ALBERT

Description: A single-center trial of CD19 directed, lentiviral transduced chimeric antigen receptor (CAR) T cells (CTL019) for relapsed and refractory (r/r) B-ALL pediatric patients showed rates of CR 〉90% with prolonged CAR T cell persistence/CR without further therapy in the majority of patients infused (Maude NEJM 2014). We report here the feasibility, safety and efficacy of the first multicenter global pivotal registration CAR T cell trial. Features of this trial include: i) the first trial in which industry-manufactured cells were provided to all patients; ii) enrollment across 25 centers in the US, EU, Canada, Australia, and Japan; iii) successful transfer and manufacturing of cells in a global supply chain; and iv) successful implementation of cytokine release syndrome (CRS) management across a global trial. All patients had CD19 positive B-ALL with morphologic marrow tumor involvement at registration (〉5% blasts), and were either primary refractory; chemo-refractory after first relapse, relapsed after second line therapy; or ineligible for allogeneic SCT. CTL019 was manufactured from patient PBMC under GMP conditions in the US, at a centralized "sponsor-owned" manufacturing facility, and supplied to all sites. The primary endpoint of overall remission rate (CR+CRi) within 3 months and secondary endpoints (EFS, DOR, OS and safety) were assessed by an independent review committee. Based on preliminary data as of March 2016, 57 patients were enrolled. There were 3 manufacturing failures (5%), 5 patients were not infused due to death or adverse events (9%), and 15 patients were pending infusion at the data cut off. Following fludarabine/cyclophosphamide lymphodepleting chemotherapy in the majority of the patients, 34 patients (median age 11 [3-23], 50% with prior HSCT) were infused with a single dose of CTL019 at a median dose of 2.9 x106 transduced CTL019 cells/kg (0.2 to 4). Among 29 patients reaching D28 prior to the data cutoff, 83% (24/29) achieved CR or CRi by local investigator assessment, all of which were MRD-negative. Two early deaths occurred prior to initial disease assessment, one due to disease progression and one due to intracranial hemorrhage. Two patients did not respond. One patient was in CR by BM at D28, but CSF was not assessed, therefore this patient was classified as "incomplete" assessment. Safety was managed by a protocol-specified CRS algorithm with no cases of refractory CRS. Using the Penn CRS grading scale, 82% of patients experienced CRS, with 7 grade 3 (21%) and 8 grade 4 (24%) events. 44% patients with CRS required anti-cytokine therapy; all received tocilizumab with or without other anti-cytokine therapy, with complete resolution of CRS. Besides CRS, the most common grade 3 and 4 non-hematologic AEs were febrile neutropenia (29%), increased bilirubin (21%), increased AST (21%), and hypotension (21%). 21% of patients experienced grade 3 or 4 neuropsychiatric events including confusion, delirium, encephalopathy, agitation and seizure; no cerebral edema was reported. CTL019 in vivo cellular kinetics by qPCR demonstrated transgene persistence in blood in responding patients at and beyond 6 months. Overall exposure (AUC 0-28d) and maximal expansion (Cmax) of CTL019 DNA measured by qPCR was higher in responding compared with non-responding patients. In summary, this pivotal global study in pediatric and young adult patients with r/r B-ALL receiving CTL019, confirms a high level of efficacy and a similar safety profile to that shown in the prior single center experience. Safety was effectively and reproducibly managed by appropriately trained investigators. The study has completed accrual. At the meeting, updated data from a planned formal interim analysis including safety, efficacy (primary and selected secondary endpoints), cellular kinetics, and impact of anti-cytokine therapy will be presented for more than 50 patients infused at 25 global sites. Disclosures Grupp: Jazz Pharmaceuticals: Consultancy; Novartis: Consultancy, Research Funding; Pfizer: Consultancy. Laetsch:Novartis: Consultancy; Loxo Oncology: Consultancy. Bittencourt:Seattle Genetics: Consultancy; Jazz Pharmaceuticals: Consultancy, Other: Educational Grant. Maude:Novartis: Consultancy. Myers:Novartis Pharmaceuticals: Consultancy. Rives:Novartis: Consultancy; Jazz Pharma: Consultancy. Nemecek:Medac, GmbH: Research Funding; Novartis: Consultancy; National Marrow Donor Program: Membership on an entity's Board of Directors or advisory committees. Schlis:Novartis: Honoraria. Martin:Jazz Pharmaceuticals: Other: One time discussion panel; Novartis: Other: Support of clinical trials. Bader:Medac: Consultancy, Research Funding; Riemser: Research Funding; Neovii Biotech: Research Funding; Servier: Consultancy, Honoraria; Novartis: Consultancy, Honoraria. Peters:Novartis: Consultancy; Jazz: Speakers Bureau; Amgen: Consultancy; Pfizer: Consultancy; Medac: Consultancy. Biondi:Novartis: Membership on an entity's Board of Directors or advisory committees, Other: Advisory Board; Cellgene: Other: Advisory Board; BMS: Membership on an entity's Board of Directors or advisory committees. Baruchel:Servier: Consultancy; Novartis: Consultancy; Celgene: Consultancy; Jazz: Consultancy; Baxalta: Research Funding. June:University of Pennsylvania: Patents & Royalties; Johnson & Johnson: Research Funding; Celldex: Consultancy, Equity Ownership; Pfizer: Honoraria; Immune Design: Consultancy, Equity Ownership; Novartis: Honoraria, Patents & Royalties: Immunology, Research Funding; Tmunity: Equity Ownership, Other: Founder, stockholder . Sen:Novartis: Employment. Zhang:Novartis: Employment. Thudium:Novartis: Employment. Wood:Novartis Pharmaceuticals: Employment, Other: Stock. Taran:Novartis: Employment. Pulsipher:Chimerix: Consultancy; Jazz Pharmaceutical: Consultancy; Novartis: Consultancy, Other: Study Steering Committee; Medac: Other: Housing support for conference.

Description: Viral infection or reactivation remains a major cause of morbidity and mortality after allogeneic stem cell transplantation. We now show that infusions of single cytotoxic T lymphocyte (CTL) lines (5 × 106-1.35 × 108 cells/m2) with specificity for 2 commonly detected viruses, Epstein-Barr virus (EBV) and adenovirus, can be safely administered to pediatric transplantation recipients receiving partially human leukocyte antigen–matched and haploidentical stem cell grafts (n = 13), without inducing graft-versus-host disease. The EBV-specific component of the CTLs expanded in vivo and persisted for more than 12 weeks, but the adenovirus-specific component only expanded in vivo in the presence of concomitant adenoviral infection. Nevertheless, adenovirus-specific T cells could be detected for at least 8 weeks in peripheral blood, even in CTL recipients without viral infection, provided the adenovirus-specific component of their circulating lymphocytes was first expanded by exposure to adenoviral antigens ex vivo. After infusion, none of these 13 high-risk recipients developed EBV-associated lymphoproliferative disease, while 2 of the subjects had resolution of their adenoviral disease. Hence, bispecific CTLs containing both EBV- and adenovirus-specific T cells can safely reconstitute an antigen responsive “memory” population of CTLs after human leukocyte antigen–mismatched stem cell transplantation and may provide antiviral activity. This trial was registered at www.clinicaltrials.gov as #NCT00590083.

Description: Adenoviruses remain a major cause of mortality and morbidity in hematopoietic stem cell transplant (HSCT) recipients. To date, no effective anti-adenoviral treatment is available, presenting a potential role for adoptive T cell therapy, as an increased risk of infection may be correlated with lack of endogenous T cell immunity. Therefore the goal of this project was to evaluate the use of adenovirus-specific cytotoxic T lymphocyte (CTL) lines for the prophylaxis and treatment of adenoviral infections post-HSCT. CTLs are initiated by stimulation with donor-derived mononuclear cells transduced with a recombinant adenovirus type 5 vector pseudotyped with a type 35 fiber (MOI 200 virus particles (vp) per cell). Responder cells are expanded by weekly restimulation with autologous EBV-transformed B lymphoblastoid cell lines (LCL) transduced with the same vector using an MOI of 500 vp. Nine of the 11 CTL lines manufactured for clinical use were predominantly CD4+ (range 12–95%), but all had a CD8+ component (range 3.5–79%). In chromium release assays, all CTL lines showed specific killing of both adenovirus and EBV antigen-bearing target cells. Recognition of adenovirus and EBV targets was not significantly different; at 20:1 effector:target ratio there was 18.5 ± 14% specific lysis of adenovirus targets and 23 ± 15% lysis of EBV targets while uninfected recipient target cells were not lysed (1.5 ± 2%). We identified the hexon as the immunodominant target antigen in the CTL lines. To test the hypothesis that these polyclonal CD4+ and CD8+ hexon-specific T cells can provide protection against adenovirus infections in HSCT recipients, we administered donor-derived bi-virus-specific CTL lines to pediatric recipients of allogeneic stem cell transplant. So far, we have treated 7 patients in this phase I dose escalation study (using the continual reassessment model); 2 patients on dose level 1 (5x106/m2), 2 on dose level 2 (1.5x107/m2) and 2 on dose level 3 (4.5x107/m2). Of 6 patients who received CTL as prophylaxis, all remain negative for adenovirus and EBV and there were no adverse events attributable to CTL infusion. Post-infusion, samples for immune monitoring were collected for at least 3 months and analyzed by pentamer and IFN-g ELISPOT assays in batches to minimize inter-assay variablility. An increase in the frequency of EBV-specific T cells could be detected in the blood by 2 weeks post infusion in all evaluated patients, likely due to the presence of this latent virus in all patients. However, there was no significant rise in the adenovirus-specific T cell frequency post-infusion. The seventh patient received the bi-virus-specific CTL at a dose of 5x106/m2 as treatment for adenovirus disease. This patient had adenoviral pneumonia requiring ventilatory support. Following the CTL infusion the patient made a dramatic clinical recovery, was weaned off mechanical ventilation, and discharged a month after the infusion. In contrast to the prophylaxis group, this patient had a substantial rise in adenovirus-specific T cells detected in the peripheral blood by 4 weeks post-CTL infusion, which coincided with his clinical recovery and clearance of the virus from the tracheal aspirate, suggesting that the infused cells were effective in vivo. Adoptive immunotherapy for adenovirus appears to be safe but expansion of adenovirus-specific CTL in vivo may require the presence of antigen to stimulate the infused cells.