Kamau Therapeutics released the first multi-patient clinical data for nula-cel, its gene edited stem cell therapy for severe sickle cell disease, on November 4. The data come from the Phase 1/2 RESTORE trial and will be presented orally at the American Society of Hematology annual meeting on December 14, 2026, in New Orleans.
Three patients were treated with the revised V2.0 manufacturing process. All three achieved transfusion independence before hospital discharge, and no vaso-occlusive events have occurred in any patient after infusion, the company said. Neutrophil engraftment came at a median of 21 days, in a range of 19 to 32 days, and no serious adverse events related to nula-cel or the editing procedure were observed in these patients.
In the two patients with more than six months of follow up, total haemoglobin exceeded 10 grams per decilitre, at 10.2 and 11.1, with sickle haemoglobin at 17.6 percent at 12 months and 19.1 percent at 8 months, and adult haemoglobin at 76.8 percent and 66.8 percent respectively. Bone marrow homology directed repair allele frequencies stabilised at about 20 percent, and single cell analyses showed more than 90 percent of circulating red blood cells contained protective levels of anti-sickling haemoglobin. Follow up also continues for the first patient ever treated, four years after infusion under the earlier process.
The distinction from the approved therapy Casgevy matters. Casgevy works by switching on fetal haemoglobin. Kamau uses homology directed repair to replace the mutated beta globin gene directly with a healthy copy, restoring adult haemoglobin. The company, co-founded by Stanford physician scientist Matthew Porteus, emerged from stealth with this release. The trial is enrolling about 15 participants, so the dataset is three patients deep and the durability claim rests substantially on one four year case.