CD19 CAR T cells following autologous transplantation in poor-risk relapsed and refractory B-cell non-Hodgkin lymphoma

Abstract

High-dose chemotherapy and autologous stem cell transplantation (HDT-ASCT) is the standard of care for relapsed or primary refractory (rel/ref) chemorefractory diffuse large B-cell lymphoma. Only 50% of patients are cured with this approach. We investigated safety and efficacy of CD19-specific chimeric antigen receptor (CAR) T cells administered following HDT-ASCT. Eligibility for this study includes poor-risk rel/ref aggressive B-cell non-Hodgkin lymphoma chemosensitive to salvage therapy with: (1) positron emission tomography-positive disease or (2) bone marrow involvement. Patients underwent standard HDT-ASCT followed by 19-28z CAR T cells on days +2 and +3. Of 15 subjects treated on study, dose-limiting toxicity was observed at both dose levels (5 × 10⁶ and 1 × 10⁷ 19-28z CAR T per kilogram). Ten of 15 subjects experienced CAR T-cell-induced neurotoxicity and/or cytokine release syndrome (CRS), which were associated with greater CAR T-cell persistence (P = .05) but not peak CAR T-cell expansion. Serum interferon-γ elevation (P < .001) and possibly interleukin-10 (P = .07) were associated with toxicity. The 2-year progression-free survival (PFS) is 30% (95% confidence interval, 20% to 70%). Subjects given decreased naive-like (CD45RA⁺CCR7⁺) CD4⁺ and CD8⁺ CAR T cells experienced superior PFS (P = .02 and .04, respectively). There was no association between CAR T-cell peak expansion, persistence, or cytokine changes and PFS. 19-28z CAR T cells following HDT-ASCT were associated with a high incidence of reversible neurotoxicity and CRS. Following HDT-ASCT, effector CD4⁺ and CD8⁺ immunophenotypes may improve disease control. This trial was registered at www.clinicaltrials.gov as #NCT01840566.

Graphical abstract

Figure 1.

Study treatment schema. BEAM, carmustine, etoposide, cytarabine, and melphalan.

Figure 2.

Toxicity related to 19-28z CAR T-cell expansion. (A) Persistence in days was longer in subjects experiencing severe toxicity. (B) No significant difference was seen in peak values of vector copy number (VCN) per microliter by quantitative PCR.

Figure 3.

Serum cytokines and CRP levels in subjects developing toxicities. (A) IFN-γ (IFN-g), (B) IL-10, (C) IL-6, and (D) CRP concentrations increase after infusion of CAR T cells (2 days following ASCT) in all patients. Both IFN-γ and IL-10 increased significantly at day 5 post-ASCT in subjects developing a neurotoxicity plus or minus CRS than in subjects without toxicities (P < .001 and P = .07, respectively). There was a trend for significant increase of IL-6 concentration in subjects with CRS than in subjects without CRS. Increases in CRP levels were similar in subjects with and without toxicities.

Figure 4.

PFS of subjects treated on study.

Figure 5.

Events (progression or death) related to 19-28z CAR T-cell expansion. (A) Persistence in days and (B) peak according to vector copy number per microliter peripheral blood by quantitative PCR.

Figure 6.

Representative progression of DLBCL negative for CD19 surface expression. (A) Core biopsy shows involvement by DLBCL (hematoxylin-and-eosin [H&E] stain). (B) By immunohistochemistry, the neoplastic B cell strongly expresses B-cell lineage marker CD20 with cell-surface pattern (CD20 immunostain). (C) In contrast, CD19 is only weakly expressed with an exclusively cytoplasmic pattern without surface expression (CD19 immunostain). (A-C) Original magnification ×400.

Figure 7.

Immunophenotype of 19-28z CAR T-cell products infused and relationship to events (progression or death) and toxicity. Open circles represent data points for each subjects’ graft products’ immunophenotype proportion. (A) Events. Subjects whose infused CAR T cells were composed of a greater percentage of naive-like (CD45RA⁺, CCR7⁺) cells were more likely to experience an event for both CD4⁺ (P = .02) and CD8⁺ (P = .04) CAR⁺ subsets. No significant difference was seen in other immunophenotypic subsets: central memory (CD45RA⁻, CCR7⁺), effector memory (CD45RA⁻, CCR7⁻), and effector (CD45RA⁺, CCR7⁻) T cells. (B) Toxicity. No significant differences were seen in any immunophenotypic subsets of the 19-28z CAR T graft product between subjects who did or did not experience toxicity.