Nevertheless, some groups of patients continue to fare poorly, including those with high-risk genetic drivers (e.g. E2A::HLF, KMT2A-rearranged BCP-ALL), certain age groups (e.g. infants, elderly), those with poor-risk second hit mutations (e.g. CREBBP-RAS) and those who relapse in the CNS. This evidence concerns the gene CREBBP and acute lymphoblastic leukemia.