For some patients who receive cell therapy such as CAR-T cells, this comes after many other treatments have failed. Researchers noticed that their patients who received the cells while in remission tended to do well after their infusion. They proposed a research study to follow patients who had received a transplant and/or cell therapy. The study included data from 134 patients in the registry who had entered complete remission during the waiting period before receiving their cell therapy. They found that this group of patients had a 43% probability of progression-free survival in the two years following their treatment, roughly the same percentage as patients in the registry who were not in remission when they received CAR-T. Patients in remission had very low levels of toxicities associated with their cell therapies, namely an excessive immune response known as cytokine release syndrome and neurotoxicity, two side effects that can sometimes accompany CAR-T cell therapy.