ALBERT

Description: Abstract The diagnosis and management of drug‐induced liver injury (DILI) remains a challenge in clinical trials in drug development. The qualification of emerging biomarkers capable of predicting DILI soon after the initiation of treatment, differentiating DILI from underlying liver disease, identifying the causal entity, and assigning appropriate treatment options after DILI is diagnosed are needed. Qualification efforts have been hindered by lack of properly stored and consented biospecimens that are linked to clinical data relevant to a specific context of use. Recommendations are made for biospecimen collection procedures, with the focus on clinic trials, and for specific emerging biomarkers to focus qualification efforts. This article is protected by copyright. All rights reserved.

Description: Abstract 578 Autologous stem cell transplantation (ASCT) for multiple myeloma (MM) offers a unique setting to explore the role of immunotherapeutic strategies in eradicating residual disease. A fundamental challenge to developing an effective anti-tumor immune response is overcoming the immunosuppressive milieu by which tumor cells evade host immunity. Key elements contributing to tumor-mediated immune suppression are the increased presence of regulatory T cells in patients with malignancy, and upregulation of the PD-1/PDL1 pathway. Tumor expression of PD-L1 promotes T cell tolerance by binding PD-1 on activated T cells and suppressing their capacity to secrete stimulatory cytokines. In addition, the PD-1/PDL-1 pathway has been shown to inhibit T cell-mediated lysis of tumor cells, potentially preventing a clinically meaningful immunologic response to tumor vaccines. We are conducting a clinical trial in which patients with MM are treated with an anti-PD1 antibody (CT-011) alone (Cohort 1) and in combination with a dendritic cell/myeloma fusion cell vaccine (Cohort 2) following ASCT. To date, 27 patients have been enrolled into Cohort 1, in which patients receive three infusions of CT-011 at doses of 3mg/kg given at 6 week intervals beginning 1–3 months following ASCT. Mean age of the patients is 57 years; 61% are male. 11 patients have received at least two infusions of CT-011. The remaining patients are undergoing pre-transplant therapy/transplant. CT-011 has been well tolerated, with possibly related adverse events consisting of transient grade 1–2 leukopenia, diarrhea, fatigue, arthralgia, rash, and peri-orbital edema. One patient developed grade 3 neutropenia, which resolved after two days without growth factor. Immunologic response was determined by quantifying circulating tumor reactive T cells prior to each dose of CT-011 and at 1, 3, 6 months following the last infusion, as defined by the percentage of T cells expressing IFNg in response to ex vivo exposure to autologous tumor lysate. 4 patients have completed 6 months of follow up after the third dose of CT-011, and are evaluable for immune response. CT-011 therapy was associated with the dramatic expansion of myeloma specific T cells. Mean percentage of circulating tumor reactive CD4+ and CD8+ T cells increased from 1.5 and 1.96 respectively prior to the first infusion of CT-011, to 4.26 and 8.28 respectively 1 month following the third infusion. As determined by tetramer staining in the subset of patients who are HLA A2.1, infusion of CT-011 resulted in a mean 9 fold expansion of T cells specific to the MUC1 antigen, which is aberrantly expressed by myeloma cells. Notably, immunologic response to CT-011 persists at 6 months following completion of therapy. Clinical response, as determined by time to disease progression, will be determined with longer follow up, as the median time from transplant is presently 8 months. We are initiating enrollment to Cohort 2, in which patients will be vaccinated with an autologous DC/myeloma fusion vaccine 1 week prior to each dose of CT-011. These data demonstrate that CT-011 results in the expansion of tumor reactive lymphocytes in the early post-transplant period, providing an ideal platform for combination with a tumor vaccine. Disclosures: Rosenblatt: CureTech Ltd.: Research Funding. Schickler:CurTech Ltd.: Employment, Research Funding. Rotem-Yehudar:CureTech Ltd: Employment, Research Funding. Avigan:CureTech Ltd: Research Funding.

Description: Introduction Our group has pioneered a personalized vaccine in which patient-derived acute myeloid leukemia (AML) cells are fused with autologous dendritic cells (DC/AML fusion), presenting a broad array of leukemia associated antigens with DC mediated costimulation. In a clinical trial of AML patients who were vaccinated after chemotherapy-induced remission, 71% remained free of disease at median follow up of 57 months. We sought to identify factors associated with durable remission after vaccination using genomic analysis of the bone marrow microenvironment including single cell RNA-seq and TCR clonal diversity analysis. Methods Banked bone marrow samples both prior to and 1 month post-vaccination were selected from patients who maintained long disease remission for greater than 5 years and those who had early relapse. FFPE marrow core biopsy samples (N=10) were the source for gene expression analysis. NEBNext ultra II directional library prep kit and Illumina NextSeq 500/550 system were used to generate reliable high quality RNA sequencing data. Differentially expressed genes were identified by p-value (≤0.01) and fold change (≥2) using Linear Models for Microarray (Limma) approach. Ingenuity Pathways IPA 9.0 was then used to define pathways and upstream regulators. Flash frozen samples (N=4) were analyzed by RNAseq at the single cell level using a standard 10X genomics approach with cell cluster annotation performed with Single Cell Wizard software. Banked peripheral blood was used to evaluate TCR diversity with Takara SMART-Seq next-generation sequencing to amplify variable regions of TCR- α/β subunits. Results Heatmaps depict significant differential gene expression in bone marrow biopsies both pre- and post-vaccination in patients who remained in long-term remission (responders) compared to those who relapsed (non-responders). Prior to vaccination there was modest upregulation of immune activation pathways including IL-7, IL-17A as well as inhibition of TGF-b in responders, suggesting a role of the micro-environment in modulating response. Significantly upregulated pathways in responders after vaccination (p value

Description: Introduction: Multiple myeloma (MM) is associated with profound and widespread disarray of both the adaptive and innate arms of the immune system including loss of effector T cell function, humoral immune deficiency, and natural killer (NK) cell immunity. This immunosuppressive milieu is crucial to promoting disease progression. Standard treatment options (immunomodulators (IMIDs) and proteosome inhibitors, radiation, and high-dose corticosteroids) offer modest benefit, but also contribute to further immune suppression. Little is known regarding the mechanisms by which immune dysfunction and immunoevasion occur. Our group has characterized an important role for the programmed death receptor-1 (PD-1) / PD-L1 signaling axis in these processes. MDV9300 (formerly CT-011 / Pidilizumab) is a novel IgG1 humanized monoclonal antibody (mAb) that modulates the immune response through interaction with PD-1. Lenalidomide (Len) an IMID exerts efficacy in MM in part through enhancement of NK cell versus MM effect - an effect likely mediated through T cell production of interleukin (IL)-2. In our in-vitro study, pretreatment of NK cells with MDV9300 with or without Len enhanced immune complex formation between NK cells and MM tumor targets and also augmented NK cell activation and cytotoxicity against MM. We sought to determine the safety, tolerability and any early signs of efficacy in relapsed or refractory MM patients using MDV9300 in combination with Len. Methods: In the phase I portion, the primary endpoint is to determine the maximum tolerated dose (MTD) of the combination. Key eligibility criteria are relapsed or refractory disease but not progressed on Len 25 mg; ≥2 prior lines of therapy, absolute neutrophil count ≥ 1000/µL; Platelets ≥60,000/µL; and creatinine clearance of ≥ 40ml/min. Patients are treated with escalating doses of MDV9300 and Len utilizing a 3x3 escalation design (Table 1). If stable disease is the best response after 4 cycles, patients have the option of adding dexamethasone (20-40mg weekly). Len dose may be modified independently of MDV9300. Patients can receive a maximum of 12 cycles of therapy. Results: Twelve patients are evaluable to date. The median age was 68.5 (range 49-82) and the median time from diagnosis 4.98 years (range 1.54-12.62). At study entry, 67% had high risk cytogenetics (del 17p, complex karyotype, gain 1q) and the median number of prior treatment lines was 2 (range 2-11). 100% of patients had received prior Len, bortezomib and Dex, 50% alkylating agents (cyclophosphamide, oral melphalan, bendamustine), 75% autologous stem cell transplant, 25% pomalidomide and 33% carfilzomib. MDV9300 infusion has been well tolerated with only one grade 2 infusion related toxicity with sore throat. The patient received hydrocortisone with no further reaction observed. Grade 3/4 Anemia, neutropenia, and thrombocytopenia attributable to therapy have been seen in 25%, 23%, and 34% of patients, respectively. Other common grade 2-3 therapy related adverse events are fatigue (50%), anorexia (17%), and hypophosphatemia (17%). There has been no grade 3 or higher infection and no worsening of neuropathy from baseline. Len dose was reduced in 3 patients (25%) and increased in one. There has been no dose reduction in MDV9300. Dex 20 mg or less was added in 2 patients for muscle cramps and 〈 PR after 3 cycles. To date 7 patients are off therapy; 1 due to grade 3 fatigue and 6 due to disease progression. Five patients continue on therapy at respective 12, 11, 9, 5 and 3 months. Responses to date have been 3 Very good partial response,1 partial response, 2 minimal response and 2 stable disease. Conclusion: The combination of steroid sparing MDV9300 and Len regimen has demonstrated an acceptable toxicity profile to date with evidence of anti-myeloma activity. This is the first reported combination anti-PD-1 based immune therapy for MM. Updated results will be presented at the meeting including the MTD dose for phase II. Table 1. MDV9300- mg/kg Intravenously given on day 3 every 28 days Lenalidomide- mg orally days 1-21 every 28 days DLT Evaluable DLTs Cohort 1 1.5 15 6 Grade 3 fatigue. Cohort extended to 6 Cohort 2 3 15 3 none Cohort 3 3 25 3 none Cohort 4 6 25 0 Acknowledgments: Drug has been provided by Medivation; The study is sponsored by the American Cancer Society Disclosures No relevant conflicts of interest to declare.

Description: Abstract 1216 Poster Board I-238 Background: PD-1 (Program Death-1), an immune inhibitory receptor and its ligands PD-L1 and PD-L2, participate in peripheral tolerance and play a key role in immune suppression and evasion mechanisms in cancer and chronic infectious diseases. PD-1 inhibits activation signals and functions as a pro-apoptotic receptor in effector lymphocytes, and consequently regulates the extent and duration of specific adaptive and innate immune responses. CT-011, a humanized antibody, blocks the function of PD-1, resulting in increased activities of T and NK cells in vitro and in enhanced tumor immunity in experimental tumor models. At the molecular level, the antibody enhances PI3K-mediated survival and trafficking signals, attenuates cell death in effector/memory (CD4+CD45RO+) cells, and enhances trafficking in response to Stromal Cell-derived Factor-1 (SDF-1). We hypothesized that CT-011 would enhance effector/memory cells in patients with DLBCL after AuSCT and delay recurrence. Methods: We treated 41 patients (pts) with DLBCL from 30-90 days after AuSCT with CT-011 and now report data on effector/memory and memory lymphocytes in the first 30 pts. CT-011 was given at a dose of 1.5mg/kg for 3 doses, 6 weeks apart. The primary endpoint was to determine the proportion of patients who have not relapsed or died within 18 months following autologous PBSCT, and it is too early for that analysis. Our secondary endpoint was to measure the number of effector /memory and memory lymphocytes before and after treatment, and those data are the subject of this report. Results: Flow cytometry analyses (Table) on pre (baseline: BL) and post-treatment blood samples from the first 30 pts enrolled show elevated levels of specific effector/memory and memory CD4+ T lymphocytes following treatment with CT-011; the median absolute number (ABS) of effector/memory CD4+CD45RO+CD62L-CCR7- cells was increased by +49% from BL (p

Description: Abstract 1862 Poster Board I-887 Background: Biotest AG (Dreieich, Germany) is developing the immunoconjugate BT062, which comprises the anti-CD138 chimerized MAb (nBT062) and the cytotoxic agent maytansinoid (DM4). Once bound to CD138 on a target cell, the conjugate is internalized and releases DM4. At present, CD138 represents one of the most reliable target antigens for identification of multiple myeloma (MM) cells and has been reported to be a highly sensitive and specific diagnostic marker of MM. Preclinical investigations demonstrated significant in vitro and in vivo anti-MM activity of BT062, providing the rationale for the conduct of clinical trials (Ikeda et al., 2009). Objectives: To determine the maximum tolerated dose (MTD), the dose-limiting toxicities (DLTs), pharmacokinetics (PK) and anti-MM activity of increasing doses of BT062 on a repeated single dose schedule once every three weeks in relapsed or relapsed/refractory MM. Clinical response was assessed as per the international working group criteria (Durie et al., 2006). Methods: This is a prospective, open label, dose-escalation multicenter study. Patients aged ≥ 18 years with relapsed or relapsed/refractory MM who have failed previous treatments including an immunomodulating agent and a proteasome inhibitor were eligible to participate. Patients with clinical response (or no evidence of progressive disease) and without unacceptable toxicities were eligible for further treatment cycles. Patients are enrolled in cohorts of 3 at each dose level, with DLT in the first cycle triggering cohort expansion. Results: To date 20 patients have been treated with BT062 at 7 dose levels ranging from 10 mg/m2 to 200 mg/m2. Maximum administered dose has not been defined to date with continued enrollment at 200 mg/m2 dose. None of the patients treated experienced serious hypersensitivity reactions or humoral responses (HAHA) against BT062. The most frequently reported adverse events to date cover primarily events expected for the underlying disease. Nevertheless, a few adverse events have also been observed involving skin and mucosa (tissues of epithelial origin with CD138 expressing cells). No grade 4 toxicity has been reported. Preliminary PK results indicate an unusual rapid clearance from plasma in the early elimination phase, followed by a generally normal terminal elimination phase at dose levels up to 120 mg/m2, whereas a more typical clearance profile was observed for all 3 patients at the 160 mg/m2 dose. Interestingly, even in phase I study decreased urine M-Protein or serum FLC levels have been observed in 2 patients. One of these patients showed a decrease in urine M-Protein by more than 50% after administration of 8 repeated low doses. At a high dose level another patient without detectable M-Protein levels, showed a decrease of serum FLC by more than 50% after having received the second dose of BT062. Furthermore, evidence of clinical benefit has been observed in at least 6 patients with early stabilization of M-protein levels (and light-chain burden) in serum and /or urine. Conclusion: Development of a monoclonal antibody in MM remains an important therapeutic option and BT062 is an exciting possibility. Preliminary data from this phase I study, demonstrate an acceptable toxicity profile of BT062 in the clinics. Even in phase I study, evidence of clinical activity is observed. These encouraging results and the unique PK observed support investigation of a more frequent dosing regimen for optimizing anti-MM responses. Updated data on safety, PK and efficacy of BT062 from this clinical trial will be presented at the meeting. Disclosures: Jagannath: Millennium: Honoraria, Membership on an entity's Board of Directors or advisory committees; Merck: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Avigan:Genzyme: Consultancy, Research Funding; Celgene: Research Funding. Lutz:Immunogen, Inc.: Employment. Haeder:Biotest AG: Employment. Ruehle:Biotest AG: Employment. Uherek:Biotest AG: Employment. Wartenberg-Demand:Biotest AG: Employment. Munshi:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Millennium: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Anderson:Celgene: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Millennium: Consultancy, Research Funding; Biotest AG: Consultancy, Research Funding.

Description: Introduction Umbilical cord blood (UCB) transplantation yields survival comparable to adult stem cell transplantation, but there is significant variability among UCB products, in large part because of differences in processing conditions from collection to cryopreservation at cord banks. While impact of processing conditions on the actual UCB product has been reported, there is a little information regarding impact on patient-level outcomes. We report a retrospective exploratory analysis of processing performed at cord banks prior to freezing of UCB units and the impact on clinical outcomes such as engraftment, cord dominance, transplant-related mortality (TRM) and overall survival (OS) in 133 UCB recipients. Methods All adult recipients of unmanipulated double UCB transplantation (dUCBT) for hematologic malignancy from 2003 to 2011 at the 3 Harvard Cancer Center sites (Dana-Farber Cancer Institute, Massachusetts General Hospital, and Beth Israel Deaconess Medical Center) were included. All UCB units were thawed and washed prior to infusion. Multivariate analyses controlled for prognostic factors including age, malignancy, conditioning intensity, degree of HLA matching, presence of anti-HLA antibodies, order of cord infusion, TNC/kg, and CD34+/kg infused. Time to engraftment and treatment-related mortality were analyzed in the competing risks regression setting and survival was analyzed using proportional hazards models. Results 98 recipients underwent reduced-intensity conditioning, primarily fludarabine, melphalan and anti-thymocyte globulin. 35 underwent myeloablative conditioning, primarily cyclophosphamide and total body irradiation. Of the 48 banks contributing cords to this study, 42% employed simple cryopreservation and 23% employed plasma/volume reduction only, at some point during operation. These 2 methods were considered “RBC replete”. Of the 34 banks sharing their current practices, simple cryopreservation is no longer practiced by any; 12% practice plasma/volume reduction alone. 88% of the banks now employ RBC depletion, of which 67% use hydroxyethyl starch for RBC sedimentation and 67% use automated processing systems. Engraftment – Neutrophil and platelet engraftment were not impacted by RBC depletion, sedimentation with hydroxyethyl starch, automated processing, HLA matching or CD34+/kg dose in multivariate analyses. An anti-HLA antibody against one or more cords (p

Description: Background: Bortezomib (VELCADE®, Bz) is approved for the treatment of patients (pts) with multiple myeloma (MM). Lenalidomide (Revlimid®, Len) plus dexamethasone (Dex) is approved for the treatment of relapsed MM pts following ≥1 prior therapy. Len/Bz±Dex is active and well tolerated in relapsed/refractory MM, and Len/Dex and Bz/Dex are active in front-line MM. The aims of this phase l/ll study were to determine the maximum tolerated dose of Len/Bz/Dex (RVD) and to assess safety and efficacy in previously untreated MM pts. Methods: Pts received Len 15–25 mg on days 1–14, Bz 1.0–1.3 mg/m2 on days 1, 4, 8, 11, and Dex 40/20 mg (cycles 1–4/5–8) on days 1, 2, 4, 5, 8, 9, 11, 12, for up to eight 21-day cycles, initially at four planned dose levels (Len/Bz: 15/1.0, 15/1.3, 20/1.3, 25/1.3). Dose-escalation proceeded (three-pt cohorts) depending on dose-limiting toxicities (DLTs; Grade (G) ≥3 non-hematologic toxicity; G4 thrombocytopenia with platelets 1 occasion despite transfusion support; G4 neutropenia for 〉5 days and/or resulting in neutropenic fever; inability to receive cycle 2/day 1 dose due to drug-related toxicity). Based on safety data, dose level 4M (Len/Bz 25/1.3) was added with a reduced Dex (20/10 mg) starting dose. Pts with G≥2 peripheral neuropathy (PNY) were excluded. Responses were assessed by modified European Group for Blood and Marrow Transplantation (EBMT) and Uniform Criteria. Pts with at least partial response (≥PR) could proceed to autologous stem cell transplant (ASCT) after ≥4 cycles. Results: 68 pts have been enrolled to date: 33 in phase l, including 17 pts at the maximum planned dose (MPD, dose level 4M) and 35 in phase ll (at MPD). Data are available for 66 pts (median age 58 yrs, 55% men, 67% IgG MM, 50% with ISS stage II/III). Pts have received a median of 10 cycles; 46 have completed all 8 cycles, 39 have discontinued/completed therapy. Two DLTs of G3 hyperglycemia due to high-dose Dex were seen at dose level 4. Dose reductions in cycle 2 and beyond have occurred in overall/dose levels 1–4 for: Len 16/8 pts, Bz 23/8 pts, and Dex 19/15 pts. Toxicities to date have been manageable, including all G3/4 hematological toxicities (3–15%), G3 hypophosphatemia (8%) and deep vein thrombosis/pulmonary embolism (5%, with daily aspirin), with no G4 PNY, and no treatment-related mortality. The overall response rate (ORR; ≥ PR) is 98%, including 71% ≥ VGPR and 36% CR/nCR; at MPD, ORR is 100%. Efficacy was independent of baseline cytogenetics or ISS stage (Table). ORR and ≥ VGPR rates were similar regardless of the absence or presence of deletion 13q or translocation 4;14; ORR rates ranged from 86% to 100% and ≥ VGPR rates ranged from 57% to 75%. Pts from all three ISS categories achieved ORR ranging from 97% to 100% and ≥ VGPR ranging from 51% to 80%; of note, the 10 pts with ISS stage III disease had an ORR of 100% and ≥ VGPR rate of 80%. Median stem cell collection in 21/23 pts was 6.2 × 106 CD34+ cells/kg after a median of 6 cycles of therapy; 15 pts have proceeded to ASCT, with the transplant course in each case reported as unremarkable. Two of 23 pts (9%) have had difficulty with mobilization. After a median follow-up of 8 months, median time to progression, progression-free survival, and overall survival have not been reached. Conclusions: RVD produces high quality responses and is well tolerated in newly diagnosed MM pts, regardless of their cytogenetic status or ISS stage. MPD has been reached at Len 25 mg, Bz 1.3 mg/m2, and Dex 20 mg, with phase ll enrollment now complete and 100% ORR reported at the MPD. Stem cell mobilization has been successful in almost all pts, with transplant course in pts otherwise unremarkable. Updated efficacy and ASCT data will be presented at the meeting. Responses by cytogenetic status (normal, abnormal [deletion 13q or t(4;14)]), and ISS stage Normal Abnormal No Del 13q With Del 13q No t(4;14) With t(4;14) * pts with available data n* (63) 39 24 52 7 49 10 ≥ PR 100% 96% 100% 86% 98% 100% P 0.381 0.119 1.00 ≥ VGPR 69% 79% 75% 57% 73% 70% P 0.560 0.375 1.00 ISS I ISS II ISS III n* (64) 33 21 10 ≥ PR 97% 100% 100% P 0.385 ≥ VGPR 51% 57% 80% P 0.421