A Pilot Trial to Evaluate Next-Generation Sequencing (NGS) Testing and Monitoring of B-Cell Recovery to Guide Management Following CAR T-cell Induced Remission in Pediatric Patients With B Lineage Acute Lymphoblastic Leukemia
Background: Chimeric antigen receptor T-cell (CART) therapy is a form of immunotherapy which can be used to treat people with relapsed B-ALL. For those who achieve remission after CART alone, it may cure up to 50% of people who receive this therapy. However, for people who relapse after CART, it can be hard to achieve remission again. In patients where CART fails, stem cell transplant (HCT) can be used to prevent relapse and achieve cure. But HCT can cause serious side effects. Better testing is needed to distinguish people who can be cured with CART alone from people who may also need to have HCT.
Objective: To see if the use of a series of blood and bone marrow tests at regular intervals can help monitor for B-ALL relapse after CART therapy.
Eligibility: People aged 1 to 25 years with B-ALL who have had CART therapy within the past 42 days. They must never have had a blood stem cell transplant; they must also have no measurable blood cancer cells.
Design: Participants will visit the clinic every 2 weeks starting 42 days after they receive CART therapy. Each visit will be about the same amount of time as a regular clinic visit. about 8 hours. Participants will have blood drawn for testing on each visit. Bone marrow biopsy/aspirate will be done during 4 of the visits at routine timepoints after CART. A needle will be inserted to draw a sample of tissue from inside the bone in the hip. A small amount of blood and tissue will be tested with ClonoSEQ and to evaluate for normal B-cells side by side with the standard tests. The combined testing may help determine whether participants are eligible for HCT and/or at risk of relapse after CART. Participants will be in the study for 1 year
• Age \>=1 year and \<= 25 years old at the time of CD19 CART infusion
• Confirmed diagnosis of CD19+ B-ALL with an informative NGS clonality sample
⁃ -Have an informative NGS clonality sample for MRD assessment based on immunoglobulin rearrangement in bone marrow or blood at any time of active disease between diagnosis and CD19 CART infusion and any time prior to the first on-study intervention confirmed by NGS MRD testing.
• Post-CD19 CART infusion disease status:
‣ Are in bone marrow morphologic complete remission and are flow cytometry measurable residual disease (MRD) negative within 42 days post CD19 CART infusion.
⁃ Are NGS MRD negative by tracking sample in the bone marrow within 42 days post CD19 CART infusion confirmed by NGS MRD testing.
• Received first CD19 (4-1BB) CART within 42 days prior to enrollment. Note: Eligible CART including FDA approved Kymriah (tisagenlecleucel) infused on a treatment plan, research study, or other comparable 4-1BB based constructs.
∙ Study chairs will determine whether other 4-1BB CART are considered comparable.
• All participants must have an allogeneic HCT donor identified for potential HCT. Note: Donor identification and selection will be according to institutional practice.
• Have B-cell aplasia (BCA) post CD19 CART persisting within 42 days post CD19 CART infusion. Note: BCA persisting is defined as \<1% B cells lymphocytes or \<50 B cells/microliter in the peripheral blood
• Performance of all screening tests prior to day 42 post CD19 CART.
• The ability of participant or parent/guardian to understand and the willingness to sign a written consent document or participants unable to consent if they are represented by a Legally Authorized Representative (LAR).