Philadelphia-negative Acute Lymphoblastic Leukemia Research Articles

WGCNA-based identification of anoikis-related subtypes, prognostic significance, and characterisation of the immune microenvironment in Philadelphia-negative acute lymphoblastic leukaemia

WGCNA-based identification of anoikis-related subtypes, prognostic significance, and characterisation of the immune microenvironment in Philadelphia-negative acute lymphoblastic leukaemia

Refining risk stratification in paediatric B-acute lymphoblastic leukaemia: Combining IKZF1plus and Day 15 MRD positivity.

This study investigates the potential utility of IKZF1 deletion as an additional high-risk marker for paediatric acute lymphoblastic leukaemia (ALL). The prognostic impact of IKZF1 status, in conjunction with minimal/measurable residual disease (MRD), was evaluated within the MRD-guided TPOG-ALL-2013 protocol using 412 newly diagnosed B-ALL patients aged 1-18. IKZF1 status was determined using multiplex ligation-dependent probe amplification. IKZF1 deletions, when co-occurring with CDKN2A, CDKN2B, PAX5 or PAR1 region deletions in the absence of ERG deletions, were termed IKZF1plus. Both IKZF1 deletion (14.6%) and IKZF1plus (7.8%) independently predicted poorer outcomes in B-ALL. IKZF1plus was observed in 4.1% of Philadelphia-negative ALL, with a significantly lower 5-year event-free survival (53.9%) compared to IKZF1 deletion alone (83.8%) and wild-type IKZF1 (91.3%) (p < 0.0001). Among patients with Day 15 MRD ≥0.01%, provisional high-risk patients with IKZF1plus exhibited the worst outcomes in event-free survival (42.0%), relapse-free survival (48.0%) and overall survival (72.7%) compared to other groups (p < 0.0001). Integration of IKZF1plus and positive Day 15 MRD identified a subgroup of Philadelphia-negative B-ALL with a 50% risk of relapse. This study highlights the importance of assessing IKZF1plus alongside Day 15 MRD positivity to identify patients at increased risk of adverse outcomes, potentially minimizing overtreatment.

A Comparative Study of Hyper-CVAD and Modified CALGB-10403 Regimens in Adults with Philadelphia-Negative Acute Lymphoblastic Leukemia

Introduction: Induction with pediatric-inspired regimens (PIR) in young adults with acute lymphoblastic leukemia (ALL) is being increasingly used due to its demonstrated improvement in overall survival (OS) compared to historical adult regimens. However, in certain comparisons, PIR, specifically augmented BFM, did not exhibit an OS benefit when compared to the adult Hyper-CVAD regimen. Additionally, Hispanic patients with ALL often present with disease-related high-risk features and a high prevalence of comorbidities like obesity and metabolic syndrome, which may contribute to unfavorable outcomes and a particular adverse event profile. This study aimed to compare the OS and relapse-free survival (RFS) of patients treated with a PIR, a modified CALGB 10403 (mCALGB), and the Hyper-CVAD regimen. Methods: This observational retrospective cohort study was conducted at a single reference center in Mexico City. The study included adult patients aged 18-49 years with newly diagnosed Philadelphia (Ph)-negative ALL who received induction chemotherapy with either mCALGB or Hyper-CVAD between January 2015 and May 2023. High-risk karyotype was defined by hypodiploid, complex, or t(v;11q23), and hyperleukocytosis was characterized by &amp;gt; 30 x 10 3/µL white blood cells. Measurable residual disease (MRD) was assessed via flow cytometry. A comparative analysis of sociodemographic, clinical, and laboratory characteristics was performed between the two treatment groups using Student's t-test (parametric) or U Mann-Whitney (non-parametric) for continuous variables, and the Chi-square / exact Fisher tests for categorical variables. OS and RFS were estimated using Kaplan-Meier survival analysis, and the log-rank test was used to compare both survivals. A Cox regression analysis was performed to identify prognostic factors for OS and RFS. Results: The study included 100 patients: 36 treated with Hyper-CVAD and 64 with mCALGB. The median age at diagnosis was 26 years (IQR 20.5-38), with 56% being male, and 52% being overweight or obese. No statistically significant differences were observed in the clinical and laboratory features between the treatment groups (see Table 1). Regarding induction-related mortality, febrile neutropenia, or admission to an intensive care unit during induction, no differences were found between Hyper-CVAD and mCALGB (see Table 1). A non-significant trend towards a higher rate of grade 3 or 4 hepatotoxicity during induction was observed in patients receiving the modified CALGB 10403: 56.3% vs. 36.1% with an odds ratio (OR) of 2.275 (95% CI 0.982-5.272), p=0.063. The complete response (CR) rate was 87.6%. MRD was assessed in 83% of patients, with &amp;lt;0.1% detected in 62.7% of them. There were no differences between Hyper-CVAD and mCALGB regarding CR or MRD&amp;lt;0.1% (88.9% vs. 86.9%, p=1, and 53.8% vs. 66.7%, p=0.330, respectively). The relapse rate for the entire population was 41.8%, with Hyper-CVAD demonstrating a higher relapse rate compared to mCALGB: 64.7% vs. 28.1%, p=0.001. The median RFS was 54.1 months (95% CI NR-NR) for mCALGB and 12.7 months (95% CI 2.9-22.5) for Hyper-CVAD, with a 3-year RFS of 61.2% vs. 31.5%, p=0.008. In a multivariate analysis for RFS, significant prognostic factors included WBC &amp;gt;30 x 10 3/µL (HR 4.47, 95% CI 2.09-9.57, p&amp;lt;0.001), post-induction MRD &amp;gt;0.1% (HR 4.07, 95% CI 1.86-8.90, p&amp;lt;0.001), and mCALGB vs. Hyper-CVAD (HR 0.37, 95% CI 0.18-0.78, p=0.01). The median OS for the entire cohort was 32.3 months (95% CI 28.3-80.1), with mCALGB demonstrating a non-reached (NR) median OS (95% CI NR-NR), and Hyper-CVAD exhibiting a median OS of 22.4 months (95% CI 13.8-31) with a 3-year OS of 64.8% vs. 35.0%, p=0.037 (see Figure 1). In a multivariate analysis for OS, significant prognostic factors included WBC &amp;gt;30 x 10 3/µL (HR 3.57, 95% CI 1.58-8.09, p=0.002), post-induction MRD &amp;gt;0.1% (HR 2.58, 95% CI 1.17-5.69, p=0.002), and mCALGB vs. Hyper-CVAD (HR 0.29, 95% CI 0.13-0.66, p=0.003). Conclusion: Among a cohort of Mexican patients, treatment with mCALGB was independently associated with better RFS and OS compared to Hyper-CVAD.

Survival Outcomes, Efficacy and Tolerability of a Pediatric-Inspired Regimen (MASPORE) for Philadelphia-Negative Acute Lymphoblastic Leukemia in Young Adults at a Tertiary Hospital in Singapore

Introduction: Recent evidence has emerged to support the use of pediatric-inspired regimen as a standard of care in Adolescents and Young Adults (AYA) patients diagnosed with Philadelphia-negative acute lymphoblastic leukemia (Ph- ALL). The backbone of the pediatric regimen is high cumulative doses of steroids, asparaginase, vincristine and more intensive CNS prophylaxis. Most literature, however, has been in the western population, with few data reported in Asia. MASPORE protocol is a locally designed pediatric-inspired regimen for treatment of ALL in AYA. The protocol uses a 3- or 4-drugs induction regimen (L-asparaginase, Vincristine, Dexamethasone +/- Daunorubicin) based on standard or high-risk disease. PCR-based measurable residual disease (MRD) marker was utilized for disease monitoring and dynamic risk stratification, which led to subsequent intensification of regimen as needed. Methods: In this IRB approved retrospective analysis, patients aged 18-39 years old with Ph- ALL who received MASPORE regimen from January 2009 to December 2021 at the National University Hospital Singapore were identified via our institution database. Treatment outcomes, including measurable residual disease (MRD) monitoring, and toxicity profile were analyzed. Survival outcomes were estimated using Kaplan-Meier method. High risk disease at diagnosis was defined as high white blood cell (&amp;gt;30x10 9/L for B-ALL, &amp;gt;100x10 9/L for T-ALL), hypodiploidy, t(4;11) and other MLL gene rearrangement. Results: 32 patients were identified during the study period; 3 patients were excluded due to incomplete data. The median age was 23 years old (range 18-33 years) with majority being male (86.2%). 16 patients (55.2%) had B-ALL and 13 (44.8%) had T-ALL. High risk disease was present in 7 (43.8%) B-ALL patients and 8 (61.5%) in T-ALL patients. 2 patients in B-ALL group had CNS involvement at diagnosis. The majority (96.5%) achieved complete remission after the induction phase. 1 patient died within first 1 month of treatment due to pancreatitis. 5 patients in high risk group received allogenic stem cell transplantation (alloSCT), whereas 2 patients with standard risk required alloSCT due to relapse and persistent MRD positivity. MRD result was available for 26 patients. In the entire cohort, MRD negativity was achieved in 22 patients (75.9%). Subtype was not associated with achievement of MRD negativity (80% in B-ALL vs 90.9% in T-ALL). High risk patients however had a lower odds of achieving MRD negativity after induction (OR 0.114 95% CI 0.017-0.742, p=0.021). The median follow-up for survivors was 41 months (range 27 to 89 months). Relapse and mortality rate was low at 13.8% each. 5-year OS for patients with B-ALL and T-ALL were 92.3% and 75.2%, respectively (Figure 1a). 5-year OS for patients with standard and high-risk disease were 84.4% and 84.0%, respectively (Figure 1b). Delayed achievement of MRD negativity (i.e. after induction) was not associated with inferior survival outcomes, albeit our sample size was small. In terms of adverse events, Asparaginase-related toxicities included 11 patients (37.9%) with thrombotic events (4 cerebral venous thrombosis and 7 deep vein thrombosis), and 5 patients (17.2%) with grade 2 or more pancreatitis. 7 patients (24.1%) had at least 1 episode of grade 3 or 4 transaminitis. 7 patients (24.1%) had grade 3 or 4 sepsis during the course of treatment. 2 patients developed osteonecrosis of the hip requiring operation and cessation of steroids. Conclusion: Our locally designed MASPORE protocol tailored in accordance to risk stratification demonstrated promising survival outcomes. Similar outcomes observed in standard and high-risk disease suggests the benefit of such an approach. Toxicities were mainly related to L-asparaginase use. Individualized dosing based on drug level monitoring will help to further optimize the treatment intensity with reduced toxicities.

High Efficacy and Feasibility of a Full Pediatric Induction in Adults Aged up to 55 Years with Philadelphia-Negative Acute Lymphoblastic Leukemia

Background: Treatment of acute lymphoblastic leukemia (ALL) in adults has historically shown unsatisfactory outcomes when compared to the outstanding results obtained in pediatric patients. Pediatric protocols rely on increased drug intensity and on a tighter evaluation of minimal residual disease (MRD) for early intensification. Nowadays, pediatric-inspired protocols have been established as the standard of care for adolescents and young adult patients (AYA) leading to improved results. In the setting of older patients, probably due to the limited data available, the feasibility of such intensive therapies, and in particular the administration of high doses PEG-asparaginase (PEGASP), is still a matter of debate. In this context, the NOPHO group reported that a full-pediatric protocol was feasible and highly effective in adult patients, up to 45 years of age. Aim: The aim of our study was to evaluate the feasibility and efficacy of the entire full pediatric AIEOP-BFM LAL 2009 protocol in an older cohort of adult patients up to 55 years. Methods: Since May 2013, 28 consecutive adults diagnosed with Ph-neg ALL received first line therapy according to AIEOP- BFM-ALL 2009 protocol, which includes high PEG-asparaginase (PEGASP) doses, with an accurate MRD-driven therapeutic strategy. The protocol consists of 2 induction blocks: IA (Vincristine, Daunorubicin, PEGASP, IT methotrexate) and IB (Cytarabine, 6-mercaptopurine, cyclophosphamide, IT methotrexate), I consolidation block (high-dose methotrexate, 6-mercaptopurine, IT methotrexate), maintenance therapy (6-mercaptopurine, weekly MTX, IT Methotrexate). Median age in our study was 45 years (range 17-55), equal to the maximum age allowed in the NOPHO study. Fifteen patients had B-ALL, 13 T-ALL/T including 5 Early-T phenotype. Dose intensification and stem cell transplantation (SCT) were scheduled according to baseline and MRD-driven risk assessment. MRD was evaluated by multicolor-flow cytometry (MFC), with a threshold for positivity of 0.025%, and molecular PCR for JH rearrangement (MOL), with a sensitivity greater or equal to 10-4 in all patients. Patients with MOL MRD &amp;gt;10-4 but &amp;lt;10-3 were defined as low-level positive. MRD time points were day 33 and day 78 (MFC and MOL). Results: All patients achieved complete hematological remission following the first Induction course (100%). One patient died during induction due to infection by multidrug resistant P. aeruginosa. In general, therapy was well tolerated. Remarkably, patients in this study received high dose of PEGASP (median 10000 UI/sqm, equal to 4 administrations at 2500 UI/sqm each) without experimenting life threatening toxicities, which mostly consisted in asymptomatic elevation of transaminase (7 patients G3, 1 G4) and/or bilirubin (9 patients G3, 1 G4) only requiring supportive therapy. No major bleeding or thrombotic events o other &amp;gt;G2 toxicities were observed. All except one patient achieved CR at day 33 and all patients achieved CR at day 78. MFC MRD evaluation at day 33 resulted negative in 24/25 evaluable patients (95%). Day 33 MOL-MRD was evaluated in 22 patients, and resulted negative, low level positive or positive in 14, 5 and 3 patients, respectively. MRD assessment at day 78 showed both MFC and MOL negativity achieved in all 25 and 22 evaluated patients, respectively (Fig. 1). Four very high-risk patients underwent SCT in negative MRD status. After a median follow-up of 59 months (CI 95% 38.45-78.63), median survival was not reached, 5-years OS was 88.7% (Fig. 2). One patient died due to progressive transverse myelitis after isolated CNS relapse and one patient died due to sudden cardiac arrest while in complete MRD negative remission, 6 months after completion of therapy. All other 25 patients are alive and in complete MRD negative remission. Conclusion: The application of a full pediatric induction regimen in a cohort of adult ALL patients with a median age of 45 years proved to be feasible, with tolerable toxicities. In particular, we didn't observe major toxicities during the intensified PEGASP administration and all patients were able to receive the planned PEGASP doses. The possibility to maintain the correct timing translated in a very high MRD negativity rate and promising OS survival.

Comparable Outcomes of Relapsed Acute Lymphoblastic Leukemia in Adolescents and Young Adults (AYA) Patients Treated with Pediatric-Inspired Chemotherapy (R3 protocol) Versus Adult-Based Salvage (FA) Protocol

Background Although the survival rate of adolescents and young adults (AYA) with acute lymphoblastic leukemia (ALL) has improved by using pediatric-based treatment protocols, those who experience a relapse still have poor outcomes when treated with adult chemotherapy salvage-regimens, which have traditionally included high doses of Ara-C. The long-term survival rate for patients treated with these salvage-regimens is less than 10%. Salvage treatment with blinatumomab for adults with relapsed B-cell ALL results in a complete remission (CR) rate of 34%, a median survival of 7.7 months, and an overall survival (OS) of less than 30% at 18 months. In contrast, the ALLR3 protocol for relapsed ALL in patients up to the age of 18 years achieved a CR rate of 97% and an overall survival rate of 72%. Therefore, this study aims to compare the outcomes of AYA patients treated with pediatric-inspired regimen (R3 regimen) to those treated with adult-based regimen (FA (Fludarabine/Cytarabine) protocol). Methods The R3 protocol treated 17 AYA patients with relapsed Philadelphia-negative ALL, aged between 14 to 40 years old, who had received first-line therapy. Patients who achieved CR underwent allogenic transplant. The protocol included vincristine, mitoxantrone, asparaginase, dexamethasone, and intrathecal methotrexate. In comparison, 60 patients were treated with FA protocol, with patients achieved CR proceeded to allogeneic stem cell transplantation. Relapses were classified as very early (&amp;lt; 18 months from diagnosis), early (&amp;gt;18 months from diagnosis and &amp;lt;6 months from the end of therapy), and late (&amp;gt;6 months from the end of therapy). Patients' characteristics, response rate (RR) and overall survival (OS) were analyzed. Results The two arms had comparable characteristics. The median age in the R3 arm was 16 years (range: 14-40 years) compared to 22 years (range: 18-32 years) in the FA protocol arm. In the R3 arm, 88.2% of patients had B-cell ALL, while in the FA protocol arm, 92.2% had B-cell ALL. CNS involvement was seen in 28.8% and 17.6% of cases in the R3 and FA protocol arms, respectively. Relapses were classified as very early, early, or late in 2 (12%), 5 (29%), and 7 (41%) of cases in the R3 arm and were mostly late (25.2%) in the FA protocol arm. Relapses in the R3 arm were isolated bone marrow (BM), isolated extramedullary (EMD), or combined BM and EMD in 14 (82%), 1 (6%), and 2 (12%) cases, respectively, while EMD was around three times higher (16.9%) in the FA arm. The overall CR rate was 60% at the end of R3 induction, with negative MRD (&amp;lt;10 −4 cells) in 47.1% of patients. The overall CR rate was higher in the FA arm (76.3%), but the difference with the R3 arm was not statistically significant (p-value 0.1). The disease was refractory to subsequent salvage therapy in 42% of cases in both arms. About half of the patients who responded to R3 proceeded to allogeneic stem cell transplant (52.3%), while 78% of the patients post-FA underwent transplantation. Eight patients died (47%) in R3 arm, but only one patient died due to treatment-related sepsis, while the other seven patients died due to disease-related causes. At a median follow-up of 4 years, OS was 53% in the R3 arm compared to 30.8% in the FA arm, but the difference was not significant (p-value=0.8). The post-FA mortality was mainly due to infections (15.3% in FA vs. 5.9% in R3). Conclusion Pediatric-inspired protocols that have shown significant benefits in the front-line setting for ALL in the AYA population did not demonstrate a significant difference when compared to traditional adult-based salvage chemotherapy regimens in relapsed disease.

Allogeneic Hematopoietic Stem Cell Transplantation in Adolescents and Young Adults with Acute Lymphoblastic Leukemia - Retrospective Dual-Center Study

Background: Adolescents and young adults (AYAs) with acute lymphoblastic leukemia (ALL) are treated with various chemotherapy regimens. Some patients undergo allogeneic hematopoietic stem cell transplantation (HCT) due to high-risk genetic characteristics, chemo-resistant disease (failure to achieve timely measurable residual disease (MRD) negative remissions, or relapse or refractory disease. There is paucity of data on outcomes of AYA ALL patients receiving HCT. Methods: We performed a dual-center analysis of data from MD Anderson Cancer Center (MDACC) and Dana-Farber Cancer Institute (DFCI) to evaluate outcomes of AYA patients who received HCT for Philadelphia-negative (Ph neg) ALL and examined variables that might have an impact on these outcomes. We included all patients who received their first HCT between the ages of 15-40 years between the years 2010-2022. MRD status was evaluated using flow cytometry with a sensitivity of 0.01%. Acute and chronic graft versus host disease (GvHD) were classified according to consensus criteria. The primary endpoint was overall survival (OS), and secondary endpoints included progression rate and non-relapse mortality (NRM). Cox proportional hazards regression analysis was used to evaluate predictors of OS, and Fine and Gray regression for predictors of relapse and NRM. Competing risks were accounted for in analyses pertaining to progression and NRM. Results: A total of 376 Ph neg ALL AYA patients were included in the analysis, 247 from MDACC and 129 from DFCI. The median age at transplant was 25 (range 15-40) years, 39 patients (10%) were aged ≤18 years at time of HCT and 251 (67%) were males.The majority had B-ALL (n=282, 75%), 42 (11%) had complex karyotype and 28 patients (7%) had translocation (4:11). Most patients received either pediatric-inspired (48%) or hyper- cyclophosphamide, vincristine sulfate, doxorubicin, dexamethasone (CVAD) based (42%) frontline induction regimens, and the median time from diagnosis to HCT was 11 (range 2-283) months. At transplant, most patients were in CR1 or CR2 (44% each); 63% of patients achieved MRD negativity prior to HCT. Most patients received an HCT from a matched unrelated donor (MUD) (33%) or a matched sibling donor (MSD) (32%), and most patients received myeloablative conditioning (MAC) (79%) ( Table 1). The cumulative incidence of grade 2-4 acute GvHD and grade 3-4 acute GvHD at 6 months was 37% (95% CI 33%-42%) and 13% (95% CI 10%-17%), respectively. The cumulative incidence of chronic GvHD at 3 years was 28% (95% CI 23%-33%), with most patients experiencing either mild (39%) or moderate (36%) chronic GvHD, and 25% had severe chronic GvHD. For patients transplanted in CR1, CR2 and CR3/PD the estimated 3-year OS was 69% (95% CI 61%-77%), 53% (95% CI 44%-61%) and 29% (95% CI 16%-43%), respectively; the 3-year NRM rate was 9% (95% CI 5%-15%), 18% (95% CI 13%-25%) and 27% (95% CI 16%-43%), respectively; and the 3-year progression rate was 27% (95% CI 20%-35%), 36% (95% CI 29%-45%) and 48% (95% CI 36%-65%), respectively. In multivariate analysis, HCT in CR3/PD was associated with inferior OS (HR 4.3, p&amp;lt;0.001) and higher NRM (HR 2.3, p=0.04, Table 2), however there was no difference in survival between HCT at CR1 vs. CR2 (p=0.3); &amp;gt;2 lines of therapy prior to HCT was associated with inferior OS (HR 1.8, p=0.004) and higher rate of progression (HR 1.9, p=0.008); HCT-CI&amp;gt;3 was associated with inferior OS (HR 1.6, p=0.01) and higher NRM (2.3, p=0.004); positive MRD status prior to HCT was associated with inferior OS (HR 1.9, p=0.004) and higher rate of progression (HR 3.3, p&amp;lt;0.001); use of bone marrow graft was associated with lower rate of progression (HR 0.6, p=0.02) and use of a matched donor (MSD/MUD) was associated with lower NRM (HR 0.5, p=0.01). Conclusions: In this analysis of a large dual-center cohort of AYA Ph -ALL patients that received HCT, we found that patients transplanted in CR1 had the most favorable outcomes with 69% 3-year OS. Patients not in CR1/CR2, patients who received HCT after &amp;gt;2 lines of therapy and those with positive MRD pre-HCT had inferior OS on MVA. Although patients who received HCT at CR3/PD had inferior OS, an estimated one-third of patients were still alive at 3 years after HCT.

POSTER: ALL-363 Comparison of Treatment Outcomes in Adolescents and Young Adults (AYA) With Philadelphia Negative Acute Lymphoblastic Leukemia (ALL) Treated With HyperCVAD and Pediatric-Inspired Protocols (PIPs)

POSTER: ALL-363 Comparison of Treatment Outcomes in Adolescents and Young Adults (AYA) With Philadelphia Negative Acute Lymphoblastic Leukemia (ALL) Treated With HyperCVAD and Pediatric-Inspired Protocols (PIPs)

Oral Abstract: ALL-363 Comparison of Treatment Outcomes in Adolescents and Young Adults (AYA) With Philadelphia Negative Acute Lymphoblastic Leukemia (ALL) Treated With HyperCVAD and Pediatric-Inspired Protocols (PIPs)

Oral Abstract: ALL-363 Comparison of Treatment Outcomes in Adolescents and Young Adults (AYA) With Philadelphia Negative Acute Lymphoblastic Leukemia (ALL) Treated With HyperCVAD and Pediatric-Inspired Protocols (PIPs)

ALL-363 Comparison of Treatment Outcomes in Adolescents and Young Adults (AYA) With Philadelphia Negative Acute Lymphoblastic Leukemia (ALL) Treated With HyperCVAD and Pediatric-Inspired Protocols (PIPs)

ALL-363 Comparison of Treatment Outcomes in Adolescents and Young Adults (AYA) With Philadelphia Negative Acute Lymphoblastic Leukemia (ALL) Treated With HyperCVAD and Pediatric-Inspired Protocols (PIPs)

Venetoclax durable response in adult relapsed/refractory Philadelphia-negative acute lymphoblastic leukemia with JAK/STAT pathway alterations.

High-risk relapsed/refractory adult Philadelphia-negative (Ph-) B-cell acute lymphoblastic leukemia (B-ALL) is a great challenge due to limited possibilities to achieve and maintain a complete response. This also applies to cases with extramedullary (EM) involvement that have poor outcomes and no accepted standard therapeutic approaches. The incidence of EM localization in relapsed/refractory B-ALL is poorly investigated: data on patients treated with blinatumomab reported a 40% rate. Some responses were reported in EM patients with relapsed/refractory B-ALL treated with inotuzumab ozogamicin or CAR-T. However, molecular mechanisms of response or refractoriness are usually investigated neither at the medullary nor at EM sites. In the complex scenario of pluri-relapsed/refractory B-ALL patients, new target therapies are needed. Our analysis started with the case of an adult pluri-relapsed Ph- B-ALL patient, poorly sensitive to inotuzumab ozogamicin, donor lymphocyte infusions, and blinatumomab in EM disease, who achieved a durable/complete response after treatment with the BCL2-inhibitor venetoclax. The molecular characterization of medullary and EM samples revealed a tyrosine kinase domain JAK1 mutation in the bone marrow and EM samples at relapse. By comparing the expression level of BCL2- and JAK/STAT pathway-related genes between the patient samples, 136 adult JAK1 wt B-ALL, and 15 healthy controls, we identified differentially expressed genes, including LIFR, MTOR, SOCS1/2, and BCL2/BCL2L1, that are variably modulated at diverse time points and might explain the prolonged response to venetoclax (particularly in the EM site, which was only partially affected by previous therapies). Our results suggest that the deep molecular characterization of both medullary and EM samples is fundamental to identifying effective and personalized targeted therapies.

Comparison of a modified pediatric protocol versus a hyper-CVAD protocol in adolescents and young adults with Philadelphia-negative acute lymphoblastic leukemia: A multicenter retrospective analysis

BackgroundThe outcomes of Pediatric acute lymphoblastic leukemia (ALL) have improved dramatically whereas outcomes for ALL amongst adolescents and young adults (AYA) have lagged behind. The introduction of pediatric-like regimens to manage adult ALL has shown promising outcomes across several analyses. Materials and methodsIn this analysis, we aimed to retrospectively compare the differences in outcomes among patients aged 14–40 years with Philadelphia-negative ALL treated with a Hyper-CVAD protocol versus a modified pediatric protocol. ResultsA total of 103 patients were identified with 58 (56.3%) in the modified ABFM group and 45 (43.7%) in the hyper-CVAD group. The median duration of follow-up for the cohort was 39 months (range 1–93). There were significantly lower rates of MRD persistence after consolidation (10.3% vs. 26.7%, P = 0.031) and transplantation (15.5% vs. 46.6%, P < 0.001) in the modified ABFM group. 5-year OS rates (83.9% vs. 65.3%, P = 0.036) and DFS rates (67.4% vs. 44%, P = 0.014) were higher in the modified ABFM groups. The incidence of grade 3 and 4 hepatotoxicity (24.1% vs. 13.3%, P < 0.001) and osteonecrosis (20.6% vs. 2.2%, P = 0.005) were higher in the modified ABFM group. ConclusionOur analysis demonstrates that the use of a pediatric modified ABFM protocol demonstrated superior outcomes compared to the hyper-CVAD regimen in the treatment of Philadelphia-negative ALL amongst AYA patients. However, the modified ABFM protocol was associated with an increased risk of certain toxicities including high grade liver toxicity and osteonecrosis.

Role of measurable residual disease quantified by 4 to 6 color flow cytometry before allogeneic hematopoietic stem cell transplantation for high-risk Philadelphia-negative acute lymphoblastic leukemia

Background: Measurable residual disease (MRD) status before allogeneic hematopoietic stem cell transplantation (AHSCT) is commonly associated with a high risk of relapse. It is still uncertain whether AHSCT could overcome the negative impact of MRD positivity (MRD+), especially in patients with high-risk Philadelphia negative acute lymphoblastic leukemia (Ph-negative ALL). Materials and methods: An observational retrospective study was conducted on patients with high-risk Ph-negative ALL who underwent AHSCT between January 2005 and June 2022. The patients selected were in complete remission (CR): with 80% in CR1 (n = 69) and 20% in CR2 (n = 17). Graft sources were bone marrow (BM) in 71% of patients and peripheral blood stem cells in 29% of patients. The conditioning regimen was TBI or chemotherapy-based (CT). Bone marrow MRD level was quantified using 4-6 color multiparametric flow cytometry (MFC). The threshold for MRD positivity was ≥ 0.1%. Results: The study included 86 patients (45 B-ALL and 41 T-ALL) with a median age of 18 years (range, 4–55 years). The median level of MRD pre-AHSCT (pre-MRD) was 0.4×10-3 (range, 0.01-75.6×10-3). After a median follow-up of 25 months (range 1-205 months), the cumulative incidence of relapse (CIR) was significantly higher in the MRD+ group (39% vs. 20%, p = 0.04). The median time of relapse post-AHSCT was 14 months (range, 1-203 months) in the MRD+ group and 32 months (range, 4-209 months) in the MRD- group (p = 0.28). Non-relapse mortality (NRM) was 15% in both groups (p = 0.97). The 2-year estimated overall survival (OS) and event-free survival (EFS) were 61% vs. 74% (p = 0.07) and 58% vs. 70% (p = 0.10) in the MRD+ and MRD- groups, respectively. A subgroup analysis in MRD+ patients showed that a TBI-based conditioning regimen was distinctly associated with lower CIR (22% vs. 60% respectively, p = 0.04), improved OS (82% vs. 36% respectively, p = 0.007) and better EFS (73% vs. 38%, p = 0.04) compared to CT-based. In a multivariate analysis, pre-AHSCT MRD+ status and non-TBI-based conditioning were significantly associated with inferior OS (OR, 2.30; 95% CI, [1.027-5.168], p = 0.04 and OR, 3.91; 95% CI, [1.624-9.418], p = 0.002, respectively). The only predicting factor of lower EFS was the non-TBI-based regimen (OR, 2.82; 95% CI, [1.308-6.097], p = 0.008). Non-TBI-based and CR2 were significantly associated with higher CIR (OR, 6.25; 95% CI, [1.947-20.055], p = 0.002 and OR, 4.74; 95% CI, [1.197-18.791], p = 0.03, respectively). Peripheral stem cell source was significantly associated with higher NRM (OR, 6.55; 95% CI, [1.488-28.820], p = 0.01). Conclusion: High-risk Ph-negative ALL patients with MRD ≥ 10-3 prior AHSCT had lower OS compared to MRD- patients and may benefit from TBI as a conditioning regimen before AHSCT.

PH negative acute lymphoblastic leukemia in adolescents and young adults treated according a MRD adapted BFM ALL IC 2009 protocol: Argentine real-world data on 171 patients.

Intensified pediatric chemotherapy regimens to treat adolescents and young adults (AYA) patients with Philadelphia negative acute lymphoblastic leukemia (ALL) have been associated with better outcomes. The local BFM 2009-based scheme complements the risk stratification assessing the measurable residual disease (MRD) along the induction phase with increasing levels of sensitivity. The present retrospective multicenter analysis included 171 AYA (15-40 years) patients treated accordingly between 2013 and 2019. Ninety-one percent obtained morphological complete remission, 67% a negative (<0.1%) MRD at day 33 (TP1), and 78% a negative (<0.01%) MRD at day 78 (TP2). The overall survival (OS) and the event-free survival (EFS) at 2 years were 62%±4.1 and 55%±4.1, respectively. The OS and EFS were significant better for prednisone responders, who achieved <10% BM blast at day 15, a negative MRD at TP1 or at TP2, and for low-risk patients. Age ≤30 years and WBC <30×109/L, particularly among B-phenotype, were also associated with longer OS. In the multivariable analyses, TP1 MRD positive (OS HR 2.8, 95% CI 1.4-5.7, p=0.004; EFS HR 3.0, 95% CI 1.6-5.7, p=0.001) and at TP2 (OS HR 2.6, 95% CI 1.3-5.3, p=0.012; EFS HR 2.6, 95% CI 1.3-5.1, p=0.006) were independently associated with earlier events. Age >30 years was also associated with a shorter survival (HR 3.1, 95% CI 1.3-7.5, p=0.014). Therefore, those 68 patients ≤30 years with TP1/TP2 negative MRD depicted a longer OS (2 years 85%±4.8). Based on our real-world data, the pediatric-based scheme is feasible in Argentina associated with better outcomes for younger AYA patients who achieved negative MRD at day 33 and 78.

Outcomes in Hispanic Patients with Philadelphia-Negative and Philadelphia-like Acute Lymphoblastic Leukemia with the Use of Blinatumomab

Introduction: In the United States, Hispanics have the highest incidence rate of B-cell acute lymphoblastic leukemia (ALL) amongst all minority groups. Hispanic adults with ALL have the lowest rates of progression-free survival and overall survival. Hispanic adults, for example, have an increased frequency of Philadelphia chromosome (Ph)-like ALL, a sub-type of ALL associated with significantly inferior survival outcomes In the last decade, use of Blinatumomab and other novel targeted immunotherapies were approved for treatment of relapsed or minimal residual disease positive disease (MRD +) B-cell ALL. Pivotal trial showing efficacy of blinatumomab in relapsed or MRD + setting had very limited number of Hispanic patients. Our aim is to evaluate survival outcomes and the efficacy of blinatumomab usage in Hispanic B-ALL including Philadelphia-negative (Ph negative) and Philadelphia-like (Ph-Like) patients treated at LAC-USC (Los Angeles County Hospital-University of Southern California). We report Hispanic B-cell ALL patients treated with blinatumomab outside of clinical trials Method: This is a retrospective review which included adults aged ≥18 years with newly diagnosed Philadelphia negative ALL (2016-2020) treated at the USC/Norris Comprehensive Cancer Centerand the Los Angeles County Hospital (LAC). Primary objectives was to investigate overall survival in Hispanic patients who were treated with blinatumomab. We stratified patient population into Philadelphia negative and Philadelphia-like B-cell ALL and assessed survival separately for blinatumomab administered for minimal residual positivity and for relapse disease. Most of Ph-Like patients were identified with CRLF2 rearrangement per institutional protocol. Results: 67 patients were B cell ALL, which included Ph-negative B cell ALL and Ph-like B cell ALL, 43 and 24 patients respectively. 50.7% were men and median age was 39 years. 38 patients were considered unfavorable risk due to cytogenetics risk factors and 44 patients received peg-asparaginase based induction. 30 (48%) of patients received blinatumomab, 15 in each ph-negative and ph-like group respectively. More patients received blinatumomab for relapsed disease as compared to MRD positive disease, 23 vs. 8 patients respectively. Mean overall survival for our patients was 68 months (SE=3.3). In ph-negative group, when blinatumomab was used for relapsed disease then 3 years survival probability was 0% compared to 91.5% for patients who did not receive blinatumomab (p-value=0.0001). On the other hand, for MRD positive disease, 3 years OS was 91.7% vs. 79.6% for patients who received blinatumomab compared to no blinatumomab (p-value=0.6). For ph-like group, when blinatumomab was used for relapsed disease then 3 years survival probability was 100% compared to 40% for patients who did not receive blinatumomab (p-value=0.2). For MRD positive disease, median OS was not reached for either group (p-value=0.6). Conclusion: Both relapse disease and MRD+ disease are considered poor prognostic indicator. Our study highlights that blinatumomab can decrease survival gap for MRD + disease and relapse disease for ph-like Hispanic patients and decrease survival gap in MRD + ph-negative Hispanic patients when compared to patients who did not need blinatumomab

Updated Outcomes of the University of Southern California (USC) ALL Frontline Regimen (based on CCG-1882) after Protocol Modification in the Era of Novel Agents in Ph-Negative ALL Patients

INTRODUCTION: Pediatric inspired regimens in adolescent young adults and adults have improved outcomes in acute lymphoblastic leukemia (ALL). CALGB 10403 was prospectively tested in patients 17-39 years and achieved a 3-year event free survival of 59%. In 2007, we reported outcomes after incorporating peg-asparaginase (PEG) dosed at 2000mg/m in induction for patients aged 17- 55 years. This was well tolerated and achieved a complete remission (CR) rate of 96%. In 2014, we reported experience with the use of multiple doses of PEG (CCG-1882) for newly diagnosed ALL adult patients achieving a 7-year overall survival (OS) of 51%. Since then, the USC ALL regimen consisting of 2 induction phases, was further modified with a goal of maintaining good outcomes and improving compliance and toxicities. Fractionated doses of cytarabine were changed to a single dose, the methotrexate dose of 1g/ m2 (2.5 g/m2 if T cell) given D1,15 in intensification phases was changed to 3g/ m2 (B and T cell) given in single doses, and consolidation was increased to six cycles allowing for PEG holidays. Moreover, the approval and incorporation of novel agents such as blinatumomab and inotuzumab also changed outcomes in ALL. Therefore, this study reports an update of outcomes since further modification of the USC ALL pediatric-based regimen in the era of novel agents. METHODS: This is a retrospective review which included adults aged 18 years with newly diagnosed Philadelphia negative ALL (2016-2020) treated at the USC/Norris Comprehensive Cancer Center and the Los Angeles County Hospital (LAC). Primary objectives were over-all survival (OS), event-free survival (EFS), disease-free survival (DFS) at 3 years. Secondary outcomes were complete remission/complete remission with incomplete recovery (CR/CRi) and minimal residual disease (MRD) by flow cytometry rates. OS, DFS, EFS were reported through Kaplan Meier curves and Log-rank tests. Two-sided p value ≤0.05 was significant. RESULTS: 121 patients with Ph-negative ALL were reviewed (49.6% Ph-negative B-ALL, 23.9% Ph-like B-ALL, 0.8% B cell lymphoblastic leukemia (LBL), 9.1% T cell ALL, 4.1% T cell LBL, 4.1% early T-cell, 5.8% mixed phenotype acute leukemia (MPAL). Median age at diagnosis was 39.3 years. There were 71.9% Hispanic, 15.7% White, 9.9% Asian, 2.5% African Americans. 57.9% males, 42.1% females. In terms of risk stratification, the majority were unfavorable at 54.6% and 37.8% unknown. Median BMI was 29.6 kg/ m2. 52.5% had hepatic steatosis and 5% had CNS disease pre-induction. 68.7% received PEG during induction 1, and 67.9% during induction 2. Post-induction 1, 83.5% patients achieved CR/Cri with 49% MRD negativity by flow. Post-induction 2, 75% achieved CR/Cri with 57.1% MRD negativity by flow. 26.4% received blinatumomab but not allo-HSCT. 20% received blinatumomab and underwent allo-HSCT. 34.7% received blinatumomab for MRD flow positivity, median 2 cycles, only 5.8% received inotuzumab, 35.5% underwent allogenic stem cell transplant. 28.9% and 9.1% had any relapse and refractory disease, respectively. Mortality rate was at 14.9%. 3y OS was at 80.7%, 3y EFS at 54.3% and 3y DFS 61.3%. When stratified by MRD flow negativity after induction 1 and 2, 3y OS was 83.7% vs 91.1% (p=0.55), 3y DFS was 68% vs 64.1%(p=0.98) and 3y EFS was 68% vs 59.5% (p=0.84). When stratified by blinatumomab use, 3y OS 72.5% vs 85.1% (p=0.15), 3y EFS was 31.6% vs 67.5% (p=0.001), 3y DFS was 40.1% vs 73.1% (p=0.001) (Fig 1-2). Use of PEG resulted in grade 3/4 toxicities including hypersensitivity (4.1%), transaminitis (21.5%), pancreatitis (5.4%), hypertriglyceridemia (49.5%), hypofibrinogenemia (45.5%), hyperbilirubinemia (21.5%) and thrombosis (16.5%). CONCLUSIONS: The modified pediatric-based USC ALL induction regimen using PEG maintained a high 3y OS at 85.3% and appreciable 3y EFS at 54.3% and 3y DFS at 61.3%, with tolerable toxicities in an era of novel agents like blinatumomab. This compares favorably with the original USC ALL regimen, CALGB 10407 and GRAALL 2005. Of note, 3y EFS and 3y DFS were significantly lower in those who underwent blinatumomab since these patients were MRD flow positive and lacked deeper remissions, but 3y OS (72.5%) remained high regardless, even though 26.4% who received blinatumomab were not able to go for allo-HSCT. This suggests the beneficial effect of blinatumomab. Further follow-up is necessary to provide a more robust and mature survival data. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Improved Survival of Adolescents and Young Adults (AYA) Patients Aged 14-40 Years with First Relapse of Acute Lymphoblastic Leukemia Using Pediatric-Inspired Chemotherapy Salvage Protocol (R3 induction protocol)

Background: Although survival of adolescent and young adults (AYA) with acute lymphoblastic leukemia (ALL) has improved using pediatric-inspired protocols, the outcomes of those who relapse remain poor using adult chemotherapy salvage-regimens that have historically incorporated high dose Ara-C based regimen, with long term-survival of less than 10%. The CR rate with blinatumomab for salvage in adult ALL is 34% with a median survival of 7.7 months, with an OS of less than 30% at 18 months. In contrast, pediatric salvage regimens have historically been based on multi-agent therapy and have reported superior outcomes. The ALLR3 protocol for relapsed ALL in patients up to the age of 18 years reported a CR rate of 97% and an overall survival of 72%. We therefore aimed to analyze the outcomes of young adolescents and adults treated on the R3 regimen +/- blinatumomab. Methods: Seventeen AYA patients with Philadelphia-negative ALL aged between 14 and 40 years who relapsed after first-line therapy and treated with ALLR3-protocol were identified. Relapses were classed as very early (<18 months from diagnosis) early (>18m from diagnosis and <6 months from end of therapy) and late (>6 months from end of therapy). The protocol consisted of vincristine (1.5mg/m2 IV D3,10,17,24); mitoxantrone ( 10mg/m2 IV d1 &2); PEG-asparaginase (1000 u/m2 IV d3 & 17); dexamethasone (10mg/m2 BID day d1-5 and d15-20); and intrathecal methotrexate (12mg d1 & d8) were identified. Patient aged 30-40 years received L-Asparaginase instead of PEG-Asparaginase, and 8mg/m2 of dexamethasone instead of 10mg/m2. Patients' characteristics, response rate (RR) and overall survival (OS) were analyzed. Patients who achieved minimal residual disease (MRD) negative CR proceeded with an allogeneic transplant. MRD-positive patients received blinatumomab followed by a transplant. Results: The median age at relapse was 16 years (14-40 years), 88.2% of patients were B-cell ALL and 11.8% were T-cell ALL. Most patient had standard cytogenetics on presentation (76.5%) and were CNS negative (82.4%). Relapses were very early, early or late in 2 (12%) , 5 (29%) , and 7 (41%) of cases, respectively. Relapses were isolated bone marrow (BM), isolated extramedullary (EMD) or combined BM and EMD in 14 (82%),1 (6%) and 2(12%) cases, respectively. Overall complete remission (CR) rate was 60% at the end of R3 induction; CR with negative minimal residual disease (MRD negative, <10−4 cells) at the end of R3-induction was achieved in 47.1% of patients, while 11.8% of patients had CR with positive MRD (≥10−4 cells) who received Blinatumumab thereafter with eradication of MRD. Refractory disease was seen in 41.2% of patients. Almost all patients who responded to R3 proceeded to allogeneic stem cell transplant (88.8%). Eight patients died (47%), but only one patient died because of treatment-related sepsis, while the other 7 patients died because of disease-related causes. At a median follow up of 4 years, OS was 47.3%. Conclusion: Compared to traditional adult-based chemotherapy regimens and antibody therapies used in relapsed ALL, the use of pediatric-inspired protocol (R3) in relapsed AYA-ALL patients showed favorable response rates and overall survival. Further trials are required of pediatric inspired salvage regimens, preferably incorporating antibody therapies in adult patients, especially in 1st relapse. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Safety of re-challenging adults with acute lymphoblastic leukemia with PEG-asparaginase-induced severe hypertriglyceridemia when treated with a pediatric-inspired regimen.

PEG-asparaginase is used as a treatment for Philadelphia-negative acute lymphoblastic leukemia. In pediatric studies, triglycerides (TGs) were affected more by PEG-asparaginase than by native L-asparaginase (10.0%vs. 5.5%). We conducted a retrospective study to determine the safety of re-challenging adult patients with PEG-asparaginase after experiencing an episode of severe hypertriglyceridemia(>1000mg/dl or 11.4mmol/L). The incidence of hypertriglyceridemia associated with PEG-asparaginase in adult patients was high (67.5%). Therefore, checking TGs at baseline and monitoring levels while receiving PEG-asparaginase need to be considered and studied in prospective studies. However, in patients with hypertriglyceridemia not complicated by acute pancreatitis, re-challenging is safe once TG levels normalize.

ALL-269 Safety and Pharmacokinetics of Calaspargase Pegol in Adults With Newly Diagnosed Philadelphia-Negative Acute Lymphoblastic Leukemia: A Phase 2/3 Study

Asparaginase remains an important component in many adult regimens for acute lymphoblastic leukemia (ALL). In pediatric patients (<21 years), calaspargase pegol (Cal-PEG) provides sustained asparagine depletion as compared to pegaspargase, with similar rates of complete remission (CR), minimal residual disease (MRD), event-free survival (EFS), and overall survival (OS), with a similar safety profile. To confirm the recommended dose of Cal-PEG in adults (age ≥22 years) and to establish safety and PK/PD analysis. Multicenter, phase 2/3 study (NCT04817761) assessing safety and anti-leukemic activity of Cal-PEG. Part 1 enrollment commenced in Q3 2021 and will establish the safety of Cal-PEG in four groups: patients aged 22-39, 40-54, and ≥55, and patients with an elevated BMI >35 kg/m2. A minimum of 4 (initial cohort) and ~8 patients will be enrolled per group. The study will be conducted in ≤25 investigational centers in the US. Part 2 will comprise expansion cohorts after verifying safety and PK/PD analysis. Newly diagnosed patients with Philadelphia-negative B- or T-cell ALL ≥22 years with ECOG performance status 0-2, no known history of pancreatitis, coagulopathy, CNS thrombosis, or severe hepatic impairment. Approximately 114-122 patients are expected to be enrolled in the study, including 16-32 patients in Part 1. Starting doses of Cal-PEG will be based on the patients' age and BMI, with older patient groups assigned to lower doses. Patients aged≥22-39 and 40-<55 will receive Cal-PEG 2000 and 1500 U/m2, respectively. Patients with BMI >35 kg/m2 and those aged ≥55 will receive 1000 U/m2. A total of 6 Cal-PEG doses will be administered during the treatment period as part of a multiagent chemotherapy regimen based on CALGB 10403, with an end-of-treatment visit 1 year after the induction dose, and an additional 2 years of survival follow-up. The primary endpoints in part 1 are the safety of Cal-PEG, the incidence of pre-defined unacceptable toxicities within 30 days after the induction dose and achieving plasma asparaginase activity ≥0.1 U/mL 21 days after the consolidation day 43 dose. Secondary endpoints include immunogenicity, CR, end-of-induction and consolidation MRD, 1-, 2- and 3-year EFS, disease-free survival, and OS.

Digital Droplet PCR Is a Reliable Tool to Improve Minimal Residual Disease Stratification in Adult Philadelphia-Negative Acute Lymphoblastic Leukemia

Digital droplet PCR (ddPCR) is an implementation of conventional PCR, with the potential of overcoming some limitations of real-time quantitative PCR (RQ-PCR). To evaluate if ddPCR may improve the quantification of disease levels and refine patients' risk stratification, 116 samples at four time points from 44 (35 B-lineage and 9 T-lineage) adult Philadelphia-negative acute lymphoblastic leukemia patients enrolled in the GIMEMA LAL1913 protocol were analyzed by RQ-PCR and ddPCR. A concordance rate between RQ-PCR and ddPCR of 79% (P<0.0001) was observed; discordances were identified in 21% of samples, with the majority being RQ-PCR-negative (NEG) or positive not quantifiable (PNQ). ddPCR significantly reduced the proportion of PNQ samples-2.6% versus 14% (P=0.003)-and allowed disease quantifiability in 6.6% of RQ-PCR-NEG, increasing minimal residual disease quantification in 14% of samples. Forty-seven samples were also investigated by next-generation sequencing, which confirmed the ddPCR results in samples classified as RQ-PCR-PNQ or NEG. By reclassifying samples on the basis of the ddPCR results, a better event-free survival stratification of patients was observed compared to RQ-PCR; indeed, ddPCR captured more true-quantifiable samples, with five relapses occurring in three patients who resulted RQ-PCR-PNQ/NEG but proved ddPCR positive quantifiable. At variance, no relapses were recorded in patients whose follow-up samples were RQ-PCR-PNQ but reclassified as ddPCR-NEG. A broader application of ddPCR in acute lymphoblastic leukemia clinical trials will help to improve patients' stratification.