The aim of this article is to provide consensus opinion from experts in the fields of hematopoietic cell transplantation, cellular immunotherapy, and lymphoma regarding key clinical questions pertinent to the use of CD19 CAR T cell products for the treatment of NHL.
The remarkable clinical response rates achieved by adoptive transfer of T cells that target CD19 in patients with leukemia and lymphoma have led to a growing number of clinical trials exploring CAR T-cell therapy for solid tumors.
We found that UCB-19BBzeta and UCB-28BBzeta T cells exhibited more cytotoxicity to CD19(+) leukemia and lymphoma cell lines than UCB-19zeta and UCB-1928zeta, although differences in secretion of interleukin-2 and interferon-gamma by these T cells were not evident.
Adoptive therapy using purified T(CM) cells is now the subject of a Food and Drug Administration-authorized clinical trial for the treatment of CD19(+) B-cell malignancies, and 3 clinical cell products expressing a CD19-specific CAR for IND #14645 have already been successfully generated from lymphoma patients using this manufacturing platform.
Effective clinical treatment with anti-CD19 CAR T cells was first reported in 2010 after a patient with advanced-stage lymphoma treated at the NCI experienced a partial remission of lymphoma and long-term eradication of normal B cells.
In this regard, CD19-specific CAR T cell therapies have achieved dramatic objective responses for a high percent of patients with CD19-positive leukemia or lymphoma.
Our data provide evidence that CD19 plays an important role in transmitting survival and proliferation signals downstream of CD40 and therefore might be an interesting therapeutic target for the treatment of lymphoma undergoing chronic CD40 signaling.
T cells can also be genetically modified with chimeric antigen receptors (CARs) to confer specificity for surface antigens, and studies of CD19 CARs in lymphoma also have had encouraging response rates.
Early trials with anti-CD19 CAR T cells have achieved spectacular remissions in B-cell leukemia and lymphoma, so far refractory, very recently resulting in the Food and Drug Administration approval of CD19 CAR T cells for therapy.
The engineered CD4(+) T cells and CD8(+) T cells both exhibited specific cytotoxicity against CD19(+) leukemia and lymphoma cell lines, as well as against CD19 transfectants, and produced high-levels of antigen-dependent Th1 (but not Th2) cytokines.
We conducted a clinical trial to assess the safety and efficacy of CD19-targeting CAR-T-cells in the treatment of relapsed and chemotherapy-refractory B-ALL and lymphoma.
The use of double staining with CD 5/CD 19 antibodies accompanied by two-color flow cytometric analysis clearly defined the chronic lymphocytic leukemia population and separated it from the lymphoma population.
The MP1-specific CTLs are amenable to subsequent genetic modification to express a CD19-specific CAR, designated CD19R, and acquire HLA-unrestricted reactivity toward CD19(+) leukemia and lymphoma tumor targets while maintaining HLA-restricted MP1 specificity.
More than 200 CAR T cell clinical trials have been initiated so far, most of which aim to treat lymphoma or leukemia patients using CD19-specific CARs.