Second Infusion of Tisagenlecleucel for Children and Young Adults with B-Cell Acute Lymphoblastic Leukemia (B-ALL)

Inclusion Criteria

• Patients with relapsed or refractory B-ALL who have already received tisagenlecleucel and have more doses available for early reinfusion.
• History of CD19 positive B-ALL before receiving tisagenlecleucel.
• B-Cell Aplasia (BCA) in the blood within 14 days before reinfusion, defined as a B lymphocyte count of 50 or fewer per microliter.
• Complete remission of the disease in the bone marrow within 14 days before reinfusion, including no disease outside the bone marrow.
• Patients with tisagenlecleucel that is out of specification (OOS) can participate if the OOS reason does not affect the treatment's safety and effectiveness.
• Patients must be under 26 years old at the time of the first tisagenlecleucel order.
• Recovery from severe side effects of the initial tisagenlecleucel dose, such as cytokine release syndrome (CRS) and neurotoxicity.
• Adequate organ function, including liver, kidney, heart, and lung function, as determined by specific medical tests.
• Good overall health status, with specific performance scores based on age.
• Enrollment in a related reporting protocol for immune effector cells.
• Willingness to participate in the study, with informed consent signed by the patient or legal guardian, and assent from patients aged 7 to 17.

Exclusion Criteria

• More than 60 days have passed since the first tisagenlecleucel infusion.
• Ongoing severe side effects from the initial CAR T cell infusion.
• Received non-standard chemotherapy before the first tisagenlecleucel dose.
• Loss of B-Cell Aplasia before reinfusion.
• Active, significant infection confirmed by medical tests.
• Inability to give informed consent or follow the treatment plan.
• Pregnant or breastfeeding women, or women who can become pregnant unless using effective birth control during and after treatment.
• Sexually active males unless willing to use a condom during and after treatment.
• Other uncontrolled illnesses or conditions that could interfere with the study or pose a risk to the patient.
• Any other reason deemed by the doctor to make the patient ineligible for the study.