NEW YORK – The US Food and Drug Administration has accepted Vertex Pharmaceuticals and CRISPR Therapeutics' biologics license applications (BLA) seeking approval for exagamglogene autotemcel (exa-cel) as a gene-editing therapy for sickle cell disease (SCD) and transfusion-dependent beta-thalassemia (TDT), the companies announced late Thursday.
Boston-based Vertex and Zug, Switzerland-based CRISPR Therapeutics in April submitted BLAs for their investigational therapy in severe SCD, which will undergo priority review at the FDA, and TDT, which will undergo the standard review process. The FDA is expected to issue a decision on exa-cel's SCD indication by Dec. 8, and decide by March 30, 2024, on the TDT indication.
Exa-cel uses CRISPR-Cas9 to edit patients' CD34-positive hematopoietic stem and progenitor cells ex vivo to alter the BCL11A gene, in an effort to reactivate high levels of fetal hemoglobin in red blood cells after infusion back into the body. Fetal hemoglobin is a protein that carries oxygen and is lacking or dysfunctional in patients with SCD and TDT.
Exa-cel could be the first CRISPR gene-editing therapy to be approved by the FDA, Vertex CEO and President Reshma Kewalramani said in a statement. Vertex leads global development, manufacturing, and commercialization efforts for exa-cel and splits program costs and profits 60-40 with CRISPR Therapeutics.
The companies have submitted interim data from pivotal trials to the FDA, showing that 16 out of 17 patients on exa-cel for SCD didn't experience any severe vaso-occlusive crises for at least 12 months after treatment, and 24 out of 27 patients who received exa-cel for TDT achieved transfusion-independence for at least 12 months after treatment. The firms will share data from the trials next week at the European Hematology Association Congress in Germany.
In Europe, Vertex and CRISPR Therapeutics' marketing authorization application for exa-cel was validated by the European Medicines Agency and the UK Medicines and Healthcare products Regulatory Agency in January. These agencies could make a regulatory decision on exa-cel this year.