Prior to initial tisagenlecleucel cell infusion, lymphodepleting chemotherapy (LDC) is required with standard dosing cyclophosphamide and fludarabine as per standard-of-care (fludarabine 30mg/m^2 /dose x 4 doses and cyclophosphamide 500mg/m^2 /dose x 2 doses). Dose adjustments based off ideal body weight (IBW) and/or per institutional guidelines are allowed. LDC should be completed 2 to 14 days prior to the first tisagenlecleucel infusion. LDC may be repeated in cases where tisagenlecleucel has been delayed by more than 4 weeks. No additional LDC will be given prior to the early reinfusion.
The researchers are doing this study to see if early reinfusion of tisagenlecleucel can keep participants in B-CEll ApLasia at 6 months after their first infusion. The researchers will also look at the safety of early reinfusion and how effective it is at treating B-ALL.