Minimal Residual Disease Negativity Rate Research Articles

Isatuximab, lenalidomide, dexamethasone and bortezomib in transplant-ineligible multiple myeloma: the randomized phase 3 BENEFIT trial.

CD38-targeting immunotherapy is approved in combination with lenalidomide and dexamethasone in patients with newly diagnosed multiple myeloma (NDMM) that are transplant ineligible (TI) and is considered the best standard of care (SOC). To improve current SOC, we evaluated the added value of weekly bortezomib (V) to isatuximab plus lenalidomide and dexamethasone (IsaRd versus Isa-VRd). This Intergroupe Francophone of Myeloma phase 3 study randomized 270 patients with NDMM that were TI, aged 65-79 years, to IsaRd versus Isa-VRd arms. The primary endpoint was a minimal residual disease (MRD) negativity rate at 10-5 by next-generation sequencing at 18 months from randomization. Key secondary endpoints included response rates, MRD assessment rates, survival and safety. The 18-month MRD negativity rates at 10-5 were reported in 35 patients (26%, 95% confidence interval (CI) 19-34) in IsaRd versus 71 (53%, 95% CI 44-61) in Isa-VRd (odds ratio for MRD negativity 3.16, 95% CI 1.89-5.28, P < 0.0001). The MRD benefit was consistent across subgroups at 10-5 and 10-6, and was already observed at month 12. The proportion of patients with complete response or better at 18 months was higher with Isa-VRd (58% versus 33%; P < 0.0001), as was the proportion of MRD negativity and complete response or better (37% versus 17%; P = 0.0003). At a median follow-up of 23.5 months, no difference was observed for survival times (immature data). The addition of weekly bortezomib did not significantly affect the relative dose intensity of IsaRd. Isa-VRd significantly increased MRD endpoints, including the 18-month negativity rate at 10-5, the primary endpoint, compared with IsaRd. This study proposes Isa-VRd as a new SOC for patients with NDMM that are TI. ClinicalTrials.gov identifier: NCT04751877 .

Acalabrutinib plus venetoclax and rituximab in treatment-naive mantle cell lymphoma: 2-year safety and efficacy analysis

This phase 1b study (NCT02717624) evaluated the safety and efficacy of acalabrutinib, venetoclax, and rituximab (AVR) in treatment-naive mantle cell lymphoma (TN MCL). Patients received acalabrutinib from cycle 1 until progressive disease or undue toxicity, rituximab for 6 cycles with maintenance every other cycle through cycle 24 or until progressive disease, and venetoclax, beginning at cycle 2, for 24 cycles. Twenty-one patients were enrolled, 95.2% completed induction (6 AVR cycles), and 47.6% continued maintenance with acalabrutinib. Thirteen (61.9%) patients had grade 3-4 adverse events (AEs), most commonly neutropenia (33.3%). Seven (33.3%) patients had COVID-19 infection (6 [28.6%] serious AEs; 5 [23.8%] deaths, all among unvaccinated patients). There were no grade ≥ 3 events of atrial fibrillation, ventricular tachyarrhythmias, major hemorrhages, or tumor lysis syndrome. Overall response rate (ORR) by Lugano criteria was 100% (95% confidence interval [CI]: 83.9, 100.0) with 71.4% complete response (CR). With median follow-up of 27.8 months, median progression-free survival (PFS) and overall survival (OS) were not reached. PFS rates at 1 and 2 years were 90.5% (95% CI: 67.0, 97.5) and 63.2% (34.7, 82.0), respectively; both were 95% after censoring COVID-19 deaths. OS rates at 1 and 2 years were 95.2% (95% CI: 70.7, 99.3) and 75.2% (50.3, 88.9), respectively; both were 100% after censoring COVID-19 deaths. Overall, 87.5% of patients with available minimal residual disease (MRD) data achieved MRD negativity (10-6; next-generation sequencing) during treatment. AVR represents a chemotherapy-free regimen for TN MCL and resulted in high ORR and high rates of MRD negativity.

Real-world evidence on treatment pattern, effectiveness, and safety of blinatumomab in Chinese patients with B-cell acute lymphoblastic leukemia

SummaryBlinatumomab is efficacious in patients with B-cell acute lymphoblastic leukemia (B-ALL), yet limited real-world data exists in this context. This retrospective study provided real-world data on the treatment pattern, effectiveness, and safety of blinatumomab in Chinese patients with newly diagnosed (ND) and relapsed/refractory (R/R) B-ALL. Patients with B-ALL who received at least one dose of blinatumomab in frontline or R/R settings between August 2021 and June 2023 were included. The primary outcome was the treatment pattern of blinatumomab. Key secondary outcomes included complete remission (CR)/CR with incomplete blood cell recovery (CRi) rate, minimal residual disease (MRD) negativity, median event-free survival (EFS), and safety. The study included 96 patients with B-ALL; 53 (55.2%) patients were in the ND group and 43 (44.8%) patients were in the R/R group. The median treatment duration was one cycle (range: 1–5). Most patients underwent chemotherapies, allo-HSCT, or experimental CAR-T following blinatumomab. The ND patients using blinatumomab induction therapy achieved 100% CR/CRi rate; 87.2% achieved MRD negativity within two cycles of blinatumomab. In R/R re-induction patients, the CR/CRi rate was 50%; MRD negativity rate was 64.2%. In R/R patients using blinatumomab for consolidation, MRD negativity rate was 90.9%. The median EFS was not reached in both ND and R/R patients; 1-year EFS rate was 90.8% (95% CI: 67%, 97%) and 55.1% (95% CI: 30%, 74%), respectively. Grade ≥ 3 adverse events were observed in 12.5% patients. Blinatumomab was found to be effective with a tolerable safety profile in real world setting.

Limited efficacy of 3 + 7 plus gemtuzumab ozogamycin in newly diagnosed fit intermediate genetic risk acute myeloid leukemia patients.

Gemtuzumab-ozogamycin (GO) is approved in combination with high-dose chemotherapy for treatment-naïve low- and intermediate-risk acute myeloid leukemia (AML). In this retrospective real-life multicenter study, we reported efficacy and safety of GO plus high-dose chemotherapy in newly diagnosed AML patients. A total of 31 fit low- and intermediate-risk AML patients treated with GO-based regimens were retrospectively included in this real-life multicenter study, and results were compared with a control cohort treated with 3 + 7 alone. Complete remission (CR) rate after induction was 77%, and most responders (45%) underwent two GO-based consolidation, and minimal residual disease (MRD) negativity was observed in 17 cases (55%) after the end of consolidation. Low genetic risk was associated with increased CR rate compared with intermediate-risk AML (88% vs. 33%; p < .001), as well as prolonged overall survival (OS; hazard ratio, 0.16; 95% confidential interval, 0.02-0.89; p < .001). GO addition resulted in a survival benefit for low-risk AML (median OS not reached vs. 25 months; p = .19) while not for intermediate-risk subjects (10 vs. 13 months; p = .92), compared with the control group. Moreover, GO-treated patients experienced fever of unknown origin or sepsis in 42% or 36% of cases, respectively, with one death during induction due to septic shock, with similar rates compared with the control group (p = .3480 and p = .5297, respectively). No cases of veno-occlusive disease after allogeneic transplantation were observed. Our real-life multicenter study confirmed GO-based treatment efficacy with high MRD negativity rates in fit newly diagnosed AML patients, especially in those with low genetic risk and core binding factor, while limited benefits were observed in intermediate-risk AML. However, further validation on larger prospective cohorts is required.

Abstract 5071: Minimal residual disease (MRD) status by peripheral blood mononuclear cells (PBMCs) and circulating tumor DNA (ctDNA) demonstrates rapid, deep, and sustained response in patients (Pts) with relapsed/refractory follicular lymphoma (R/R FL) treated with subcutaneous (SC) epcoritamab monotherapy in the pivotal phase 1/2 EPCORE™ NHL-1 trial

Abstract Introduction: Outcomes in high-risk R/R FL are poor. Epcoritamab SC, a CD3xCD20 bispecific antibody, demonstrated promising efficacy with a manageable safety profile in pts with R/R FL after ≥2 prior lines of therapy (phase 1/2 EPCORE NHL-1; NCT03625037). Here we evaluated MRD with PBMCs and ctDNA in pts with R/R FL and correlated the results with clinical findings. Methods: Adults with R/R FL 1-3A enrolled in EPCORE NHL-1 received epcoritamab SC in 28-day cycles. MRD analysis was performed on longitudinal plasma and PBMC samples collected at prespecified timepoints (clonoSEQ assay, Adaptive Biotechnologies). Screening tumor biopsies were used to identify trackable tumor clones; samples were quantified as tumor clones detected per mL plasma for ctDNA and per one million nucleated cells for PBMC. Overall response and progression-free survival (PFS) were assessed using Lugano criteria by independent review committee. Results: Of 128 pts in the R/R FL 1-3A cohort, 91 with PBMC data and 100 with ctDNA data were MRD evaluable. Overall MRD negativity was achieved in 67.0% [95% CI: 56.4-76.5] of pts per PBMC and 68.0% [95% CI: 57.9-77.0] of pts per ctDNA. Concordance of subject-level MRD status was high (79 of 89 with PBMC and ctDNA data; 88.8%). In most pts, MRD negativity was reached prior to radiographic complete response (PBMC, 76.4%; ctDNA 58.5%). MRD negativity by PBMC preceded ctDNA (median days to MRD negativity, 28 [PBMC] vs 57 [ctDNA]), suggesting a difference in methodology in detecting tumor DNA. Pts who became MRD negative had prolonged PFS (median not reached). Baseline MRD levels were not associated with clinical outcomes (PBMC; Wilcoxon P=0.59, ctDNA P=0.39). PFS was similar in pts achieving MRD negative status (median not reached, PBMC and ctDNA), independent of high-risk/difficult-to-treat disease (≥4 prior lines, Ann Arbor stage III-IV, bulky disease, double refractory, FLIPI 3-5, and POD24). The overall MRD negativity rate was also similar in high-risk pts, except those with ≥4 prior lines of therapy. Conclusions: Based on the EPCORE-NHL-1 study, one of the first pivotal studies to report MRD in pts with R/R FL, epcoritamab drives rapid, deep, and sustained responses as supported by MRD assessment by both PBMC and ctDNA. MRD results correlate with clinical outcome, and achieving MRD negativity is associated with longer PFS. PFS was similar among all pts who achieved MRD negativity, including those with high-risk disease. Citation Format: David Soong, Işıl Altıntaş, John Karavitis, Kim M. Linton, Wojciech Jurczak, Catherine Thieblemont, Kevin Zhao, Edith Szafer-Glusman, Daniela Hoehn, Elena Favaro, Mariana Sacchi, Maria Jure-Kunkel. Minimal residual disease (MRD) status by peripheral blood mononuclear cells (PBMCs) and circulating tumor DNA (ctDNA) demonstrates rapid, deep, and sustained response in patients (Pts) with relapsed/refractory follicular lymphoma (R/R FL) treated with subcutaneous (SC) epcoritamab monotherapy in the pivotal phase 1/2 EPCORE™ NHL-1 trial [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 5071.

Venetoclax plus a hypomethylating agent versus cytarabine, aclarubicin, and granulocyte colony-stimulating factor chemotherapy as a first-line therapy for newly diagnosed acute myeloid leukemia: A propensity score-matched analysis.

Both venetoclax plus a hypomethylating agent (VEN/HMA) and cytarabine, aclarubicin, and granulocyte colony-stimulating factor (CAG) are low-intensity regimens for older patients with acute myeloid leukemia (AML) that show good efficacy and safety. It is unknown how VEN/HMA compares with the CAG regimen for the treatment of newly diagnosed AML. The outcomes of patients with newly diagnosed AML treated with VEN/HMA were compared with those of patients treated with a CAG-based regimen. Propensity score matching between these two cohorts at a 1:1 ratio was performed according to age at diagnosis, sex, Eastern Cooperative Oncology Group performance status, state of fitness, and European LeukemiaNet (ELN) 2022 risk stratification to minimize bias. A total of 84 of 96 patients in the VEN/HMA cohort were matched with 84 of 147 patients in the CAG cohort. VEN/HMA resulted in a better response than the CAG-based regimens, as indicated by a higher composite complete remission (CRc) rate (82.1% vs. 60.7%; p=.002) and minimal residual disease negativity rate (88.2% vs. 68.2%; p=.009). In patients with an ELN adverse risk, VEN/HMA was associated with a higher CRc rate compared to CAG (80.5% vs. 58.3%; p=.006). VEN/HMA was associated with longer event-free survival (EFS) (median EFS, not reached vs. 4.5 months; p=.0004), whereas overall survival (OS) was comparable between the two cohorts (median OS, not reached vs. 18 months; p=.078). The VEN/HMA regimen may result in a better response than CAG-based treatment in older patients with newly diagnosed AML.

Clinical efficacy and safety of flumatinib versus dasatinib combined with multi-drug chemotherapy in adults with Philadelphia-positive acute lymphoblastic leukemia

Introduction: Flumatinib, a highly selective ABL kinase inhibitor, exhibits stronger inhibition of intracellular BCR-ABL tyrosine kinase activity, compared to Imatinib. However, there is limited research comparing the real-world efficacy and safety of flumatinib and dasatinib in patients with Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL). Objective: Investigating the differences in therapeutic efficacy and safety between flumatinib and dasatinib in combination with multi-drug chemotherapy for the treatment of newly diagnosed Ph+ ALL. Method: In this study, we assessed 43 patients with newly diagnosed Ph+ ALL (20 in the flumatinib group, 23 in the dasatinib group). Results: There were no significant differences in gender, age, fusion gene type, initial blood routine, bone marrow blast cell ratio or chromosome karyotype between the two groups. Within 1 month, there were no significant differences in the complete response (CR), major molecular response (MMR) or minimal residual disease (MRD) negativity rate between the flumatinib and dasatinib groups. Similarly, within 3 months, there were no significant differences in CR or MMR rates between the two groups. However, the rates of complete molecular response (CMR) and MRD negativity within 3 months were significantly higher in the flumatinib group, compared to the dasatinib group (P < 0.05). Additionally, the flumatinib group exhibited fewer adverse reactions compared to the dasatinib group. Conclusion: These findings suggest that flumatinib is a safe and effective tyrosine kinase inhibitor (TKI) for achieving CMR and MRD negativity in patients with Ph+ ALL, as supported by this small series of patients.

Low-Dose IA with Venetoclax Regimen As Induction Therapy for Newly Diagnosed Acute Myeloid Leukemia

Abstract Background: The IA regimen (combination of idarubicin and cytarabine) is used as the most common induction of remission therapy for acute myeloid leukemia, with the complete response (CR) rates of up to 70%. Addition of the BCL-2 inhibitor venetoclax(Ven) to chemotherapy can increase apoptosis priming. In order to further improve the remission rate and prolong survival, our center uses a low-dose IA regimen combined with Venetoclax to treat newly diagnosed primary acute myeloid leukemia under 60 years old. Methods: We retrospectively analyzed 15 patients with newly diagnosed AML, who was under 60 years old. Patients received idarubicin (6mg/m2 IV for 3-days) and cytarabine (60mg/m2 IV for 5-days) with oral venetoclax (400mg daily for 2 weeks) for induction, followed by the same chemo-free regimen for consolidation if patients responded to induction therapy. And then analyze the effects of this regimen on complete remission (CR) rate, minimal residual disease (MRD) negative CR rate, relapse-free survival (RFS), overall survival (OS), and adverse events. Findings: Between January, 2021 and June, 2023, 15 patients were treated with this regimen. The median age was 43 years (IQR, 36-43) and the median follow-up was 4.25 (IQR, 2.73-15.6) months. Among all patients, the ORR was 86.7% (95% CI 62, 96), the CR rate was 80.0% (95% CI 55, 93), and the MRD negative rate was 66.7% (95% CI 42, 85). According to 2022 ELN risk classification by genetics, the ORR in favorable risk patients were 50.0% (1/2), intermediate risk patients were 100% (7/7), adverse risk patients were 83.3%(5/6). Those who had epigenetic modification mutations (NPM1, FLT3-ITD, CEBPA) were more likely to benefit from this regimen. The most common grade 3 and 4 adverse reactions were neutropenia, thrombocytopenia, and anemia. Conclusion: As induction and consolidation therapy whose adverse reactions were tolerable, the low-dose IA with Venetoclax regimen produces deep remission for the patients with newly diagnosed primary AML.

A Phase II Study of Zanubrutinib-Based Induction and Maintenance Therapy in Young and Fit Patients with Untreated Mantle Cell Lymphoma (BRIDGE): An Updated Analysis with Long-Term Follow up

Introduction Studies showed that remission after induction therapy is associated with better prognosis in mantle cell lymphoma (MCL) patients, and minimal residual disease (MRD) is also considered as an independent and sensitive factor in MCL patients. As R-CHOP/R-DHAOx is the most common used induction regimen in China, we investigate the benefit of zanubrutinib-based induction (zanubrutinib plus R-CHOP) in untreated young MCL patients. We previously reported a promising result of an ORR of 100% with MRD negative rate of 100% after induction treatment in 2022 PPLC. Here, we reported a long-time (median follow-up: 25.9 months) efficacy and safety in the study. Methods In this prospective, single-center, single-arm, phase II study (NCT04736914), patients aged 18-65 years with previously untreated, Ann Arbor stage II-IV, histologically confirmed MCL will be enrolled to alternately receive R-CHOP + zanubrutinib and R-DHAOx induction for 6 cycles (every 21 days per cycle). Zanubrutinib will be administered in cycle 1, 3, 5 (R-CHOP), 160 mg BID, d1-21, and not in combination with R-DHAOx. Patients who achieve remission (≥PR) will be allowed to proceed to ASCT or maintenance depending on the investigator's evaluation and discretion. In patients who do not achieve a remission at the end of induction (treatment failure), no specific treatment is defined; rather, the further salvage treatment is upon the discretion of investigators. Patients will receive zanubrutinib maintenance for two years in case of remission at ASCT assessment or end of induction assessment. Zanubrutinib is administrated orally at 160 mg BID, continuously for 2 years or until progressive disease, unacceptable toxicity, or death, whichever occurs first. The primary endpoint was bone marrow MRD negative rate after induction therapy (at the completion of cycle 6 or at premature discontinuation). Results A total of 7 patients were enrolled, the median age was 56.3, and bone marrow (BM), peripheral blood (PB) MRD showed positive at baseline. After 6 cycles of R-CHOP + zanubrutinib and R-DHAOx induction treatment, BM and PB MRD negative rate was 100% (7/7). One patient proceeded to ASCT. At the data cut-off date of 30 Jun 2023, one patient has completed the study at week 53 with zanubrutinib maintenance treatment due to the progressive disease, while the other 6 patients remain in the zanubrutinib maintenance treatment and are still under follow-up (Figure). With a median follow-up of 25.9 months, all patients showed good tolerance, with no dose modification and discontinuation during zanubrutinib-based induction therapy, either no BTKi interested AE (includes diarrhea, hypertension, major hemorrhage, and atrial fibrillation/flutter) was observed (Table). Conclusions This prospective, phase II study with a relatively longer follow-up duration estimated the treatment regimen in untreated young MCL patients. At the time of data cut-off, zanubrutinib-based induction therapy was well tolerated in all patients and showed a promising results in response and MRD. With a median treatment duration of 16.6 months, most patients (6/7) did not relapse. The study is ongoing and further results will be continuously released.

Zanubrutinib and Venetoclax As Initial Therapy for CLL/SLL with Obinutuzumab Triplet Consolidation in Patients with Minimal Residual Disease Positivity (BruVenG)

Background: Bruton's tyrosine kinase inhibitors (BTKi), anti-CD20 antibodies, and B cell lymphoma 2 inhibitors (BCL-2i) are essential therapeutic drug classes in the treatment of chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). Clinical synergy of BTKi and BCL-2i combinations have been observed, which allow for an oral regimen, that can be safely administered in a clinic setting for most patients (Tam et al., 2022; Wierda et al., 2021). Still, it remains uncertain if anti-CD20 antibodies meaningfully add to the effectiveness of oral combination therapy. Recent reports of triplet regimens demonstrate modest improvement in minimal residual disease (MRD) negativity with similar response rates when compared to oral doublets (Davids et al., 2021; Soumerai et al., 2021; Wierda et al., 2021). Additionally, anti-CD20 antibody use causes significant B cell depletion resulting in prolonged immune suppression. Recent reports suggest BTKi use may in fact impair clinical activity of anti-CD20 antibodies, which can be mitigated by using selective BTKi and incorporating anti-CD20 later in the treatment course when lower disease burden is present (Da Roit et al., 2015; Flinsenberg et al., 2020; Pavlasova et al., 2016; Rawstron et al., 2018). Therefore, anti-CD20 therapy may not be required for all patients and could be optimized within a response-adapted strategy. This trial has been developed to assess efficacy and safety of a response adapted consolidative treatment approach utilizing obinutuzumab triplet consolidation in CLL/SLL patients who remain MRD positive after an oral doublet fixed duration treatment with zanubrutinib and venetoclax. This approach looks to maximize MRD negative remissions, spare toxicity by limiting anti-CD20 exposure, and provide a finite therapy. This study will utilize once daily zanubrutinib for which there is limited data in regard to safety and efficacy particularly in combination with venetoclax. Study Design and Endpoints: This is a single center, open label, phase II, investigator initiated clinical trial enrolling 50 subjects evaluating the efficacy and safety of zanubrutinib and venetoclax with obinutuzumab triplet consolidation in subjects who remain MRD positive (BruVenG). Eligible patients must have treatment naïve CLL/SLL and treatment indications per the International Workshop on CLL 2018 guidelines. Subjects with Richter's transformation are excluded. Treatment will consist of lead-in, combination, and consolidation phases. All subjects will be treated with a 3-cycle lead-in of 320mg oral, once daily zanubrutinib monotherapy. Venetoclax will be incorporated at cycle 4, per the standard prescriber insert ramp-up schedule. A final dose of 400mg oral, once daily venetoclax, in combination with 320mg oral, once daily zanubrutinib will be used in all subsequent cycles after ramp-up. At cycle 16, MRD will be assessed in the peripheral blood (PB) and bone marrow (BM) via clonoSEQ (Adaptive Biotechnologies). Subjects who are MRD negative (&amp;lt;1x10 -4 ) in both compartments will stop therapy. Subjects who are MRD positive in PB or BM will continue zanubrutinib and venetoclax for an additional 6 cycles. Obinutuzumab will be added to the oral doublet starting at cycle 17. Standard intravenous obinutuzumab lead-in will occur during cycle 17, followed by standard monthly intravenous dosing of 1000mg through cycle 22. Depending on MRD status, subjects will be treated for 16 or 22 cycles. All subjects who receive consolidation will stop treatment at cycle 23 regardless of end of treatment MRD status. The primary endpoint is cycle 16 PB and BM MRD negativity rates. A co-primary endpoint will be cycle 23 PB and BM MRD negativity rates in subjects who were MRD positive at C16 and who went on to receive at least 1 dose of obinutuzumab. Key secondary endpoints will include cycle 16 overall response rate, 36-month progression free survival, 36-month overall survival, 36-month time to next treatment, 24- and 36-month PB MRD negativity rates, tumor lysis risk reduction rates, and safety. Exploratory endpoints will assess the positive predicative value of the ∆400 biomarker (Soumerai et al., 2021) on MRD negativity at cycle 16. This biomarker will be assessed between cycle 4 and 6. The MRD negative rates at cycle 16 and cycle 23 will be estimated with a 90% confidence interval using the Clopper-Pearson method based on exact binomial distribution.

MRD Monitoring By Euroclonality IGH Based NGS Approach Predicts Outcome in Follicular Lymphoma Patients Lacking a Conventional BCL2::IGH Marker: A Substudy from the Fondazione Italiana Linfomi (FIL) FOLL12 Trial

Background. Despite durable clinical responses achieved by chemo-immunotherapy in follicular lymphoma (FL) patients, most of them eventually relapse. Actually, minimal residual disease (MRD) analysis based on the detection of BCL2::IGH rearrangement by PCR is the most widely used and standardized approach, able to early identify patients at high risk of disease reappearance. Nevertheless, this tool fails the molecular marker definition in up to 45% of cases, hampering the disease monitoring in a large group of patients. In the last decade, the continuous improvement of next-generation sequencing (NGS) techniques allowed to introduce these novel tools for MRD monitoring in some hematologic diseases, as acute lymphoblastic leukemia and multiple myeloma, thus reducing PCR limitations and increasing the number of patients eligible for MRD. Nonetheless, applications of NGS tools for MRD detection in FL are still scant. Aims. Therefore, we tested the feasibility of the EuroClonality (EC) IGH-based NGS approach [Brüggeman, Leukemia 2019] to identify novel molecular markers suitable for MRD monitoring in the context of the large prospective trial “FOLL12” (EudraCT: 2012-003170-60) by the Fondazione Italiana Linfomi (FIL), where 57% of patients were already studied for MRD by classic PCR methods targeting the BCL2::IGH rearrangement.[Luminari, JCO2022] Methods. Advanced FL patients received upfront treatment with either R-CHOP or BR, followed by a combined PET/MRD response-based maintenance with rituximab. Bone marrow (BM) samples were centralized to the FIL MRD Network for standardized MRD analysis. Baseline gDNA of “no marker” patients was screened by IGH-based NGS using EC-IGH two-steps PCR approach in the EuroMRD certified lab of Torino university; then MRD was monitored in those patients harboring a IGH clonal marker at baseline by one step EC-IGH method. The identification of baseline clonotypes and MRD clones was performed by ARRest/Interrogate tool. Results. 343/786 enrolled patients (43%) lacked a conventional BCL2::IGH marker and 161/343 (47%) showed morphologic BM lymphoma infiltration: of these, 124 (77%) had an available BM baseline sample for IGH screening and were thus included in the analysis. Overall, IGH clonotypes suitable as novel molecular markers were identified in 75/124 patients (60%), of which 73 monoclonal and 2 biclonal. Of this series, 47 patients had centralized a BM sample for MRD analysis at end of induction. Median age of this subset was 59 years (33-81), 53% were female, all were Ann Arbor stage IV, 34% were FLIPI intermediate and 43% high risk, respectively. Moreover, 56% received R-CHOP and 44% BR as induction treatment, resulting in a 79% CR rate and 89% MRD negativity rate (in line with the results of the general trial population). PFS at 3 years for this series was 69%: however, the 5 patients who scored MRD positive (MRD+) showed statistically significant worse PFS at 3 years than MRD negative cases (22% vs 73%, respectively, p=0.0069, Figure 1). Notably, 4 out of 5 MRD+ patients experienced POD24. Focusing on biclonal cases, one presented superimposable MRD trends between clones (both achieving MRD negativity), while in the other both clones remained MRD positive but showing one Log difference between them. Interestingly, only one of the two clones showed a MRD increase in the following timepoint (6 months after end of induction), heralding the clinical relapse subsequently occurred at month 12 (Figure 2). On the other hand, no IGH clonotype was identified in the first 17 patients who were screened for a novel MRD marker despite the absence of BM infiltration. Conclusions. The first data on the large-scale application of NGS-based marker screening tools in FL patients lacking a conventional BCL2::IGH marker for MRD enrolled in a prospective clinical trial showed that the EC IGH-based NGS approach was able to provide a new molecular marker in 60% of patients with evidence of BM infiltration (that means about the 28% of “no marker” FL patients); importantly, this approach was predictive of worse PFS for MRD+ cases. Overall, these data are promising for the wide employment of novel, effective MRD monitoring tools, able to recover more than one fourth of FL patients lacking a conventional molecular marker and so, by combining conventional and NGS-based techniques, potentially rising the percentage of MRD evaluable cases up to at least 70% cases.

Will Survival Improve By Treating Multiple Myeloma Patients at MRD Relapse? the Remnant Study

Background: Although many new treatment options have become available, multiple myeloma (MM) is still considered an incurable disease. The importance of achieving minimal residual disease (MRD) negativity in MM patients has become clearer in recent years. Multiple studies show that bone marrow based MRD assessment is one of the strongest prognostic factors, and deeper responses correlate with more favorable outcomes. The REMNANT study will evaluate if treating at MRD relapse after first line (1.L) treatment prolongs progression-free survival (PFS) and overall survival (OS) in MM patients. Methods: The REMNANT study (RElapse from Mrd Negativity As iNdication for Treatment) is an academic, multicenter, open-label, randomized phase 2/3 study of newly diagnosed (ND) MM patients eligible for autologous stem cell transplant (ASCT). The study has a population-based approach with few exclusion criteria, implying that patients with kidney failure, amyloidosis, plasma cell leukemia and other comorbidities are enrolled. To increase enrollment in part 2, patients who have received 1.L treatment outside the REMNANT study can be enrolled directly if they are &amp;gt;CR/MRD negative. 391 NDMM patients (age 18-75 years) eligible for ASCT will be enrolled in part 1 (phase 2) of the study and receive standard of care Norwegian 1.L treatment; 4 pre-transplant induction and 4 post-transplant consolidation cycles of bortezomib, lenalidomide and dexamethasone (VRd). After induction, patients will undergo tandem or single transplant, depending on toxicity and response to first transplant. All patients receive lenalidomide maintenance. Following 1.L treatment 176 patients achieving MRD negative (Euroflow NGF 10 -5) complete response will be enrolled in part 2 (phase 3) of the study. Patients will be randomized in a 1:1 ratio to receive second line treatment (2.L) at MRD relapse in arm A or at PD in arm B. At loss of MRD negativity in arm A or at PD in arm B, 2.L treatment will be daratumumab, carfilzomib and dexamethasone until PD. The primary endpoint of part 1 (phase 2) of the study is the number of patients who achieve MRD negative (Euroflow NGF 10 -5) complete response 30-45 days post consolidation. Secondary endpoints includes response rates, safety evaluations and patient-reported outcome. The co- primary endpoints in part 2 (phase 3) are PSF and OS from randomization to progressive disease or death on 2.L treatment. We will also compare different methods for measuring MRD: NGF Euroflow, Next Generation Sequencing, mass spectrometry and PET-CT. We want to evaluate how the different methods compare when it comes to sensitivity and outcome (PFS and OS). Results: As of July 18 th 2023, 291 patients are enrolled in part 1 and 97 in part 2 (23 directly enrolled). Baseline characteristics, safety summary and preliminary results can be found in Table 1. The ORR on first line treatment is 95% and 65 of 152 patients (45%) were &amp;gt;CR and MRD negative at the post-consolidation visit. Patients achieving &amp;gt; VGPR but not CR MRD negativity post consolidation are followed for up to 24 months on lenalidomide maintenance, and 11 of 74 patients (15%) in follow-up have converted to &amp;gt;CR/MRD negativity at a median time of seven months (range 2-16). Nine patients have started 2.L treatment in part 2 (phase 3), eight in arm A (MRD guided) and one in arm B (control arm). Median time to loss of MRD negativity among the eight patients in arm A was four months (range 1-6). The most common adverse events were infections, occurring in 24% of patients (any grade). During 1.L treatment, 61 patients have left the study. Seven patients have died, 27 discontinued due to disease progression, 12 patients have withdrawn from the study and seven discontinued due to adverse events. 59% of the patients who progressed during 1. L treatment had high-risk cytogenetics (with gain1q and/or del17p and/or t(4;14)). Conclusion: Standard of care Norwegian first line treatment has an ORR of 95%. The MRD negativity rate among patients who have finished 1.L treatment was 43% (65 of 152). The median time to loss of MRD negativity in arm A (MRD guided) was 4 months.

Safety and Efficacy Outcomes for Patients with High-Risk Multiple Myeloma Receiving Idecabtagene Vicleucel: The MD Anderson Experience

Background: There is a paucity of data regarding the impact of high-risk features on the efficacy and safety of B-cell maturation antigen (BCMA)-directed autologous chimeric antigen receptor (CAR)-T therapy in patients with multiple myeloma (MM). Methods: In this retrospective single-center study we included all MM patients who received idecabtagene vicleucel (ide-cel) between 12/2019-10/2022, either in the setting of a clinical trial (i.e. KarMMa-2 and KarMMa-3) or as a standard of care (SOC). We evaluated the impact of high-risk disease features on the efficacy and safety outcomes. Patients with high-risk MM (HRMM) were defined as having at least one of the following: high-risk cytogenetic abnormalities prior to CAR-T infusion (deletion 17p, translocation (t)(4:14), t(14:16) or 1q gain/amplification (1q+)), extramedullary disease (EMD), plasma cell leukemia and Revised International Staging System (R-ISS) stage 3. Minimal residual disease (MRD) was evaluated using 8-color next-generation flow cytometry (NGF), with a sensitivity of 1/10-5 cells (0.001%) based on the acquisition and analysis of at least 2 million events. Efficacy outcomes included response rates, progression free survival (PFS) and overall survival (OS). Safety outcomes included incidence/grade of cytokine release syndrome (CRS), Immune effector cell-associated neurotoxicity syndrome (ICANS), hematological toxicity and infections. Results: A total of 74 patients were included in our analysis, 49 received SOC ide-cel and 25 were treated on clinical trial. The median age was 65.3 (range 37.9-90.3) years, and 49 patients (66%) were male. Median number of previous lines of therapy was 6 (range 1-18). The HRMM group included 52 patients (70%), and the most prevalent high-risk features were high-risk cytogenetic abnormalities (43%, most often 1q+ (n=26, 81%), followed by del17p (n=17, 33%), t(4:14) (n=9, 17%) and t(14:16) (n=4, 8%)) and EMD (19%). Seventy five percent of patients who received SOC ide-cel had HRMM compared to 25% of those who received ide-cel on clinical trial (p=0.014). Compared to patients with standard-risk MM (SRMM), those with HRMM more often had disease refractory to proteasome inhibitors (p=0.042) or anti-CD38 antibodies (p=0.01), and more often received bridging therapy prior to CAR-T infusion (p=0.021). After bridging therapy, 43% of HRMM patients had progressive disease, compared to 20% of SRMM patients (p=0.21). Sixty seven percent of the entire cohort received prior BCMA-directed therapy before ide-cel, without a significant difference between the two risk groups (p=0.80) ( Table 1). For the entire cohort, overall response rate was 85%, and 51% achieved ≥CR at best response. There was no significant difference between the HRMM and SRMM groups in response rates or in rates of MRD negativity at day 30 and at 3/6/9 months after CAR-T infusion, yet fewer HRMM had MRD negativity at 12 months after CAR-T (50% vs. 100% of evaluable patients, p=0.019). The 6-months PFS for the HRMM group and the SRMM group was 64% and 81%, respectively (p=0.11) ( Figure 1A), and the 6-months OS was 80% and 90%, respectively (p=0.067) ( Figure 1B); Thirty-nine patients in the HRMM group developed CRS (83% of evaluable patients), including one grade 3 and one grade 5 CRS, compared to 15 (75%, p=0.65) in the SRMM group (all grade &amp;lt;3). Eight patients in the HRMM group developed ICANS (17%), including two grade 4 ICANS, compared to 3 (15%, p=0.93) in the SRMM group (all grade &amp;lt;3). We did not observe a difference in rates of neutropenia (p=0.63), anemia (p=0.75) or thrombocytopenia (p=0.53) by day 30, and also not in the rates of infection (p=0.16) between the two groups. In multivariate analysis on the entire cohort, receiving &amp;lt;4 prior lines of therapy (HR 0.06, 95% CI 0.004-0.71, p=0.026) and ECOG≤2 (HR 0.07, 95% CI 0.08-0.53, p=0.01) were associated with superior OS. Conclusions: Patients with HRMM receiving ide-cel had mostly comparable response rates compared to those with SRMM. HRMM patients had numerically worse PFS and OS compared to patients with SRMM, though not reaching statistical significance. Overall rates of CRS/ICANS were comparable between the two groups, yet only patients with HRMM had grade ≥3 of these complications. Patients who received ide-cel after less than four previous lines of therapy had better overall survival.

Sequential Chemotherapy and Blinatumomab to Improve Minimal Residual Disease in Adult Ph- B-Lineage Acute Lymphoblastic Leukemia. Final Results of the Phase II Gimema LAL2317 Trial

Introduction. The outcome of adult patients with acute lymphoblastic leukemia (ALL) has markedly improved following the introduction of a pediatric inspired chemotherapy backbone coupled with minimal residual disease (MRD) monitoring at well-defined timepoints (TP), translating into a rational patients' stratification for allogeneic transplantation (Tx). Immunotherapy, in particular blinatumomab, represents a further advancement in the management of ALL. We designed a phase II trial (GIMEMA LAL2317) for adult Ph- CD19+ B-lineage ALL (Ph- B-ALL) consisting of a pediatric chemotherapy backbone - with dose adjustment in patients &amp;gt;55 years - to which 2 cycles of blinatumomab were added, the first after early consolidation cycle 3 (high-dose methotrexate and Ara-C) and the second after late consolidation cycle 6. Tx allocation was based on MRD assessment, carried out in most cases by RQ-PCR and by flow cytometry when a sensitive molecular marker was not identified. The primary objective of the trial was to assess the impact of blinatumomab in increasing the rate of early MRD negativity at end of week 14 (TP3). Patients and methods. The protocol was designed for adults up to the age of 65 years with newly diagnosed Ph- B-ALL; 149 patients were enrolled. Median age was 41 years (18-65), with 28 patients (19%) being older than 55. Eighty-one patients were males, and the median white blood count (WBC) was 4.5x10 9/l (1-474); 12 cases harbored the KMT2A rearrangement, 5 the TCF3:: PBX1 transcript and 31 were classified as Ph-like according to the BCR/ABL1-like predictor . The median follow-up is 37.5 months (0.55-62.8) Results. At the end of induction (TP1, after cycles 1 and 2), 131 patients (88%) were in complete remission (CR), with a significant difference according to age: 94%, 92% and 64% in the 18-40, 40.55 and &amp;gt;55 years cohorts, respectively (p&amp;lt;0.001). All patients with KMT2A and TCF3::PBX1 rearrangements achieved a CR, while 5 Ph-like patients did not. At TP2, i.e. after early consolidation, 85 patients (70%) became MRD-negative (MRD neg). TP3, after the 1 st blinatumomab cycle, 102 patients were MRD neg; the rate of MRD negativity increased to 93% (p&amp;lt;0.001). Imposable results were obtained considering only paired MRD samples. Eight patients remained MRD pos, including 4 with a KMT2A rearrangement and 1 with a E2A::PBX1 rearrangement. OS and DFS at 36 months are 71% and 66% on the whole cohort. OS was significantly different (p=0.00013) according to age cohorts: 76%, 74% and 49% for patients aged 18-40, 40-55 and &amp;gt;55 years, respectively. Likewise, DFS was 71%, 62% and 42% for the same age cohorts, without reaching statistical significance. When patients were stratified for TP2 MRD, OS and DFS were significantly better for MRD neg vs MRD pos cases (p=0.0006 and p&amp;lt;0.0001, respectively). At variance, at TP3, with the caveat of the small sample size of MRD pos patients, the differences between MRD neg and MRD pos patients at TP3 were abolished: indeed, OS and DFS were 82% and 68% for MRD neg, 80% and 70% for MRD pos and 88% and 72% for those lacking MRD evaluation (Figure). Finally, 30 relapses have so far occurred, including 10 Ph-like, 1 KMT2A and 3 TCF3::PBX1 rearranged cases. The overall cumulative incidence of relapse (CIR) was 27.5%; of note, within TP3 MRD neg patients CIR was 42.5% in Ph-like cases vs 17.5% in the remaining patients. By univariate analysis, significant factors for OS were age (p&amp;lt;0.001), CR achievement (p&amp;lt;0.001) and TP2 MRD (p=0.002); TP2 MRD retained significance in multivariate analysis (p=0.001). Univariate analysis for DFS showed as significant the Ph-like signature (p=0.026) and TP2 MRD (p&amp;lt;0.001); both retained statistical significance in multivariate analysis (p=0.021 and &amp;lt;0.001, respectively). Toxicity details will be provided. Conclusions. This phase II trial shows the benefit of adding blinatumomab for the management of Ph- B-ALL, with the primary objective being achieved with 93% of patients being MRD neg after the 1 st cycle of blinatumomab. With a median follow-up of 37.5 months, OS and DFS are 71% and 66%, respectively, better than in historical results, particularly in patients up to the age of 55. Importantly, at TP3 the MRD status no longer impacted, highlighting the therapeutic role of blinatumomab, as observed in Ph+ ALL. Finally, the Ph-like signature retains its negative prognostic impact, suggesting that a combination strategy, similar to that in place for Ph+ ALL, is required.

Reduced-Dose Chemotherapy Followed By Blinatumomab As Induction Therapy in Treatment of Newly Diagnosed Philadelphia Chromosome-Negative B-Cell Precursor Acute Lymphoblastic Leukemia - Interim Results from a Multicenter, Single-Arm, Phase 2 Study

Introduction: Although intensive pediatric chemotherapeutic regimens have shown good efficacy in the treatment of Philadelphia Chromosome-negative (Ph-negative) B-cell precursor acute lymphoblastic leukemia (BCP-ALL) in adults, the high incidence of chemotherapy-related toxicities limits their use. Blinatumomab, a CD3/CD19 bispecific T-cell antibody, has shown high efficacy in relapsed/refractory or minimal residual disease (MRD) positive BCP-ALL; however, the efficacy of single-agent blinatumomab does not meet the treatment needs of adult patients. Therefore, combining low-intensity chemotherapy with blinatumomab could be a better induction regimen for newly diagnosed adult patients with BCP-ALL. Methods: This multicenter, single-arm, phase 2 trial (NCT05557110) enrolled adult patients (aged 15-59 years) with newly diagnosed Ph-negative BCP-ALL. The induction regimen comprised reduced intensity chemotherapy (idarubicin 8 mg/m 2 on day 1, vindesine 4 mg on day 1, and dexamethasone 9 mg/m 2/day from day 1-7) followed by 2 weeks of blinatumomab (9 ug/day from day 8-14, 28 ug/day from day 15-21). The primary endpoint was to assess the overall response rate (ORR=complete remission [CR] + CR with partial hematologic recovery [CRh] + CR with incomplete hematologic recovery [CRi]) of this induction regimen. Secondary endpoints were MRD negativity (&amp;lt;1x10 -4 by flow cytometry), event-free survival (EFS), overall survival (OS) and safety. Bone marrow evaluation and one intrathecal injection chemotherapy were performed on day 22±2. Patients not achieving ORR continued blinatumomab for another 2 weeks (28 ug/day from day 1-14), followed by bone marrow re-evaluation. Consolidation therapy was given after achieving ORR with recommended multidrug combination chemotherapy (including high-dose methotrexate or cytarabine combined with asparaginase) or alternating with blinatumomab (28 ug/day for 28 days). If allogeneic hematopoietic stem cell transplantation (allo-HSCT) is not performed, consolidation therapy needs at least 4 courses before 2 years of maintenance therapy. Results: Interim results are presented here.By July 6, 2023 (data cut-off), 25 patients were enrolled with a median age of 42 years (range: 15-53); 68% were females. The Eastern Cooperative Oncology Group Performance Status score ranged from 0-1. Eight (32.0%) patients had poor cytogenetic risk factors, including 3 with P2RY8::CRLF2, 2 with hypodiploidy, 2 with KMT2A rearranged and 1 with alterations of IKZF1 (Table 1). The bone marrow evaluation done in 19 patients on day 8 prior to blinatumomab treatment showed that none of the patients had got ORR. All 21 (100%) patients evaluable for the primary endpoint attained CR/Cri - 19 at the end of 2 weeks of blinatumomab and the remaining 2 after another 2 weeks of blinatumomab (Table 2). The MRD negativity rate was 90.5% (19/21) after 2 weeks of blinatumomab which increased to 95.5% (20/21) after another 2 weeks of treatment with blinatumomab. In 21 patients evaluated for safety, blinatumomab-related cytokine release syndrome was reported in 10 (47.6%) patients (grade 1: n=6, grade 2: n=3 and grade 3: n=1). No incidence of neurotoxicity was reported. Febrile neutropenia was reported in 4 (19%) patients (all ≥grade 3). The non-hematological AEs reported were fever in 7 (33.3%) patients (any grade), increased ALT in 10 (47.6%) patients (any grade) and infections in 4 (19%) patients, including pneumonia in 2 and sepsis in 2 (all ≥grade 3). The median duration of neutrophil deficiency (&amp;lt;0.5×10 9/L) and platelet deficiency (&amp;lt;20×10 9/L) during induction therapy was 9 days (range: 0-20) and 1 day (range: 0-18), respectively. The median follow-up time was 4 months and no relapse or leukemia-related deaths were observed. The median EFS and OS were not yet reached. All enrolled patients are alive except one who died of infection after multidrug combination consolidation chemotherapy. The median cycles for consolidation were 2 (range: 1-5) with 3 patients undergoing allo-HSCT. Conclusion: Thesepreliminary results indicate that the reduced intensity chemotherapy followed by blinatumomab is an effective regimen in adults with newly diagnosed Ph-negative BCP-ALL, resulting in favorable response rates, deep remission, and low-grade treatment-related AEs. These promising findings may provide a rationale for integrating blinatumomab into future induction therapy recommendations.

Mutational Burden in High Risk Genes Do Not Affect Remission Rates and MRD Clearance in Elderly AML Patients Receiving CPX-351 Induction

Background: CPX-351 has recently been approved for the treatment of patients diagnosed with Acute Myeloid Leukemia (AML) arising from a previous myelodisplastic syndrome (s-AML) or secondary to chemotherapy (t-AML) as per former WHO 2016 classification. Minimal residual disease (MRD) assessment is a strong prognostic factor for relapse and shorter survival in AML patients undergoing intensive induction chemotherapy. Recent studies explored the role of genomic profile of AML influencing clinical outcome. In particular, Papaemmanuil et al showed that mutations in critical genes such as TP53, ASXL1, SRSF2 and RUNX1 are independently associated with a worse prognosis; moreover, co-occurrence of different high-risk mutations are predictors of dismal outcome when conventional chemotherapy is administered. Adverse risk mutations are particularly frequent in s-AML and t-AML. As clinical trials evaluating the prognostic relevance of MRD in the context of different molecular subsets mainly involve younger patients affected by de novo AML and receiving conventional 3+7 chemotherapy, there is a lack of data to define the impact of specific mutations on MRD clearance and prognosis in elderly s- AML and t-AML patients receiving CPX-351 induction. Aims: The aim of this study was to evaluate the prognostic impact of recurrent genic mutations and mutational burden at diagnosis on CR probability, MRD clearance and prognosis in a cohort of elderly s-AML or t-AML patients treated with CPX-351 induction chemotherapy. Methods: The study included 67 elderly patients (&amp;gt;60 year, median age 69, range 60-77) with a diagnosis of s-AML or t-AML according to WHO2016 classification, treated in our Center with CPX-351. Next generation sequencing (NGS) was performed using the Myeloid Solution panel by SOPHiA Genetics, encompassing 34 critical genes mutations. Sample have been processed on a Illumina MiSeq platform and the analysis performed with SOPHiA DDM® Software. MRD was analysed in all patients achieving complete remission (CR) with multicolour flow-cytometry, with a threshold of 0.1%. Results: AML patients were re-classified according to ELN 2022 risk score which was adverse, intermediate and favourable in 35, 29 and 3 patients, respectively. Median number of mutations for single patient (mutational burden) by NGS was 4 (range 2-9). Most frequent mutations involved: RUNX1 (44%), ASXL1 (37%), TP53 (33%), IDH1 (18%), IDH2 (14%), DNMT3A (14%), TET2 (8%). Four patients died before response assessment, mainly due to infections. Fifty-four patients (81%) achieved complete remission (CR) after first induction cycle; MRD evaluation was negative in 28/54 responding patients (52%). Univariate and multivariate analysis showed that factors traditionally associated with poor outcome such as ELN risk group, leukocytosis at diagnosis or previous treatment with hypomethylating agents did not affect the probability of CR rate and MRD negativity. Interestingly, having any high risk mutation, the combination of ≥2 high risk mutations or high mutational burden (having ≥ 4) did not affect CR probability and MRD negativity rate both in univariate and multivariate analysis. After cycle 2, the cumulative CR rate was 56/67 (84%), with 33/56 (59%) responding patients obtaining MFC MRD negativity. After a median follow up of 36 months (CI 95%; 22.4 -48.5 months), median OS was 19 months (CI 95% 13-24), whereas 2 year OS was 24%. Multivariate OS analysis revealed that negative MRD was the strongest independent predictor of longer survival (p&amp;lt;0.05). Notably, OS was not affected by mutational burden (29.2% and 27.6% for patients with less or more than 4 mutations, respectively, p=n.s, Fig.1). In landmark analysis, patients achieving CR and proceeding to allogeneic stem cell transplantation consolidation (HSCT) within 3 months from CR (N=13) had a significantly better outcome if compared to CR patients who did not receive HSCT or proceeded to transplant later (N= 41, 2-year OS: 84.6% and 31.7, respectively, p&amp;lt;0.03, Fig. 2). Conclusion : CPX-351 is able to induce good quality remission with high CR rate and MRD negativity, regardless of mutational burden, allowing a high number of elderly AML patients to undergo to HSCT. MRD evaluation has proven to be a strong prognostic tool also in the setting of elderly s-AML and t-AML patients receiving CPX-351. The prognostic value of high risk mutation seems to be less relevant in CPX-351 treated patients.

Venetoclax Combined with Homoharringtonine,Cytarabine and Aclacinomycin (HAAV) As Induction Therapy in Newly Diagnosed Young Adult Acute Myeloid Leukemia

Background: The remission rate of acute myeloid leukemia (AML) patients using traditional induction chemotherapy is approximately 60-70%. Venetoclax (Ven), a b-cell lymphoma 2 (BCL-2) inhibitor, in combination with chemotherapy or hypomethylating agents, has shown a significant increase in remission rates and improvement in patient survival for elderly or unfit for intensive chemotherapy newly diagnosed AML patients. The HAA regimen (consisting of Homoharringtonine, Cytarabine and Aclacinomycin), a specific traditional induction therapy for acute myeloid leukemia in China. The HAA regimen achieved complete remission rates about 70% as an induction regimen for newly diagnosed AML. Whether the combination of Ven with HAA regimen as an induction treatment can further enhance the complete remission rate in newly diagnosed adult AML patients requires investigation through well-designed clinical trials. Objective: To evaluate the efficacy and safety of HAA combined with Ven as induction regimen (HAAV) in young adult patients with newly diagnosed AML. Design, setting and participants: Single-arm, prospective clinical trial conducted at 8 hospitals in China. Eligible patients (16-60 years old) with newly diagnosed AML (exclude acute promyelocytic leukemia) were enrolled. The trial was registered on ClinicalTrials.gov (NCT05893472) and continues to accrue patients. Induction regimen: The induction regimen consisted of Homoharringtonine (2.5mg/㎡/d，d3-7 ), cytarabine (100mg/㎡/d by continuous intravenous infusion daily on d3-7) and Aclacinomycin (20mg/d, d3-7) combined with venetoclax (100mg d1, 200mg d2, 400mg d3-8). Main outcomes and measures: The primary endpoint was the overall response rate (ORR) after once cycle of HAAV regimen, which included complete remission (CR), complete remission with incomplete count recovery (CRi), morphologic leukemia-free state (MLFS) and partial remission (PR). Secondary endpoints included minimal residual disease (MRD), overall survival (OS), event-free survival (EFS) and adverse events. Results: Untill June 30, 2023, 40 patients were enrolled. The median age is 43 years (range, 18-60), with 60% (24/40) was male. According to the European Leukemia Network prognostic group (2022), 14 (35.0%), 14 (35.0%), and 12 (30.0%) patients were considered to belong to the favorable, intermediate, and adverse groups, respectively. Further details of the patients' characteristics are provided in Table 1. The ORR (CR+PR) was 97.5% (39/40 patients) after one cycle of the induction regimen with the CR rate was 95.0% (38/40). According to the ELN prognostic group (2022), the CR was 100% in favorable-risk patients (14/14), 100% in intermediate-risk patients (14/14), and 83.3% in adverse-risk patients (10/12). For patients who achieved CR, MRD negative rate was 88.9% (32/36) by flow cytometry. During the induction treatment, all patients experienced ≥Grade 3 hematological toxicity, the remaining common adverse reactions were infections and fever. None of patients died during the induction therapy. In patients who achieved response, the median time to recovery of the white blood count (WBC) to ≥1.0 × 10 9/L and the platelet count to ≥20 × 10 9/L after induction therapy was 13 (range: 10-52) and 13 days (range: 2-33), respectively. ( Table 1) Conclusions: Ven combined with HAA (HAAV) is a highly effective and safe induction therapy for young adult patients with de novo AML. To the best of our knowledge, this is the first report about Ven combined with HAA.

Phase 2 Study of CPX-351 in Combination with Venetoclax in Patients with Newly Diagnosed, High Risk Acute Myeloid Leukemia

Background CPX-351 is a nanoscale liposome of a fixed 5:1 molar ratio of cytarabine and daunorubicin which has improved survival of secondary acute myeloid leukemia (AML) 1. Venetoclax (ven) is a BCL2 inhibitor which, in combination with azacitidine or cytarabine, has become the standard of care for elderly AML. Ven has shown synergism with chemotherapy, with high complete remission (CR) rates in newly diagnosed (ND) and relapsed / refractory (RR) AML 2. In this study, we aim to assess the efficacy and safety of CPX-351 and ven (CPX-ven) in RR and ND AML. Methods This was a phase 2 study with a lead-in safety phase. Enrolment was allowed if the blasts were ≥10%. Patients (pts) age ≥18 with RR AML were eligible for the safety lead-in phase (LIP) or arm A. Arm B enrolled pts age 18 - 69 with ND AML. Other inclusion criteria included adequate liver, renal and cardiac function, and ECOG performance status ≤2. Pts with CNS involvement or prior CPX-351 were excluded. The recommend phase 2 dose was CPX-351 (daunorubicin 44 mg/m 2 and cytarabine 100 mg/m 2 IV on D1, 3 and 5 of induction, and daunorubicin 22 mg/m2 IV on D1 and 3 during consolidation) combined with ven on D2-8 of each cycle. Ven was dosed at 300mg daily and reduced to 150mg or 50mg daily for pts on a moderate or strong CYP3A inhibitors, respectively. The primary outcome measure was complete remission (CR) or CR with incomplete count recovery (CRi). Here, we report the outcomes of arm B including pts with ND AML. Results 14 pts were enrolled on arm B. One pt withdrew and one was too early in treatment, therefore 12 were evaluable. Baseline characteristics are shown in Table 1. The median age was 59.5 years (range, 44 - 69); Four (33.3%) were female. All 12 (100%) pts were classified as adverse risk per the 2017 European Leukemia Net Guidelines. Two (16.7%) pts had treatment for a prior non-myeloid malignancy (therapy-related AML). Eight (66.7%) had an antecedent haematological disorder (secondary AML), of whom seven had treatment (median 1 line, range 1 - 2). Four (33.3%) pts had a complex karyotype, of whom three harbored a TP53 mutation. Nine (75.0%) pts achieved a response, including four CR (33.3%), five CRi (41.6%), and one induction mortality (8.3%) prior to disease assessment. 3/4 (75.0%) pts with complex cytogenetics (including 2/3 (66.7%) with a TP53 mutation) achieved a CR/CRi. Of the secondary AML pts with an evaluable response, 5/7 (71.4%) achieved a CR/CRi. Of the nine pts achieving CR/CRi, five (55.5%) were negative for minimal residual disease (MRD) by flow cytometry. The median number of cycles to CR/CRi was one (range 1 - 2). The median overall survival (OS) was 12.9 months (95% CI, 3.1 - not reached, NR, Figure 1). The median relapse-free survival (RFS) was 8.7 months (95% CI, 3.1 -NR). 7/9 (77.8%) of responding pts underwent an allogeneic stem cell transplant (SCT) after attaining CR/CRi. There were 90 adverse events (AE) in 10 (83.3%) pts. 80 (88.9%) were grade 1 or 2, 10 (11.1%) were grade ≥3. The most common AE was gastrointestinal with seven (7.8%) occurrences. Four (33.3%) pts developed grade ≥3 infections; of these, one (8.3%) died. The cause of death was neutropenic septic shock due to pneumonia. Conclusion CPX-ven is a feasible option for remission induction in pts with high-risk, newly diagnosed AML. The combination produced high rates of response and MRD negativity in a cohort of pts with adverse risk features, including pts with adverse karyotype and AML following prior HMA-based treatment, allowing them to proceed with SCT. Toxicities are as expected for an intensive chemotherapy regimen. Further studies are needed to confirm the efficacy of this combination.

Pharmacodynamic Biomarkers and CtDNA Support the Mechanism of Action and Clinical Efficacy of Golcadomide (CC-99282) Combined with R-CHOP in Previously Untreated Aggressive B-Cell Lymphoma

Introduction Golcadomide (GOLCA, CC-99282) is an orally available cereblon E3 ligase modulator (CELMoD ®) that potently degrades target proteins Ikaros and Aiolos, enhancing antiproliferative, apoptotic, and immunomodulatory activity and preferentially distributing to lymphoid organs. In a phase 1 study, GOLCA monotherapy previously demonstrated a manageable safety profile with promising clinical activity in relapsed/refractory non-Hodgkin lymphoma (Michot Blood 2021). In the ongoing CC-220-DLBCL-001 study (NCT04884035), GOLCA dose finding is underway in patients with previously untreated aggressive B-cell lymphoma (BCL), in combination with R-CHOP in 21-day (D) cycles (C), at a variety of GOLCA dose levels (DLs) and schedules: DL-1 = 0.2 mg D1-7, DL1 = 0.4 mg D1-7, and DL2 = 0.4 mg D1-10. Here, we report Ikaros degradation, immune modulation, circulating tumor DNA (ctDNA) assessment, and baseline tumor genomics. Methods Peripheral blood was collected to analyze Ikaros and Aiolos levels in T cells by flow cytometry (C1D1, C1D7, and C2D1). Immune phenotyping of T and natural killer (NK) cells was performed by flow cytometry (C1D1, C1D15, C2D1, and C3D1). ctDNA levels were analyzed by the PhasED-Seq assay (timepoints C1D1, C2D1, C3D1, and end of treatment [EOT]; Kurtz Nat Biotechnol 2021); somatic variants were filtered by performing PhasED-seq on buffy coats. Pretreatment biopsies were analyzed by whole genome sequencing and whole transcriptome sequencing. DL1 (0.4 mg D1-7) and DL2 (0.4 mg D1-10) data were pooled. Results Ikaros levels in T cells at 5 hours after the first dose had a 1.1% median increase with 0.2 mg and 44% median decrease with 0.4 mg; by C1D7 pretreatment, Ikaros substantially decreased with both DLs (median: 0.2 mg, 87% decrease; 0.4 mg, 83% decrease). Ikaros differences between 0.2 mg and 0.4 mg were not substantial. By C2D1, Ikaros levels recovered to baseline. Based on preclinical benchmarks, steady-state Ikaros degradation in T cells suggested that direct tumor cell killing by GOLCA was achieved. Changes in T and NK cell phenotypes in peripheral blood included activation, increased proliferation, increased T effector memory and regulatory cell levels, and decrease in naive T cells. Changes were seen by C1D15 and maintained at C2D1 and C3D1. Overall, immune changes between 0.2 mg and 0.4 mg dose levels were not substantially different. Phased variant data from ctDNA and buffy coats were evaluable for 34 patients (0.2 mg, n =15; 0.4 mg, n = 19). Baseline ctDNA levels were similar between the 0.2 mg and 0.4 mg cohorts and, consistent with prior studies, correlated with International Prognostic Index and cell of origin. Previously reported landmarks such as early molecular response (EMR; ≥ 2 log decrease) at C2D1 and major molecular response (MMR; ≥ 2.5 log decrease) at C3D1 were assessed (Kurtz J Clin Oncol 2018) . A high fraction of patients designated high risk by pretreatment ctDNA (≥ 2.5 log haploid genome equivalents [HGE]/mL; Kurtz J Clin Oncol 2018) were clinical responders. Patients who achieved minimal residual disease (MRD) negativity on treatment generally remained MRD negative at subsequent timepoints. At C2D1, the EMR and MRD negativity rates for 0.2 mg were 73% (11/15) and 20% (3/15), respectively; for 0.4 mg these rates were 83% (15/18) and 44% (8/18). At C3D1, the MMR and MRD negativity rates for 0.2 mg were 83% (10/12) and 42% (5/12), respectively; for 0.4 mg these were 83% (10/12) and 58% (7/12). Although ctDNA differences between 0.2 mg and 0.4 mg were not substantial, numerically greater ctDNA changes were seen with 0.4 mg GOLCA + R-CHOP vs 0.2 mg GOLCA + R-CHOP and vs R-CHOP and R-CHOP-like regimens from other cohorts ( Figure). Insufficient samples were available to draw conclusions about EOT, but additional ctDNA data will be presented. Whole genome and transcriptome sequencing data from GOLCA + R-CHOP-treated patients will be shown. Conclusions Pharmacodynamic biomarkers and ctDNA levels indicate that both tumor-intrinsic and immune-modulating mechanisms of action of GOLCA remain relevant in combination with R-CHOP in previously untreated aggressive BCL. ctDNA data during treatment are consistent with the efficacy noted on clinical restaging. Translational data demonstrate the potency of GOLCA and will support future frontline clinical trial designs in patients with untreated aggressive BCL. Study support: Celgene, a Bristol-Myers Squibb Company

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.