom from inpatient hospitalization for severe vaso-occlusive crises for at least 12 consecutive months.
Main Methods:
- A phase 3, single-group, open-label study was conducted.
- Participants were patients aged 12 to 35 years with sickle cell disease and a history of severe vaso-occlusive crises.
- HSPCs were edited ex vivo using CRISPR-Cas9, followed by myeloablative busulfan conditioning and exa-cel infusion.
Main Results:
- A total of 44 patients received exa-cel, with a median follow-up of 19.3 months.
- 97% of evaluable patients (29/30) were free from vaso-occlusive crises for at least 12 months.
- 100% of evaluable patients (30/30) were free from hospitalizations for vaso-occlusive crises for at least 12 months.
- The safety profile was consistent with myeloablative conditioning and autologous HSPC transplantation; no cancers were reported.
Conclusions:
- Exa-cel treatment demonstrated high efficacy in eliminating vaso-occlusive crises in sickle cell disease patients.
- The therapy achieved sustained freedom from severe vaso-occlusive crises and hospitalizations for at least 12 months.
- Exa-cel represents a significant advancement in the treatment of sickle cell disease.
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