Because this is a blood based disease, I’m guessing they would extract blood from the patient or extract them from bone marrow (more likely), treat the cells ou

Because this is a blood based disease, I’m guessing they would extract blood from the patient or extract them from bone marrow (more likely), treat the cells outside the body, and then transfuse the modified blood cells back onto the patient to try and engraftment them in the bone marrow. All of the hard CRISPR stuff is likely in vitro. However, I don’t know anything about what the specific plans are though, this is just speculation.