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 2 years.
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
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.
Prior hematopoietic stem cell transplantation (HCT)
Recent history of the extramedullary disease (EMD) that requires ongoing radiographic surveillance (e.g., participants with active EMD at CD19 CART infusion that requires monitoring by imaging without the ability to more precisely assess disease status will be ineligible). A remote history of EMD does not exclude the participant.
Active and/or residual central nervous system (CNS) disease that requires ongoing therapy or monitoring.
Co-morbidities precluding myeloablative HCT. Note: Determination of co-morbidities precluding myeloablative HCT will be made by the treating transplant (HCT) physician and documented in the research record. This does not require that the participant is immediately fully eligible for HCT, only that there are no long-term comorbidities that would preclude a myeloablative approach (e.g., renal failure, severe cardiac failure, long-term oxygen requirement).