Multi-institutional Prospective Research of Expanded Multi-antigen Specifically Oriented Lymphocytes for the Treatment of VEry High Risk Hematopoietic Malignancies (RESOLVE)

Multi-institutional Prospective Research of Expanded Multi-antigen Specifically Oriented Lymphocytes for the Treatment of VEry High Risk Hematopoietic Malignancies

Multi-institutional Prospective Phase I Research of Expanded Multi-antigen Specifically Oriented Lymphocytes for the Treatment of VEry High Risk Hematopoietic Malignancies

This Phase I dose-escalation trial is designed to evaluate the safety of administering rapidly -generated tumor multi-antigen associated -specific cytotoxic T lymphocytes, to HSCT recipients (Arm A) or future HSCT recipients (Arm B) for the treatment of high-risk or relapsed or refractory hematopoietic malignancies. In addition to safety, this study will also evaluate if event-free survival (EFS) is improved with TAA-T administration at six months after HSCT for patients with high risk AML and MDS (Arm C).

This Phase I dose-escalation trial is designed to evaluate the safety of administering rapidly -generated tumor multi-antigen associated -specific cytotoxic T lymphocytes, to HSCT recipients (Arm A) or future HSCT recipients (Arm B) for the treatment of high-risk or relapsed or refractory hematopoietic malignancies. In addition to safety, this study will also evaluate if event-free survival (EFS) is improved with TAA-T administration at six months after HSCT for patients with high risk AML and MDS (Arm C). Patients with evidence of high-risk or relapsed or persistent hematopoietic malignancies (for example but not limited to: acute leukemia, lymphoma, chronic myeloid leukemia (CML), chronic myelomonocytic leukemia (CMML), myelodysplastic syndrome (MDS)) will be eligible for this study. Patients will be enrolled at two time points (for differing indications) in three arms (Arm A - post HSCT, Arm B- pre HSCT and Arm C for patients with AML or MDS to prevent relapse post HSCT). Because patients with persistent malignancy prior to transplantation have an extremely poor prognosis, these patients will be eligible to receive TAA-T before and/or after allogeneic hematopoietic stem cell transplantation (HSCT). Arm B patients will receive autologous TAA-T following a cycle of conventional chemotherapy in an effort to decrease the burden of disease prior to HSCT. Patients with persistent disease or high risk for relapse will be eligible to receive planned infusion of allogeneic TAA-T after HSCT (given the very high likelihood of relapse and poor outcome) on Arm A. Patients with high risk AML and MDS who have undergone allo-HSCT and are in a hematologic remission will enroll under Arm C. In all populations, we will utilize our established protocol for the manufacture of tumor multi-antigen associated specific cytotoxic T lymphocytes. Peripheral blood mononuclear cells will be exposed to antigen presenting cells pulsed with peptides to tumor antigens (PRAME, WT1, Survivin) in a cytokine milieu favorable to T cell expansion/activation, inducing selective expansion of T cells targeted to kill tumor cells. Patients would be monitored for the development of toxicity. In patients with disease at the time of TAA-T infusion, efficacy would be evaluated as a secondary endpoint using standard criteria. Exploratory investigational analyses would include monitoring of cytokine and cellular milieu pre- and post- TAA-T infusion and in vitro characterization of the host tumor, donor lymphocyte product, and TAA-T product. For Arm A Patients (post-HSCT): TAA-T will be infused any time after neutrophil engraftment post-HSCT or day 30, whichever comes first. For Arm B Patients (pre-HSCT): TAA-T will be infused any time > 7 days after previous therapy for relapsed disease. For Arm C Patients (post-HSCT): TAA-T will be infused any time after neutrophil engraftment post-HSCT or day 30, whichever comes first at dose level 4 . Infusions will be within first 5 months post-HSCT. Five different dosing levels will be evaluated. Two to four patients will be evaluated on each dosing schedule (see below). This protocol is designed as a phase I dose-escalation study. Patients will be enrolled to one of the following dosing levels: Dose Level One: 5 x 106 cells/m2 Dose Level Two: 1 x 107 cells/m2 Dose Level Three: 2 x 107 cells/m2 Dose Level Four: 4 x 107 cells/m2 Dose Level Five: 1 x 108 cells/m2 (ONLY applicable to Arm A patients) Arm C patients will ONLY be enrolled at: Dose Level Four (4 x 107 cells/m2) Each patient will receive at least one infusion according to the enrolled dose level, where the expected volume of infusion is 1 to 10 cc. Patients will receive cells either because: of prior refractory disease and/or high risk for relapse and/or detectable disease at the time of infusion. Arm A and Arm B patients will use the dose escalation strategy described above. Ideally, patients should not receive other systemic antineoplastic agents for at least 45 days after infusion of TAA-T (for purposes of evaluation), although such treatment may be added if deemed critical for patient care by the attending physician and not under IND. Pediatric patients will be enrolled only after the safety analysis has been completed and is acceptable for 2 adult patients in Arm A and B. Arm C will enroll pediatric and adult patients. Arm C patients (post HSCT): T cells will be infused any time after neutrophil engraftment post-HSCT or day 30, whichever comes first, but within first 5 months after HSCT on Dose level 4 (4x10e7/m2). If patients with active disease (defined as hematologic relapse or minimal residual disease positive (MRD+) any time after allo-HSCT for Arm A and defined as hematologic relapse or MRD+ at the time of TAA-T infusion for Arm B and defined as MRD+ at the time of TAA-T infusion for Arm C) do not have ≥ grade 3 toxicity that is possibly, probably, or definitely attributed to TAA-T infusion and fail to rapidly progress with disease requiring urgent therapy, patients may receive a subsequent TAA-T cell dose (infusion #2). A subsequent dose (infusion #2) will also be available for those patients who have stable disease or a mixed, partial, or complete response (including continued complete response) by the International Working Group (IWG) criteria (see section 4.2.1) at the evaluation after the first TAA-T infusion. Patients who have received at least 2 infusions of TAA-T are eligible to receive up to 6 additional doses (infusion #3 to #8) of TAA-T at monthly intervals each of which will consist of the same cell number as their enrolled dose level. Patients will not be able to receive additional doses until the initial safety profile is completed at 28 days following the second infusion. Notably, these doses will be identical to the treated dose for this patient (i.e. no subsequent dose escalation). Patients would then receive additional doses starting greater than 28 days from second infusion and be treated at the same dose level as he/she has previously received.

For Arm A Patients (post-HSCT): TAA-T will be infused any time after neutrophil engraftment post-HSCT or day 30, whichever comes first. For Arm B Patients (pre-HSCT): TAA-T will be infused any time > 7 days after previous therapy for relapsed disease. For Arm C Patients (post-HSCT): TAA-T will be infused any time after neutrophil engraftment post-HSCT or day 30, whichever comes first. All infusions will be within 5 months post-HSCT. Five different dosing levels will be evaluated. Two to four patients will be evaluated on each dosing schedule (see below). This protocol is designed as a phase I dose-escalation study. Dose Level One: 5 x 106 cells/m2 Dose Level Two: 1 x 107 cells/m2 Dose Level Three: 2 x 107 cells/m2 Dose Level Four: 4 x 107 cells/m2 Dose Level Five: 1 x 108 cells/m2 (ONLY applicable to Arm A patients) Arm C patients will ONLY be enrolled at: Dose Level Four (4 x 107 cells/m2)

TAA-T may be generated from donors or recipients and will be tested for specificity to 3 tumor antigens commonly found in hematological malignancies (WT1, PRAME, and SURVIVIN,). The goal of this cell infusion will be to initiate an immune response to residual leukemia or lymphoma that includes multiple antigens and may prevent tumor evasion (through decreased expression of a single antigen).

Safety including acute GVHD grades III-IV within 45 days of the last dose of TAA-T or grades 3-5 infusion-related adverse events within 45 days of the last TAA-T dose or grades 4-5 non-hematological attributable adverse events within 45 days of the last TAA-T dose and that are not due to the pre-existing infection or the original malignancy or pre-existing co-morbidities as defined by the NCI Common Terminology Criteria for Adverse Events (CTCAE), Version 4.03. For Arm C, the primary endpoint is to determine if event-free survival (EFS) is improved with TAA-T administration at six months after HSCT for patients with high risk acute myeloid leukemia and MDS.

- To determine the number of patients who respond to tumor associated antigen lymphocytes (TAA-T) for the treatment for relapsed/refractory hematopoietic malignancies as defined by those who achieve CR, PR, MR, or SD following cell infusion and evaluate if this was associated with in vivo persistence of TAA-T.

To determine the incidence and severity of acute and/or chronic GVHD in patients treated with TAA-T and compare this to historical controls

- Event free and overall survival at 1 year for patients enrolled under Arm A and B. Event-free survival at 6 months and overall survival at 1 year after HSCT for patients enrolled under Arm C.

Recipient procurement Inclusion criteria: Aged 6 months to 80 years Received prior or anticipated myeloablative or non-myeloablative allogeneic hematopoietic stem cell transplant Patients (Arm A) who have undergone allo-HSCT with high risk or relapse or residual/recurrent disease (see below) OR patients (Arm B) with high risk or relapsed/refractory disease (> 2 regimens with greater than M1 marrow or persistent HD) with anticipated allo-HSCT: Acute lymphoblastic leukemia (ALL), Acute myeloid leukemia (AML), Ambiguous lineage leukemia or lymphoma, Chronic Myelogenous leukemia (CML), CMML, MDS: Evidence of active leukemia or lymphoma disease by flow cytometry, morphology, or cytogenetic evaluation within the marrow or extramedullary sites. Hodgkin's Lymphoma that has failed or are intolerant of Brentuximab, Non-Hodgkin Lymphoma (NHL) including Grey Zone Lymphoma, Anaplastic large cell lymphoma (ALCL), and mantle cell lymphoma: Evidence of lymphoma by morphology, Positron Emission Tomography (PET)/ Computed tomography (CT) uptake in a site of previous disease in the absence of other etiologies. ARM C only includes patients with high risk AML and MDS who have received an allo-HSCT and have not had hematologic relapse of disease. Karnofsky/Lansky score of ≥ 50 Agree to use contraceptive measures during study protocol participation (when age appropriate) Patient or parent/guardian capable of providing informed consent. T cell chimerism > 94% if collected from recipient of allo-HSCT (performed within the last 6 months) If the product is procured from the recipient in the autologous (Arm B) setting, the absolute lymphocyte count should be greater than or equal to 600 for procurement. Please note: If a patient has already undergone an allogeneic HSCT, it is NOT allowed to generate TAA-T from patient blood collected post-HSCT under Arm A or C Recipient Procurement Exclusion Criteria: Patients with uncontrolled infections Current evidence of GVHD > grade 2 or bronchiolitis obliterans syndrome, sclerotic GVHD, or serositis Pregnancy or lactating (female of childbearing potential) Recipient Inclusion criteria for initial TAA-T administration and for subsequent infusions Patients (Arm A) who have undergone allo-HSCT with high risk or relapse or residual/recurrent disease (see below) OR patients (Arm B) with high risk or relapsed/refractory disease (> 2 regimens with greater than M1 marrow or persistent HD) with anticipated allo-HSCT: o Acute lymphoblastic leukemia (ALL), Acute myeloid leukemia (AML), Ambiguous lineage leukemia or lymphoma, Chronic Myelogenous leukemia (CML), CMML, MDS: Evidence of active leukemia or lymphoma disease by flow cytometry, morphology, or cytogenetic evaluation within the marrow or extramedullary sites. o Hodgkin's Lymphoma that has failed or are intolerant of Brentuximab, NHL including Grey Zone Lymphoma, ALCL, and mantle cell lymphoma: Evidence of lymphoma by morphology, PET/CT uptake in a site of previous disease in the absence of other etiologies. o ARM C only includes patients with high risk AML and MDS who have received an allo-HSCT and have not had hematologic relapse of disease. Steroids less than 0.5 mg/kg/day prednisone or equivalent. Karnofsky/Lansky score of ≥ 50. Bilirubin < 2.5 mg/dL, AST/ALT <5x upper limit of normal, Serum creatinine < 1.0 or 2x the upper limit of normal (whichever is higher). Pulse oximetry of > 90% on room air. Absolute neutrophil count > 250/ µL (may be supported with Granulocyte colony-stimulating factor (GCSF)). Agree to use contraceptive measures during study protocol participation (when age appropriate). Patient or parent/guardian capable of providing informed consent. LVEF > 50% or LVSF > 27% (performed within the last 6 months) if history of TBI >500 cGy for arm A and B. Total chimerism > 50%; or if cancer cells preclude this, donor T cell chimerism > 50% (performed within the last 6 months). Recipient Exclusion criteria for initial and subsequent TAA-T infusions Patients who received ATG, Campath, or other T cell immunosuppressive monoclonal antibodies within 28 days prior to TAA-T infusion. No investigational therapies (under IND, not extensively studied in the current clinical context) within 28 days prior to TAA-T infusion. For allogeneic HSCT recipients PD-1 inhibitors or other T cell activating agents will be excluded. For Arm B, if the patient has tolerated these agents without autoimmunity, these may be continued with the TAA-T infusion. Uncontrolled infections Active Bronchiolitis obliterans syndrome, sclerotic GVHD, or serositis Current evidence of GVHD > grade 2 for Arm A and B; Active GVHD of any grade is exclusion for arm C patients. Pregnancy or lactating (female of childbearing potential)

Kinoshita H, Cooke KR, Grant M, Stanojevic M, Cruz CR, Keller M, Fortiz MF, Hoq F, Lang H, Barrett AJ, Liang H, Tanna J, Zhang N, Shibli A, Datar A, Fulton K, Kukadiya D, Zhang A, Williams KM, Dave H, Dome JS, Jacobsohn D, Hanley PJ, Jones RJ, Bollard CM. Outcome of donor-derived TAA-T cell therapy in patients with high-risk or relapsed acute leukemia post allogeneic BMT. Blood Adv. 2022 Apr 26;6(8):2520-2534. doi: 10.1182/bloodadvances.2021006831.