Angela Shen

Chimeric Antigen Receptor T Cells for Sustained Remissions in Leukemia

BACKGROUND Relapsed acute lymphoblastic leukemia (ALL) is difficult to treat despite the availability of aggressive therapies. Chimeric antigen receptor-modified T cells targeting CD19 may overcome many limitations of conventional therapies and induce remission in patients with refractory disease. METHODS We infused autologous T cells transduced with a CD19-directed chimeric antigen receptor (CTL019) lentiviral vector in patients with relapsed or refractory ALL at doses of 0.76×10(6) to 20.6×10(6) CTL019 cells per kilogram of body weight. Patients were monitored for a response, toxic effects, and the expansion and persistence of circulating CTL019 T cells. RESULTS A total of 30 children and adults received CTL019. Complete remission was achieved in 27 patients (90%), including 2 patients with blinatumomab-refractory disease and 15 who had undergone stem-cell transplantation. CTL019 cells proliferated in vivo and were detectable in the blood, bone marrow, and cerebrospinal fluid of patients who had a response. Sustained remission was achieved with a 6-month event-free survival rate of 67% (95% confidence interval [CI], 51 to 88) and an overall survival rate of 78% (95% CI, 65 to 95). At 6 months, the probability that a patient would have persistence of CTL019 was 68% (95% CI, 50 to 92) and the probability that a patient would have relapse-free B-cell aplasia was 73% (95% CI, 57 to 94). All the patients had the cytokine-release syndrome. Severe cytokine-release syndrome, which developed in 27% of the patients, was associated with a higher disease burden before infusion and was effectively treated with the anti-interleukin-6 receptor antibody tocilizumab. CONCLUSIONS Chimeric antigen receptor-modified T-cell therapy against CD19 was effective in treating relapsed and refractory ALL. CTL019 was associated with a high remission rate, even among patients for whom stem-cell transplantation had failed, and durable remissions up to 24 months were observed. (Funded by Novartis and others; CART19 ClinicalTrials.gov numbers, NCT01626495 and NCT01029366.).

Chimeric antigen receptor T cells persist and induce sustained remissions in relapsed refractory chronic lymphocytic leukemia

CAR T cells persist and sustain remissions in advanced chronic lymphocytic leukemia. CAR T cells for the long haul Immunotherapy is one of the most promising avenues of cancer therapy, with the potential to induce sustained remissions in patients with refractory disease. Studies with chimeric antigen receptor (CAR)–modified T cells have paved the way in patients with relapsed and refractory chronic lymphocytic leukemia. Porter et al. now report the mature results from their initial CAR T cell trial. CAR T cell persistence correlated with clinical responses, and these cells were functional up to 4 years after treatment. No patient who achieved complete remission relapsed, and no minimal residual disease was detected, suggesting that in a subset of patients, CAR T cells may drive disease eradication. Patients with multiply relapsed or refractory chronic lymphocytic leukemia (CLL) have a poor prognosis. Chimeric antigen receptor (CAR)–modified T cells targeting CD19 have the potential to improve on the low complete response rates with conventional therapies by inducing sustained remissions in patients with refractory B cell malignancies. We previously reported preliminary results on three patients with refractory CLL. We report the mature results from our initial trial using CAR-modified T cells to treat 14 patients with relapsed and refractory CLL. Autologous T cells transduced with a CD19-directed CAR (CTL019) lentiviral vector were infused into patients with relapsed/refractory CLL at doses of 0.14 × 108 to 11 × 108 CTL019 cells (median, 1.6 × 108 cells). Patients were monitored for toxicity, response, expansion, and persistence of circulating CTL019 T cells. The overall response rate in these heavily pretreated CLL patients was 8 of 14 (57%), with 4 complete remissions (CR) and 4 partial remissions (PR). The in vivo expansion of the CAR T cells correlated with clinical responses, and the CAR T cells persisted and remained functional beyond 4 years in the first two patients achieving CR. No patient in CR has relapsed. All responding patients developed B cell aplasia and experienced cytokine release syndrome, coincident with T cell proliferation. Minimal residual disease was not detectable in patients who achieved CR, suggesting that disease eradication may be possible in some patients with advanced CLL.

Panobinostat in Patients With Relapsed/Refractory Hodgkin's Lymphoma After Autologous Stem-Cell Transplantation: Results of a Phase II Study

PURPOSE Hodgkins lymphoma (HL) has no standard of care for patients who are relapsed or refractory to autologous stem-cell transplantation (ASCT). This phase II study examined safety and activity of panobinostat in this population. PATIENTS AND METHODS Panobinostat 40 mg was administered orally three times per week. The primary end point was objective response rate (ORR) based on investigator assessment of radiologic imaging. Secondary end points included ORR by independent central review, time to response (TTR), duration of response (DOR), progression-free survival (PFS), overall survival, and safety. Exploratory biomarker analyses were performed. RESULTS The 129 treated patients (median age, 32 years; range, 18 to 75 years) were heavily pretreated with a median of four (range, two to seven) prior systemic regimens, and 41% did not respond to the regimen immediately preceding panobinostat. Tumor reductions occurred in 96 patients (74%). Objective response was achieved by 35 patients (27%), including 30 (23%) partial responses and five (4%) complete responses. The median TTR was 2.3 months, median DOR was 6.9 months, and median PFS was 6.1 months. The estimated 1-year overall survival rate was 78%. Common nonhematologic adverse events (AEs)-diarrhea, nausea, vomiting, and fatigue-were generally grade 1 and 2. Most common grade 3 and 4 hematologic AEs-thrombocytopenia, anemia, and neutropenia-were manageable. Early reductions in thymus and activation-regulated chemokine were observed in patients achieving complete or partial response. CONCLUSION In the largest, prospective, multicenter, international trial conducted in heavily pretreated patients with HL who relapsed or were refractory to ASCT, panobinostat monotherapy demonstrated antitumor activity, resulting in durable responses.

A single dose of peripherally infused EGFRvIII-directed CAR T cells mediates antigen loss and induces adaptive resistance in patients with recurrent glioblastoma

A trial of autologous T cells redirected to a specific mutation in glioblastoma patients illustrates mechanisms of resistance. Speeding toward CAR T cell therapy for glioblastoma Chimeric antigen receptor (CAR) T cells have been successfully implemented for treating leukemia and are now being investigated for solid tumors. O’Rourke et al. conducted a phase 1 safety study of autologous CAR T cells targeted to EGFR variant III in glioblastoma patients. Treatment seemed to be well tolerated, which is critical because other CAR T cell products have been implicated in devastating central nervous system complications. Of the 10 patients enrolled, 7 had surgical intervention, allowing for some analysis of the tumors and T cells in patients’ brains. The results of this trial indicate that CAR T cell therapy is a viable option for treating glioblastoma. We conducted a first-in-human study of intravenous delivery of a single dose of autologous T cells redirected to the epidermal growth factor receptor variant III (EGFRvIII) mutation by a chimeric antigen receptor (CAR). We report our findings on the first 10 recurrent glioblastoma (GBM) patients treated. We found that manufacturing and infusion of CAR-modified T cell (CART)–EGFRvIII cells are feasible and safe, without evidence of off-tumor toxicity or cytokine release syndrome. One patient has had residual stable disease for over 18 months of follow-up. All patients demonstrated detectable transient expansion of CART-EGFRvIII cells in peripheral blood. Seven patients had post–CART-EGFRvIII surgical intervention, which allowed for tissue-specific analysis of CART-EGFRvIII trafficking to the tumor, phenotyping of tumor-infiltrating T cells and the tumor microenvironment in situ, and analysis of post-therapy EGFRvIII target antigen expression. Imaging findings after CART immunotherapy were complex to interpret, further reinforcing the need for pathologic sampling in infused patients. We found trafficking of CART-EGFRvIII cells to regions of active GBM, with antigen decrease in five of these seven patients. In situ evaluation of the tumor environment demonstrated increased and robust expression of inhibitory molecules and infiltration by regulatory T cells after CART-EGFRvIII infusion, compared to pre–CART-EGFRvIII infusion tumor specimens. Our initial experience with CAR T cells in recurrent GBM suggests that although intravenous infusion results in on-target activity in the brain, overcoming the adaptive changes in the local tumor microenvironment and addressing the antigen heterogeneity may improve the efficacy of EGFRvIII-directed strategies in GBM.

Immune regulatory effects of panobinostat in patients with Hodgkin lymphoma through modulation of serum cytokine levels and T-cell PD1 expression

Immune regulatory effects of panobinostat in patients with Hodgkin lymphoma through modulation of serum cytokine levels and T-cell PD1 expression

Abstract LB-083: Phase I study of T cells redirected to EGFRvIII with a chimeric antigen receptor in patients with EGFRvIII+ glioblastoma

We initiated a Phase I study of intravenous delivery of autologous T cells re-directed to the EGFR variant III mutation by means of a lentiviral vector encoding a chimeric antigen receptor (CAR). Patients with recurrent glioblastoma (GBM) have their tumors screened for the presence of the EGFRvIII mutation by a next-generation sequencing based assay. Eligible patients undergo leukapheresis for collection of autologous T cells, which are genetically modified ex vivo to express the EGFRvIII CAR, expanded, and then cryopreserved for infusion. We report results on the nine patients we have treated. We targeted a challenging subset of GBM patients, with multi-focal residual, progressive disease refractory to standard and experimental therapies, including temozolomide, bevacizumab, and radiation. To date, we have found that infusion of 1-5×10⁁8 CART-EGFRvIII cells is feasible to manufacture and infusion is safe, without evidence of off-tumor toxicity or cross-reactivity to wild type EGFR. No clinical or laboratory signs of systemic cytokine release syndrome have been observed, though elevations in serum IL-6 occur concurrently with CART-EGFRvIII expansion in the peripheral blood. One patient developed non-convulsive status epilepticus nine days after CART-EGFRvIII infusion, which resolved with standard treatment and anti-cytokine therapy. All patients have had significant expansion of CART-EGFRvIII cells between 7-10 days post-infusion, as measured by flow cytometry and quantitative PCR in peripheral blood samples. Five patients have undergone surgical resection of tumor between 6-120 days after infusion, and pathologic evaluation has demonstrated infiltration of activated CAR T cells, recruitment of new T cells (as assessed by next generation T cell receptor deep sequencing), and specific EGFRvIII target antigen loss in GBM cells in some cases. These findings provide evidence that CART-EGFRvIII cells are safe, without evidence of off-target toxicity or cytokine release syndrome, and are immunologically active. The data also suggest a mechanism of antigen editing by activated CART-EGFRvIII cells that track to specific EGFRvIII GBM cells. Citation Format: Donald M. O’Rourke, MacLean P. Nasrallah, Jennifer Morrissette, Jan J. Melenhorst, Simon F. Lacey, Keith Mansfield, Maria Martinez-Lage, Arati Desai, Steven Brem, Eileen Maloney, Suyash Mohan, Sumei Wang, Gaurav Verma, Jean-Marc Navenot, Angela Shen, Zhaohui Zheng, Bruce L. Levine, Hideho Okada, Carl H. June, Marcela V. Maus. Phase I study of T cells redirected to EGFRvIII with a chimeric antigen receptor in patients with EGFRvIII+ glioblastoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-083.

Abstract PR06: T cells engineered with a chimeric antigen receptor (CAR) targeting CD19 (CTL019) produce complete responses and long-term persistence without GVHD in children with relapsed, refractory ALL

Background: CARs combine a single chain variable fragment (scFv) of an antibody with intracellular signaling domains into a single chimeric protein. We previously reported on CTL019 cells expressing a CAR recognizing CD19 combined with the CD137 and CD3 zeta intracellular activation domain, including 1 sustained CR in a patient with ALL (Grupp, et al. NEJM 2013). We now report on outcomes and longer follow up from our pilot study treating 16 children with relapsed, refractory ALL. Methods: T cells were lentivirally transduced with a CAR composed of anti-CD19 scFv/4-1BB/CD3ζ, activated/expanded ex-vivo with anti-CD3/anti-CD28 beads, and then infused into pts with relapsed or refractory CD19+ ALL. 13/16 pts received lymphodepleting chemotherapy the week prior to CTL019 infusion. The targeted T cell dose range was 10 7 to 10 8 cells/kg with a transduction efficiency (TE) of 11-45%. 11 pts had relapsed ALL after a prior allogeneic SCT. T cells were collected from the pt, regardless of prior SCT status, though all pts had to be 6 mos s/p SCT with no GVHD or GVHD treatment. Results: 16 children median age 9.5 y (5-22y) with CD19+ ALL were treated. One child had T cell ALL aberrantly expressing CD19. 14/16 pts had active disease or +MRD after chemotherapy on the day prior to CTL019 cell infusion, while 2 were MRD(-). A median of 4x10 6 CTL019 cells/kg (1.1-18x10 6 /kg) were infused over 1-3 days. There were no infusional toxicities >grade 2, although 3 pts developed fevers within 24 hrs of infusion and did not receive planned subsequent infusions of CTL019 cells. 13 patients (81%) achieved a CR, including the patient with CD19+ T ALL, 3 did not respond. 10/16 evaluable pts as of August 28, 2013 have ongoing BM CR with median follow up 3.4 mo (1.2-16 mo). Three patients with a CR at 1 month have subsequently relapsed, 1 with CD19(-) disease. All responding pts developed some degree of delayed cytokine release syndrome (CRS) at the time of peak T cell expansion, and a subset experienced transient hypotension and hypoxia. Treatment with tocilizumab, an anti IL6-receptor antagonist, reversed the CRS related hemodynamic or respiratory instability seen, though corticosteroids were used concurrently in some patients. No GVHD was observed, and cells collected from SCT recipients were generally of 100% donor origin. Persistence of CTL019 cells detected by flow cytometry and/or QPCR in pts with ongoing responses continued for 1-15 months after infusion, resulting in complete B cell aplasia during the period of CTL019 persistence. Pts have been treated with IVIg without any unusual infectious complications. One child who entered a CR subsequently developed MDS with a new trisomy 8 in ALL remission, and 1 child developed a single leukemia cutis lesion at 6 mo, still BM MRD(-). Conclusions: CTL019 cells are T cells genetically engineered to express an anti-CD19 scFv coupled to CD3ζ signaling and 4-1BB costimulatory domains that can undergo robust in-vivo expansion and can persist for 15 mo or longer in pts with relapsed ALL. CTL019 therapy is associated with a significant CRS that responds rapidly to IL-6-targeted anticytokine treatment. This approach has promise as a salvage therapy for patients who relapse after allo-SCT, and collection of tolerized cells from the recipient appears to have a low risk of GVHD. CTL019 cells can induce potent and durable responses for patients with relapsed/refractory ALL. This abstract is also presented as Poster B69. Citation Format: Stephan A. Grupp, Shannon Maude, Richard Aplenc, David M. Barrett, Michael Kalos, Bruce Levine, Manuel Lichtman, Susan Rheingold, Angela Shen, Christine Strait, David Teachey, Patricia A. Wood, Carl June. T cells engineered with a chimeric antigen receptor (CAR) targeting CD19 (CTL019) produce complete responses and long-term persistence without GVHD in children with relapsed, refractory ALL. [abstract]. In: Proceedings of the AACR Special Conference on Pediatric Cancer at the Crossroads: Translating Discovery into Improved Outcomes; Nov 3-6, 2013; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2013;74(20 Suppl):Abstract nr PR06.