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T cells modified to express a chimeric antigen receptor (CAR) targeting CD19 can induce potent and sustained responses in children with relapsed/refractory acute lymphoblastic leukemia (ALL). The durability of remission is related to the length of time the CAR T cells persist. Efforts to understand differences in persistence have focused on the CAR construct, in particular the costimulatory signaling module of the chimeric receptor. We previously reported a robust intent-to-treat product manufacturing success rate and remission induction rate in children and young adults with recurrent/refractory B-ALL using the SCRI-CAR19v1 product, a second-generation CD19-specific CAR with 4-1BB costimulation coexpressed with the EGFRt cell-surface tag (NCT02028455). Following completion of the phase I study, two changes to CAR T-cell manufacturing were introduced: switching the T-cell activation reagent and omitting midculture EGFRt immunomagnetic selection. We tested the modified manufacturing process and resulting product, designated SCRI-CAR19v2, in a cohort of 21 subjects on the phase II arm of the trial. Here, we describe the unanticipated enhancement in product performance resulting in prolonged persistence and B-cell aplasia and improved leukemia-free survival with SCRI-CAR19v2 as compared with SCRI-CAR19v1.

T cells modified to express a chimeric antigen receptor (CAR) targeting CD19 can induce potent and sustained responses in children with relapsed/refractory acute lymphoblastic leukemia (ALL). The durability of remission is related to the length of time the CAR T cells persist. Efforts to understand differences in persistence have focused on the CAR construct, in particular the costimulatory signaling module of the chimeric receptor. We previously reported a robust intent-to-treat product manufacturing success rate and remission induction rate in children and young adults with recurrent/refractory B-ALL using the SCRI-CAR19v1 product, a second-generation CD19-specific CAR with 4-1BB costimulation coexpressed with the EGFRt cell-surface tag (NCT02028455). Following completion of the phase I study, two changes to CAR T-cell manufacturing were introduced: switching the T-cell activation reagent and omitting midculture EGFRt immunomagnetic selection. We tested the modified manufacturing process and resulting product, designated SCRI-CAR19v2, in a cohort of 21 subjects on the phase II arm of the trial. Here, we describe the unanticipated enhancement in product performance resulting in prolonged persistence and B-cell aplasia and improved leukemia-free survival with SCRI-CAR19v2 as compared with SCRI-CAR19v1.

Supplementary Data from Modified Manufacturing Process Modulates CD19CAR T-cell Engraftment Fitness and Leukemia-Free Survival in Pediatric and Young Adult Subjects

The theoretical generalization and experimental confirmation of the features of the progression of myelodysplastic syndrome are presented in the article. The purpose of the study was to identify the available clinical parameters that may be suitable for assessing of the course of MDS and predicting the risk of transformation of this pathology into acute leukemia. The subject of the study was a group of patients with different subtypes of myelodysplastic syndrome according to the FAB classification. The statistical analysis was performed using the application software package STATISTICA for Windows 5.0 and NCSS. Leukemia-free survival was evaluated using the Kaplan-Meier method. To compare survival rates in two groups, the log-rank test and the Cox F-criterion were used. Cox proportional hazard regression was used to determine the most significant independent prognostic factors influencing the survival rate. The obtained results indicate that the process of leukemic transformation of the low and high risk myelodysplastic syndrome is different, confirming the presence of different predictive risk factors for the transformation in these patients. It is statistically confirmed that the main predictors that shorten the leukemia free survival in patients with low-risk myelodysplastic syndrome are the age of patients above 60 years, multilineage dysplasia of bone marrow cells and serum TNF-α level above 10 pg/ml. Instead, in patients with high-risk myelodysplastic syndrome, besides the older age and multilineage dysplasia of bone marrow cells, with a shorter leukemia-free survival are also significantly associated: the presence of thrombocytopenia, increased blasts in bone marrow and the IL-6 concentration above 50 pg/ml. Permanent search for prognostic factors and the development of new, more advanced prognostic scales that could cover not only demographic, laboratory or cytogenetic parameters, but also pathogenetic markers, are not only of scientific but also of a great practical importance, since they provide the opportunity to start therapy in patients with a high probability of transformation on time, thereby increasing the time to progression of the disease, in patients with MDS both low and high risk

Background Autologous stem cell transplantation (ASCT) is a potential consolidation therapy for acute myeloid leukemia (AML). This study was designed to develop a prediction model for leukemia-free survival (LFS) in a cohort of patients with de novo AML treated with ASCT during their first complete remission. Methods This was a registry study of 956 patients reported to the European Society for Blood and Marrow Transplantation. The primary outcome was LFS. Multivariate Cox regression modeling with backward selection was used to select variables for the construction of the nomogram. The nomogram's performance was evaluated with discrimination (the area under the receiver operating characteristic curve [AUC]) and calibration. Results Age and cytogenetic risk (with or without FMS-like tyrosine kinase 3 internal tandem duplication) were predictive of LFS and were used for the construction of the nomogram. Each factor in the nomogram was ascribed points according to its predictive weight. Through the calculation of the total score, the probability of LFS at 1, 3, and 5 years for each patient could be estimated. The discrimination of the nomogram, measured as the AUC, was 0.632 (95% confidence interval [CI], 0.595-0.669), 0.670 (95% CI, 0.635-0.705), and 0.687 (95% CI, 0.650-0.724), respectively. Further validation with bootstrapping showed similar AUCs (0.629 [95% CI, 0.597-0.657], 0.667 [95% CI, 0.633-0.699], and 0.679 [95% CI, 0.647-0.712], respectively), and this suggested that the model was not overfitted. Calibration was excellent. Patients were stratified into 4 incremental 5-year prognostic groups, with the probabilities of LFS and overall survival ranging from 25% to 64% and from 33% to 79%, respectively. Conclusions The Auto-AML nomogram score is a tool integrating individual prognostic factors to provide a probabilistic estimation of LFS after ASCT for patients with AML.

The best stem cell source for T-cell replete human leukocyte antigen (HLA)-haploidentical transplantation with post-transplant cyclophosphamide (PTCy) remains to be determined. In this European Society for Blood and Marrow Transplantation retrospective study, we analyzed the impact of stem cell source on leukemia-free survival (LFS) in adult patients with primary refractory or relapsed acute myeloid leukemia (AML) given grafts from HLA-haploidentical donors with PTCy as graft-versus-host disease (GVHD) prophylaxis. A total of 668 patients (249 bone marrow [BM] and 419 peripheral blood stem cells [PBSC] recipients) met the inclusion criteria. The use of PBSC was associated with a higher incidence of grade II-IV (HR = 1.59, p = .029) and grade III-IV (HR = 2.08, p = .013) acute GVHD. There was a statistical interaction between patient age and the impact of stem cell source for LFS (p < .01). In multivariate Cox models, among patients = 55 years of age, the use of PBSC versus BM was associated with higher non-relapse mortality (NRM) (HR = 1.7, p = .01), lower LFS (HR = 1.37, p = .026) and lower overall survival (HR = 1.33, p = .044). In conclusions, our data suggest that in patients >= 55 years of age with active AML at HLA-haploidentical transplantation, the use of BM instead of PBSC as stem cell source results in lower NRM and better LFS. In contrast among younger patients, the use of PBSC results in at least a comparable LFS.