First Patients to Receive CRISPR for SCD, Beta Thalassemia Continue to Improve

Updated results published in the New England Journal of Medicine and presented at the 2020 American Society of Hematology (ASH) Annual Meeting show that the first patients with sickle cell disease (SCD) to be treated with the CRISPR/Cas9-based gene editing platform CTX001 have not experienced vaso-occlusive crises or hospitalizations since receiving the treatment.

The first patient with SCD in the U.S. to undergo the treatment with CTX001 has continued to improve over the last 18 months, according to an interview with her treating physician. Having experienced an average of seven episodes per year prior to treatment, the patient has also been able to discontinue the pain medications she has required for most of her life.

In addition, seven patients with beta thalassemia who enrolled in the study of CTX001 have not required blood transfusions since receiving the treatment.

“It is opening the door for us to show that this therapy can not only be used in sickle cell and thalassemia but potentially can be used in other disorders … We are very proud and very happy to be part of this – really a breakthrough in medicine,” said lead author Haydar Frangoul, MD, of TriStar Centennial Health in Nashville, Tennessee.

No serious adverse events (AEs) related to CTX001 were reported in the patients with SCD, while four were reported in one patient with beta thalassemia: headache, hemophagocytic lymphohistiocytosis (HLH), acute respiratory distress syndrome, and idiopathic pneumonia syndrome. These AEs occurred in the context of HLH and either resolved or were improving at the time of analysis, the study authors said.

Sources: News Channel 5 Nashville, December 22, 2020; NPR, December 15, 2020; Frangoul H, Bobruff Y, Cappellini MD, et al. Safety and Efficacy of CTX001 in Patients with Transfusion-Dependent β-Thalassemia and Sickle Cell Disease: Early Results from the Climb THAL-111 and Climb SCD-121 Studies of Autologous CRISPR-CAS9–Modified CD34+ Hematopoietic Stem and Progenitor Cells. Abstract 4. Presented at the 2020 American Society of Hematology Annual Meeting; December 6, 2020.