RESUMO
BACKGROUND: Chimeric antigen receptor (CAR) modified T cells targeting CD19 have shown activity in case series of patients with acute and chronic lymphocytic leukaemia and B-cell lymphomas, but feasibility, toxicity, and response rates of consecutively enrolled patients treated with a consistent regimen and assessed on an intention-to-treat basis have not been reported. We aimed to define feasibility, toxicity, maximum tolerated dose, response rate, and biological correlates of response in children and young adults with refractory B-cell malignancies treated with CD19-CAR T cells. METHODS: This phase 1, dose-escalation trial consecutively enrolled children and young adults (aged 1-30 years) with relapsed or refractory acute lymphoblastic leukaemia or non-Hodgkin lymphoma. Autologous T cells were engineered via an 11-day manufacturing process to express a CD19-CAR incorporating an anti-CD19 single-chain variable fragment plus TCR zeta and CD28 signalling domains. All patients received fludarabine and cyclophosphamide before a single infusion of CD19-CAR T cells. Using a standard 3â+â3 design to establish the maximum tolerated dose, patients received either 1â×â10(6) CAR-transduced T cells per kg (dose 1), 3â×â10(6) CAR-transduced T cells per kg (dose 2), or the entire CAR T-cell product if sufficient numbers of cells to meet the assigned dose were not generated. After the dose-escalation phase, an expansion cohort was treated at the maximum tolerated dose. The trial is registered with ClinicalTrials.gov, number NCT01593696. FINDINGS: Between July 2, 2012, and June 20, 2014, 21 patients (including eight who had previously undergone allogeneic haematopoietic stem-cell transplantation) were enrolled and infused with CD19-CAR T cells. 19 received the prescribed dose of CD19-CAR T cells, whereas the assigned dose concentration could not be generated for two patients (90% feasible). All patients enrolled were assessed for response. The maximum tolerated dose was defined as 1â×â10(6) CD19-CAR T cells per kg. All toxicities were fully reversible, with the most severe being grade 4 cytokine release syndrome that occurred in three (14%) of 21 patients (95% CI 3·0-36·3). The most common non-haematological grade 3 adverse events were fever (nine [43%] of 21 patients), hypokalaemia (nine [43%] of 21 patients), fever and neutropenia (eight [38%] of 21 patients), and cytokine release syndrome (three [14%) of 21 patients). INTERPRETATION: CD19-CAR T cell therapy is feasible, safe, and mediates potent anti-leukaemic activity in children and young adults with chemotherapy-resistant B-precursor acute lymphoblastic leukaemia. All toxicities were reversible and prolonged B-cell aplasia did not occur. FUNDING: National Institutes of Health Intramural funds and St Baldrick's Foundation.
Assuntos
Antígenos CD19 , Terapia Baseada em Transplante de Células e Tecidos , Linfoma não Hodgkin/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Receptores de Antígenos de Linfócitos T , Linfócitos T/transplante , Adolescente , Adulto , Criança , Pré-Escolar , Quimera , Estudos de Coortes , Estudos de Viabilidade , Feminino , Humanos , Lactente , Masculino , Linfócitos T/imunologia , Resultado do Tratamento , Adulto JovemRESUMO
PURPOSE: Patients with metastatic or relapsed pediatric sarcomas receive cytotoxic regimens that induce high remission rates associated with profound lymphocyte depletion, but ultimately few survive long term. We administered adjuvant immunotherapy to patients with metastatic and recurrent pediatric sarcomas in an effort to improve outcomes. EXPERIMENTAL DESIGN: Mononuclear cells were collected via apheresis, and tumor lysate was acquired via percutaneous biopsy at enrollment. Participants received standard antineoplastic therapy, followed by autologous lymphocytes, tumor lysate/keyhole limpet hemocyanin-pulsed dendritic cell vaccinations ± recombinant human IL7. Primary outcomes were toxicity and vaccine responses. Secondary outcomes were immune reconstitution, event-free survival, and overall survival (OS). RESULTS: Forty-three patients enrolled and 29 received immunotherapy. The regimen was well tolerated. Intent-to-treat analysis demonstrated 5-year OS of 51% with significant differences based upon histologic group (63% vs. 0% for Ewing/rhabdomyosarcoma vs. other sarcomas) and response to standard therapy (74% no residual disease vs. 0% residual disease). Five-year intent-to-treat OS of patients with newly diagnosed metastatic Ewing/rhabdomyosarcoma was 77%, higher than previously reported in this population and higher than observed in a similar group treated with an earlier adjuvant immunotherapy regimen (25% 5-year OS). T-cell responses to autologous tumor lysate were identified in 62% of immunotherapy recipients, and survival was higher in those patients (73% 5-year OS with vs. 37% without immune response, P = 0.017). Immune reconstitution, measured by CD4 count recovery, was significantly enhanced in subjects treated with recombinant human IL7. CONCLUSIONS: Adjuvant immunotherapy may improve survival in patients with metastatic pediatric sarcoma. Clin Cancer Res; 22(13); 3182-91. ©2016 AACR.
Assuntos
Células Dendríticas/transplante , Fatores Imunológicos/uso terapêutico , Imunoterapia Adotiva/métodos , Interleucina-7/uso terapêutico , Rabdomiossarcoma/terapia , Sarcoma de Ewing/terapia , Linfócitos T/transplante , Adolescente , Adulto , Quimioterapia Adjuvante/métodos , Criança , Pré-Escolar , Terapia Combinada , Células Dendríticas/imunologia , Intervalo Livre de Doença , Feminino , Humanos , Leucaférese , Masculino , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/prevenção & controle , Rabdomiossarcoma/imunologia , Rabdomiossarcoma/patologia , Sarcoma de Ewing/imunologia , Sarcoma de Ewing/patologia , Linfócitos T/imunologia , Adulto JovemRESUMO
Natural killer (NK) cells can mediate potent antitumor effects, but factors regulating the efficiency of tumor lysis remain unclear. Studies in allogeneic stem cell transplantation highlight an important role for killer cell immunoglobulin-like receptor (KIR) mismatch in overcoming human leukocyte antigen-mediated inhibitory signals. However, other activating and inhibitory signals also modulate tumor lysis by NK cells. We used rhIL15 and artificial antigen presenting cells expressing CD137L and IL15Rα to activate and expand peripheral blood NK cells (CD137L/IL15 NK) up to 1000-fold in 3 weeks. Compared with resting NK cells, CD137L/IL15 NK cells show modest increases in KIR expression and substantial increases in NKG2D, tumor necrosis factor-related apoptosis-inducing ligand, and natural cytotoxicity receptors (NCRs: NKp30, NKp44, NKp46). Compared with resting NK cells, CD137L/IL15 NK cells mediate enhanced cytotoxicity against allogeneic and autologous tumors and KIR signaling did not substantially inhibit cytotoxicity. Rather, tumor lysis by CD137L/IL15 activated NK cells was predominantly driven by NCR signaling as blockade of NCRs dramatically diminished the lysis of a wide array of tumor targets. Furthermore, tumor lysis by CD137L/IL15 NK cells was tightly linked to NCR expression levels that peaked on day 8 to 10 after NK activation, and cytotoxicity diminished on subsequent days as NCR expression declined. We conclude that KIR mismatch is not a prerequisite for tumor killing by CD137L/IL15 NK cells and that NCR expression provides a biomarker for predicting potency of CD137L/IL15 NK cells in studies of NK cell-based immunotherapy.