At Hospital Clinic of Barcelona, we have developed our own CART19 product (A3B1:CD8:41BB : CD3z or ARI-0001), which has been recently approved by the Spanish Medicines Agency (AEMPS) for the treatment of patients with relapsed/refractory acute lymphoblastic leukemia (ALL) older than 25 years of age (4). Here, CD8A is linked to acute lymphoblastic leukemia.