Treatment completion, asparaginase completion, and oncologic outcomes among children, adolescents and young adults with acute lymphoblastic leukemia treated with DFCI Consortium Protocols.

Adolescents and young adult (AYA) patients with acute lymphoblastic leukemia (ALL) face worse outcomes than children. While pediatric-inspired protocols have improved outcomes, the ability of patients to complete these intensive regimens and the reasons for discontinuation are unknown. We analyzed a cohort of 332 AYA patients (aged 15-49 years) and 1159 children (aged 1-14 years) with Ph-negative ALL treated on DFCI consortium protocols. We found that AYA patients completed treatment at lower rates than children (60.8% vs. 89.7%, p < 0.001), primarily due to higher rates of early treatment failure (14.5% vs. 2.4%, p < 0.001). Withdrawal from treatment for toxicity, social/personal, or unknown reasons was uncommon, but higher among AYA patients (9.3% vs 4.7%, p = 0.001). Patients who remained on assigned therapy for one year had favorable overall survival (AYA 5-year OS 88.9%; children 5-year OS 96.4%; p < 0.001). Among patients who continued treatment for 1 year, AYA patients completed asparaginase (defined as receiving 26+ weeks) at lower rates than children (79.1% vs. 89.6%, p < 0.001). Patients who received more weeks of consolidation asparaginase had higher overall and event-free survival. Efforts should focus on identifying patients at risk for early treatment failure and optimizing asparaginase delivery.

Dasatinib with intensive chemotherapy in de novo paediatric Philadelphia chromosome-positive acute lymphoblastic leukaemia (CA180-372/COG AALL1122): a single-arm, multicentre, phase 2 trial.

BACKGROUND: The outcome of children with Philadelphia chromosome-positive (Ph-positive) acute lymphoblastic leukaemia significantly improved with the combination of imatinib and intensive chemotherapy. We aimed to investigate the efficacy of dasatinib, a second-generation ABL-class inhibitor, with intensive chemotherapy in children with newly diagnosed Ph-positive acute lymphoblastic leukaemia. METHODS: CA180-372/COG AALL1122 was a joint Children's Oncology Group (COG) and European intergroup study of post-induction treatment of Ph-positive acute lymphoblastic leukaemia (EsPhALL) open-label, single-arm, phase 2 study. Eligible patients (aged >1 year to <18 years) with newly diagnosed Ph-positive acute lymphoblastic leukaemia and performance status of at least 60% received EsPhALL chemotherapy plus dasatinib 60 mg/m2 orally once daily from day 15 of induction. Patients with minimal residual disease of at least 0·05% after induction 1B or who were positive for minimal residual disease after the three consolidation blocks were classified as high risk and allocated to receive haematopoietic stem-cell transplantation (HSCT) in first complete remission. The remaining patients were considered standard risk and received chemotherapy plus dasatinib for 2 years. The primary endpoint was the 3-year event-free survival of dasatinib plus chemotherapy compared with external historical controls. The trial was considered positive if one of the following conditions was met: superiority over chemotherapy alone in the AIEOP-BFM 2000 high-risk group; or non-inferiority (with a margin of -5%) or superiority to imatinib plus chemotherapy in the EsPhALL 2010 cohort. All participants who received at least one dose of dasatinib were included in the safety and efficacy analyses. This trial was registered with ClinicalTrials.gov, NCT01460160, and recruitment is closed. FINDINGS: Between March 13, 2012, and May 27, 2014, 109 patients were enrolled at 69 sites (including 51 COG sites in the USA, Canada, and Australia, and 18 EsPhALL sites in Italy and the UK). Three patients were ineligible and did not receive dasatinib. 106 patients were treated and included in analyses (49 [46%] female and 57 [54%] male; 85 [80%] White, 13 [12%] Black or African American, five [5%] Asian, and three [3%] other races; 24 [23%] Hispanic or Latino ethnicity). All 106 treated patients reached complete remission; 87 (82%) were classified as standard risk and 19 (18%) met HSCT criteria and were classified as high risk, but only 15 (14%) received HSCT in first complete remission. The 3-year event-free survival of dasatinib plus chemotherapy was superior to chemotherapy alone (65·5% [90% Clopper-Pearson CI 57·7 to 73·7] vs 49·2% [38·0 to 60·4]; p=0·032), and was non-inferior to imatinib plus chemotherapy (59·1% [51·8 to 66·2], 90% CI of the treatment difference: -3·3 to 17·2), but not superior to imatinib plus chemotherapy (65·5% vs 59·1%; p=0·27). The most frequent grade 3-5 adverse events were febrile neutropenia (n=93) and bacteraemia (n=21). Nine remission deaths occurred, which were due to infections (n=5), transplantation-related (n=2), due to cardiac arrest (n=1), or had an unknown cause (n=1). No dasatinib-related deaths occurred. INTERPRETATION: Dasatinib plus EsPhALL chemotherapy is safe and active in paediatric Ph-positive acute lymphoblastic leukaemia. 3-year event-free survival was similar to that of previous Ph-positive acute lymphoblastic leukaemia trials despite the limited use of HSCT in first complete remission. FUNDING: Bristol Myers Squibb.

Effect of BMI on toxicities and survival among adolescents and young adults treated on DFCI Consortium ALL trials.

Adolescent and young adults (AYAs) with acute lymphoblastic leukemia (ALL) treated with asparaginase-containing pediatric regimens are commonly overweight or obese. We studied the association of body mass index (BMI) on outcomes of 388 AYAs aged 15 to 50 years treated on Dana-Farber Cancer Institute (DFCI) consortium regimens (2008-2021). BMI was normal in 207 (53.3%) and overweight/obese in 181 (46.7%). Patients who were overweight or obese experienced higher nonrelapse mortality (NRM; 4-year, 11.7% vs 2.8%, P = .006), worse event-free survival (4-year, 63% vs 77%, P = .003), and worse overall survival (OS; 4-year, 64% vs 83%, P = .0001). Because younger (aged 15-29 years) AYAs more frequently had a normal BMI (79% vs 20%, P < .0001), we conducted separate analyses in each BMI group. We found excellent OS among younger and older (30-50 years) AYAs with normal BMI (4-year OS, 83% vs 85%, P = .89). Conversely, in AYAs who were overweight/obese, worse outcomes were seen in older AYAs (4-year OS, 55% vs 73%, P = .023). Regarding toxicity, AYAs who were overweight/obese experienced higher rates of grade 3/4 hepatotoxicity and hyperglycemia (60.7% vs 42.2%, P = .0005, and 36.4% vs 24.4%, P = .014, respectively) but had comparable rates of hypertriglyceridemia (29.5% vs 24.4%, P = .29). In a multivariable analysis, higher BMI was associated with worse OS, hypertriglyceridemia was associated with improved OS, and age was not associated with OS. In conclusion, among AYAs treated on DFCI Consortium ALL regimens, elevated BMI was associated with increased toxicity, increased NRM, and decreased OS. The deleterious effect of elevated BMI was more pronounced in older AYAs.

Impairment of health-related quality of life for children with acute lymphoblastic leukemia over the first year of therapy: A report from the DFCI ALL Consortium.

BACKGROUND: Children treated for acute lymphoblastic leukemia (ALL) receive prolonged treatment, resulting in toxicities that affect health-related quality of life (HR-QoL). Longitudinal assessment of HR-QoL allows improved understanding of experiences with ALL. PROCEDURE: Parent-proxy and child self-report HR-QoL over the first year of chemotherapy were evaluated in the context of DFCI Protocol 05-001, a phase 3 therapeutic trial for childhood ALL. HR-QoL was assessed with the Pediatric Quality-of-Life inventory (PedsQL) domains for Pain and Hurt, Procedural Anxiety, Treatment Anxiety, Emotional Functioning, General Fatigue, and Sleep/Rest Fatigue. RESULTS: Total of 281 subjects participated, with 141 contributing at least one child report and 280 at least one parent report. Children with ALL experienced impairment in HR-QoL by both patient and parent report compared to the published PedsQL reference population at each time point on each subscale. Agreement between parent and child assessment of HR-QoL impairment was high, particularly among those for whom HR-QoL was not impaired. During the consolidation phase, which included intensive asparaginase administration, multivariable models demonstrated more impairment in Treatment Anxiety and Procedural Anxiety for children treated with intramuscular asparaginase than intravenous asparaginase, but randomized groups were otherwise similar in HR-QoL. Impairments in fatigue, both General and Sleep/Rest, were evident throughout and worse during intensive asparaginase therapy. CONCLUSIONS: This report examines HR-QoL for children with ALL during treatment longitudinally by parent and patient report across multiple domains. Children with ALL demonstrated substantial impairment in HR-QoL, particularly related to fatigue during intensive consolidation therapy including asparaginase.

Outlier Expression of Isoforms by Targeted or Total RNA Sequencing Identifies Clinically Significant Genomic Variants in Hematolymphoid Tumors.

Recognition of aberrant gene isoforms due to DNA events can impact risk stratification and molecular classification of hematolymphoid tumors. In myelodysplastic syndromes, KMT2A partial tandem duplication (PTD) was one of the top adverse predictors in the International Prognostic Scoring System-Molecular study. In B-cell acute lymphoblastic leukemia (B-ALL), ERG isoforms have been proposed as markers of favorable-risk DUX4 rearrangements, whereas deletion-mediated IKZF1 isoforms are associated with adverse prognosis and have been extended to the high-risk IKZF1plus signature defined by codeletions, including PAX5. In this limited study, outlier expression of isoforms as markers of IKZF1 intragenic or 3' deletions, DUX4 rearrangements, or PAX5 intragenic deletions were 92.3% (48/52), 90% (9/10), or 100% (9/9) sensitive, respectively, and 98.7% (368/373), 100% (35/35), or 97.1% (102/105) specific, respectively, by targeted RNA sequencing, and 84.0% (21/25), 85.7% (6/7), or 81.8% (9/11) sensitive, respectively, and 98.2% (109/111), 98.4% (127/129), or 98.7% (78/79) specific, respectively, by total RNA sequencing. Comprehensive split-read analysis identified expressed DNA breakpoints, cryptic splice sites associated with IKZF1 3' deletions, PTD of IKZF1 exon 5 spanning N159Y in B-ALL with mutated IKZF1 N159Y, and truncated KMT2A-PTD isoforms. Outlier isoforms were also effective targeted RNA markers for PAX5 intragenic amplifications (B-ALL), KMT2A-PTD (myeloid malignant cancers), and rare NOTCH1 intragenic deletions (T-cell acute lymphoblastic leukemia). These findings support the use of outlier isoform analysis as a robust strategy for detecting clinically significant DNA events.

Disparities in parental distress in a multicenter clinical trial for pediatric acute lymphoblastic leukemia.

BACKGROUND: Parent psychological distress during childhood cancer treatment has short- and long-term implications for parent, child, and family well-being. Identifying targetable predictors of parental distress is essential to inform interventions. We investigated the association between household material hardship (HMH), a modifiable poverty-exposure defined as housing, food, or utility insecurity, and severe psychological distress among parents of children aged 1-17 years with acute lymphoblastic leukemia (ALL) enrolled on the multicenter Dana-Farber ALL Consortium Trial 16-001. METHODS: This was a secondary analysis of parent-reported data. Parents completed an HMH survey within 32 days of clinical trial enrollment (T0) and again at 6 months into therapy (T1). The primary exposure was HMH at T0 and primary outcome was severe parental distress at T0 and T1, defined as a score greater than or equal to 13 on the Kessler-6 Psychological Distress Scale. Multivariable models were adjusted for ALL risk group and single parent status. RESULTS: Among 375 evaluable parents, one-third (32%; n = 120/375) reported HMH at T0. In multivariable analyses, T0 HMH was associated with over twice the odds of severe psychological distress at T0 and T1 HMH was associated with over 5 times the odds of severe distress at T1. CONCLUSIONS: Despite uniform clinical trial treatment of their children at well-resourced pediatric centers, HMH-exposed parents-compared with unexposed parents-experienced statistically significantly increased odds of severe psychological distress at the time of their child's leukemia diagnosis, which worsened 6 months into therapy. These data identify a high-risk parental population who may benefit from early psychosocial and HMH-targeted interventions to mitigate disparities in well-being.

A systems approach points to a therapeutic role for retinoids in asparaginase-associated pancreatitis.

Among drug-induced adverse events, pancreatitis is life-threatening and results in substantial morbidity. A prototype example is the pancreatitis caused by asparaginase, a crucial drug used to treat acute lymphoblastic leukemia (ALL). Here, we used a systems approach to identify the factors affecting asparaginase-associated pancreatitis (AAP). Connectivity Map analysis of the transcriptomic data showed that asparaginase-induced gene signatures were potentially reversed by retinoids (vitamin A and its analogs). Analysis of a large electronic health record database (TriNetX) and the U.S. Federal Drug Administration Adverse Events Reporting System demonstrated a reduction in AAP risk with concomitant exposure to vitamin A. Furthermore, we performed a global metabolomic screening of plasma samples from 24 individuals with ALL who developed pancreatitis (cases) and 26 individuals with ALL who did not develop pancreatitis (controls), before and after a single exposure to asparaginase. Screening from this discovery cohort revealed that plasma carotenoids were lower in the cases than in controls. This finding was validated in a larger external cohort. A 30-day dietary recall showed that the cases received less dietary vitamin A than the controls did. In mice, asparaginase administration alone was sufficient to reduce circulating and hepatic retinol. Based on these data, we propose that circulating retinoids protect against pancreatic inflammation and that asparaginase reduces circulating retinoids. Moreover, we show that AAP is more likely to develop with reduced dietary vitamin A intake. The systems approach taken for AAP provides an impetus to examine the role of dietary vitamin A supplementation in preventing or treating AAP.

"There's no playbook for when your kid has cancer": Desired elements of an electronic resource to support pediatric cancer communication.

INTRODUCTION: Acute lymphoblastic leukemia (ALL), the most common childhood malignancy, has a relatively favorable long-term prognosis. Yet the complexity of treatment and the emotionality of the diagnosis leave families feeling unprepared for many aspects of therapy. This qualitative study aimed to identify desired elements and format of a communication resource to support patients and families facing a diagnosis of ALL. METHODS: Semi-structured interviews of 12 parents of children receiving ALL treatment, 10 parents of survivors of ALL, and eight adolescent and young adult (AYA) survivors of ALL were conducted between February and June 2021. The interviews focused on communication experiences throughout treatment and identified domains to be addressed in a resource in development. RESULTS: All participants supported the development of an interactive, electronic health (eHealth) resource to help navigate ALL treatment. They felt a website would be helpful in addressing information gaps and mitigating pervasive feelings of overwhelm. Participants specifically sought: (a) information resources to address feelings of cognitive overload; (b) practical tips to help navigate logistical challenges; (c) clear depictions of treatment choices and trajectories to facilitate decision-making; and (d) additional psychosocial resources and support. Two overarching themes that families felt should be interwoven throughout the eHealth resource were connections with other patients/families and extra support at transitions between phases of treatment. CONCLUSIONS: A new diagnosis of ALL and its treatment are extremely overwhelming. Patients and families unanimously supported an eHealth resource to provide additional information and connect them with emotional support, starting at diagnosis and extending throughout treatment.

Feasibility of serial neurocognitive assessment using Cogstate during and after therapy for childhood leukemia.

PURPOSE: Neurocognitive impairment is frequently observed among survivors of childhood acute lymphoblastic leukemia (ALL) within the domains of attention, working memory, processing speed, executive functioning, and learning and memory. However, few studies have characterized the trajectory of treatment-induced changes in neurocognitive function beginning in the first months of treatment, to test whether early changes predict impairment among survivors. If correct, we hypothesize that those children who are most susceptible to early impairment would be ideal subjects for clinical trials testing interventions designed to protect against treatment-related neurocognitive decline. METHODS: In this pilot study, we prospectively assessed neurocognitive functioning (attention, working memory, executive function, visual learning, and processing speed), using the Cogstate computerized battery at six time points during the 2 years of chemotherapy treatment and 1-year post-treatment (Dana-Farber Cancer Institute ALL Consortium protocol 11-001; NCT01574274). RESULTS: Forty-three patients with ALL consented to serial neurocognitive testing. Of the 31 participants who remained on study through the final time point, 1 year after completion of chemotherapy, 28 (90%) completed at least five of six planned Cogstate testing time points. Performance and completion checks indicated a high tolerability (≥ 88%) for all subtests. One year after completion of treatment, 10 of 29 patients (34%) exhibited neurocognitive function more than 2 standard deviations below age-matched norms on one or more Cogstate subtests. CONCLUSIONS: Serial collection of neurocognitive data (within a month of diagnosis with ALL, during therapy, and 1-year post-treatment) is feasible and can be informative for evaluating treatment-related neurocognitive impairment.

Nelarabine combination therapy for relapsed or refractory T-cell acute lymphoblastic lymphoma/leukemia.

Nelarabine, an antimetabolite prodrug, is approved as monotherapy for children and adults with relapsed and refractory T-cell acute lymphoblastic leukemia and lymphoma (R/R T-ALL/LBL), although it is often used in combination regimens. We sought to understand differences in efficacy and toxicity when nelarabine is administered alone or in combination. We retrospectively analyzed 44 consecutive patients with R/R T-ALL/LBL; 29 of whom were treated with combination therapy, most with cyclophosphamide and etoposide (23, 79%) and 15 with monotherapy. The median age was 19 years (range, 2-69), including 18 children (<18 years). After a median of 1 (range, 1-3) cycle of treatment, 24 patients (55%) achieved complete remission, 62% (18/29) with combination therapy and 40% (6/15) with monotherapy (P = .21). Most responders (21, 88%) pursued allogeneic stem cell transplant (alloSCT). Overall survival (OS) was 12.8 months (95% confidence interval, 6.93-not reached) in the entire cohort and was higher in the combination therapy than in the monotherapy group (24-month OS, 53% vs 8%; P = .003). The rate of neurotoxicity was similar between groups (27% vs 17%; P = .46) and grade 3/4 anemia and thrombocytopenia were more frequent in the combination group (76% vs 20%; P < .001% and 66% vs 27%; P = .014, respectively). In a multivariate analysis, nelarabine combination therapy and alloSCT post nelarabine were associated with improved OS (hazard ratio, 0.41; P = .04 and hazard ratio, 0.25; P = .008, respectively). In conclusion, compared with monotherapy, nelarabine combination therapy was well tolerated and associated with improved survival in pediatric and adult patients with R/R T-ALL/LBL.

Ascertaining QUAZARs: slow-motion and light-speed development of oral azacitidine and decitabine.

Myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) are devastating diseases that frequently rely on the use of parenteral hypomethylating agents (HMAs), either as monotherapy or in combination, as first-line treatment for many patients. Two new oral HMAs, decitabine/cedazuridine (DC) for use in place of azacitidine or decitabine in MDS, and azacitidine (CC-486) for use as maintenance treatment in AML, were recently approved by the FDA. We will discuss the development of these oral HMAs, including the advantages/disadvantages in transitioning to oral HMAs and an in depth look at the pivotal phase III trials that led to their FDA approval - ASCERTAIN for DC and QUAZAR-AML-001 for CC-486. We also review how these agents have been and are being studied in other malignancies, and examine the future role that these exciting novel agents will play in both MDS and AML.

Oral Mercaptopurine Adherence in Pediatric Acute Lymphoblastic Leukemia: A Survey Study From the Dana-Farber Cancer Institute Acute Lymphoblastic Leukemia Consortium.

Background: Oral chemotherapy nonadherence is a challenge in clinical oncology. During therapy for acute lymphoblastic leukemia (ALL), poor adherence to 6-mercaptopurine (6MP) increases relapse risk. Clinically significant nonadherence is reported in 30% of children treated for ALL on Children's Oncology Group (COG) trials. Whether nonadherence rates vary across regimens with different treatment schedules and modes of administration is unknown. Methods: We conducted an exploratory, cross-sectional survey study on parents of children (1-18 years) receiving continuation therapy on, or as per Dana-Farber Cancer Institute (DFCI) ALL Consortium Protocol 11-001. Treatment required weekly visits to the clinic and 14 days of oral 6MP every 3 weeks. Survey assessed self-reported sociodemographics, medication-taking, chemotherapy comprehension, and 6MP adherence; adherence survey items were developed from published surveys. Patients were grouped as nonadherent if they endorsed missing one 6MP dose during the last cycle, or more than one dose during prior cycles, for nonmedical reasons. Results: Sixty-two families completed the surveys, all of whom had evaluable adherence data. In total, 25% of patients met the study definition of nonadherence. Twenty-three percent reported that it was "not easy" to follow administration guidelines around the dairy intake and 57% requested more teaching and educational resources. Conclusion: Self-reported nonadherence to oral 6MP in the DFCI ALL Consortium is high, with rates similar to those observed in the COG. This suggests that the additional contact during weekly infusions on the DFCI is insufficient to address barriers affecting oral chemotherapy adherence.

Outcomes of Childhood Noninfant Acute Lymphoblastic Leukemia With 11q23/KMT2A Rearrangements in a Modern Therapy Era: A Retrospective International Study.

PURPOSE: We aimed to study prognostic factors and efficacy of allogeneic hematopoietic stem-cell transplantation (allo-HSCT) in first remission of patients with noninfant childhood acute lymphoblastic leukemia (ALL) with 11q23/KMT2A rearrangements treated with chemotherapy regimens between 1995 and 2010. PATIENTS AND METHODS: Data were retrospectively retrieved from 629 patients with 11q23/KMT2A-rearranged ALL from 17 members of the Ponte-di-Legno Childhood ALL Working Group. Clinical and biologic characteristics, early response assessed by minimal residual disease at the end of induction (EOI) therapy, and allo-HSCT were analyzed for their impact on outcomes. RESULTS: A specific 11q23/KMT2A translocation partner gene was identified in 84.3% of patients, with the most frequent translocations being t(4;11)(q21;q23) (n = 273; 51.5%), t(11;19)(q23;p13.3) (n = 106; 20.0%), t(9;11)(p21_22;q23) (n = 76; 14.3%), t(6;11)(q27;q23) (n = 20; 3.8%), and t(10;11)(p12;q23) (n = 14; 2.6%); 41 patients (7.7%) had less frequently identified translocation partner genes. Patient characteristics and early response varied among subgroups, indicating large biologic heterogeneity and diversity in therapy sensitivity among 11q23/KMT2A-rearranged ALL. The EOI remission rate was 93.2%, and the 5-year event-free survival (EFS) for the entire cohort was 69.1% ± 1.9%, with a range from 41.7% ± 17.3% for patients with t(9;11)-positive T-ALL (n = 9) and 64.8% ± 3.0% for patients with t(4;11)-positive B-ALL (n = 266) to 91.2% ± 4.9% for patients with t(11;19)-positive T-ALL (n = 34). Low EOI minimal residual disease was associated with favorable EFS, and induction failure was particularly predictive of nonresponse to further therapy and relapse and poor EFS. In addition, EFS was not improved by allo-HSCT compared with chemotherapy only in patients with both t(4;11)-positive B-ALL (n = 64 v 51; P = .10) and 11q23/KMT2A-rearranged T-ALL (n = 16 v 10; P = .69). CONCLUSION: Compared with historical data, prognosis of patients with noninfant 11q23/KMT2A-rearranged ALL has improved, but allo-HSCT failed to affect outcome. Targeted therapies are needed to reduce relapse and treatment-related mortality rates.

Recombinant Erwinia asparaginase (JZP458) in acute lymphoblastic leukemia: results from the phase 2/3 AALL1931 study.

AALL1931, a phase 2/3 study conducted in collaboration with the Children's Oncology Group, investigated the efficacy and safety of JZP458 (asparaginase erwinia chrysanthemi [recombinant]-rywn), a recombinant Erwinia asparaginase derived from a novel expression platform, in patients with acute lymphoblastic leukemia/lymphoblastic lymphoma who developed hypersensitivity/silent inactivation to Escherichia coli-derived asparaginases. Each dose of a pegylated E coli-derived asparaginase remaining in patients' treatment plan was substituted by 6 doses of intramuscular (IM) JZP458 on Monday/Wednesday/Friday (MWF). Three regimens were evaluated: cohort 1a, 25 mg/m2 MWF; cohort 1b, 37.5 mg/m2 MWF; and cohort 1c, 25/25/50 mg/m2 MWF. Efficacy was evaluated by the proportion of patients maintaining adequate nadir serum asparaginase activity (NSAA ≥0.1 IU/mL) at 72 hours and at 48 hours during the first treatment course. A total of 167 patients were enrolled: cohort 1a (n = 33), cohort 1b (n = 83), and cohort 1c (n = 51). Mean serum asparaginase activity levels (IU/mL) at 72 hours were cohort 1a, 0.16, cohort 1b, 0.33, and cohort 1c, 0.47, and at 48 hours were 0.45, 0.88, and 0.66, respectively. The proportion of patients achieving NSAA ≥0.1 IU/mL at 72 and 48 hours in cohort 1c was 90% (44/49) and 96% (47/49), respectively. Simulated data from a population pharmacokinetic model matched the observed data well. Grade 3/4 treatment-related adverse events occurred in 86 of 167 (51%) patients; those leading to discontinuation included pancreatitis (6%), allergic reactions (5%), increased alanine aminotransferase (1%), and hyperammonemia (1%). Results demonstrate that IM JZP458 at 25/25/50 mg/m2 MWF is efficacious and has a safety profile consistent with other asparaginases. This trial was registered at www.clinicaltrials.gov as #NCT04145531.

Feasibility of oncology clinical trial-embedded evaluation of social determinants of health.

Social determinants of health (SDoH) are associated with stark disparities in cancer outcomes, but systematic SDoH data collection is virtually absent from oncology clinical trials. Trial-based SDoH data are essential to ensure representation of marginalized populations, contextualize outcome disparities, and identify health-equity intervention opportunities. We report the feasibility of a pediatric oncology multicenter therapeutic trial-embedded SDoH investigation. Among 448 trial participants, 392 (87.5%) opted-in to the embedded SDoH study; 375 (95.7%) completed baseline surveys, with high longitudinal response rates (88.9-93.1%) over 24 months. Trial-embedded SDoH data collection is feasible and acceptable and must be consistently included within future oncology trials.

Nelarabine, etoposide, and cyclophosphamide in relapsed pediatric T-acute lymphoblastic leukemia and T-lymphoblastic lymphoma (study T2008-002 NECTAR).

Children with relapse of T-cell acute lymphoblastic leukemia (T-ALL) or lymphoblastic lymphoma (T-LBL) have a dismal prognosis, largely due to difficulty attaining second remission. We hypothesized that adding etoposide and cyclophosphamide to the nucleoside analog nelarabine could improve response rates over single-agent nelarabine for relapsed T-ALL and T-LBL. This phase I dose-escalation trial's primary objective was to evaluate the dose and safety of nelarabine given in combination with etoposide at 100 mg/m2 /day and cyclophosphamide at 330-400 mg/m2 /day, each for 5 consecutive days in children with either T-ALL (13 patients) or T-LBL (10 patients). Twenty-three patients were treated at three dose levels; 21 were evaluable for dose-limiting toxicities (DLT) and response. The recommended phase II doses (RP2D) for this regimen, when given daily ×5 every 3 weeks, were nelarabine 650 mg/m2 /day, etoposide 100 mg/m2 /day, and cyclophosphamide 400 mg/m2 /day. DLTs included peripheral motor and sensory neuropathies. An expansion cohort to evaluate responses at the RP2D was terminated early due to slow accrual. The overall best response rate was 38% (8/21), with 33% (4/12) responses in the T-ALL cohort and 44% (4/9) responses in the T-LBL cohort. These response rates are comparable to those seen with single-agent nelarabine in this setting. These data suggest that the addition of cyclophosphamide and etoposide to nelarabine does not increase the incidence of neurologic toxicities or the response rate beyond that obtained with single-agent nelarabine in children with first relapse of T-ALL and T-LBL.

JAK3 mutations and mitochondrial apoptosis resistance in T-cell acute lymphoblastic leukemia.

Resistance to mitochondrial apoptosis predicts inferior treatment outcomes in patients with diverse tumor types, including T-cell acute lymphoblastic leukemia (T-ALL). However, the genetic basis for variability in this mitochondrial apoptotic phenotype is poorly understood, preventing its rational therapeutic targeting. Using BH3 profiling and exon sequencing analysis of childhood T-ALL clinical specimens, we found that mitochondrial apoptosis resistance was most strongly associated with activating mutations of JAK3. Mutant JAK3 directly repressed apoptosis in leukemia cells, because its inhibition with mechanistically distinct pharmacologic inhibitors resulted in reversal of mitochondrial apoptotic blockade. Inhibition of JAK3 led to loss of MEK, ERK and BCL2 phosphorylation, and BH3 profiling revealed that JAK3-mutant primary T-ALL patient samples were characterized by a dependence on BCL2. Treatment of JAK3-mutant T-ALL cells with the JAK3 inhibitor tofacitinib in combination with a spectrum of conventional chemotherapeutics revealed synergy with glucocorticoids, in vitro and in vivo. These findings thus provide key insights into the molecular genetics of mitochondrial apoptosis resistance in childhood T-ALL, and a compelling rationale for a clinical trial of JAK3 inhibitors in combination with glucocorticoids for patients with JAK3-mutant T-ALL.