Fludarabine Cyclophosphamide Research Articles

Treosulfan-Versus Melphalan-Based Reduced Intensity Conditioning in HLA-Haploidentical Transplantation for Patients ≥ 50 Years with Advanced MDS/AML.

Relapse and regimen-related toxicities remain major challenges in achieving long-term survival, particularly among older patients with high-risk myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML) undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). Previous studies have demonstrated the feasibility of treosulfan-based conditioning, noting stable engraftment and low non-relapse mortality (NRM) in patients undergoing HLA-matched allo-HSCT. However, data on treosulfan-based conditioning in the HLA-haploidentical transplantation (HaploT) setting are limited. We retrospectively compared conditioning with fludarabine-cyclophosphamide (FC)-melphalan (110 mg/m2) and FC-treosulfan (30 g/m2) prior to HaploT using post-transplantation cyclophosphamide (PTCy) in patients with high-risk MDS/AML patients ≥ 50 years, transplanted from 2009-2021 at our institution (n = 80). After balancing patient characteristics by a matched-pair analysis, we identified twenty-one matched pairs. Two-year OS and LFS were similar among the groups (OS 66% and LFS 66%, p = 0.8 and p = 0.57). However, FC-melphalan was associated with a significantly lower probability of relapse compared to FC-treosulfan (0% vs. 24%, p = 0.006), counterbalanced by a higher NRM (33% vs. 10%, p = 0.05). Time to engraftment and incidences of acute and chronic graft-versus-host disease (GvHD) did not differ significantly. In conclusion, HaploT using FC-treosulfan in combination with PTCy in patients aged ≥50 years with MDS/AML appears safe and effective, particularly in advanced disease stages. We confirm the favorable extramedullary toxicity profile, allowing for potential dose intensification to enhance antileukemic activity.

Chronic Lymphocytic Leukemia Therapy Guided by Measurable Residual Disease

BackgroundThe combination of ibrutinib and venetoclax has been shown to improve outcomes in patients with chronic lymphocytic leukemia (CLL) as compared with chemoimmunotherapy. Whether ibrutinib–venetoclax and personalization of treatment duration according to measurable residual disease (MRD) is more effective than fludarabine–cyclophosphamide–rituximab (FCR) is unclear.MethodsIn this phase 3, multicenter, randomized, controlled, open-label platform trial involving patients with untreated CLL, we compared ibrutinib–venetoclax and ibrutinib monotherapy with FCR. In the ibrutinib–venetoclax group, after 2 months of ibrutinib, venetoclax was added for up to 6 years of therapy. The duration of ibrutinib–venetoclax therapy was defined by MRD assessed in peripheral blood and bone marrow and was double the time taken to achieve undetectable MRD. The primary end point was progression-free survival in the ibrutinib–venetoclax group as compared with the FCR group, results that are reported here. Key secondary end points were overall survival, response, MRD, and safety.ResultsA total of 523 patients were randomly assigned to the ibrutinib–venetoclax group or the FCR group. At a median of 43.7 months, disease progression or death had occurred in 12 patients in the ibrutinib–venetoclax group and 75 patients in the FCR group (hazard ratio, 0.13; 95% confidence interval [CI], 0.07 to 0.24; P<0.001). Death occurred in 9 patients in the ibrutinib–venetoclax group and 25 patients in the FCR group (hazard ratio, 0.31; 95% CI, 0.15 to 0.67). At 3 years, 58.0% of the patients in the ibrutinib–venetoclax group had stopped therapy owing to undetectable MRD. After 5 years of ibrutinib–venetoclax therapy, 65.9% of the patients had undetectable MRD in the bone marrow and 92.7% had undetectable MRD in the peripheral blood. The risk of infection was similar in the ibrutinib–venetoclax group and the FCR group. The percentage of patients with cardiac serious adverse events was higher in the ibrutinib–venetoclax group than in the FCR group (10.7% vs. 0.4%).ConclusionsMRD-directed ibrutinib–venetoclax improved progression-free survival as compared with FCR, and results for overall survival also favored ibrutinib–venetoclax. (Funded by Cancer Research UK and others; FLAIR ISRCTN Registry number, ISRCTN01844152; EudraCT number, 2013-001944-76.)

Bendamustine Lymphodepletion (LD) Prior to Idecabtagene Vicleucel (Ide-cel) Is Associated with Inferior Outcomes in Relapsed Refractory Multiple Myeloma (RRMM)

Background Chimeric antigen receptor therapy (CART) has revolutionized the management of RRMM. LD prior to CART cells modulates the immune environment creating optimal conditions for T cell expansion and subsequent efficacy. Fludarabine/cyclophosphamide (FLU/CY) is an effective LD regimen, and its use has been adopted widely prior to CART cells for all indications. Since the safety of FLU/CY is not established in patients with substantial renal impairment and given recent nationwide fludarabine shortage, alternative lymphodepletion strategies have been explored. Bendamustine (BENDA) has been shown to be a safe alternative with equivalent efficacy and reduced toxicity in non-Hodgkin's lymphoma (NHL). While its use has been extrapolated to RRMM, efficacy and long-term outcomes have not been examined. Methods We retrieved and analyzed data on sequential patients (pts) with RRMM treated with commercial Ide-cel at a single institution from its approval in 3/2021 until 5/2023. We captured baseline patient, disease and treatment characteristics. We used IgG (with monoclonal component deducted) and uninvolved FLC as indirect surrogate of CAR-T expansion and on target, off tumor killing of non-malignant plasma cells. We assessed cytokine release syndrome (CRS) and immune effector cell associated neurotoxicity (ICANS) based on the American Society for Transplantation and Cellular Therapy criteria and disease responses using the International Myeloma Working Group response criteria. We graded hematologic toxicity using the Common Terminology Criteria for Adverse Events version 5.0. We compared efficacy between the cohorts using overall response rate (ORR) and progression-free survival (PFS), since overall survival is expected to be affected by choice of subsequent, often experimental therapies. Results We identified 28 pts with RRMM who met the inclusion criteria. Nine pts received alternative LD with BENDA (2 pts - renal dysfunction with creatinine clearance &amp;lt;30ml/min; 7 - fludarabine shortage) and 19 received FLU/CY as LD. Baseline characteristics are summarized in Table. Prior autologous stem cell transplant (ASCT) and prior B cell maturation antigen (BCMA) targeting therapy were more frequent in the FLU/CY cohort. Median absolute lymphocyte count (measured in 10^3/ cmm) prior to LD chemotherapy was similar in both cohorts (0.85 in BENDA vs 0.80 in FLU/CY). Median duration of absolute neutrophil count &amp;lt;1,000/μL was shorter in the BENDA cohort. The incidence of any grade CRS (56% vs. 90%, p=0.06) and tocilizumab use (56% vs. 84%, p=0.16) was lower with BENDA compared to FLU/CY. In the absence of ide-cel expansion data, we used nadir polyclonal IgG and uninvolved free light chain (uFLC) in the initial 90 days post CART cell infusion as surrogate of non-malignant plasma burden and therefore ide-cel expansion. We noted lower median uFLC and median IgG with FLU/CY vs. BENDA. The overall response rate was lower with BENDA (22%) vs. FLU/CY (79%, p=0.01). With median follow up of 4.8 mo., all pts in the BENDA cohort progressed with median PFS of 1.6 months vs 7.8 months for FLU/CY (p&amp;lt;0.001, Figure). The median OS for both cohorts is not yet reached. Conclusion: BENDA LD prior to ide-cel infusion results in suboptimal lymphodepletion and subsequent inferior outcomes including low rate of objective responses and decreased progression free survival. The inferior efficacy of BENDA as LD likely results from inferior ide-cel expansion and persistence resulting in less frequent and severe CRS and cytopenias and less suppression of unaffected immunoglobulins. Future efforts to study alternative lymphodepletion approaches is essential given inability to use fludarabine in patients with severe renal dysfunction and periods of critical drug shortages. While there is a need to develop alternatives for LD prior to ide-cel, BENDA is an inadequate substitute of FLU/CY.

First-Line Venetoclax Combinations in Chronic Lymphocytic Leukemia

BackgroundRandomized trials of venetoclax plus anti-CD20 antibodies as first-line treatment in fit patients (i.e., those with a low burden of coexisting conditions) with advanced chronic lymphocytic leukemia (CLL) have been lacking.MethodsIn a phase 3, open-label trial, we randomly assigned, in a 1:1:1:1 ratio, fit patients with CLL who did not have TP53 aberrations to receive six cycles of chemoimmunotherapy (fludarabine–cyclophosphamide–rituximab or bendamustine–rituximab) or 12 cycles of venetoclax–rituximab, venetoclax–obinutuzumab, or venetoclax–obinutuzumab–ibrutinib. Ibrutinib was discontinued after two consecutive measurements of undetectable minimal residual disease or could be extended. The primary end points were undetectable minimal residual disease (sensitivity, <10−4 [i.e., <1 CLL cell in 10,000 leukocytes]) as assessed by flow cytometry in peripheral blood at month 15 and progression-free survival.ResultsA total of 926 patients were assigned to one of the four treatment regimens (229 to chemoimmunotherapy, 237 to venetoclax–rituximab, 229 to venetoclax–obinutuzumab, and 231 to venetoclax–obinutuzumab–ibrutinib). At month 15, the percentage of patients with undetectable minimal residual disease was significantly higher in the venetoclax–obinutuzumab group (86.5%; 97.5% confidence interval [CI], 80.6 to 91.1) and the venetoclax–obinutuzumab–ibrutinib group (92.2%; 97.5% CI, 87.3 to 95.7) than in the chemoimmunotherapy group (52.0%; 97.5% CI, 44.4 to 59.5; P<0.001 for both comparisons), but it was not significantly higher in the venetoclax–rituximab group (57.0%; 97.5% CI, 49.5 to 64.2; P=0.32). Three-year progression-free survival was 90.5% in the venetoclax–obinutuzumab–ibrutinib group and 75.5% in the chemoimmunotherapy group (hazard ratio for disease progression or death, 0.32; 97.5% CI, 0.19 to 0.54; P<0.001). Progression-free survival at 3 years was also higher with venetoclax–obinutuzumab (87.7%; hazard ratio for disease progression or death, 0.42; 97.5% CI, 0.26 to 0.68; P<0.001), but not with venetoclax–rituximab (80.8%; hazard ratio, 0.79; 97.5% CI, 0.53 to 1.18; P=0.18). Grade 3 and grade 4 infections were more common with chemoimmunotherapy (18.5%) and venetoclax–obinutuzumab–ibrutinib (21.2%) than with venetoclax–rituximab (10.5%) or venetoclax–obinutuzumab (13.2%).ConclusionsVenetoclax–obinutuzumab with or without ibrutinib was superior to chemoimmunotherapy as first-line treatment in fit patients with CLL. (Funded by AbbVie and others; GAIA–CLL13 ClinicalTrials.gov number, NCT02950051; EudraCT number, 2015-004936-36.)

Conditioning Regimens are Associated with Distinct Patterns of Microbiota Injury in Allogeneic Hematopoietic Cell Transplantation.

The gut microbiota is subject to multiple insults in allogeneic hematopoietic cell transplantation (allo-HCT) recipients. We hypothesized that preparative conditioning regimens contribute to microbiota perturbation in allo-HCT. This was a retrospective study that evaluated the relationship between conditioning regimens exposure in 1,188 allo-HCT recipients and the gut microbiome. Stool samples collected from 20 days before transplantation up to 30 days after were profiled using 16S rRNA sequencing. Microbiota injury was quantified by changes in α-diversity. We identified distinct patterns of microbiota injury that varied by conditioning regimen. Diversity loss was graded into three levels of conditioning-associated microbiota injury (CMBI) in a multivariable model that included antibiotic exposures. High-intensity regimens, such as total body irradiation (TBI)-thiotepa-cyclophosphamide, were associated with the greatest injury (CMBI III). In contrast, the nonmyeloablative regimen fludarabine-cyclophosphamide with low-dose TBI (Flu/Cy/TBI200) had a low-grade injury (CMBI I). The risk of acute GVHD correlated with CMBI degree. Pretransplant microbial compositions were best preserved with Flu/Cy/TBI200, whereas other regimens were associated with loss of commensal bacteria and expansion of Enterococcus. Our findings support an interaction between conditioning at the regimen level and the extent of microbiota injury.

The differential effects of tumor burdens on predicting the net benefits of ssCART-19 cell treatment on r/r B-ALL patients

The tumor burden (TB) is significantly related to the severity of cytokine release syndrome (CRS) caused by CAR-T cells, but its correlation with therapeutic efficacy has not been systematically studied. This study focused on the effects of the TB level on both the safety and efficacy of ssCART-19 as a treatment for r/r B-ALL. Taking the 5% tumor burden as the boundary, the study participants were divided into 2 groups, high and low tumor burden groups. Under this grouping strategy, the impacts of differential r/r B-ALL TBs on the clinical therapeutic efficacy (CR rate and long-term survival) and safety profiles after ssCART-19 cell treatment were analysed. 78 patients were reported in this study. The differential B-ALL TBs significantly affected the complete remission (CR) rates of patients treated with ssCART-19, with rates of 93.94% and 75.56% in the low and high TB groups, respectively (P = 0.0358). The effects of TBs on long-term therapeutic efficacy were further studied based on event-free survival (EFS) and overall survival (OS) profiles; both the OS and EFS of the low TB group were better than those of the high TB group, but the differences were not statistically significant. Importantly, the time points of TB measurement did not significantly affect the OS and EFS profiles regardless of whether the TBs were measured before or after fludarabine-cyclophosphamide (FC) preconditional chemotherapy. On the other hand, the severity of CRS was significantly correlated with the TB level (P = 0.0080), and the incidence of sCRS was significantly related to the TB level (the sCRS incidence increased as the TB level increased, P = 0.0224). Unexpectedly, the ssCART-19 cell expansion peaks were not significantly different (P = 0.2951) between the study groups. Patients with a low r/r B-ALL TB yield more net benefits from CAR-T treatment than those with a high TB in terms of safety and CR rate. These findings are critical and valuable for determining the optimal CAR-T cell treatment window for r/r B-ALL patients and will further the development of comprehensive and reasonable CAR-T cell treatment plans for r/r B-ALL patients with differential TBs.Trial registration: ClinicalTrials.gov identifier, NCT03919240.

Efficacy and Safety of CD19-Targeted CAR-T Cell Therapy for Refractory/Relapsed B-Cell Lymphoma: A Single Center of Real World Data

【Abstract】 Objective To investigate the efficacy and safety of CD19-targeted chimeric antigen receptor T cell (CAR-T cell) for refractory/relapsed B-cell lymphoma. Methods The efficacy and safety of CD19-CAR-T cells(4-1BB costimulatory domain) in treatment of 12 patients with relapsed/refractory B-cell lymphoma from March 2018 to December 2019 in the Department of Hematology of Guangdong Second Province Hospital were collected analyzed retrospectively. There were 9 patients (75%) with diffuse large B cell lymphoma, 1 patient with blastic variant of mantle cell lymphoma, 1 patient(8.3%) with Burkitt lymphoma, 1 patient with B cell non-Hodgkin lymphoma that cannot be classified. 3 patients (25%) with large mass (≥7.5cm) and 9 patients (75%) with ECOG score ≥2. The number of chemotherapy courses received before transfusion was 4-9, the median number of chemotherapy courses was 7. All 12 patients were autogenous mouse CAR-T cells. Fludarabine + Cyclophosphamide (FC) regimen was used for pretreatment before transfusion, and the number of CAR-T cells was 1 ~ 3.69×10 6/kg. Results All 12 patients received CD19-targeted CAR-T cell therapy. There were 9 patients had treatment response, and the total effective rate was 75%. Among them, there were 3 patients with complete response (CR), with CR rate of 25%, and 6 patients with partial response (PR), with PR rate of 50%. Among the 3 patients with CR remained CR at the follow-up date. Among the 6 patients with PR, 4 showed disease progression in the second month after transfusion, and 2 showed disease progression in the third month after transfusion. All the 9 patients with effective treatment had different degrees of cytokine release syndrome (CRS), including 3 level-1 CRS, 4 level-2 CRS, and 2 level-3 CRS. Two of them had grade 2 CRES, and all CRS and CRES were controlled after treatment with IL-6 receptor antagonists and glucocorticoids. None of the 3 patients failed to respond to treatment had CRS. Conclusion CD19-targeted CAR-T cell immunotherapy has been shown to be effective in CD19-antigen positive B-cell lymphoma, and adverse CRS reactions during treatment can be controlled after treatment. Patients who obtained CR seemed to be able to maintain long-term CR status, while patients who failed to obtain CR showed disease progression within a short period of 3 months, suggesting that patients who obtained CR at an early stage could achieve better efficacy. Therefore, how to identify patients who receive CR at an early stage may be a research direction for the clinical application of CAR-T cell immunotherapy in B-cell lymphoma.【Key words】Chimeric antigen receptor T-cell; Relapsed/refractory B cell lymphoma; Efficacy; Safety; Cytokine release syndrome DisclosuresNo relevant conflicts of interest to declare.

Clinical Study on the CD19-Targeted Chimeric Antigen Receptor T-Cell Therapy for Relapsed/Refractory Acute Lymphoblast Leukemia: A Single Center of Real World Data

Objective To evaluate the efficacy and safety of the CD19-targeted chimeric antigen receptor T-cell(CD19-CAR-T) therapy for relapsed/refractory B-cell acute lymphoblast leukemia(B-ALL). Methods The efficacy and safety of CD19-CAR-T cells(4-1BB costimulatory domain) in treatment of 34 patients with relapsed/refractory B-ALL from March 2015 to December 2019 in the Department of Hematology of Guangdong Second Province Hospital were collected analyzed retrospectively. There were 18 cases (52.9%) with high-risk cytogenetic or molecular markers, 14 cases (41.2%) with tumor load was ≥50% before transfusion, 24 cases (70.6%) with ECOG score ≥2. The number of chemotherapy courses received before transfusion was 2-15, the median number of chemotherapy courses was 5. There were 32 autogenous CAR-T cells and 2 donor-derived CAR-T cells, 11 of them received allogeneic hematopoietic stem cell transplantation (allo-HSCT) before transfusion. All were mouse CAR-T cells. Fludarabine + Cyclophosphamide (FC) regimen was used for pretreatment before transfusion, and the number of CAR-T cells was 1 ~ 13.4×10 6/kg. Results All 34 patients received CD19-targeted CAR-T cell therapy. 22 patients obtained MRD- after 1 month, CR rate was 64.7%. 20 patients maintained MRD- after 2 months, and the CR rate was 58.8%. 13 patients still maintained MRD- after 3 months, with a CR rate of 38.2%. 4 patients with recurrence presented CD19 negative recurrence. 10 patients underwent Allo-HSCT after CR acquisition, 6 of them maintained a continuous CR state, and 4 patients died after recurrence. Cytokines release syndrome (CRS) was observed in 31 patients (91.2%). Among them, there were 20 patients (64.5%) with grade 1 ~ 2, 8 patients (25.8%) with grade 3 ~ 4, and 3 patients (9.7%) with grade 5. The cytokines levels of IL-6 and IFN-γ were mainly increased in 20 (64.5%) and 18 (58.1%) patients, respectively. Common clinical adverse reactions are: fever with 32 cases (94.1%), pancytopenia with 28 cases (82.4%), chills with 17 cases (50.0%), fatigue with 26 cases (76.5%), hypotension with 27 cases (79.4%), tachycardia with 24 cases (70.6%), hypofibrinogenemia with 20 cases (58.8%), hypoproglobinemia with 27 cases (79.4%), neurotoxicity with 15 cases (44.1%), nausea with 16 cases (47.1%), vomiting with 14 cases (41.2%), hypoalbuminemia with 25 cases (73.5%), transaminase eleations with 16 cases (47.1%), electrolyte metabolic disorders with 27 cases (79.4%) , hypoxemiawith 15 cases (44.1%). Conclusion CAR-T cells therapy is a novel method for the treatment of refractory/recurrent B-ALL with CD19 antigen positive, which can make patients achieved complete remission in a short time, even achieved MRD negative, and most of the CRS appeared in the process of treatment can be controlled by treatment, but the recurrence rate is higher after 3 months later, and can appear CD19 negative relapse. Allo-HSCT as soon as possible after obtaining CR can enable some patients to obtain sustained CR.Therefore, more clinical studies are needed to explore the clinical application of CAR-T cell therapy. Currently, it is believed that bridging with allo-HSCT may be a solution to achieve sustained CR.【Key words】Chimeric antigen receptor T-cell; Relapsed/refractory acute lymphoblast leukemia; Efficacy; Safety; Cytokine release syndrome DisclosuresNo relevant conflicts of interest to declare.

Clinical Outcome of Refractory Lymphoma Patients with Non Response to Chimeric Antigen Receptor T Cell Therapy

BackgroundChimeric antigen receptor T cell (CART) therapy has remarkably improved the outcome of patients (pts) with relapsed refractory B cell non-Hodgkin lymphoma. Anti-CD19 directed CART therapy have shown to yield durable remission in 40%-50% of patients with relapsed refractory (r/r) diffuse large B cell lymphoma (Neelapu et al. NEJM 2017; NCT 02348216). However, pts who had disease progression post CART therapy (non-responders) have poor outcomes. There is paucity of information regarding negative predictors for disease progression and outcome of non-responders post CART therapy.MethodsWe conducted a single center retrospective study of 11 patients with relapsed refractory large B cell lymphoma who underwent treatment with CART in our institution from December 2019 to June 2021 and further studied the baseline characteristics, and clinical outcome of 8 pts who were non responders to CART therapy.ResultsAll patients received low dose fludarabine cyclophosphamide based lymphodepleting conditioning regimen followed by anti-CD19 directed CART cells using CD28 as costimulatory domain with a target dose of 2 x 10 6 cells /kilogram of body weight.Baseline characteristics as shown in [Table 1]. Median age at CART therapy was 61 years (range 49-71). Median ECOG score at CART therapy was 1. All patients had chemo refractory disease at time of CART therapy with 9 patients having refractory diffuse large B cell lymphoma and 2 patients had transformed large B cell lymphoma. Genomic studies showed high risk disease in 4 patients with double hit lymphoma, 3 patients with complex cytogenetics with one having 17 p deletion and 2 patients with double expressors of c-myc and bcl2. Only 5 patients had available Ki-67 score > 80%. All patients had stage III-IV disease at the time of CART therapy. Seven pts had extra nodal disease and one patient had CNS involvement. Median R-IPI score at time of CART therapy was 3 (range 2-4). Median LDH, serum ferritin and serum CRP at the time of CART therapy was 388 (range 136-1489); 831 (range 116.9-1503); and 28.1 (range 7.4-226) respectively. Median number of prior therapies were 3 (range 2-9). One patient had prior autologous stem cell transplant. Median absolute lymphocyte count (ALC) and platelet count at CART therapy was 0.01/ul (range 0.01-2.5) and 89 x 10 3/ul (range 10-385) respectively. Median time from last salvage chemotherapy to CART therapy was 62 days (range 28-492).Total six pts had cytokine release syndrome (CRS) with median time for CRS onset was 3.5 days (range 1-8) with all of them having grade 1-2 CRS. Total seven pts had neurotoxicity with median time for onset was 5 days (range 1-41) post CART with 4 pts having > grade 3 immune effector cell associated neurotoxicity syndrome (ICANS). Overall, six and seven pts received tociluzumab and steroids respectively for treatment of CART related CRS and ICANS. Day 30 PET/CT scan showed three responders (2CR,1PR) and eight non responder patients with disease progression.Non responder pts to CART, when compared with responders had higher value of median LDH (438 vs 300; p = 0.92); median CRP (29 vs 13; p = 0.497) ; higher extra nodal involvement ( 6 pts vs one), median R-IPI score at the time of CART ( 4 vs 3), median number of prior therapies (4 vs 3), and median time from last salvage therapy to CART ( 73 days vs 50 days ; p = 0.91). No difference in baseline ALC count and platelet count was noted between the two groups. Compared to responders, non-responder pts had lower incidence of CRS (100% vs 37.5%) and ICANS (100% vs 50%). Post CART therapy, non-responder pts were treated with Nivolumab based immunotherapy in 5 pts, Ipilimumab based therapy in 1 pt, Selinexor in 1 patient and Polatuzumab based therapy in 2 pts.Median progression free survival and overall survival of non-responders was only 30.5 days and 94 days respectively. 5 out of 8 non responder pts died (4 due to disease progression and 1 due to sepsis). All three responder pts were alive and disease free at the end of study. Median follow up of our study was 108 days (range 32- 561).ConclusionsDespite smaller sample size, our study showed dismal outcome of pts who don't respond to CART therapy, showing an unmet need for better salvage therapies in such pts. Refractory lymphoma pts with extra nodal disease involvement, higher LDH and CRP at the time of CART therapy could be negative predictors for response. Further prospective studies with larger sample size required to further validate these findings. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Quality of Life in Patients

Quality of Life in Patients <=70 Years of Age with Chronic Lymphocytic Leukemia Treated Frontline with Ibrutinib-Rituximab Versus Fludarabine Cyclophosphamide Rituximab: Analysis from ECOG-ACRIN E1912

Fludarabine–Cyclophosphamide-Based Conditioning with Antithymocyte Globulin Serotherapy Is Associated with Durable Engraftment and Manageable Infections in Children with Severe Aplastic Anemia

Severe aplastic anemia (SAA) is a bone marrow failure syndrome that can be treated with hematopoietic cell transplantation (HCT) or immunosuppressive (IS) therapy. A retrospective cohort of 56 children with SAA undergoing transplantation with fludarabine–cyclophosphamide–ATG-based conditioning (FluCyATG) was analyzed. The endpoints were overall survival (OS), event-free survival (EFS), cumulative incidence (CI) of graft versus host disease (GVHD) and CI of viral replication. Engraftment was achieved in 53/56 patients, and four patients died (two due to fungal infection, and two of neuroinfection). The median time to neutrophil engraftment was 14 days and to platelet engraftment was 16 days, and median donor chimerism was above 98%. The overall incidence of acute GVHD was 41.5%, and that of grade III-IV acute GVHD was 14.3%. Chronic GVHD was diagnosed in 14.2% of children. The probability of 2-year GVHD-free survival was 76.1%. In the univariate analysis, a higher dose of cyclophosphamide and previous IS therapy were significant risk factors for worse overall survival. Episodes of viral replication occurred in 33/56 (58.9%) patients, but did not influence OS. The main advantages of FluCyATG include early engraftment with a very high level of donor chimerism, high overall survival and a low risk of viral replication after HCT.

Оценка факторов риска развития поражений печени у больных хронической лимфоцитарной лейкемией в динамике химиотерапии

Актуальность. Лечение В-клеточной хронической лимфоцитарной лейкемии (В-ХЛЛ) сопровождается риском развития поражений печени, что связано с факторами, которые зависят от особенностей пациента, опухоли, и химио­терапией (ХТ). Цель — оценить риск развития и характер нарушений печеночных тестов у больных В-ХЛЛ в динамике ХТ. Материалы и методы. Обследовано 76 больных В-ХЛЛ, из них 44 (57,9 %) мужчины и 32 (42,1 %) женщины. Средний возраст — (66,81 ± 12,50) года. Стадию В-ХЛЛ определяли по классификациям К. Rai (1975, 1987) и J. Binet (1981, 2006). Назначали ХТ по схеме FC (флударабин, циклофосфан). Обследование проводили перед ХТ и после двух курсов FC. Учитывали гиперпластический синдром, гиперлейкоцитоз. Оценивали показатели биохимического анализа крови. Использовали критерии Common Terminology Criteria for Adverse Events (CTCAE), Version 4.02. Результаты. Поздние стадии В-ХЛЛ, ІV по Rai и С по Binet, у больных В-ХЛЛ ассоциируются с ростом риска не получить ответы на ХТ (отношение рисков (RR) 0,53; 95% доверительный интервал (ДИ) 0,31–0,90; р &lt; 0,05). Наличие гиперпластического синдрома сопровождается достоверным риском не достичь ответа на ХТ (RR 0,23; 95% ДИ 0,07–0,80; р &lt; 0,05). Поражение печени чаще регистрируют у больных В-ХЛЛ в III стадии (RR 1,96; 95% ДИ 1,33–2,88; р &lt; 0,05) и IV стадии (RR 2,13; 95% ДИ 1,47–3,08; р &lt; 0,05) по сравнению со ІІ стадией по Rai. У больных В-ХЛЛ риск развития гепатотоксических реакций ассоциируется с низкой эффективностью ХТ, а именно достижением частичного ответа (RR 3,18; 95% ДI 1,93–5,22; р &lt; 0,05) и отсутствием ответа на ХТ (RR 3,71; 95% ДI 2,37–5,81; р &lt; 0,05). Выводы. Риск возникновения поражений печени возрастает у больных В-ХЛЛ IV (С) стадии и ассоциируется с низкой эффективностью ХТ.

High IGF1R Expression Is Associated with Worse Prognosis in CLL and Impacts Response to PI3K-δ Inhibitor Treatment

High IGF1R Expression Is Associated with Worse Prognosis in CLL and Impacts Response to PI3K-δ Inhibitor Treatment

Real-World Outcomes of Chemoimmunotherapy in Chronic Lymphocytic Leukemia (CLL) Clinical Practice: Results from a Decade of Practice in Helsinki 2005-2015

Introduction: Around 350 new CLL cases are diagnosed annually in Finland, with approximately 1800 individuals living with the disease. However, no comprehensive disease outcome studies from clinical practice have been conducted to-date. In the absence of direct head-to-head trials, robust historical control data have become requisite to complement available clinical trial data and estimate the potential effects of novel therapies in local practice. In addition, patients (pts) in routine clinical care are far more heterogeneous than those included in clinical trials. The Finnish Hematology Registry (FHR) was created to collect real-world practice outcomes in CLL and other hematological malignancies, with Finland's centralized nationwide healthcare system allowing reliable pt identification and complete follow-up. The objective of this registry study is to describe treatment and survival outcomes for CLL pts from routine practice settings.Methods: A non-interventional, retrospective study design was used to collect routine clinical practice data from the FHR. Eligible pts aged ≥18 years diagnosed with CLL and receiving 1 or more treatment lines during 2005-2015 were identified from the FHR, with groupings of pts into those treated in the early (2005-2007), middle (2008-2010) and late (2011-2015) cohort time periods. As the registry had limited CLL pt data at study start, clinical investigators accessed medical records to retrieve and validate data. We report interim results on 66 pts from the Helsinki University Hospital, Helsinki, Finland, a hospital region accounting for 30% of the total national CLL incidence. The completion and validation of the Helsinki cohort (~130 pts) is ongoing and results from the whole dataset will be presented at ASH.Results: Median age at diagnosis was 67 years and 23% had Binet stage C. Longitudinal follow-up was available from 1st to 7th or higher treatment lines. Across all treatment lines, fludarabine-cyclophosphamide-rituximab (FCR) (52%), bendamustine-rituximab (BR) (48%), fludarabine-cyclophosphamide (FC) (27%), and chlorambucil (chl) -based therapies (24%) were the most frequently used treatments. FCR (48%) and FC (27%) were frequently used in the 1st line, whereas BR (34%) was the primary choice in the 2nd line. In later lines a wide array of treatment regimens were used. Only 2 pts received the novel agent ibrutinib as part of a named patient program; no other novel agents were used in this cohort during this period.FC and FCR were initiated in equal yet constantly decreasing proportions through 2008, when FCR became most common (0% FC vs. 40% FCR). A year later in 2009, BR was introduced into clinical practice and its use increased steadily from 14% to 30% through 2014 when its use then declined. The peak year of chl monotherapy or chl-based combinations was in 2006 with 38% of pts receiving chl-based treatment. Since then chl use has decreased dramatically, to 0% in 2015.Median overall survival (OS) from the start of any given 1st line treatment was 81 months (m). Pts receiving FC (p=0,009) and FCR (p<0,001) had significantly longer median OS (79 m and 82 m respectively) compared to bendamustine/BR (62 m) when given in the 1st line. FC and FCR resulted in longer, though not statistically different, time-to-next-treatment (TTNT) compared to bendamustine/BR (77 m vs 44 m). Despite the observed practice changes over the years, there were no detectable outcome differences in 1st and 2nd line median OS between those treated in early, middle and late time periods, possibly due to limited follow-up in the later period (data not shown).Conclusions: We describe real-world treatment trends and outcomes from a decade of practice in the Helsinki region. Our results show that chemoimmunotherapies have been vigorously implemented in clinical practice. However, interim results do not show detectable improvements for OS and TTNT during this decade of treatment in the Helsinki hospital region. In the Nordics, real-world evidence has become essential when introducing novel targeted therapies into clinical practice settings, with comprehensive disease registries expanding to allow for more detailed follow-up. [Display omitted] DisclosuresJarvinen:Janssen-Cilag Oy: Employment. Mehtälä:EPID Research: Employment, Other: EPID Research is a contract research organization that performs commissioned pharmacoepidemiological studies and thus its employees have been and currently are working in collaboration with several pharmaceutical companies.. Khanfir:EPID Research: Employment, Other: EPID Research is a contract research organization that performs commissioned pharmacoepidemiological studies and thus its employees have been and currently are working in collaboration with several pharmaceutical companies.. Juuti:EPID Research: Employment, Other: EPID Research is a contract research organization that performs commissioned pharmacoepidemiological studies and thus its employees have been and currently are working in collaboration with several pharmaceutical companies.. Leval:Janssen-Cilag Ab: Employment.

Epidemiology, longitudinal treatment patterns and outcomes of chronic lymphocytic leukemia in Israel

This study aims to describe chronic lymphocytic leukemia (CLL) epidemiology, treatment patterns and outcomes in a 2.3-million-member healthcare provider database (Maccabi Healthcare Services, Israel). Newly-diagnosed CLL patients (1999–2017) were followed through 31/3/2018. A total of 1857 newly-diagnosed CLL patients were included. Annual incidence was 5.82 per 100,000 population. Median overall survival (OS) was 12.7 (95%CI: 11.8–13.5) years since diagnosis. Approximately 1/3 initiated treatment within 5 y. A statistical trend (p = 0.066) for improved OS over time was observed among younger patients (age <70 y) treated in 2009–2017 vs. 1999–2008). Among patients treated since 2009 (n = 411; median age = 68y), fludarabine–cyclophosphamide–rituximab (FCR), bendamustine–rituximab and obinutuzumab ± chlorambucil accounted for 19.5%, 12.2% and 11.4% of first line, respectively. Median (95%CI) time to next treatment and OS were 3.1(2.6–3.6) and 7.0(6.3–7.7) years, respectively. CLL incidence in Israel is comparable to developed countries. Real-world data suggest a trend of improved survival over the last decade among patients treated before age 70.

Telomere Length and CD49d Cooperate with IGHV Gene Status As Predictors of Long-Term Progression-Free Survival in CLL Patients Treated with FCR-Based Regimens

Background - Although there has been a revolution in the treatment of chronic lymphocytic leukemia (CLL), the challenge remains to identify the right drugs for the right patients. It is widely accepted that CIT, including the 'gold standard' fludarabine, cyclophosphamide and rituximab (FCR), is contraindicated for patients with TP53 disruption and, more recently, unmutated IGHV genes. Also patients with short, dysfunctional telomeres were shown to have inferior outcomes when treated with FCR-based regimens. To date, a role for CD49d in this setting has not been established. Aims - Here we evaluated the ability of telomere lenght (TL) and CD49d to cooperate with IGHV gene status to predict progression-free survival (PFS) in patients treated with FCR-based regimens in the frontline setting in three UK trials, ARCTIC, ADMIRE and CLL4. Methods - The study included a discovery cohort of 245 CLL treated with FCR/FCR-like regimens according to the two UK trials ARCTIC and ADMIRE. As there was no significant difference in PFS between the three arms of the study (P = 0.97), analysis was performed on the combined cohort. The median follow-up was 77.5 months with 157 progressions and 76 deaths. Twenty-nine patients were TP53 deleted and/or mutated, with shorter PFS compared to cases without TP53 disruption (final cohort, 216 TP53 wild-type CLL). The validation cohort was composed of 119 CLL samples derived from patients randomised to receive fludarabine, cyclophosphamide (FC) from the UK CLL4 trial. The median follow-up was 67.2 months with 99 progressions and 77 deaths. Fifteen CLL were TP53 mutated/deleted, with shorter PFS compared to cases without TP53 disruption (final cohort, 104 TP53 wild-type CLL). TL was measured using the high-throughput STELA assay and patients were bifurcated into two groups with either short telomeres inside the fusogenic range (TL-IFR) or long telomeres outside the fusogenic range (TL-OFR). CD49d was measured by flow cytometry and dichotomized as CD49dpos and CD49dneg based on the established 30% cut-off. For IGHV gene status, the 2% cutoff was used to split patients in mutated (IGHV-M) and ummutated (IGHV-UM). Results - In the 216 CLL with wild-type TP53 status from the ARCTIC/ADMIRE trials, CD49d expression was a predictor of PFS (P=0.02; HR=1.46 [1.03-2.06]). In keeping with previous reports, patients with IGHV-UM genes (P&amp;lt;.0001; HR=2.53 [1.79-3.58]) or TL-IFR (P=0.0002; HR=1.97 [1.30-2.98]) showed also significantly shorter PFS. This data was used as a starting point for a risk-stratification algorithm (Figure 1A). IGHV-UM cases could not be further dissected by TL or CD49d expression (P=0.76 log-rank test), their 8-year PFS being just 19.0%; (HR=5.58 [3.70-8.42]). In contrast, the IGHV-M group could be stratified by TL and CD49d expression (P&amp;lt;0.001 log-rank test). In particular, 13/84 (15.5%) of IGHV-M CLL with TL-IFR showed a median PFS of 3.0 years with a 8-year PFS of 15.4% (HR=6.45 [1.84-22.58]), similar to IGHV-UM cases (P = 0.19). Patients with IGHV-M genes and TL-OFR could be further stratified by CD49d expression into categories with different 8-year PFS: 43.1% in IGHV-M/TL-OFR/CD49dpos cases (HR=2.52 [1.08-5.89]), and 75.5% in the IGHV-M/TL-OFR/CD49dneg reference group (Table 1). Figure 1B shows the overlaid Kaplan-Meier curves for this hierarchical stratification. The proposed algorithm was then evaluated in the UK CLL4 trial. In keeping with the known inferiority of FC when compared with FCR, the 8-year PFS was just 5.2% in the IGHV-UM subset, irrespective of TL or CD49d expression. In concordance with the discovery cohort, the IGHV-M subset with TL-IFR had a similar median PFS to IGHV-UM cases (P=0.84). Furthermore, CD49d expression was able to stratify cases with TL-OFR; in particular, 18/104 (17.3%) were IGHV-M/TL-OFR/CD49dneg CLL which had a 8-year PFS of 77.8% (summary in Table 1 and Figure 1C). Conclusion - Our analysis shows that only IGHV-M/TL-OFR/ CD49dneg patients may benefit from CIT; this group represented just 56/321 cases (17.4%) of the combined cohort, suggesting that approximately 82% of patients should be considered for alternative therapies. Incorporation of this algorithm into clinical trial design and real-world practice would enable rational, risk-adapted, clinical management with the aim of treating all CLL patients with the optimal therapeutic regimen in the frontline setting. Disclosures Norris: TeloNostiX Ltd: Current equity holder in private company, Patents &amp; Royalties. Hillmen:Gilead: Other: Financial or material support, Research Funding; Alexion: Consultancy, Research Funding, Speakers Bureau; Apellis: Consultancy, Research Funding, Speakers Bureau; AstraZeneca: Consultancy, Speakers Bureau; Acerta: Other: Financial or material support; Roche: Consultancy, Other: Financial or material support, Research Funding, Speakers Bureau; AbbVie: Consultancy, Other: Financial or material support, Research Funding, Speakers Bureau; Pharmacyclics: Other: Financial or material support, Research Funding; Janssen: Consultancy, Other: Financial or material support, Research Funding, Speakers Bureau. Rawstron:BD Biosciences (Intrasure): Patents &amp; Royalties. Baird:TeloNostiX Ltd: Current equity holder in private company, Patents &amp; Royalties. Fegan:TeloNostiX Ltd: Current equity holder in private company, Patents &amp; Royalties. Pepper:TeloNostiX Ltd: Current equity holder in private company, Patents &amp; Royalties.

Non-Myeloablative Conditioning Regimen before T-Cell Replete Haploidentical Transplantation with Post-Transplant Cyclophosphamide for Advanced Lymphoma

Introduction: allogeneic transplantation (allo-HSCT) is a curative treatment for patients with advanced lymphoma. Haploidentical (haplo-SCT) transplantation extended the accessibility to allo-HSCT, overcoming the issue of donor availability. However, alternative donor allo-HSCT is still considered at higher risk of non-relapse mortality due to the HLA disparity and thus an anticipated higher incidence of GVHD. In this context, the use of a non myeloablative conditioning (NMAC) regimen combined with post transplantation cyclophosphamide (PT-Cy) based GVHD prophylaxis may reduce procedure related toxicity. The aim was to evaluate the toxicity and efficacy of haplo-SCT using NMAC with PT-Cy in advanced lymphoma patients. Methods: We here report the retrospective experience of a bicentric transplantation program. We analyzed a cohort of lymphoma patients undergoing Haplo-SCT and homogeneously receiving NMAC and PT-Cy. Inclusion criteria were: 1) first allo-HSCT for advanced lymphoma between 2009 and 2018; 2) haploidentical donor; 3) NMAC (fludarabine cyclophosphamide and 2 gray TBI GVHD prophylaxis consisted of PT-Cy day+3 and +4 , cyclosporine A and MMF starting from day +5. Multivariate analyses included age, disease type (NHL vs HL), HCT-CI (&lt; vs ≥ 3), graft source (PBSC vs BM), disease status at haplo-SCT (CR vs other). Results: One hundred forty seven patients (73 NHL; 74 HL) with a median age of 46 years (range: 19-71) were included. PBSC (peripheral blood stem cell) was used as graft source in 96 patients (65%). Patients received a median number of 3 conventional chemotherapy lines before haplo-SCT (1-8). Sixty-five (44%) had relapse after Auto-HCT. At the time of haplo-SCT, 96 patients (66%) were in complete remission. The cumulative incidences of day+100 grade 2-4 and 3-4 acute GVHD were 30% and 3%, respectively. The cumulative incidences of 2-year chronic and moderate or severe chronic GVHD were 13% and 8%, respectively. With a median follow up of 39 months (6-114), 2-year NRM was 14%, with a trend for higher risk in patients with HCT-CI ≥ 3 (HR 0.39, 95CI [0.15-1.04] p = 0.061) while age was not associated with an increased risk of NRM (HR 1.01, 95CI [0.98-1.05], p = 0.450). Two-year cumulative incidence of relapse (CIR) was 21% and 18% in HL and NHL patients, respectively. Disease status at the time of haplo-SCT was strongly associated with relapse (HR 2.99, 95CI [1.41-6.35], p = 0.004) In HL patients, 2-year PFS, OS and GRFS were 65%, 77% and 57%, respectively, while corresponding values in NHL patients were 65%, 69% and 55%, respectively. Two-year PFS and GRFS were significantly higher in patients who underwent haplo-SCT in CR (PFS: CR vs. no CR: 72% vs. 55%, p=0.045; GRFS: CR vs. no CR: 63% vs. 42%, p=0.010). There was a trend for better 2-year OS in CR (OS: CR vs. no CR: 78% vs. 63%, p=0.063. Conclusion: We confirm the feasibility of haplo-SCT using NMAC and PT-Cy with low incidence of GVHD (notably severe forms) and NRM. In addition, we observed a relatively low incidence of relapse (19%) in this cohort of heavily pretreated patients, underlining a potent graft-versus-lymphoma effect after haplo-SCT, leading to promising survivals, including high rate of GRFS (&gt;50%), suggesting a preserved long term quality of life in survivors. We conclude that NMAC haplo-SCT with PT-Cy should be considered as a valuable curative option for advanced lymphoma patients, with a favorable toxicity profile and promising long term survival. Figure Disclosures Stoppa: celgene: Other: travel fees, lecture fees; takeda: Other: travel fees. Carlo-Stella:MSD: Honoraria; BMS: Honoraria; Janssen: Other: Travel, accommodations; Boehringer Ingelheim: Consultancy; Genenta Science sr: Consultancy; Sanofi: Consultancy, Research Funding; ADC Therapeutics: Consultancy, Other: Travel, accommodations, Research Funding; Novartis: Consultancy, Research Funding; Servier: Consultancy, Honoraria, Other: Travel, accommodations; F. Hoffmann-La Roche Ltd: Honoraria, Other: Travel, accommodations, Research Funding; Rhizen Pharmaceuticals: Research Funding; Celgene: Research Funding; Amgen: Honoraria; Takeda: Other: Travel, accommodations; Janssen Oncology: Honoraria; AstraZeneca: Honoraria. Chabannon:EBMT: Other: Working Party Chair, Board member; Fresenius Kabi: Other: research support; Miltenyi Biotech: Other: research support; Terumo BCT: Other: speaker's fees; Celgene: Other: speaker's fees; Novartis: Other: speaker's fees; Gilead: Other: speaker's fees, hospitalities; Sanofi SA: Other: research support, speaker's fees, hospitalities. Santoro:Takeda: Speakers Bureau; BMS: Speakers Bureau; Roche: Speakers Bureau; Abb-Vie: Speakers Bureau; Amgen: Speakers Bureau; Celgene: Speakers Bureau; Servier: Consultancy, Speakers Bureau; Gilead: Consultancy, Speakers Bureau; AstraZeneca: Speakers Bureau; Pfizer: Consultancy, Speakers Bureau; Arqule: Consultancy, Speakers Bureau; Lilly: Speakers Bureau; Sandoz: Speakers Bureau; Eisai: Consultancy, Speakers Bureau; Novartis: Speakers Bureau; Bayer: Consultancy, Speakers Bureau; MSD: Speakers Bureau; BMS: Consultancy. Blaise:Sanofi: Honoraria; Jazz Pharmaceuticals: Honoraria; Molmed: Consultancy, Honoraria; Pierre Fabre medicaments: Honoraria.

Maintenance of Long-Term Undetectable Minimal Residual Disease after Combination of Ibrutinib with Abbreviated Chemotherapy in the Icll-07 Filo Trial

Maintenance of Long-Term Undetectable Minimal Residual Disease after Combination of Ibrutinib with Abbreviated Chemotherapy in the Icll-07 Filo Trial

Chronic Lymphocytic Leukemia in Kuwait

Background :Chronic lymphocytic leukemia (CLL) is common malignancy in Western countries. However, little known about this disease entity in our area. This study exploring the biology in out patients' population. Method:Patients with confirmed CLL under IGHV and TP53 mutational analysis at presentation or during follow up. We also integrated other clinical and biological parameter in this study. Results: A total of 137 cases were analyzed, median age 61 years (range:34-89); 30% of the cases age was&lt;55 years at presentation. There was 108 males vs. 29 females M:F ratio 3.7. Two patients gave a family history of CLL, while 1 patient gave a history of other lymphoproliferative disorders. Binet staging system available in 134 cases, A: 109 (81.3%), B: 12 (9%), C:13 (9.7%). B2 macroglobulin elevated in 40/112 (36%) cases and 10/103 (10%) had M-spike. CD38 positivity reported in 37/112 (33%) of cases. Cytogenetics data evaluable in 85 cases: isolated del(13q): 35%, isolated trisomy 12 (16.5%), del(11q) (4.5%), del(17p)(2.4%). IGHV mutational status mutated vs unmutated: 40% vs 60%. Cases with available treatment information on 132 cases. Fifty cases required treatment due to disease progression. First line treatment Bendamustine-Rituximab (BR) 3 cases, Fludarabine Cyclophosphamide Rituximab (FCR) 30 cases and Chlorambucil with anti-CD 20 antibody 6 cases. At the time of review, 3 cases on ibrutinib (2 in 3rdline and 1 case in the 4thline). Conclusion: This is the first study to shed light on CLL in our area. There are biological differences between our patients' population and the western countries. Disclosures Pandita: Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen Cilag: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees.

Mechanisms of failure of chimeric antigen receptor T-cell therapy.

Although chimeric antigen receptor T (CART)-cell therapy is best recognized for its antitumor effect in relapsed/refractory B-cell hematological cancers, it is still associated with a high relapse rate. We firstly analyzed internal immunological and genetic reasons of CD19+ relapse after treatment for R/R B-cell hematological cancers with CART19 cells. The reasons: murine-derived scFv may limit expansion of CART cells. Repeated antigen exposure leads to T-cell exhaustion. Activation of T cells can cause T-cell senescence and high expression of inhibitive receptors, PD-1, CTLA4, TIGIT, LAG-3, CD244, CD160, TIM3, which might be solved by some external pharmacological intervention methods [for instance, the use of FC (Fludarabine, Cyclophosphamide) lymphodepletion regimen, lenalidomide, PD-1 inhibitor, ibrutinib and humanized CD19-CART cells. Secondly, mechanism of CD19 relapse can be attributed to the preexisting of CD19 subclone, the loss or alternative RNA splicing on exon 2 of chromosome 16 on which CD19 gene is located, B-cell transcript factors - paired-box 5 (PAX5) and early B-cell factor 1 (EBF1) are down-regulated to cause lineage-switch from lymphoid to myeloid. Although different preparation techniques generates various entities of CART 19 cells, these problems could be conquered by novel agents and novel CAR system. Although Chimeric Antigen Receptor T (CART) cell therapy is best recognized for its antitumor effect in Relapsed/Refractory B-cell hematological cancers, it still shows a high relapse rate. We review mechanisms of failure of CART therapy. http://links.lww.com/COH/A18.