A phase 1/2 study is being conducted to determine whether blinatumomab with pembrolizumab (anti-PD-1) improves efficacy versus blinatumomab monotherapy in adults with R/R BCP-ALL with a high percentage of bone marrow blasts (> 50% lymphoblasts) (NCT03512405) [62]. This evidence concerns the gene PDCD1 and acute lymphoblastic leukemia.