Two Patients Become Transfusion Independent After Gene Editing Therapy
June 12, 2020 – CRISPR Therapeutics and Vertex Pharmaceuticals have announced early results from their CLIMB Thal-111 Study in which transfusion-dependent beta thalassemia patients are treated with a gene editing therapy called CTX001. CTX001 is a therapy that involves CRISPR/Cas9 gene editing of a patient’s own hematopoietic stem cells (HSCs) in order to reactivate fetal hemoglobin production. The results of the first two patients treated in the CLIMB Thal-111 Study are now available:
Patient 1 has the β0/IVS-I-110 genotype, which is associated with a severe phenotype similar to β0/β0, and had a transfusion requirement of 34 units of packed red blood cells per year. At 15 months after CTX001 infusion, this patient was transfusion independent and had a total hemoglobin level of 14.2 g/dL, with a fetal hemoglobin level of 13.5 g/dL.
Patient 2 has the β0/IVS-II-745 genotype and had a transfusion requirement of 61 units of packed red blood cells per year. At 5 months after CTX001 infusion, this patient was transfusion independent and had a total hemoglobin level of 12.5 g/dL, with a fetal hemoglobin level of 12.2 g/dL.
The CLIMB Thal-111 Study in Transfusion-Dependent Thalassemia has dosed a total of 5 patients to date, all of whom have successfully engrafted. In addition, CLIMB Thal-111 has been expanded to allow enrollment of β0/β0 patients, and is also being expanded to allow enrollment of pediatric patients ages 12 years or older.
Further information about these findings is available in the press release at: http://ir.crisprtx.com/news-releases/news-release-details/crispr-therapeutics-and-vertex-announce-new-clinical-data