Young Adult Acute Lymphoblastic Leukemia Research Articles

Immunophenotypic Characteristics and Cytogenetic Analysis of Adolescent and Young Adult B-Cell Acute Lymphoblastic Leukemia: Correlations With Clinicopathological Parameters.

Introduction Acute lymphoblastic leukemia (ALL) has suboptimal survival rates for adolescents and young adults (AYA) as compared to children. Very limited studies have been conducted on AYA patients in India. This study aimed to identify the cytogenetic and immunophenotype characteristics of B-cell ALL (B-ALL) in AYA patients and determine its correlation with clinicopathological parameters in the Southern India region. Method The study was a prospective study conducted for three years, from June 2019 to May 2022, in India. Newly diagnosed 90 patients with AYA (13-40 years) ALL were recruited. A B-ALL diagnosis was made based on morphology with cytochemical stains and immunophenotype by flow cytometry (FCM). Cytogenetic analysis was also performed using karyotyping and fluorescent in situ hybridization to identify chromosomal aberrations. The cytogenetics results were correlated with immunophenotyping and clinicopathological characteristics. Variables were analyzed using the Mann-Whitney U test and Chi-square test using IBM SPSS Statistics for Windows, Version 20.0 (Released 2011; IBM Corp., Armonk, NY, USA). Results The mean age was 22.68 ± 8.06 years. It was observed that the most common structural chromosomal abnormality for AYA was t(9;22) in 14 (15%) cases, followed by 6q deletions in seven (8%) cases, t(1;19) in four (4%) cases, and t(12;17) and t(6;14) in two (2%) cases each. In addition, t(3;12), t(2;11), t(12;21), t(1;9), t(2;12), and t(X;10) were found in one (1%) case each. The most common numerical abnormality was hyperdiploidy (15; 17%), followed by hypodiploidy (10; 11%). Further, myeloid antigen expression of CD33 was the most common aberrantly expressed marker found in 20 (28%) cases, followed by CD15 in three cases (5%), CD13 in three (4%) cases, and CD11b in two (3%) cases. It was also observed that in Ph+ve cases, CD33 and CD13 were most commonly expressed in three (33%) and two (17%) cases, respectively. In contrast, in Ph-ve patients, their expressions were lesser at 17 (27%) and one (2%) cases, respectively. In addition, leukemia-associated immunophenotype pattern (LAIP) markers CD44 6 (86%) and CD123 5 (55%) were also found to be significantly associated with Ph+ve, whereas their values in the Ph-ve group were lesser at 25 (42%) and 9 (17%), respectively. Our data also showed that older age wassignificantly associated with Ph+ve with a median age of 30 years (p = 0.012). In comparison, the median age of Ph-ve was only 21 years. Conclusion Our study established that the incidence of cytogenetic abnormalities for AYA was consistent with previously reported data. This study reaffirms that Ph+ve cases have significant associations with MyAg (CD13), LAIP (CD123 and CD44), and older age for the South Indian population.

Abstract 45: Driving AMPK signaling in CD4+ CART cells enhances metabolic capacity, memory formation, and anti-leukemia activity

Abstract Background: While Chimeric Antigen Receptor (CAR)T cell therapy has seen great success in pediatric and young adult acute lymphoblastic leukemia, up to 50% of patients will relapse following treatment. Increased memory formation and mitochondrial capacity, particularly in the CD4+ subset, have been linked to improved CART cell function and enhanced in vivo persistence, leading to long-term relapse-free survival. AMP-activated protein kinase (AMPK) is a cellular energy sensor responsible for promoting metabolic efficiency and T cell memory formation. We have previously demonstrated AMPK activity can be increased in human T cells via overexpression of the AMPKγ2 domain. We hypothesized that overexpression of AMPKγ2 in CART cells would enhance their metabolic capacity and improve their anti-leukemia function. Methods: Human CART cells bearing a CD19-CAR utilizing a 41BB costimulatory domain were generated from healthy human donors via lentiviral transduction and co-transduced with AMPKγ2 (AMPK) or an empty vector (EV) control. Flow sorting for the co-transduced populations yielded >95% CD4+ CART cells. CARTs were expanded in IL-2 for approximately 2 weeks, followed by overnight stimulation and subsequent metabolic analysis using the Seahorse Metabolic Analyzer. Memory status was assessed by CD62L and CCR7 co-expression. In vitro CART function was assessed using Zs-green+ NALM6 targets, with loss of green fluorescence over time measured on the Incucyte analyzer. Where indicated, tumor conditioned media was harvested from 72-hour NALM6 cultures. For in vivo experiments, immunodeficient NOD-scid IL2Rγnull (NSG) mice were injected with luciferase+ NALM6 targets, followed one week later by AMPK- or EV-CARTs. Leukemia burden, via IVIS imaging, and survival were followed over time. Results: CD4+ CARTs co-transduced with AMPKγ2 (AMPK-CARTs) increased oxygen consumption, maximal respiration, and spare respiratory capacity following overnight stimulation by ~20% compared to CARTs co-transduced with the EV (EV-CARTs) (p<0.05). Following expansion, CD62L+CCR7+ central memory cells were 4.5-fold more abundant in the AMPK-CART group (2.4-6.2-fold, p<0.01). In vitro, while AMPK-CARTs demonstrated similar cytotoxicity against NALM6 targets as EV-CARTs in standard media, they mediated faster killing of NALM6 targets when challenged in tumor conditioned media (p<0.001). In vivo, recipients of AMPK-CARTs showed a consistent decrease in tumor burden as measured by median radiance values, translating to a significant survival advantage (p<0.05). Conclusions: Increasing AMPK signaling in CD4+ CARTs via overexpression of AMPKγ2 improved metabolic profile, increased memory generation, and enhanced toxicity against leukemia targets both in vitro and in vivo. Together, these features make elevating AMPK signaling an attractive method to increase the efficacy of CART therapy. Citation Format: Erica Braverman, Herbert Schuler, Mengtao Qin, Craig Byersdorfer. Driving AMPK signaling in CD4+ CART cells enhances metabolic capacity, memory formation, and anti-leukemia activity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 45.

Acute lymphoblastic leukemia in young adults: which up-front treatment?.

Significant improvements have occurred for adolescent and young adult (AYA) B-cell acute lymphoblastic leukemia (B-ALL) patients following the widespread adoption of "pediatric-inspired" treatment regimens for AYA patients cared for in adult oncology settings. However, for AYA patients, aged 15 to 39, an outcomes gap remains in B-ALL, necessitating the incorporation of novel therapies into up-front treatment regimens. As a result, clinical trial enrollment remains the current standard of care for AYA B-ALL across disease subtypes when available and accessible. Currently, several up-front trials are looking to incorporate the use of inotuzumab, blinatumomab, and chimeric antigen receptor T-cell therapy into existing chemotherapy backbones for AYA patients, as well as tyrosine kinase inhibitors for both Philadelphia-positive (Ph+) and Ph-like B-ALL. In addition to ongoing attempts to improve up-front treatments by incorporating immunotherapy and targeted approaches, the increased use of next generation sequencing for measurable residual disease evaluation has led to superior risk-stratification and a decreased need to pursue consolidative hematopoietic stem cell transplantation during the first complete remission for many patients.

Establishing Costs for Commercial Chimeric Antigen Receptor T-Cell (Tisagenlecleucel; Kymriah) in Children and Young Adult B-Cell Acute Lymphoblastic Leukemia; A Merged Analysis from the Prwcc and PHIS

Background: Chimeric antigen receptor (CAR) T cell therapy has achieved remarkable efficacy in children and young adult (CAYA) B-cell acute lymphoblastic leukemia (B-ALL). Nonetheless, this therapy is highly personalized, technically complex, and costly to manufacture. The USA FDA approved the first CAR T cell therapy (Kymriah) in Aug 2017, for relapsed/refractory CAYA B-ALL. The list price of Kymriah is $475,000, not accounting for costs related to delivery of care, inpatient hospitalization, toxicity management or follow-up. A half-decade of clinical experience has amassed since commercialization, yet financial analyses remain sparse. Here, we conduct the first study to understand costs for commercial CAR in CAYA B-ALL. Methods: Ten centers participating in both the Pediatric Real-world CAR Consortium (PRWCC) and Pediatric Health Information System (PHIS; Children's Hospital Association, Lenexa, KS) were eligible for study (08/2017-03/2020). Clinical data from the PRWCC database was merged with PHIS using age, diagnosis, center and lymphodepletion dates. Utilizing center and year specific charge-to-cost ratio, PHIS provided data for inpatient admission associated costs, but not outpatient care. For patients that were infused outpatient and subsequently admitted, only inpatient cost was available and analyzed for the first 60 days post-infusion. For patients that were infused inpatient, cost was calculated from the first day of admission for lymphodepletion or Kymriah infusion to 60 days post-infusion. The 60-day follow up was chosen as most of the clinical activity and toxicities occur within the 60 days post-infusion. Each patient was assigned a cost of $475,000 for Kymriah (list price). For the subset of patients who underwent allogeneic hematopoietic cell transplantation (alloHCT) following Kymriah, the median inpatient cost was assessed for 1-year post-alloHCT. Cost data was analyzed as medians and ranges. Univariable and multivariable logistic regression models were used to identify factors associated with the higher median cost associated with inpatient admissions. Results: 109 Kymriah-recipients were included. Patient characteristics are listed in Table 1. The incidence of grade 1-2 and ≥3 CRS was 42% and 23%, respectively, and grade 1-2 and ≥3 ICANS was 17% and 6%, respectively. Relapse/refractory disease at day 30 and 60 post-Kymriah infusion was 11% and 16%, respectively. AlloHCT was performed in 17 (16%) patients. Median time to alloHCT from Kymriah infusion was 148 days (36-354). The median number of admissions was 1 (0-5) and median length of all hospitalization was 18 days (0-69), 99% patients required inpatient admission. Thirty-six patients (33%) required intensive care unit (ICU) admission with a median ICU stay of 5 days (1-24). The median total cost (Kymriah + inpatient cost) per patient was $615,845 ($475,000-1,578,321). Breakdown of median total cost (excluding Kymriah) was: room/board $33,676 ($0-454,256), pharmacy $65,854 ($0-515,132), laboratory/pathology cost $10,496 ($0-201,900) and other cost $8,204 ($0-573,163). One-year median cost associated with inpatient admissions for alloHCT was $556,712 ($105,670-1,919,275), combined median cost associated with Kymriah + alloHCT was $1,263,316 ($696,768-2,404,447). Factors associated with higher inpatient cost were public insurance ($96,287, p=0.002); inpatient Kymriah infusion ($395,182, p<0.001); CRS grade≥3 ($342,176, p<0.001); ICANS grade ≥3 ($354,013, p=0.010); ICU stay ($346,737 p<0.001). Multivariable analysis demonstrated that only inpatient infusion of Kymriah significantly associated with higher cost (Table 2). Conclusion: In this cost analysis across CAYA receiving Kymriah, we describe the total inpatient treatment-associated cost, with inpatient infusion emerging as a main driver of cost. With increased clinical experience, outpatient infusions and early interventions to avoid high-grade toxicity and ICU-level care have become more common and potentially more cost-effective. Our data justifies efforts to deliver Kymriah in the outpatient setting, when safe and feasible, and to provide support systems to facilitate this. Additionally, Kymriah drug cost accounts for the bulk (73%) of the overall median cost, highlighting that efforts to lower drug costs may permit enhanced access globally.

Long Term Durable Responses in Relapsed/Refractory (r/r) ALL, DLBCL, and FL Patients Treated with Tisagenlecleucel and Its Association with Persistence of CAR T-Cells

Introduction: Monitoring of chimeric antigen receptor (CAR) transgene levels in peripheral blood post tisagenlecleucel (tisa-cel) infusion provides information on expansion and persistence of CAR T-cells. In adult diffuse large B cell lymphoma (DLBCL) and follicular lymphoma (FL) patients (pts), the expansion of CAR T-cells was similar between responding and non-responding pts, while in pediatric and young adult acute lymphoblastic leukemia (ALL) pts, higher expansion in responding pts was observed. Based on long term follow up data from tisa-cel treated pts, analyses were performed to delineate the impact of CAR persistence and B cell aplasia on duration of remission (DOR). Methods: Transgene levels in blood measured by quantitative polymerase chain reaction were available from pivotal phase II studies in pts with r/r ALL (ELIANA [N=79], ENSIGN [N=64], NCT03123939 [N=69], NCT01626495 [N=60]), r/r DLBCL (JULIET [N=115]), and r/r FL (ELARA [N=97]), along with the long term follow up study (NCT02445222). The time related to loss of persistence of CAR T-cells (T loss) was defined as the time at which transgene levels first dropped below 50 transgene copies/µg DNA (approximates to lower limit of quantification (LLOQ) of the assay) after maximal expansion. Kaplan Meier analysis was performed to investigate the impact of duration of T loss and time corresponding to last quantifiable level (T last) on DOR/relapse. The impact of time to B cell recovery (>1% CD19+ B cells/WBCs or >3% CD19+ B cells/lymphocytes for ALL, and 80-616 cells/µL for DLBCL and FL), on DOR/relapse was also investigated. Results: Long term CAR persistence in tisa-cel treated pts has been observed for up to 9, 6, and 2.5 years for ALL, DLBCL, and FL pts, respectively, reflecting differing length of follow up based on initiation of trials in respective indications. Across indications, pts who lost transgene within 6 months or between 6-12 months had shorter DOR relative to pts with persistent transgene (Fig 1, ALL pts). In ALL, the median T loss was 27.4, 18.2, 9.7, and 18.0 months for ongoing complete response (CR) > 12 months, CR pts between 6-12 months, relapsed pts < 12 months, and relapsed pts > 12 months, respectively. However, of the pts who lost transgene within first 6 months, some pts maintained durable responses for ≥12 months (29%, 15%, and 50% in ALL, DLBCL, and FL, respectively). Among ALL relapsed pts, majority (17/26, 65%) of the pts with T loss < 6 months showed B cell recovery, however 6 pts had T loss at < 6 months as well as B-cell recovery but maintained response for ≥ 12 months. In ALL, Pulsipher et al.,(Blood Cancer Discov. 2022)have shown that NGS MRD within the first 6 months to 1 year post infusion may be a more reliable predictor of potential relapse than B cell recovery. The median time to B-cell recovery was 266 days in pts who relapsed/censored within 12 months but was not reached for pts with ongoing response at 12 months. On the contrary, B cell recovery seems to have no association with relapse in DLBCL or FL pts. Of the ALL pts with CAR persistence, pts with <50% morphologic blasts at any time prior to infusion of tisa-cel had longer DOR compared to pts with ≥50% blasts. This may also reflect a more resistant high risk ALL at the time of study entry or greater potential for stochastic loss of CD19 in pts with the higher disease burden. Conclusions: Long term sustained remission/response was observed in tisa-cel treated pts in the pivotal trials. The analyses demonstrate a positive association between CAR persistence and durable clinical responses across indications, however, some pts maintained durable responses despite early loss of transgene and/or early B cell recovery (< 6 months post infusion; Myers et al., J Clin Oncol. 2021). To note, in DLBCL and FL, the transgene levels in blood may not represent the levels at target sites including lymph nodes, moreover, T last and T loss are dependent on the duration of follow up, LLOQ etc. Of note, these analyses represent data from pivotal tisa-cel clinical studies with a heavily treated pt population post multiple lines of therapy including prior HSCT, and may not represent pts treated with commercial product, at earlier times post diagnosis in current studies with fewer lines of prior treatment, lower pre-infusion disease burden, and/or other CAR product. In pts with early loss of transgene, further research is needed to identify potential factors or patient characteristics resulting in durable responses.

Improved MRD Negativity Rates in Adverse Genomic Risk B-ALL Patients with Chemotherapy / Blinatumomab Induction: Experience from the Australasian Leukaemia Lymphoma Group (ALLG) ALL06/09 Studies

Introduction: Despite the benefits conferred by pediatric treatment protocols, outcomes in adolescent and young adult (AYA) acute lymphoblastic leukemia (ALL) remain inferior to children. Poor outcomes in AYA ALL have been associated with reduced tolerability of intensive cytotoxics and higher incidence of adverse risk disease. Our earlier ALLG ALL06 study demonstrated intensive pediatric induction/consolidation could be delivered in a similar time frame as in children suggesting tolerability was not a major contributor to poor outcome in AYA ALL. ALL06 established post consolidation (TP2=d79) minimal residual disease (MRD) positivity (MRD+) and high BMI was predictive of inferior disease free- and overall survival (OS). In order to improve TP2 MRD negativity (MRD-) in B-cell disease, the ALLG ALL09 study substituted standard consolidation for blinatumomab (blin) in phase I and II of a BFM-style protocol . We present the impact of blin on outcomes in genomic cohorts from ALL09 and compare these to similar cohorts from ALL06 treated with standard chemotherapy. Methods: Between Sep 2020 and Apr 2022, 55 patientswere enrolled to ALL09. Of these, 45 had appropriate samples for genomic analyses and 39/45 had an MRD marker identified. These 39 patients formed the genomic cohort presented below. Genomic subtyping was performed using whole transcriptome sequencing, MLPA, karyotype and FISH analyses, and disease was classified into genomic adverse (AR) vs standard (SR) risk based on contemporary literature classifiers. Bone marrow MRD was assessed using ASO-PCR for IGH and TCR rearrangements, at d33 post induction (TP1), and TP2 post blin consolidation. Differences in TP2 MRD were assessed, with estimated 3 yr relapse free survival (RFS) and OS calculated using the Kaplan-Meier method. Results: In the ALL09 cohort, median follow up was 629 days with 3 yr RFS 84.5% and OS 87.1%. In the genomic cohort, median follow up was 602 days with 3 yr RFS 88.8% and OS 93.2%, respectively. These compared favorably to 3 yr RFS and OS (both 67.5%) in the B-cell genomic cohort from ALL06. Between ALL09 and ALL06 there were similar proportions of AR patients (73% and 62.5%, respectively). In ALL09, the most frequent subtypes were PAX5alt (18%) and PAX5 p.P80R (11%) versus KMT2Ar and DUX4r (both 17.5%) in ALL06. In ALL09, Ph-like disease represented 13% vs 12.5% in ALL06. In the ALL09 genomic cohort, the MRD+ rate reduced between TP1 and TP2 (p< 0.001), with the reduction in the rate of positivity being more pronounced in the AR cohort (AR MRD+ TP1=85% vs AR TP2=39%; p< 0.001). In contrast, in ALL06 MRD+ in the AR cohort reduced by only 28% between TP1 and TP2 (p >0.05). This suggests a positive impact of blin consolidation in AR patients in ALL09. Despite improved AR MRD+ rates overall, not all genomic subtypes in ALL09 followed this trend (Table 1). To date, there are 5 relapses in the ALL09 cohort, 4 from the genomic cohort. Of these, 1 was hypodiploid and strikingly the remaining 3 patients harbored a TCF3 rearrangement ( TCF3r). All 4 relapses were significantly associated with MRD+ at TP2 (RFS: MRD-, 100% (n=14) vs MRD+, 71% (n=25); p= 0.013), and all were observed in the AR genomic group. Of interest, the fifth case, outside of the genomic cohort, was classified as PAX5alt. In ALL09, high-risk (HR) patients proceeded to intensive HR block chemotherapy with the aim of eliminating MRD prior to allogeneic transplant (SCT). In the genomics cohort 15 patients proceeded to HR therapy, n=12 were considered AR. Sustained MRD+ through HR blocks 1 and 2 was noted in patients harboring PAX5 p.P80R (3/3), KMT2Ar (2/2) and TCF3r (2/3). Of the 9 patients who proceeded to SCT, 3 had PAX5 p.P80R 1 had PAX5alt, 2 were KMT2Ar and there was 1 each of DUX4r, hypodiploid and TCF3r. The 3 patients who remained MRD+ in the SR cohort had PAX5 p.P80R and all 3 proceeded to SCT. Conclusion: This is the first report of the impact of blin consolidation on genomic subsets of de novo AYA ALL. Our study suggests blin sensitivity as assessed by TP2 MRD response may be genomic subtype dependent, with TCF3r associated with sustained MRD+, leading to eventual relapse (3/3 patients). In addition, the PAX5 p.P80R subset was also associated with sustained high levels of TP2 MRD+ (3/4 with an MRD marker) and SCT (3/5 patients). These results may assist with identification of AYA ALL subsets that could benefit from alternative approaches as blin becomes increasingly incorporated into front-line protocols.

The Clinicogenomic Landscape of Induction Failure in Childhood and Young Adult T-Cell Acute Lymphoblastic Leukemia.

Failure to respond to induction chemotherapy portends a poor outcome in childhood acute lymphoblastic leukemia (ALL) and is more frequent in T-cell ALL (T-ALL) than B-cell ALL. We aimed to address the limited understanding of clinical and genetic factors that influence outcome in a cohort of patients with T-ALL induction failure (IF). We studied all cases of T-ALL IF on two consecutive multinational randomized trials, UKALL2003 and UKALL2011, to define risk factors, treatment, and outcomes. We performed multiomic profiling to characterize the genomic landscape. IF occurred in 10.3% of cases and was significantly associated with increasing age, occurring in 20% of patients age 16 years and older. Five-year overall survival (OS) rates were 52.1% in IF and 90.2% in responsive patients (P < .001). Despite increased use of nelarabine-based chemotherapy consolidated by hematopoietic stem-cell transplant in UKALL2011, there was no improvement in outcome. Persistent end-of-consolidation molecular residual disease resulted in a significantly worse outcome (5-year OS, 14.3% v 68.5%; HR, 4.10; 95% CI, 1.35 to 12.45; P = .0071). Genomic profiling revealed a heterogeneous picture with 25 different initiating lesions converging on 10 subtype-defining genes. There was a remarkable abundance of TAL1 noncoding lesions, associated with a dismal outcome (5-year OS, 12.5%). Combining TAL1 lesions with mutations in the MYC and RAS pathways produces a genetic stratifier that identifies patients highly likely to fail conventional therapy (5-year OS, 23.1% v 86.4%; HR, 6.84; 95% CI, 2.78 to 16.78; P < .0001) and who should therefore be considered for experimental agents. The outcome of IF in T-ALL remains poor with current therapy. The lack of a unifying genetic driver suggests alternative approaches, particularly using immunotherapy, are urgently needed.

Blinatumomab in Combination with an Intensive Pediatric Protocol Results in High Rates of Day 79 MRD Negativity in Adolescent and Young Adult Acute Lymphoblastic Leukemia - Preliminary Results of the Australasian Leukaemia and Lymphoma Group (ALLG) ALL09 "Sublime” Study

Blinatumomab in Combination with an Intensive Pediatric Protocol Results in High Rates of Day 79 MRD Negativity in Adolescent and Young Adult Acute Lymphoblastic Leukemia - Preliminary Results of the Australasian Leukaemia and Lymphoma Group (ALLG) ALL09 "Sublime” Study

The Clinico-Genomic Landscape of Induction Failure in Childhood and Young Adult T-Cell Acute Lymphoblastic Leukemia (T-ALL)

Background T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy comprising 10-15% of childhood ALL. Previously, we found that Induction Failure (IF) occurs in approximately 10% of T-ALL cases, 3-fold more than in B-ALL, with only 50% achieving long-term survival (O'Connor et al, JCO 2017). Despite the preponderance of IF in T-ALL, little is known about the factors that predict treatment resistance and influence outcome, or how best to treat these patients. To address this, we present the largest cohort of T-ALL IF reported to date, comprising all IF cases on two large multi-national consecutive randomized trials, UKALL2003 and UKALL2011. Methods The UKALL2003 and UKALL2011 trials recruited 711 patients with T-ALL between 2004-2019; 688 of these patients were assessable at the end of induction (EOI). We supplemented existing trial data with new clinical data, and combined whole genome sequencing (WGS) and RNA-sequencing (RNAseq), to comprehensively characterize the clinical and genetic landscape of T-ALL IF. Results Of 688 T-ALL patients, 10.3% experienced IF. IF was significantly associated with increasing age occurring in 5.6% of patients below 10 years, 12.9% of those aged 10-16 years and 20% of patients over 16 years (p<0.001). Survival was significantly worse in IF (5yr Event-free survival (EFS) 47.9% (95%CI: 35.8 - 59.1) vs. 84.0% (95%CI: 80.7 - 86.8); HR:5.14 (95% CI: 2.82-6.07), p<0.001; 5yr Overall survival (OS) 52.1% (95%CI: 39.7 - 63.1) vs. 90.2% (95%CI: 87.4 - 92.5); HR: 6.38 (95% CI: 4.17-9.76), p<0.001). There was a clear trend towards increasing use of nelarabine over the study period; IF patients treated on UKALL2003 commonly remained on standard trial chemotherapy (74.2%; 26/35), while IF patients treated on the later UKALL2011 trial were more frequently treated with nelarabine and HSCT (68.6%; 24/35, p=0.0007). However, this did not translate into an improved outcome for IF patients, with no clear benefit of either HSCT or Nelarabine therapy. WGS revealed a picture of remarkable genetic heterogeneity, with 25 different initiating lesions converging on 10 subtype-defining T-ALL genes, rather than a single unifying driver of IF (Figure 1). Allocation of cases to conventional T-ALL subtypes found almost half were of the HOXA subtype, significantly more than in responsive T-ALL (p<0.001). This was consistent with immunophenotypic characterisation showing a significant enrichment of the Early T-cell precursor (ETP) subtype, present in 48% of IF cases vs. 10% of non-IF cases (p<0.001), indicating a less differentiated, more stem cell-like leukemia. Although the overall proportion of TAL1 cases was lower in IF, there was an unexpected dominance of non-coding TAL1 enhancer mutations, accounting for 87.5% of TAL1 cases. Importantly, TAL1 cases had a particularly dismal outcome with an OS of 12.5% (0.6-42.3). Notably, none of the 7 patients with a TAL1 non-coding driver lesion survived, and 2 never achieved remission, identifying this as a very high-risk genetic lesion in the context of IF. Mutational profiling found a reduction in mutations in several highly recurrent T-ALL genes (NOTCH1, FBXW7, CDKN2A, LEF1) coupled with an increase in mutations in WT1 and MED12, both of which have been associated with disease resistance in other leukemias. In addition, 2 genes not previously reported in T-ALL were recurrently mutated in IF with mutations in CHD4 in 5 cases and KAT6A in 4 cases, suggesting they may be novel drivers of refractory disease. Survival analyses also showed a significantly poorer survival in patients with mutations in MYCN and NRAS. WGS of samples collected at the end of induction showed no new lesions demonstrating that disease at presentation is representative of true refractory leukemia and that IF does not occur as a result of chemotherapy-induced mutagenesis. Conclusions Our results confirm the poor prognosis of IF in T-ALL and highlight a lack of progress in treatment of this high-risk leukemia, with no clear improvement in outcome despite increased use of nelarabine and HSCT. Genomic analyses identified a marked enrichment for non-coding TAL1 enhancer mutations, characterizing an ultra-high-risk group of patients in the context of IF, in which there were no survivors. The lack of a readily targetable pathway of primary chemoresistance supports alternative strategies, such as those employing immunotherapeutic agents. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Time to Cure for Childhood and Young Adult Acute Lymphoblastic Leukemia Is Independent of Early Risk Factors: Long-Term Follow-Up of the UKALL2003 Trial.

The aim of the randomized trial, UKALL2003, was to adjust treatment intensity on the basis of minimal residual disease (MRD) stratification for children and young adults with acute lymphoblastic leukemia. We analyzed the 10-year randomized outcomes and the time for patients to be considered cured (ClinicalTrials.gov identifier: NCT00222612). A total of 3,113 patients were analyzed including 1,054 patients who underwent random assignment (521 MRD low-risk and 533 MRD high-risk patients). Time to cure was defined as the point at which the chance of relapse was < 1%. The median follow-up time was 10.98 (interquartile range, 9.19-13.02) years, and survival rates are quoted at 10 years. In the low-risk group, the event-free survival was 91.7% (95% CI, 87.4 to 94.6) with one course of delayed intensification versus 93.7% (95% CI, 89.9 to 96.1) with two delayed intensifications (adjusted hazard ratio, 0.73; 95% CI, 0.38 to 1.40; P = .3). In the high-risk group, the event-free survival was 82.1% (95% CI, 76.9 to 86.2) with standard therapy versus 87.1% (95% CI, 82.4 to 90.6) with augmented therapy (adjusted hazard ratio, 0.68; 95% CI, 0.44 to 1.06; P = .09). Cytogenetic high-risk patients treated on augmented therapy had a lower relapse risk (22.1%; 95% CI, 15.1 to 31.6) versus standard therapy (52.4%; 95% CI, 28.9 to 80.1; P = .016). The initial risk of relapse differed significantly by sex, age, MRD, and genetics, but the risk of relapse for all subgroups quickly coalesced at around 6 years after diagnosis. Long-term outcomes of the UKALL2003 trial confirm that low-risk patients can safely de-escalate therapy, while intensified therapy benefits patients with high-risk cytogenetics. Regardless of prognosis, the time to cure is similar across risk groups. This will facilitate communication to patients and families who pose the question "When am I/is my child cured?"

Disparities in trial enrollment and outcomes of Hispanic adolescent and young adult acute lymphoblastic leukemia

AbstractIn this secondary analysis of Hispanic adolescents and young adults (AYA) with acute lymphoblastic leukemia (ALL) treated on Cancer and Leukemia Group B (CALGB) 10403, we evaluated outcomes and geographic enrollment patterns relative to US population data. We used demographic, clinical, and survival data on AYAs enrolled on CALGB 10403 (N = 295, 2007-2012). Surveillance, Epidemiology, and End Results registries provided overall survival (OS) for US AYA ALL by ethnicity/race. North American Association of Cancer Registries provided AYA ALL incidence overall and proportion among Hispanics by US state. Of AYAs enrolled on CALGB 10403, 263 (89%) reported ethnicity/race: 45 (17%) Hispanic, 172 (65%) non-Hispanic White (NHW), 25 (10%) non-Hispanic Black (NHB), and 21 (8%) other. Compared with NHWs, Hispanic and NHB patients had lower household income, and Hispanic patients were more likely to harbor high-risk CRLF2 aberrations. Relative to US estimates, where Hispanic patients represented 46% of newly diagnosed AYA ALL patients and experienced inferior OS compared with NHW (P < .001), Hispanic AYAs on CALGB 10403 did as well as NHW patients (3 year OS, 75% vs 74%; P = NS). Hispanic patients also had higher rates of protocol completion (P = .05). Enrollments on CALGB 10403 differed relative to the distribution of Hispanic AYA ALL in the United States: enrollment was highest in the Midwest; t and only 15% of enrollees were from states with a high proportion of Hispanic AYA ALL patients. In summary, Hispanic patients treated on CALGB 10403 did as well as NHWs and better than population estimates. Geographical misalignment between trial sites and disease epidemiology may partially explain the lower-than-expected enrollment of Hispanic AYA ALL patients.

Frequency of CD34 and CD10 Expression in Adolescent and Young Adult Patients Having Precursor B-cell Acute Lymphoblastic Leukemia and Its Correlation With Clinical Outcomes: A Single-Center Study.

Background: The clinical outcomes of CD34 and CD10 antigens expression in adolescent and young adult (AYA) precursor B-cell acute lymphoblastic leukemia (pre-B-ALL) is not still well established. In the present study, we analyzed the laboratory characteristics and clinical outcomes of 123 AYA pre-B-ALL patients in order to evaluate the possible clinical significance of these markers.Materials and methods: In the current study clinical data of 123 consecutive AYA pre-B-ALL patients aged 18-39 years old, enrolled in adult hematology-oncology unit from December 2014 to April 2019 was analyzed. Patient clinical outcome was calculated as overall survival and disease-free survival.Results: Overall, 76.4% of patients showed CD34 expression and CD10 expression was found in 90.2%. CD34 and CD10 expression was associated with higher total leucocyte count, increased peripheral blood blast percentage, and decreased platelet count. Overall survival and disease-free survival were both significantly better in CD34 negative and CD10 negative patients compared to their CD34 positive and CD10 positive counterparts.Interpretation and conclusion: Expressions of CD34 and CD10 are adverse prognostic factors in AYA pre-B-ALL patients and the presence of these antigens influences the clinical outcome of these patients.

The current approach and the treatment of adolescents and young adults with acute lymphoblastic leukemia

Introduction. The treatment outcome of adolescents and young adults with acute lymphoblastic leukemia is much poorer in contrast to pediatric patients. By changing the concept of the treatment for patients who are adolescents and young adults with acute lymphoblastic leukemia, especially with the use of pediatric regimens, significant improvement in survival has been made (current 5-year survival rate goes up to 70%). Contributing factors for different outcomes between children and adolescents and young adults with acute lymphoblastic leukemia. Beside the differences between pediatric and adult protocols, there are several factors which can explain the different outcomes between these groups of patients with acute lymphoblastic leukemia. One of the main factors is different biology of the leukemias and, on the other side, lower accrual rates in clinical trials in adolescents and young adults and their specific psychosocial factors, like poor compliance with the treatment and missed appointments. Current treatment and novel approaches in the treatment of adolescents and young adults with acute lymphoblastic leukemia. Current treatment approach to the adolescent and young adults with acute lymphoblastic leukemia is based on the pediatric protocols with the risk-adapted strategy, which depends primarily on the cytogenetics and postinduction minimal/measurable residual disease. The main goal of the novel treatment, especially with the use of targeted therapy and innovative immunotherapies incorporated in the pediatric protocols, is to achieve a deep and durable leukemia-free survival. To transplant or not to transplant adolescents and young adults with acute lymphoblastic leukemia is still a matter of debate, particularly in the era of pediatric regimens and the new sequence algorithm with the upfront use of novel drugs. Conclusion. Adolescent and young adult patients with acute lymphoblastic leukemia should be treated in specialized centers by an experienced multidisciplinary team with close attention to their particular needs.

An MRD-stratified pediatric protocol is as deliverable in adolescents and young adults as in children with ALL

AbstractPediatric regimens have improved outcomes in adolescent and young adult (AYA) acute lymphoblastic leukemia (ALL). However, results remain inferior to children with ALL. The Australasian Leukaemia and Lymphoma Group (ALLG) ALL06 study (anzctr.org.au/ACTRN12611000814976) was designed to assess whether a pediatric ALL regimen (Australian and New Zealand Children's Haematology and Oncology Group [ANZCHOG] Study 8) could be administered to patients aged 15 to 39 years in a comparable time frame to children as assessed by the proportion of patients completing induction/consolidation and commencing the next phase of therapy (protocol M or high-risk [HR] treatment) by day 94. Minimal residual disease (MRD) response stratified patients to HR treatment and transplantation. From 2012 to 2018, a total of 86 patients were enrolled; 82 were eligible. Median age was 22 years (range, 16-38 years). Induction/consolidation was equally deliverable in ALL06 as in Study 8. In ALL06, 41.5% (95% confidence interval [CI], 30.7-52.9) commenced protocol M or HR therapy by day 94 vs 39.3% in Study 8 (P = .77). Median time to protocol M/HR treatment was 96 days (interquartile range, 87.5-103 days) in ALL06 vs 98 days in Study 8 (P = .80). Induction mortality was 3.6%. With a median follow-up of 44 months (1-96 months), estimated 3-year disease-free survival was 72.8% (95% CI, 62.8-82.7), and estimated 3-year overall survival was 74.9% (95% CI, 65.3-84.5). End induction/consolidation MRD negativity rate was 58.6%. Body mass index ≥30 kg/m2 and day 79 MRD positivity were associated with poorer disease-free survival and overall survival. Pediatric therapy was safe and as deliverable in AYA patients as in children with ALL. Intolerance of pediatric ALL induction/consolidation is not a major contributor to inferior outcomes in AYA ALL.

MCL-1 Inhibition Overcomes Anti-apoptotic Adaptation to Targeted Therapies in B-Cell Precursor Acute Lymphoblastic Leukemia.

Multiple targeted therapies are currently explored for pediatric and young adult B-cell precursor acute lymphoblastic leukemia (BCP-ALL) treatment. However, this new armamentarium of therapies faces an old problem: choosing the right treatment for each patient. The lack of predictive biomarkers is particularly worrying for pediatric patients since it impairs the implementation of new treatments in the clinic. In this study, we used the functional assay dynamic BH3 profiling (DBP) to evaluate two new treatments for BCP-ALL that could improve clinical outcome, especially for relapsed patients. We found that the MEK inhibitor trametinib and the multi-target tyrosine kinase inhibitor sunitinib exquisitely increased apoptotic priming in an NRAS-mutant and in a KMT2A-rearranged cell line presenting a high expression of FLT3, respectively. Following these observations, we sought to study potential adaptations to these treatments. Indeed, we identified with DBP anti-apoptotic changes in the BCL-2 family after treatment, particularly involving MCL-1 – a pro-survival strategy previously observed in adult cancers. To overcome this adaptation, we employed the BH3 mimetic S63845, a specific MCL-1 inhibitor, and evaluated its sequential addition to both kinase inhibitors to overcome resistance. We observed that the metronomic combination of both drugs with S63845 was synergistic and showed an increased efficacy compared to single agents. Similar observations were made in BCP-ALL KMT2A-rearranged PDX cells in response to sunitinib, showing an analogous DBP profile to the SEM cell line. These findings demonstrate that rational sequences of targeted agents with BH3 mimetics, now extensively explored in clinical trials, may improve treatment effectiveness by overcoming anti-apoptotic adaptations in BCP-ALL.

Impact of Humoral Immunogenicity (Anti-mCAR19 Antibodies) on CTL019 Cellular Kinetics, Efficacy, and Safety

Background: The humoral immunogenicity of CAR19, a chimeric antigen receptor with a murine scFV domain developed for treatment with CTL019 (tisagenlecleucel) in relapsed/refractory (R/R) pediatric and young adult acute lymphoblastic leukemia (ALL), was evaluated in 2 studies (ELIANA [NCT02435849]; ENSIGN [NCT02228096]). To date, little is known about the presence and impact of preexisting or treatment-induced anti-murine (m)CAR19 antibodies in patients treated with CAR T-cell therapy.Methods: Anti-mCAR19 antibodies were measured in patients from ELIANA and ENSIGN trials before and after CTL019 infusion to evaluate the impact of anti-mCAR19 antibodies on cellular kinetics, efficacy, and safety. Data were pooled from ELIANA (n = 68) and ENSIGN (n = 29). Anti-mCAR19 antibodies were captured by mCAR19-transfected Jurkat cells and wild-type Jurkat cells. Following incubation and washing, an R-phycoerythrin (PE)-labeled anti-IgG/M F(ab')2 fragment was added for detection of anti-mCAR19 antibodies using flow cytometry and reported as median fluorescence intensity (MFI). Exploratory assay development included assessment of whether the presence of immunoglobulins after IVIG therapy in clinical samples would interfere with the anti-mCAR19 antibody assay. Impact of preexisting immunogenicity, as detected by MFI levels, was evaluated using cellular kinetic, efficacy, and safety endpoints. The impact of treatment-induced immunogenicity (defined as having an increase in anti-mCAR19 antibody levels over baseline) was assessed by calculating the fold change between preexisting (ie, baseline) levels and postinfusion levels.Results: Approximately 90% of patients displayed preexisting anti-mCAR19 antibodies; a similar incidence was detected in healthy volunteer samples, as observed during assay development. Approximately 35% of patients developed treatment-induced anti-mCAR19 antibodies. No apparent relationship between CTL019 expansion (AUC0-28d) and preexisting or treatment-induced anti-mCAR19 antibodies was identified (r2 < 0.001 and r2 = 0.006, respectively); similar results were seen for Cmax (Figure 1a). Presence of anti-mCAR19 after infusion did not appear to influence the persistence of transgene or day 28 response (Figure 1b). Kaplan-Meier curves showed that the presence of preexisting and treatment-induced anti-mCAR19 antibodies did not appear to impact the duration of response or event-free survival (Figure 1c). Strip plots showed consistent levels of preexisting and treatment-induced anti-mCAR19 antibodies across patients with safety events (grade 0/1/2/3/4), including CRS, neutropenia, thrombocytopenia, and neurological events. There was no apparent relationship between treatment- induced anti-mCAR19 antibodies with B-cell recovery categories (recovery ≤ 3 months, > 3 months and ≤ 6 months, > 6 months, and ongoing sustained B-cell aplasia). There was also no association in patients at the time of B-cell recovery with the presence of treatment-induced anti-mCAR19 antibodies following CTL019 infusion. B-cell aplasia requiring immunoglobulin replacement therapy (IVIG) occurred following CTL019 in the majority of patients. The CTL019 concentration time profiles for patients with treatment-induced anti-mCAR19 antibodies were categorized by the time following IVIG administration (within 1 week, 2 weeks, or > 3 weeks of IVIG administration). The results revealed no impact of the time at which IVIG was administered on the in vivo expansion and persistence of the transgene.Conclusions: We report the first comprehensive assessment of the impact of anti-mCAR antibodies on clinically relevant endpoints for CAR therapy. Determination of immunogenicity is an important endpoint required by health authorities for biologic drugs, and these analyses demonstrate the importance of characterizing the impact on clinical endpoints for CAR therapies. These analyses in patients with pediatric R/R ALL revealed a surprisingly high frequency of baseline anti-mCAR19 antibodies and showed that the presence of preexisting and treatment-induced anti-mCAR19 antibodies did not impact the cellular kinetics, safety, and efficacy of CTL019. Cell-mediated immunity studies are ongoing. [Display omitted] DisclosuresMueller:Novartis Pharmaceuticals Corporation: Employment. Waldron:Novartis Pharmaceuticals Corporation: Employment. Sickert:Novartis Institutes for BioMedical Research: Employment. Grupp:University of Pennsylvania: Patents & Royalties; Novartis Pharmaceuticals Corporation: Consultancy, Other: grant; Adaptimmune: Consultancy; Jazz Pharmaceuticals: Consultancy. Maude:Novartis Pharmaceuticals: Consultancy, Other: Medical Advisory Boards. Levine:Novartis Pharmaceuticals Corporation: Membership on an entity's Board of Directors or advisory committees. Laetsch:Novartis Pharmaceuticals Corporation: Consultancy. Pulsipher:Novartis Pharmaceuticals Corporation: Consultancy, Other: Phase II steering committee; Chimerix: Other: Advisory board Dec 2015; Jazz Pharmaceuticals: Other: advisory board, education; CSL Behring: Other: advisory board Feb 2017; Adaptive: Other: Advisory board 6/17. Boyer:Novartis Pharmaceuticals Corporation: Honoraria. August:Novartis Pharmaceuticals Corporation: Consultancy. Awasthi:Novartis Pharmaceuticals Corporation: Employment. Levine:GE Healthcare: Consultancy; Novartis Pharmaceuticals Corporation: Patents & Royalties, Research Funding; Brammer Bio: Consultancy; Tmunity Therapeutics: Equity Ownership, Research Funding. June:WIRB/Copernicus Group: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celldex: Honoraria, Membership on an entity's Board of Directors or advisory committees; Immune Design: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Novartis: Patents & Royalties, Research Funding; Tmunity Therapeutics: Equity Ownership, Research Funding. Taran:Novartis Pharmaceuticals Corporation: Employment, Equity Ownership. Wood:Novartis Pharmaceuticals Corporation: Employment, Equity Ownership. Myers:Novartis Pharmaceuticals Corporation: Consultancy.

Metabolic and Endocrin Complications of Pediatric, Adolescent and Young Adult Acute Lymphoblastic Leukemia: Single Centre Experience

Introduction: Metabolic and endocrine complications are common complications in the treatment of Acute Lymphoblastic Leukemia (ALL). Inappropriate anti-diuretic hormone (ADH) syndrome, diabetes mellitus, hypoglycemia, surrenal failure, hypercalcemia may ocur during the treatment. Obesity, growth retardation or pause and osteopenia are the most common complications. These complications are usually due to combined chemotherapeutic agents used during the treatment. In this study, we present the metabolic/endocrine complications which are observed during treatment of ALL patients at our center.Material -Metod: One hundred and ten patients who were diagnosed with ALL and treated with the ‘Children's Oncology Group’ (COG) protocol and follow-up in the Pediatric Hematology / Oncology Department of the Istanbul University Institute of Oncology were included in the study. We retrospectively analyzed the demographic characteristics of the patients and presence of metabolic/endocrin problems (hyperglycemia, hypoglycemia, hypothyroidism, hypercholesterolemia, obesity) during all treatment stages were recorded. Forty-five (40.9%) of the patients were female and 65 (59.1%) were male. Ninety-seven (88.2%) patients were pre-B-cell ALL, 1 (0.9%) patients were mature B-cell ALL, 11 (10%) patients were T-cell ALL and 1 (0.9%) patients were biphenotypic ALL. The median age of the patients were 7 years (range:1,5-23).Results: One hundred of the 110 patients whose all clinical data were obtained were included for the evaluation of the metabolic and endocrin complications. The metabolic and endocrine problems were detected in 16 (16%) patients in any phases of the treatment and 84 (84%) patients did not have any metobolic or endocrine problems during the treatment. Twelve (12%) of the 16 patients with metabolic and endocrine problems were in 1 phase and 4 (4%) in 2 phases. Totally, 23 problems were detected. All metabolic / endocrine problems that arise during treatment are shown in Table 1. Seven of them (30.4%) were in induction, 2 of them were in consolidation (8.8%), no problems were found in interim maintenance 1, 7 (30.4%) were in delayed intencification, Interim maintenance 2 and delayed intencification 2 did not show any problems, and 7 (30.4%) were seen in maintenance.Conclusion: In the treatment of ALL, endocrine and metabolic problems are frequently seen during and after treatment. In our study, 23 metabolic problems (hyperglycemia, hypoglycemia, hypothyroidism, hypertriglyceridemia, hypercholesterolemia, osteoporosis, obesity, hyperferritinemia, metabolic syndrome) were recorded in 16 (16%) of the patients. Our resuts suggest that metabolic complications that may occur in ALL treatment should be considered as well as the remission of the disease. Therefore, patients should be carefully evaluated for metabolic and endocrin problems in ALL treatment. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

High Expression of MEF2D-Fusion Protein Is Caused By Escaping from the Suppression By miRNA and Leads to Suppress Transcriptional Activity of PAX5

We previously discovered new fusion genes, MEF2D-BCL9 and MEF2D-HNRNPUL1, in 9% of adolescent and young adult B-cell acute lymphoblastic leukemia (ALL; Yasuda T, et al. , Nature Genetics, 2016;48:569-574). Vector driving expression of MEF2D-fusion protein was markedly higher than the expression of wild-type MEF2D (MEF2D W) protein driven by the same expression vector system; however, the mechanism and significance of the high-expression have been yet to be clarified.We first confirmed fusion specific MEF2D high expression was occurred in MEF2D fusion-positive ALL cell lines, Kasumi-7 and Kasumi-9. Protein half-life and the effect of proteasome inhibitor on protein expression were not significantly different between MEF2D W and MEF2D-fusion, suggesting that stability of protein was not different between them. We speculated that MEF2D fusion gene lost the miRNA target that existed in C-terminal half of MEF2D mRNA and that the high-expression of MEF2D fusion protein was caused by escaping from the suppression by miRNA (Figure A). In order to investigate this speculation, we made several expression vectors of MEF2D that express same partial MEF2D protein but transcript different length of mRNA. That is, we introduced a mutation substituting stop codon for D336, the breakpoint of MEF2D-HNRNPUL1 fusion protein, into the expression vector of wild-type MEF2D and designated it as MEF2D (full D336Stop). We deleted C-terminal legion from it with various lengths (Figure B). The protein expression level of MEF2D (1-335) from MEF2D (full D336Stop) vector was similar to that of MEF2D W; however, the protein expression level was markedly increased when DNA region coding amino acid (aa) 377-418 was deleted from the expression vector (Figure C), indicating that protein expression of MEF2D (1-335) was down regulated by miRNA targeting mRNA coding aa 377-418. We identified a candidate of responsible miRNA by database search. Transfection of miRNA mimic of the candidate miRNA decreased the protein expression of MEF2D W but not that of MEF2D fusion. Introduction of mutation at the binding site of the candidate miRNA increased the protein expression of MEF2D W. We examined the effect of MEF2D fusion protein on transcriptional activity of various B cell differentiation regulators and found that MEF2D-fusion protein suppressed transcriptional activity of PAX5 in luciferase assays in dose-dependent manner and that MEF2D W protein did not significantly affect it. These results suggested that the high-expression of MEF2D fusion protein impaired B cell differentiation through the inhibition of PAX5 function. This is the first report that a mutation of a coding gene causes high expression of the protein coded by the gene through escape from suppression by miRNA. These results shed a new insight into the mechanism of leukemia development by MEF2D fusion gene and pathological significance of miRNA-related disorder. [Display omitted] DisclosuresNaoe:Otsuka Pharmaceutical Co.,Ltd.: Honoraria, Research Funding; Nippon Boehringer Ingelheim Co.: Honoraria, Research Funding; Fujifilm Corporation: Patents & Royalties, Research Funding; Dainippon Sumitomo Pharma Co.,LTD.: Research Funding; Astellas Pharma Inc.: Research Funding; Toyama Chemikal Co.,Ltd.: Research Funding. Kiyoi:Bristol-Myers Squibb: Honoraria, Research Funding; Nippon Shinyaku Co., Ltd.: Research Funding; Meiji Seika Pharma Co.,Ltd.: Research Funding; Zenyaku Kogyo Co., Ltd.: Research Funding; MSD K.K.: Research Funding; Celgene Corporation: Consultancy, Research Funding; Kyowa Hakko Kirin Co., Ltd.: Research Funding; Chugai Pharmaceutical Co., Ltd.: Research Funding; Eisai Co., Ltd.: Research Funding; Sumitomo Dainippon Pharma Co., Ltd.: Research Funding; Nippon Boehringer Ingelheim Co., Ltd.: Research Funding; Astellas Pharma Inc.: Consultancy, Research Funding; JCR Pharmaceuticals Co.,Ltd.: Research Funding; Novartis Pharma K.K.: Research Funding; FUJIFILM Corporation: Patents & Royalties, Research Funding; ONO Pharmaceutical Co., Ltd.: Research Funding; Phizer Japan Inc.: Honoraria, Research Funding; Takeda Pharmaceutical Co., Ltd.: Research Funding.

Outcomes and prognostic factors in adolescents and young adults with ALL treated with a modified BFM-90 protocol

AbstractThe use of pediatrics-inspired protocols in adolescent and young adult (AYA) acute lymphoblastic leukemia (ALL) results in superior survival compared with the adult protocols. Pediatrics-inspired protocols carry an increased risk of toxicity and treatment-related mortality in low resource settings, which can offset the potential benefits. We studied the outcomes and prognostic factors in the treatment of AYA ALL with a pediatrics-inspired regimen. We retrieved data regarding demographics, investigations, treatment details, and toxicities from the electronic medical records of patients diagnosed with ALL in the 15- to 25-year-old age group who were initiated on a modified Berlin-Frankfurt-Münster 90 (BFM-90) protocol between January 2013 and December 2016 at the Tata Memorial Centre. A total of 349 patients in the 15- to 25-year-old age group were treated with a modified BFM-90 protocol. The use of this pediatrics-inspired protocol resulted in a 3-year event-free survival (EFS) and overall survival (OS) of 59.4% and 61.8%, respectively. Only 15 patients underwent an allogeneic stem cell transplant. Minimal residual disease (MRD) persistence postinduction emerged as the only factor predictive of poor outcomes. A modified BFM-90 protocol is an effective and safe regimen for AYA ALL with an OS and EFS comparable to the published literature.

241 - Predictive Value of Next-Generation Sequencing (NGS) Following Tisagenlecleucel in Pediatric and Young Adult B-Cell Acute Lymphoblastic Leukemia

241 - Predictive Value of Next-Generation Sequencing (NGS) Following Tisagenlecleucel in Pediatric and Young Adult B-Cell Acute Lymphoblastic Leukemia