Autologous lymphapheresis for the production of chimeric antigen receptor T cells.

BACKGROUND: The first step in manufacturing chimeric antigen receptor (CAR) T cells is to collect autologous CD3+ lymphocytes by apheresis. Patients, however, often have leukopenia or have other disease-related complications. We evaluated the feasibility of collecting adequate numbers of CD3+ cells, risk factors for inadequate collections, and the rate of adverse events. STUDY DESIGN AND METHODS: Apheresis lymphocyte collections from patients participating in three CAR T-cell clinical trials were reviewed. Collections were performed on the COBE Spectra by experienced nurses, with the goal of obtaining a minimum of 0.6 × 109 and a target of 2 × 109 CD3+ cells. Preapheresis peripheral blood counts, apheresis parameters, and product cell counts were analyzed. RESULTS: Of the 71 collections, 69 (97%) achieved the minimum and 55 (77%) achieved the target. Before apheresis, the 16 patients with yields below the target had significantly lower proportions and absolute numbers of circulating lymphocytes and CD3+ lymphocytes and higher proportions of circulating blasts and NK cells than those who achieved the target (470 × 106 lymphocytes/L vs. 1340 × 106 lymphocytes/L, p = 0.008; 349 × 106 CD3+ cells/L vs. 914 × 106 CD3+ cells/L, p = 0.001; 17.6% blasts vs. 4.55% blasts, p = 0.029). Enrichment of blasts in the product compared to the peripheral blood occurred in four patients, including the two patients whose collections did not yield the minimum number of CD3+ cells. Apheresis complications occurred in 11 patients (15%) and, with one exception, were easily managed in the apheresis clinic. CONCLUSIONS: In most patients undergoing CAR T-cell therapy, leukapheresis is well tolerated, and adequate numbers of CD3+ lymphocytes are collected.

Donor Lymphocyte Infusion for Relapsed Hematological Malignancies after Unrelated Allogeneic Bone Marrow Transplantation Facilitated by the Japan Marrow Donor Program.

To evaluate the safety and efficacy of donor lymphocyte infusion (DLI), we retrospectively analyzed 414 recipients who received unrelated DLI (UDLI) for the treatment of relapsed hematological malignancy after unrelated bone marrow transplantation (BMT). UDLI was administered for acute myelogenous leukemia (n = 184), myelodysplastic syndrome (n = 69), acute lymphocytic leukemia (n = 57), chronic myelogenous leukemia (CML, n = 36), lymphoid neoplasms (n = 38), adult T cell leukemia/lymphoma (n = 18), and multiple myeloma (n = 12). Sixty-five patients (16%) were in cytogenetic/molecular relapse and 349 (84%) were in hematological relapse after BMT. In total, 266 out of 414 (64%) patients received chemotherapy and/or molecular-targeted agents in combination with UDLI. The median time from BMT to UDLI was 244 days. The median number of infused CD3+ cells was 3.51 × 107/kg. Response and survival rates were evaluated at 100 days after UDLI. Complete response was obtained in 37 (57%) of 65 patients with cytogenetic/molecular relapse and in 69 (20%) of 349 patients with hematological relapse (P < .001). Two hundred forty-seven patients (60%) were alive, whereas 110 (26%) had died because of disease progression, 26 (6%) because of infections, 12 (3%) because of graft-versus-host disease (GVHD), and 13 (3%) because of organ failure. Multivariate analysis identified molecular/cytogenetic relapse, GVHD after UDLI, and CML but not combination with chemotherapy as significant prognostic factors. These results indicate that UDLI may have efficacy in relapsed patients with CML, low tumor burden, or occurrence of GVHD after UDLI.

Safety and efficacy of allogeneic PBSC collection in normal pediatric donors: the pediatric blood and marrow transplant consortium experience (PBMTC) 1996-2003.

The use of peripheral blood stem cells (PBSC) for allogeneic transplants in adults has greatly increased. This trend is reflected in pediatrics, where healthy children increasingly are donating PBSC or donor lymphocyte infusion (DLI) via apheresis for use by ill siblings. There is a potential concern that the risks of PBSC collection may differ for pediatric donors. However, no large studies have assessed safety issues in this population. To address this need, we reviewed 218 (213 PBSC, five DLI) collections in 201 normal pediatric donors (8 months to 17 years, median 11.8 years) at 22 institutions in the Pediatric Blood and Marrow Transplant Consortium. Donors received a median of 4 days of growth factor, and mean collection yield was 9.1 x 10(6) CD34+ cells/kg recipient weight. Younger age, days of apheresis, and male gender predicted increased yield of CD34+ cells/kg donor weight. Growth factor-induced pain was mild and reported in less than 15% of patients. Most donors <20 kg (23/25, 92%) required PRBC priming of the apheresis machine. This experience with over 200 collections demonstrates that PBSC collection is safe in normal pediatric donors and desired CD34 cell yields are easily achieved. Younger children utilize more medical resources and children <20 kg usually require a single blood product exposure.

CD8+ T cell dose affects development of acute graft-vs-host disease following reduced-intensity conditioning allogeneic peripheral blood stem cell transplantation.

OBJECTIVE: Acute graft-vs-host disease (aGVHD) remains an important cause of morbidity after reduced-intensity conditioning (RIC) allogeneic transplantation (allo-SCT). It has been shown that antithymocyte globulin (ATG) dose infused during RIC is a major determinant for the likelihood of developing aGVHD. The ATG modulation on aGVHD is likely related to in vivo T-cell depletion. PATIENTS AND METHODS: We therefore investigated the relationship between the cellular composition of the allograft and clinical outcome in 57 patients who received allogeneic peripheral blood stem cells from HLA-identical siblings following an ATG-based RIC. RESULTS: In a multivariate analysis, the CD8+ T cell dose infused was the only parameter associated with the risk of aGVHD (p=0.031; RR=1.96; 95% CI, 1.1-3.6). When looking at the extremes, patients experiencing grade III-IV aGVHD received a median of 143 x 10(6)/kg CD8+ T cells, while patients without aGVHD received a median of 96 x 10(6)/kg CD8+ T cells (p=0.021). None of the different cell subtypes contained in the allograft was associated with a significant probability of developing chronic GVHD. Patients with grade II aGVHD who received an intermediate dose of CD8+ T cells (median, 111 x 10(6)/kg) had a significantly better overall survival in comparison to patients with grade 0-I or grade III-IV aGVHD (p=0.009). CONCLUSION: In comparison to myeloablative allo-SCT, these results demonstrate that a cautious monitoring of the number of cells infused, at least in the context of ATG-based RIC, may represent an important predictive indicator of early transplant-related events and outcome after RIC allo-SCT.

Donor lymphocyte infusions to treat hematologic malignancies in relapse after allogeneic blood or marrow transplantation.

BACKGROUND: Patients with hematologic malignancies in relapse after allogeneic bone marrow transplantation can be treated by infusing leukocytes from the original stem cell donor. METHODS: The published literature on donor lymphocyte infusion (DLI) was reviewed. RESULTS: DLI induces complete remissions in the majority of patients with chronic myeloid leukemia (CML) in early-stage relapse and in less than 30% of patients with relapsed acute leukemia, myelodysplasia, and multiple myeloma. DLI-induced remissions of chronic phase CML are durable, but as many as half of patients with other diseases ultimately relapse. Complications of DLI include acute and chronic graft-vs-host disease (GVHD) and aplasia, which induce profound immunosuppression and susceptibility to opportunistic infections. There is a strong correlation of GVHD and disease response. CONCLUSIONS: Novel methods of augmenting the antitumor efficacy of DLI and of dissociating the graft-vs-leukemia effect from GVHD are needed. These studies will require an improved understanding of the cellular and molecular mechanisms of alloreactivity and the development of novel agents to control the nature and intensity of the alloimmune response.

T-cell--depleted allogeneic bone marrow transplantation followed by donor lymphocyte infusion in patients with multiple myeloma: induction of graft-versus-myeloma effect.

Previous trials of allogeneic bone marrow transplantation (BMT) in patients with multiple myeloma (MM) have demonstrated high response rates but also high transplantation-related mortality (TRM) and high relapse rates. Exploitation of this strategy remains of interest because donor lymphocyte infusions (DLIs) can induce a potent graft-versus-myeloma (GVM) effect. CD6 T-cell--depleted allogeneic BMT was combined with prophylactic CD4(+) DLI administered 6 to 9 months after BMT in an effort to reduce TRM and to induce a GVM response after BMT. Twenty-four patients with matched sibling donors and chemotherapy-sensitive disease underwent BMT. CD6 T-cell depletion of donor bone marrow was the sole method of graft-versus-host disease (GVHD) prophylaxis. GVHD after BMT was minimal, 1 (4%) grade III and 4 (17%) grade II GVHD. Fourteen patients received DLI, 3 in complete response and 11 with persistent disease after BMT. Significant GVM responses were noted after DLI in 10 patients with persistent disease, resulting in 6 complete responses and 4 partial responses. After DLI, 50% of patients developed acute (> or = II) or extensive chronic GVHD. Two-year estimated overall survival and current progression-free survival (PFS) for all 24 patients is 55% and 42%, respectively. The 14 patients receiving DLI had an improved 2-year current PFS (65%) when compared with a historical cohort of MM patients who underwent CD6-depleted BMT survived 6 months with no GVHD and did not receive DLI (41%) (P =.13). Although this study suggests that prophylactic DLI induces significant GVM responses after allogeneic BMT, only 58% of patients were able to receive DLI despite T-cell--depleted BMT. Therefore, less toxic transplantation strategies are needed to allow a higher proportion of patients to receive DLI and the benefit from the GVM effect after transplantation. (Blood. 2001;98:934-939)

Prophylactic donor lymphocyte infusions after moderately ablative chemotherapy and stem cell transplantation for hematological malignancies: high remission rate among poor prognosis patients at the expense of graft-versus-host disease.

We investigated the use of 'prophylactic' donor lymphocyte infusions (DLI) containing 1 x 107 CD3+ cells, given at 30, 60 and 90 days post-allogeneic blood and marrow transplantation (BMT), following conditioning with fludarabine 30 mg/m(2)/4 days and melphalan 70 mg/m(2)/2 days. GVHD prophylaxis consisted of cyclosporin A (CsA) 2 mg/kg daily with early tapering by day 60. Our goals were the rapid achievement of chimerism and disease control, providing an immunological platform for DLIs to treat refractory patients with hematological malignancies. Twelve heavily pre-treated patients with life expectancy less than 6 months were studied; none were in remission. Diagnoses were AML (n = 4), MDS (n = 1), ALL (n = 3), CML (n = 3) and multiple myeloma (n = 1). Response rate was 75%. Three patients are alive at a median of 450 days (range, 450-540). Two patients are in remission of CML in blast crisis and AML for more than 14 months. Median survival is 116 days (range, 25-648). Six patients received 12 DLIs; three patients developed acute GVHD after the first infusion and were excluded from further DLIs, but no GVHD occurred among patients receiving subsequent DLIs. One patient with CML in blast crisis went into CR after the first DLI. The overall incidence of acute GVHD was 70%. Primary causes of death were infections (n = 3), acute GVHD (n = 3), chronic GVHD (n = 1) and disease relapse (n = 2). We observed high response and chimerism rates at the expense of an excessive incidence of GVHD. DLI given at day +30 post BMT caused GVHD in 50% of the patients, and its role in this setting remains unclear.

A closed culture system for the ex vivo transduction and expansion of human T lymphocytes.

A phase I clinical trial is currently being performed at our institution, with the aim of evaluating the feasibility and toxicity related to the administration of herpes simplex thymidine kinase gene-expressing human primary T lymphocytes following allogeneic hematopoietic stem cell transplantation. The need for safe and standardized preparation conditions for gene-modified cells is crucial. We describe the closed culture system used in the current trial for ex vivo retroviral-mediated gene transfer and transduced cell selection. Cell handling is performed in closed systems using a sterile connection device that avoids opening the culture system. Cell numbers during the production process increased from 93 +/- 16 on day 0 to 440 +/- 92 x 10(6) on day 12 (7.2 +/- 1.4-fold increase) (n = 11). Transduction efficiency before and after G418 resistance-based selection was 13.5 +/- 3.8% and 90.0 +/- 1.4%, respectively. Safety and efficacy testing included a search for replication-competent retrovirus, endotoxins, Mycoplasma, and bacterial contamination (n = 0/9), PCR-DNA, % CD3+ cells (91 +/- 2%), and viability after thawing (82 +/- 3%). Effective working time from day 0 to day 12 is approximately 20 h. The closed system we developed allows for safe and reproducible ex vivo preparation of gene-modified primary T lymphocytes for clinical use.

Overview of a quality assurance/quality control compliance program consistent with FDA regulations and policies for somatic cell and gene therapies: a four year experience.

Somatic cell and gene therapy involve the application of biological technologies to an individual patient through the use of living cells which provide a therapeutic benefit (Aliski, 1991). Various forms of cellular and gene therapies are being developed and evaluated in an increasing number of clinical trials for congenital and acquired disorders. The potential and progress of these therapeutic applications have resulted in an increasing effort by the Food and Drug Administration (FDA) to develop the regulatory framework under which these therapeutic approaches would insure safety and efficacy, the primary mandate of the FDA. Over five years ago Cellcor began to define the parameters, specifications, and conditions relevant to a Quality Assurance/Quality Control (QA/QC) program that has evolved to insure safety and maximize the efficacy of applications of the company's ex vivo technology, autolymphocyte therapy. Autolymphocyte therapy is an outpatient form of somatic cell immunotherapy based upon the infusion of T cells that have been activated ex vivo using a combination of previously generated autologous cytokines and an anti-CD3 monoclonal antibody. We have been able to demonstrate the feasibility for the safe, controlled, and consistent preparation and delivery of a cellular therapy by application of relevant GMP regulations. This presentation reviews aspects of this program and chronicles our experience which at present amounts to over 4400 in fusions for over 700 patients. This program provides a high degree of assurance that a cellular therapy program can be carried out in a multisite mode involving hundreds of patients through the strict adherence to cGMP as set forth in existing regulations.(ABSTRACT TRUNCATED AT 250 WORDS)