{"groups":[{"description":"Participants with relapsed or refractory B-precursor acute lymphoblastic leukemia (r/r B-ALL) received conditioning chemotherapy (fludarabine 25 mg/m\\^2 intravenously \\[IV\\] over 30 minutes on Day -4, Day -3, and Day -2 and cyclophosphamide 900 mg/m\\^2 IV over 60 minutes on Day -2) followed by a single infusion of brexucabtagene autoleucel (KTE-X19) chimeric antigen receptor (CAR) transduced autologous T cells administered IV at a target dose of 2 x 10\\^6 anti-CD19 CAR T cells/kg of body weight on Day 0. For participants weighing \\> 100 kg, a maximum flat dose of 2 x 10\\^8 anti-CD19 CAR T cells/kg of body weight was administered.","id":"FG000","title":"Phase 1: 2 x 10^6 Anti-CD19 CAR T Cells/kg"},{"description":"Participants with r/r B-ALL received conditioning chemotherapy (fludarabine 25 mg/m\\^2 IV over 30 minutes on Day -4, Day -3, and Day -2 and cyclophosphamide 900 mg/m\\^2 IV over 60 minutes on Day -2) followed by a single infusion of brexucabtagene autoleucel CAR transduced autologous T cells administered IV at a target dose of 1 x 10\\^6 anti-CD19 CAR T cells/kg of body weight on Day 0. For participants weighing \\> 100 kg, a maximum flat dose of 1 x 10\\^8 anti-CD19 CAR T cells/kg of body weight was administered.","id":"FG001","title":"Phase 1: 1 x 10^6 Anti-CD19 CAR T Cells/kg"},{"description":"Participants with r/r B-ALL received conditioning chemotherapy (fludarabine 25 mg/m\\^2 IV over 30 minutes on Day -4, Day -3, and Day -2 and cyclophosphamide 900 mg/m\\^2 IV over 60 minutes on Day -2) followed by a single infusion of brexucabtagene autoleucel CAR transduced autologous T cells administered IV at a target dose of 0.5 x 10\\^6 anti-CD19 CAR T cells/kg of body weight on Day 0. For participants weighing \\> 100 kg, a maximum flat dose of 0.5 x 10\\^8 anti-CD19 CAR T cells/kg of body weight was administered.","id":"FG002","title":"Phase 1: 0.5 x 10^6 Anti-CD19 CAR T Cells/kg"},{"description":"Participants with r/r B-ALL received conditioning chemotherapy (fludarabine 25 mg/m\\^2 IV over 30 minutes on Day -4, Day -3, and Day -2 and cyclophosphamide 900 mg/m\\^2 IV over 60 minutes on Day -2) followed by a single infusion of brexucabtagene autoleucel CAR transduced autologous T cells administered IV at a target dose of 1 x 10\\^6 anti-CD19 CAR T cells/kg of body weight on Day 0. For participants weighing \\> 100 kg, a maximum flat dose of 1 x 10\\^8 anti-CD19 CAR T cells/kg of body weight was administered.","id":"FG003","title":"Phase 2: 1 x 10^6 Anti-CD19 CAR T Cells/kg"}],"periods":[{"dropWithdraws":[{"reasons":[{"groupId":"FG000","numSubjects":"6"},{"groupId":"FG001","numSubjects":"14"},{"groupId":"FG002","numSubjects":"11"},{"groupId":"FG003","numSubjects":"29"}],"type":"Death"},{"reasons":[{"groupId":"FG000","numSubjects":"0"},{"groupId":"FG001","numSubjects":"1"},{"groupId":"FG002","numSubjects":"0"},{"groupId":"FG003","numSubjects":"8"}],"type":"Full consent withdrawn"},{"reasons":[{"groupId":"FG000","numSubjects":"0"},{"groupId":"FG001","numSubjects":"2"},{"groupId":"FG002","numSubjects":"2"},{"groupId":"FG003","numSubjects":"2"}],"type":"Lost to Follow-up"},{"reasons":[{"groupId":"FG000","numSubjects":"0"},{"groupId":"FG001","numSubjects":"5"},{"groupId":"FG002","numSubjects":"4"},{"groupId":"FG003","numSubjects":"16"}],"type":"Enrolled but did not Initiate KTE-X19"},{"reasons":[{"groupId":"FG000","numSubjects":"0"},{"groupId":"FG001","numSubjects":"4"},{"groupId":"FG002","numSubjects":"2"},{"groupId":"FG003","numSubjects":"15"}],"type":"Rolled over or consented to a long term follow-up (LFTU) study"},{"reasons":[{"groupId":"FG000","numSubjects":"0"},{"groupId":"FG001","numSubjects":"2"},{"groupId":"FG002","numSubjects":"1"},{"groupId":"FG003","numSubjects":"1"}],"type":"Reason not specified"}],"milestones":[{"achievements":[{"groupId":"FG000","numSubjects":"6"},{"groupId":"FG001","numSubjects":"28"},{"groupId":"FG002","numSubjects":"20"},{"groupId":"FG003","numSubjects":"71"}],"type":"STARTED"},{"achievements":[{"groupId":"FG000","numSubjects":"0"},{"groupId":"FG001","numSubjects":"0"},{"groupId":"FG002","numSubjects":"0"},{"groupId":"FG003","numSubjects":"0"}],"type":"COMPLETED"},{"achievements":[{"groupId":"FG000","numSubjects":"6"},{"groupId":"FG001","numSubjects":"28"},{"groupId":"FG002","numSubjects":"20"},{"groupId":"FG003","numSubjects":"71"}],"type":"NOT COMPLETED"}],"title":"Overall Study"}],"preAssignmentDetails":"173 participants were screened. Bridging therapy was recommended for all participants particularly those participants with high disease burden at baseline (M3 marrow \\[\\> 25% leukemic blasts\\] or ≥ 1,000 blasts/mm\\^3 in the peripheral circulation) to control participant's disease post apheresis/enrollment and prior to conditioning chemotherapy.","recruitmentDetails":"Participants were enrolled at study sites in France, Germany, the Netherlands, and the United States."}