Editas says levels of HBG1/2 promoter editing in hematopoietic stem cells

Editas Medicine (EDIT) shared new in vivo data demonstrating therapeutically relevant levels of HBG1/2 promoter editing in hematopoietic stem cells with a single dose of proprietary targeted lipid nanoparticle in non-human primates. This clinically validated approach targeting HBG1/2 promoters to upregulate fetal hemoglobin is in pre-clinical development as a potential transformative in vivo gene editing medicine for the treatment of sickle cell disease and beta thalassemia. The company reported these data in a presentation available today and will detail the data in a poster session on Saturday, June 14th 6:30 – 7:30 p.m. CEST at the European Hematology Association 2025 Congress in Milan, Italy. In this study, the company’s proprietary tLNP formulation delivered HBG1/2 promoter editing cargo to HSCs in NHPs. Latest data from this ongoing NHP study showed that at five months a single intravenous administration of Editas’ tLNP resulted in mean on-target editing levels in the HBG1/2 promoter region of 58% in HSCs: well exceeding the predicted editing threshold of 25% required for therapeutic benefit. In addition to achieving therapeutically relevant editing levels, the biodistribution data in NHPs with Editas’ tLNP continue to show significant de-targeting of the liver in contrast to standard LNPs. Editas Medicine’s in vivo HSC program targets HBG1/2 promoters to mimic naturally occurring mechanisms of hereditary persistence of fetal hemoglobin and utilizes proprietary AsCas12a to edit with high efficiency and minimize off-target editing. Editing the HBG1/2 promoters with AsCas12a with the investigational medicine reni-cel led to robust increases in HbF and total hemoglobin in clinical trials.