Minimal Residual Disease Negativity Research Articles

Abstract B032: Genome-wide 5-hydroxymethylation mapping in cell-free DNA to characterize the epigenetic differences in minimal residual disease of multiple myeloma

Abstract Background: Multiple myeloma (MM), a B-cell neoplasm characterized by the infiltration of malignant plasma cells into the bone marrow, is the second most common blood malignancy in the United States. The molecular pathogenesis of MM involves both genetic and epigenetic alterations. While 60-75% of newly diagnosed patients achieve a complete response or better with current modern combination therapies, almost all patients eventually progress largely due to the persistence or re-emergence of minimal residual disease (MRD). Monitoring for MRD has become essential for evaluating treatment efficacy and predicting long-term outcomes in MM patients. We aimed to investigate whether epigenetic changes, particularly 5- hydroxymethylcytosines (5hmC), at diagnosis are associated with MRD status following treatment. Methods: Utilizing 5hmC-Seal, a highly sensitive chemical labeling technique, we profiled genome-wide 5hmC in circulating cell-free DNA (cfDNA) and bone marrow genomic DNA (gDNA) at baseline and after 8 cycles of treatment (C8) from newly diagnosed MM patients (n=25) enrolled in a clinical trial (NCT01816971). MRD testing was performed on bone marrow samples using the clonoSEQ next generation sequencing assay (limit of detection 10-6). Results: The 5hmC modification levels were summarized across various genomic features, revealing enrichment in gene bodies and enhancer regions, consistent with the known regulatory role of 5hmC. We ranked 5hmC-modified genes at baseline by their variability, and found that the number of overlapping genes between cfDNA and gDNA was significantly higher than expected by permutation analysis. Subsequently, we identified the top 100 most variable 5hmC- modified genes in gDNA, which exhibited a higher Pearson correlation with cfDNA within individuals (mean r=0.90) compared to between individuals (mean r=0.82; p<0.05), suggesting that cfDNA has the potential to reflect gDNA in capturing some MM-related variations. Among the 11 patients with MRD+ at C8, a genome-wide scan of 5hmC in cfDNA comparing baseline and C8 identified 1,614 differentially modified genes (p<0.05) after adjusting for age and sex. [BC1] Furthermore, we identified 459 differentially modified genes comparing baseline 5hmC levels between patients who were MRD+ (n=11) and MRD- (n= 14) at C8 (p<0.05), after adjusting for age and sex. These results highlight the differential epigenetic landscape associated with MRD status. Conclusions: Genome-wide 5hmC profiling of cfDNA from blood revealed a similar epigenetic landscape to gDNA from bone marrow in patients with MM, suggesting that cfDNA may offer a less invasive alternative for assessing epigenetic modifications. Moreover, this profiling identified distinct epigenetic changes associated with the achievement of MRD- negativity. These findings provide a foundation for further investigation into the molecular alterations linked to MM disease biology that could potentially lead to MRD negativity. Future directions will focus on identifying biomarkers that could inform personalized treatment strategies. Citation Format: Zhou Zhang, Bei Wang, Krissana Kowitwanich, John Cursio, Daniel Appelbaum, Chuan He, Wei Zhang, Benjamin Derman, Brian Chiu, Andrzej Jakubowiak. Genome-wide 5-hydroxymethylation mapping in cell-free DNA to characterize the epigenetic differences in minimal residual disease of multiple myeloma [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr B032.

Abstract B006: Qualitative research study on the use of minimal residual disease as an intermediate endpoint in multiple myeloma clinical trials in Saudi Arabia

Abstract Introduction: The U.S. Food and Drug Administration has recently considered minimal residual disease (MRD) as an acceptable accelerated approval endpoint in multiple myeloma (MM). Meta-analysis studies have shown the clinical benefit of MRD negativity in certain hematological cancers such as MM. Objectives: This qualitative research study, with a unique focus on the Saudi context, aims to assess the opinions and experiences of hematology and oncology specialists and consultants in Saudi Arabia. The study is particularly interested in their views on the use of MRD as an intermediate endpoint in early-phase clinical trials for fast-track drug approval by the Saudi Food and Drug Authority in the context of multiple myeloma. This includes assessing the use of MRD in both newly diagnosed and relapsed/refractory MM. The secondary objective is to gather information about the feasibility and availability of sensitive MRD detection methods in real-world medical practice and clinical trials in Saudi Arabia. Study Design: The study will involve interviewing 30 registered male or female physicians specialized in hematology and oncology in Saudi Arabia. The physicians will be included in the study using purposive sampling methods. The study will collect the physicians’ opinions and experiences about MRD. The interviews will be conducted through a single focus group and several face-to- face interviews or performed online, using ZOOM. Participants should have more than one year of experience post-residency or post-fellowship training. The predetermined set of semi- structured questions will cover topics such as the definition of MRD, its clinical and research significance, MRD detection thresholds, duration of MRD negativity, and its correlation with other clinical endpoints, such as progression-free survival and overall survival. The interviews will be conducted by scientific oncology and hematology evaluation experts at the Saudi Food and Drug Authority, who play a crucial role in this study. The study will consist of 5–10 semi- structured one-to-one interviews and focused group discussions of as few as four participants. Before starting any interview, participants will complete consent forms, including the study’s goals and who will conduct the study. Qualitative data will be prepared and analyzed by an expert in data analysis, ensuring the highest research standards. The results will be presented using descriptive and interpretive methods. Citation Format: Albandari A Alnasser, Tariq H Alqurayshah. Qualitative research study on the use of minimal residual disease as an intermediate endpoint in multiple myeloma clinical trials in Saudi Arabia [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr B006.

Abstract B007: A qualitative research study on hematology and oncology consultants’ experiences and opinions on using minimal residual disease (MRD) as a fast-track approval endpoint in early-phase clinical trials in multiple myeloma in Saudi Arabia

Abstract Introduction: The U.S. Food and Drug Administration recently considered the minimal residual disease (MRD) as an acceptable accelerated approval endpoint in multiple myeloma (MM). The data from the meta-analysis studies established the clinical benefit of MRD negativity in certain hematological cancers such as MM. Objectives: The primary objective of this qualitative research study is to assess hematology and oncology consultants’ opinions and experiences on the adequacy of using minimal residual disease (MRD) as an intermediate endpoint in early- phase clinical trials in multiple myeloma (MM) for fast-track approval of drugs and biological products in the Saudi Food and Drug Authority. That may include using MRD in MM in both settings: newly diagnosed and relapsed/refractory MM. The secondary objective is to gather information about the feasibility and availability of sensitive methods for detecting MRD in the context of real-world medical practice and clinical trials in Saudi Arabia. Study Design: The study design is a qualitative approach to interviewing 30 registered male, or female physicians specialized in hematology and oncology in Saudi Arabia. The interviews will be conducted in two ways: a single focus group and several face-to-face interviews. The participants should have more than 1 year of experience post-fellowship training. The participants will be invited for an interview via email or phone. A predetermined set of semi-structured questions is to be asked in the same order to each participant. The topic of questions will include the definition of MRD, clinical and research significance of MRD, MRD detection thresholds (e.g., 10^-5 vs. 10^-6), duration of MRD negativity at the complete response, correlation with other clinical endpoints such as progression-free survival (PFS) and overall survival (OS). The interviews will be conducted by scientific oncology and hematology evaluation experts at the Saudi Food and Drug Authority who have considerable experience in engaging in personal discussion. This qualitative study has about 5–10 semi-structured one-to-one interviews of hematology and oncology consultants performed at a convenient time for each doctor. Moreover, the discussions in focus groups can be as small as four participants. Qualitative data will be prepared and analyzed by an expert in data analysis. Citation Format: Tariq Hassan Alqurayshah, Albandari Alnasser, Tariq Alqurayshah. A qualitative research study on hematology and oncology consultants’ experiences and opinions on using minimal residual disease (MRD) as a fast-track approval endpoint in early-phase clinical trials in multiple myeloma in Saudi Arabia [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr B007.

Equecabtagene Autoleucel in Patients With Relapsed or Refractory Multiple Myeloma

Equecabtagene autoleucel (eque-cel), a fully human-derived B-cell maturation antigen-targeting chimeric antigen receptor (CAR) T-cell therapy, has exhibited potential for the treatment of relapsed or refractory multiple myeloma (RRMM), and further investigation in a larger cohort is necessary. To evaluate whether eque-cel can benefit patients with RRMM and determine the overall response rate postinfusion. The FUMANBA-1 trial was a single-arm, open-label, phase 1b/2 trial that evaluated eque-cel in adult patients with RRMM. Enrollment began in April 2020, and patients who received eque-cel will be monitored for a minimum of 15 years following the infusion. As of September 2022, patients with heavily pretreated RRMM who received at least 3 prior courses of therapy from 14 centers were enrolled. Data were analyzed from April 2020 to September 2022. Patients received a single infusion of eque-cel at 1.0 × 106 CAR-positive T cells/kg after the lymphodepletion. Efficacy was the primary objective, and safety, pharmacokinetics, and pharmacodynamics were secondary objectives. Of 103 patients who received an eque-cel infusion, 55 (53.4%) were male, and the median (range) age was 58 (39-70) years. A total of 101 patients were evaluable for efficacy. At a median (range) follow-up of 13.8 (0.4-27.2) months, the overall response rate was 96.0% (97 of 101), with 74.3% (75 of 103) achieving a complete response or better. Among the 12 patients who had prior CAR T-cell treatment, 75% (9 of 12) achieved a response. The median progression-free survival was not reached, with a 12-month progression-free survival rate of 78.8% (95% CI, 68.6-86.0). A total of 96 patients (95.0%) achieved minimal residual disease negativity at a sensitivity threshold of 10-5. Adverse events were favorable: 96 of 103 patients (93.2%) experienced cytokine release syndrome (grade 1 to 2 in 95 patients [92.3%]) and 2 (1.9%) experienced immune effector cell-associated neurotoxicity syndrome (grade 1 to 2). All cases of immune effector cell-associated neurotoxicity syndrome and 94 of 96 cases of cytokine release syndrome resolved with treatment. Additionally, only 20 patients (19.4%) developed antidrug antibodies. Cellular kinetic analysis confirmed CAR-positive T cells in all patients, with the longest duration at 735 days. In this trial, eque-cel led to early, deep, and durable responses in patients with heavily pretreated RRMM with a manageable safety profile. Patients with prior CAR T-cell therapy also benefitted from eque-cel. Chinese Clinical Trial Registry Identifier: ChiCTR2000033946.

Venetoclax in combination with a pediatric-inspired regimen for the treatment of newly diagnosed adults with Philadelphia chromosome-negative acute lymphoblastic leukemia.

BCL-2 protein overexpression, common in B-cell acute lymphoblastic leukemia (B-ALL), including the Philadelphia (Ph)-like subtype, mediates leukemic cell survival. We treated 24 patients with 14 days of BCL-2 inhibitor, venetoclax, 400 mg daily (dose level 1) during induction and consolidation cycles combined with the CALGB 10403 regimen in newly diagnosed adults with Ph-negative B-ALL. Median age was 31 (range: 18-53) years, 92% were Hispanic, and 12 (50%) patients had Ph-like ALL. No dose limiting toxicity occurred in the phase 1 part. Median times to neutrophil and platelet count recovery were 20 and 21 days from start of induction, respectively. The most common grade ≥3 treatment-related adverse events were leukopenia (96%), neutropenia (83%), anemia (83%), thrombocytopenia (79%), lymphopenia (71%), hyperbilirubinemia (38%), and elevated ALT (33%). One patient with non-Ph-like ALL died from asparaginase-associated pancreatitis, and 23 (96%) patients achieved complete remission (CR) or CR with incomplete count recovery (CRi) following induction with or without extended induction phase. Of 22 patients who started consolidation, 20 (91%) achieved negative minimal residual disease status (MRD-) (.

Delaying pegaspargase during induction in adults with acute lymphoblastic leukaemia is associated with lower risk of high-grade hepatotoxicity without adversely impacting outcomes.

Pegaspargase is a key drug for the treatment of younger adults with acute lymphoblastic leukaemia (ALL). Pegaspargase-associated hepatotoxicity is most common during induction, and its incidence increases with age and body mass index (BMI). We hypothesized that the delayed administration of pegaspargase during induction is associated with lower risk of hepatotoxicity while retaining efficacy. We retrospectively reviewed 141 adult patients with newly diagnosed ALL who received pegaspargase during induction from November 2013 to February 2024. There were 78 (55.3%) patients who received early pegaspargase (EP) on day 4 and 63 (44.7%) patients who received delayed pegaspargase (DP) on day 15. High-grade hepatotoxicity (grade ≥ 3 transaminitis and/or hyperbilirubinaemia) occurred more frequently in the EP group (p = 0.06). Rates of complete remission and negative minimal residual disease post induction were not different between cohorts. Univariate logistic regression analysis showed that BMI and age significantly predicted an increased risk of high-grade hepatotoxicity while DP was associated with a lower risk (odds ratio = 0.44; p = 0.04). Overall survival and event-free survival were not significantly different between cohorts. Delaying pegaspargase administration from day 4 to day 15 during induction cycle in adults with ALL might reduce the risk of high-grade hepatotoxicity without adversely impacting clinical efficacy outcomes.

Early minimal residual disease eradication in light chain amyloidosis generates deeper and faster cardiac response

Minimal residual disease (MRD) is of growing interest in light chain (AL) amyloidosis and is associated with higher rates of cardiac response. A new graded cardiac response criteria has been proposed for better assessment of cardiac improvement. We evaluated MRD status in 63 patients with cardiac AL amyloidosis using next generation flow cytometry (sensitivity ≥ 1*10–5) within four cycles after treatment initiation and cardiac response kinetics. All patients were treated with first-line proteasome inhibitor (100%) and predominantly bortezomib (87.3%). The overall early MRD negative rates were 33.3%. Patients who achieved early MRD negativity were less likely to harbor t(11;14) (21.1% vs 57.5%, P = 0.009). The MRD negative rates amongst patients in hematologic complete response were 66.7% (14/21), and in very good partial response 29.2% (7/24). Early MRD negativity was associated with a higher likelihood of achieving ≥ cardiac partial response (≥ CarPR) (66.7% vs 38.1%, P = 0.032) and ≥ cardiac very good partial response (≥ CarVGPR) (38.1% vs 11.9%, P = 0.023) throughout first-line therapy. The cumulative incidence curve of achieving ≥ CarPR (P = 0.034) and ≥ CarVGPR (P = 0.026) showed significant difference between early MRD negative and positive group. After a median follow-up time of 27.2 months, the median progression free survival was longer in early MRD negative group (not reached vs 31.3 months, P = 0.033). Early MRD eradication in cardiac AL amyloidosis generated deeper and faster cardiac organ response.

Long-Term Safety and Efficacy of the Fully Human CAR-T Therapy CT103A in Relapsed/Refractory Multiple Myeloma

CT103A is a fully human chimeric antigen receptor T-cell (CAR-T) product for targeting B-cell maturation antigen (BCMA). This study presents the updated safety and efficacy profiles of CT103A in patients with relapsed/refractory multiple myeloma (RRMM) after long-term follow-up. As of July 31, 2023, the median follow-up time after CAR-T-cell infusion was 45.0 months (range, 0.7-58.3 months). During long-term follow-up, the incidence of adverse events gradually decreased over time. One patient had a maximum duration of response of nearly five years. All 18 patients (100%) achieved partial remission or better; 77.8% (14 of 18) of patients eventually exhibited complete response (CR) or stringent complete response (sCR), with response increasing over time. At the time of data cut-off, nine patients were still alive, and seven patients had an sCR status with negative minimal residual disease (MRD). The median progression-free survival (PFS) was 22.6 months, and the median overall survival (OS) was 50.2 months for all 18 patients. The median CAR transgene persistence was 14.0 months (range, 0.7-57.3 months). Long-term follow-up demonstrated that CT103A confers durable clinical benefit for RRMM patients based on the sustained presence of fully human CAR-T cells.

Philadelphia chromosome-positive or Philadelphia chromosome-like B-cell precursor acute lymphoblastic leukemia with multilineage involvement in pediatric patients: a report of two cases and literature review.

Based on driver mutations and gene expression profiles, the International Consensus Classification currently divided the entity 'Philadelphia chromosome-positive (Ph+) B-cell precursor acute lymphoblastic leukemia (ALL)' into two subtypes: lymphoid-only and multilineage involvement (Ph+ ALL-L and -M, respectively). The similar biological characteristics of Ph-like ALL and Ph+ ALL drove us to assume that Ph-like ALL-M subtypes exist. This report presents two pediatric ALL cases (one Ph+ and one Ph-like) with minimal residual disease negativity established by multicolor flow cytometry but persistent transcript detection by quantitative PCR (qPCR) even after second-line treatment with tyrosine kinase inhibitors combined with blinatumomab immunotherapy. Using droplet digital PCR, BCR::ABL1 or TPM3::PDGFRB transcripts were identified in CD19+ cells as well as in non-CD19+ cells, suggesting the presence of a Ph+ or Ph-like ALL-M subtype originating from hematopoietic stem cells. This report provides information for better characterization, diagnosis, and treatment of these ALL subtypes.

Long-term real-world evidence of CPX-351 of high-risk AML patients identified high rate of negative MRD and prolonged OS

CPX-351 has been approved for patients with therapy-related acute myeloid leukemia (t-AML) or AML with myelodysplasia-related changes (MRC-AML). No extensive data are available on MRD and long-term clinical outcome using CPX-351 in AML in real-life. We retrospectively collected data from 168 patients in 36 centers in France and Italy who had received one or two cycles of induction with CPX-351. All patients were older than 18 years and had newly diagnosed, untreated t-AML or MRC-AML. With a median follow-up of 3 years, median OS was 13.3 months. Median OS was 20.4 months vs. 12.9 months for patients with MRD below or above 10-3, respectively (p=0.006). In a multivariate analysis, only MRD >10-3 was associated with a poorer OS (hazard ratio [HR]=2.6, 95% CI 1.2-5.5, p=0.013). We also observed a trend towards a better median OS in patients who underwent HSCT with MRD <10-3 (not reached vs. 26.0 months, p=0.06). Achievement of MRD negativity contributed to the improvement of OS in the overall population and, maybe, in transplanted patients. These data provide the rationale for the two ongoing studies evaluating CPX-351 vs. 7+3 in non-MRC-AML and non-t-AML using MRD as the primary endpoint for ALFA-2101 phase II clinical trial and event-free survival for AMLSG 30-18 phase III clinical trial. Funding: Any

Development of an 18-color flow cytometry panel for B-lymphoblastic leukemia minimal residual disease detection

Abstract B-cell acute lymphoblastic leukemia (B-ALL) is characterized by a neoplastic proliferation of precursor B cells that have blast cytomorphology and immature immunophenotype. Following treatment of B-ALL, flow cytometry is utilized to detect minimal residual disease (MRD), which aids in monitoring therapeutic response and informing prognosis. In our institution, the BD FACSCanto cytometer is used in conjunction with two standardized 8-antibody EuroFlow panels to detect MRD in B-ALL patients. The objective of this study was to validate a new 18-color B-ALL MRD panel for bone marrow aspirate specimens to be run on a BD LSRFortessa cytometer, with the intention of improving sensitivity and consolidating the testing into one antibody panel. The proposed panel consisted of 22 antibodies, some of which were stacked within the same fluorescence channel, in addition to a viability stain. Twelve bone marrow aspirate specimens collected in 2023 (five positive and seven negative B-ALL MRD specimens) were stained with the new antibody panel and analyzed on the Fortessa cytometer. CD45 dim, CD19-positive blasts were analyzed using BD FACSDiva Software. For the five specimens previously reported as B-ALL MRD-positive using the EuroFlow panels, we were able to detect phenotypically identical B-ALL cells with the 18-color panel. A paired t-test done on the five MRD-positive specimens showed no significant difference in the percentage of residual B-ALL cells (out of total viable cells) measured by the 18-color panel when compared to the EuroFlow panels (EuroFlow/18-color: 0.0096%/0.0097%, 0.024%/0.012%, 0.94%/0.99%, 0.85%/0.85%, 0.022%/0.017%; p=0.58). All seven specimens that were previously reported as B-ALL MRD-negative using the EuroFlow panels were also negative for residual B-ALL cells when stained with the 18-color panel and analyzed on the Fortessa cytometer. The antibody cost per test of the EuroFlow panels ($20-$25, ~$44 for both panels) and new 18-color panel ($63) were calculated based on the unit cost of each antibody aliquot and the required volume of reagent per test. In summary, the new 18-color B-ALL MRD panel run on the BD LSRFortessa cytometer appears to provide similar results as the EuroFlow panels run on the BD FACSCanto cytometer. Although compared to the two EuroFlow panels, the single 18-color panel is more expensive per test in terms of antibodies, it may be preferable when there is scant tissue (such as cerebrospinal fluid) as there may not be enough material to run both EuroFlow panels.

Real-World Evidence on Prognostic Value of MRD in Multiple Myeloma Using Flow Cytometry.

Minimal residual disease (MRD) is one of the most important prognostic factors in multiple myeloma (MM) and a valid surrogate for progression-free survival (PFS) and overall survival (OS). Recently, MRD negativity was approved as an early clinical endpoint for accelerated drug approval in MM. Nevertheless, there is limited evidence of MRD utility in real-world setting. In this retrospective multicenter study, we report outcomes of 331 newly diagnosed MM patients with MRD evaluation at Day+100 after autologous stem cell transplantation using flow cytometry with a median limit of detection of 0.001%. MRD negativity was reached in 47% of patients and was associated with significantly prolonged median PFS (49.2 months vs. 18.4 months; hazard ratios (HR) = 0.37; p < 0.001) and OS (not reached vs. 74.9 months; HR = 0.50; p = 0.007). Achieving MRD negativity was associated with PFS improvements regardless of age, International Staging System (ISS) stage, lactate dedydrogenase (LDH) level, or cytogenetic risk. Importantly, MRD positive patients benefited from lenalidomide maintenance versus no maintenance (18-months PFS: 81% vs. 46%; HR = 0.24; p = 0.002) while in MRD negative patients such benefit was not observed (p = 0.747). The outcomes of our real-world study recapitulate results from clinical trials including meta-analyses and support the idea that MRD positive patients profit more from lenalidomide maintenance than MRD negative ones.

Measurable residual disease monitoring in AML with FLT3-ITD treated with intensive chemotherapy plus midostaurin

AbstractMeasurable residual disease (MRD) monitoring in acute myeloid leukemia (AML) with an FLT3 internal tandem duplication (FLT3-ITDpos]) has been hampered by the broad heterogeneity of ITD mutations. Using our recently developed FLT3-ITD paired-end next-generation sequencing (NGS)–based MRD assay with a limit of detection of 10−4 to 10−5, we evaluated the prognostic impact of MRD at different time points in 157 patients with FLT3-ITDpos AML who were enrolled in the AMLSG16-10 trial and who were treated with a combination of intensive chemotherapy and midostaurin, followed by midostaurin maintenance. Achievement of MRD negativity (MRDneg) after 2 cycles of chemotherapy (Cy2), which was observed in 111 of 142 (78%) patients, was predictive of superior 4-year rates of cumulative incidence of relapse (CIR) (4y-CIR; 26% vs 46%; P = .001) and overall survival (OS) (4y-OS; 70% vs 44%; P = .012). This survival advantage was also seen among patients who underwent allogeneic hematopoietic-cell transplantation during first complete remission (4y-CIR, 14% vs 39%; P = .001; 4y-OS, 71% vs 49%; P = .029). Multivariate models for CIR and OS after Cy2 revealed FLT3-ITD MRDneg as the only consistent favorable variable for CIR (hazard ratio [HR], 0.29; P = .006) and OS (HR, 0.39; P = .018). An NPM1 co-mutation correlated with a deeper molecular response as reflected by stronger MRD reduction and a higher rate of FLT3-ITD MRDneg after Cy2. During follow-up, conversion from MRDneg to MRDpos was a strong, independent factor for inferior CIR (HR, 16.64; P < .001) and OS (HR, 4.05; P < .001). NGS-based FLT3-ITD MRD monitoring allows for the identification of patients at high risk for relapse and death following treatment with intensive chemotherapy and midostaurin. Using NGS-based technology, FLT3-ITD emerges as a novel, highly clinically relevant target for MRD monitoring. This trial was registered at www.ClinicalTrials.gov as #NCT01477606.

B-227 Customized molecular tests for minimal residual disease: a tool for therapeutic decisions in follicular lymphoma patients

Abstract Background Monitoring of minimal residual disease (MRD) is based on accurate laboratory tests which can recognize a small fraction of malignant cells that survived the course of treatment. Several studies of the B-non-Hodgkin lymphoma group have been presented that MRD positivity at the end of treatment is a negative prognostic index. Follicular lymphoma (FL) is a chronic indolent malignancy, which response highly to immuno-chemotherapy followed by prolonged remissions but with inevitable relapse in most patients. The GALLIUM study showed that immuno-chemotherapy combinations, 6 cycles of bendamustine-obinutuzumab (BO), is the most efficacious treatment, but with severe side effects .In addition, 90% of patients achieved negative MRD from peripheral blood (PB) or bone marrow (BM) after only 3 BO cycles. These findings raise the possibility for MRD based treatment approach, where the duration of chemotherapy could be decided according to MRD status at mid-induction (MI). Identification of a marker in the PB and/or BM of each FL patient which will be use to the design of a sensitive RQ-PCR test for MRD detection for follow-up. Methods Qualitative PCR for translocation 14:18 and for the VDJ rearrangement sequence of the immunoglobulin heavy chain was used for marker identification. MRD monitoring was done by RQ-PCR. MRD monitoring for VDJ was designed specifically to each patients based on his VDJ sequence. MRD was assessed on PB and BM at MI. Results Marker for monitoring was identified at 11/21 patients in this study. After 3 combined therapy cycles, 7 patients were found to have MRD negativity by RQ-PCR therefore continue with immuno-therapy only. MRD positivity was assessed in BM of 3 patients (0.11%, 0.022%, and 0.133%). These 3 patients continued with the combined therapy. RQ-PCR sensitivity was 10-4-10-5. Conclusions This study will reveal the ability to use sensitive and specific MRD that has to be designed for each patient according to his marker and enable the establishment of a treatment with a high safety profile for FL patients. Correlation between MRD status and clinical and safety parameters will be assessed at the end of the study, 30 months after the first treatment, taking into account MRD status from different time point of the follow-up period.

T(11;14) with multiple myeloma: Standard risk survival but slow and poor response.

We described 790 patients with newly diagnosed multiple myeloma, including 224 (28.4%) standard risk (SR) patients without t(11;14), 99 (12.5%) patients with t(11;14)alone, 58 (7.3%) with t(11;14) + HR, and 409 (51.8%) in the high-risk cytogenetic abnormality (HRCA) group including t(4;14), t(14;16), t(14;20), C1A1 and/or del(17p) but without t(11;14), to evaluate the impact of t(11;14) in NDMM patients on response rate, response kinetics and survival. Our study showed that NDMM patients in the t(11;14)alone group had similar PFS (49.3 vs. 50.7months; P = 0.392) and OS (112.4 vs. NR months; P = 0.982) as those in the SR group. However, the t(11;14)alone group exhibited a significantly poorer depth of response compared to the SR group, particularly with a lower MRD negativity rate (60.0% vs. 76.0%, P = 0.009). In the t(11;14)alone group, MRD status did not significantly impact PFS or OS, which was in contrast to the other groups. Response kinetics analyses showed that the t(11;14)alone group had a slower response rate than the other subgroups (t(11;14)alone vs. SR vs. HRCA: median time to MRD negativity = 9.19 vs. 4.25 vs. 4.27 months; P < 0.001). Our study showed that t(11;14)alone was characterized by survival comparable to standard risk cytogenetics despite exhibiting the slowest timing of response onset and lowest plateau of remission, which suggested a relatively indolent clinical course.

Clinical Outcome of Induction Treatment in the Era of Novel Agents and the Impact of the Number of High-Risk Cytogenetic Abnormalities (HRA) on Prognosis of Patients With Newly Diagnosed Multiple Myeloma (NDMM): Insights From a Multicenter Study.

In the era of novel agents, the clinical outcomes of induction treatment and the impact of the number of high-risk cytogenetic abnormalities (HRA) in newly diagnosed multiple myeloma (NDMM) need to be explored. Through this study, we aim to analyze the effectiveness of different induction treatments and explore the survival outcomes of patients with varying numbers of HRA. A total of 734 patients from seven medical centers were included in our study. Patients in the CD38 monoclonal antibody or IMiDs plus proteasome inhibitors (PI) groups had significantly superior overall survival (OS) and progression-free survival (PFS) compared to those receiving IMiDs or PI alone. Additionally, the CD38 monoclonal antibody conferred a PFS advantage over IMiDs plus PI. Patients with ≥ 2 high-risk cytogenetic abnormalities (HRA) exhibited an extremely poor prognosis and should be considered ultra-high-risk individuals in multiple myeloma (MM). The CD38 monoclonal antibody, transplantation, and achieving minimal residual disease (MRD) negativity only partly mitigated the poor prognosis in patients with HRA. Furthermore, patients with 1q21 gain/amplification (1q21+) only had a significantly worse prognosis compared to patients without HRA, and those with 1q21+ plus del17p or t(4;14) exhibited an inferior prognosis compared to those with 1q21+ alone. Our results suggested that double-hit multiple myeloma was associated with extremely poor survival outcomes, and more effective treatments needed to be explored for this particular subtype of MM.

Insights from Clinical Trials: Evidence-Based Recommendations for Induction Treatment of Newly Diagnosed Transplant-Eligible Multiple Myeloma.

Multiple myeloma (MM) is a hematological malignancy and poses significant therapeutic challenges. This review synthesizes evidence from pivotal clinical trials to guide induction treatment for transplant-eligible (TE), newly diagnosed MM (NDMM) patients. Emphasizing the evolution from three-drug to four-drug induction therapies, we highlight the integration of monoclonal antibodies, particularly CD38 recombinant monoclonal antibody agents, into treatment regimens. This analysis includes a comprehensive literature review of research from major databases and conferences conducted between 2010 and 2023, culminating in the detailed evaluation of 47 studies. The findings underscore the superiority of quadruple regimens in TE NDMM, notably those incorporating daratumumab, in achieving superior responses including progression-free survival (PFS), minimal residual disease (MRD) negativity, objective response rate (ORR), and overall survival (OS) when compared to triple-drug regimens. As treatment regimens evolve with additional agents, the improved outcomes with treatment-related adverse events should be carefully balanced. This review advocates for a paradigm shift towards quadruple induction therapies for TE NDMM, offers a detailed insight into the current landscape of MM treatment, and reinforces a new standard of care.

Mega-dose decitabine conditioning and prophylactic donor lymphocyte infusion for patients with relapsed/refractory AML with active disease at the time of allogeneic haematopoietic cell transplantation: A multicenter prospective phase II study.

Patients with relapsed/refractory acute myeloid leukaemia (R/R AML), especially those who failed in novel target agents are related to dismal survival. We developed a multi-institutional, single-arm, prospective phase II trial, to investigate intensified conditioning with 'Mega-Dose' decitabine (MegaDAC) following allogeneic haematopoietic cell transplantation (allo-HCT) for R/R AML. From 2019 to 2023, 70 heavily treated R/R AML patients in active disease were consecutively enrolled. Significantly, every patient (n = 18) harbouring specific mutations exhibited no response to their best available target agents (BATs). Moreover, 74.3% of the enrolled patients did not reach remission following venetoclax-based regimens. All patients underwent intravenous decitabine (400 mg/m2) along with busulfan and cyclophosphamide. Median follow-up was 26 months (8-65) after HCT. All engrafted patients achieved MRD negativity post-HCT, with a median 3.3-log reduction in recurrent genetic abnormalities. The regimen was well tolerated, without irreversible grades III-IV toxicity peri-engraftment. The estimated 2-year CIR was 29.6% (18.4%-41.7%) and the est-2-year NRM was 15.5% (7.8%-25.5%). The est-2-year LFS, OS, and GRFS were 55.0% (43.5%-69.4%), 58.6% (47.0%-73.0%), and 42.9% (31.9%-57.6%), respectively. Multivariate analysis showed that pre-HCT drug exposures had no significant impact on primary outcomes. MegaDAC is highlighted as an effective and safe option for R/R AML in the new era of targeted therapies.

Epcoritamab in relapsed/refractory large B-cell lymphoma: 2-year follow-up from the pivotal EPCORE NHL-1 trial.

Primary results (median follow-up, 10.7 months) from the pivotal EPCORE® NHL-1 study in relapsed or refractory (R/R) large B-cell lymphoma (LBCL) demonstrated deep, durable responses with epcoritamab, a CD3xCD20 bispecific antibody, when used as monotherapy. We report long-term efficacy and safety results in patients with LBCL (N = 157; 25.1-month median follow-up). As of April 21, 2023, overall response rate was 63.1% and complete response (CR) rate was 40.1%. Estimated 24-month progression-free survival (PFS) and overall survival (OS) rates were 27.8% and 44.6%, respectively. An estimated 64.2% of complete responders remained in CR at 24 months. Estimated 24-month PFS and OS rates among complete responders were 65.1% and 78.2%, respectively. Of 119 minimal residual disease (MRD)-evaluable patients, 45.4% had MRD negativity, which correlated with longer PFS and OS. CR rates were generally consistent across predefined subgroups: 36% prior chimeric antigen receptor (CAR) T-cell therapy, 32% primary refractory disease, and 37% International Prognostic Index ≥3. The most common treatment-emergent adverse events were cytokine release syndrome (51.0%), pyrexia (24.8%), fatigue (24.2%), and neutropenia (23.6%). These results underscore the long-term benefit of epcoritamab for treating R/R LBCL with deep responses across subgroups, including patients with hard-to-treat disease and expected poor prognosis (ClinicalTrials.gov Registration: NCT03625037).

Philadelphia-like B-cell acute lymphoblastic Leukaemia: Disease features and outcomes in the era of immunotherapy.

Philadelphia chromosome (Ph)-like acute lymphoblastic leukaemia (ALL) is a high-risk subtype with a gene expression profile similar to Ph-positive ALL, due to activation of tyrosine kinase signalling. To understand the clinical implications of Ph-like ALL, this single-centre retrospective study evaluates outcomes in 268 adults, largely Hispanic ALL patients treated between 2013 and 2024, with a subgroup analysis of 139 haematopoietic stem cell transplantation (HSCT) patients. ALL subtypes included 68 (25.4%) Ph-like, 89 (33.2%) Ph-positive, and 111 (41.4%) Ph-negative. Ph-like patients were the youngest age at diagnosis (p = 0.007), most likely to have refractory disease (p < 0.001), and least likely to achieve minimal residual disease (MRD) negativity after induction (p = 0.031). Relative to Ph-negative ALL, Ph-like achieved worse event-free survival (EFS) (HR = 1.66; 95% CI 1.12-2.46; p = 0.012), whereas Ph-positive had improved EFS (HR = 0.60; 95% CI 0.38-0.93; p = 0.024) and cumulative incidence of relapse (CIR) (HR = 0.59; 95% CI 0.35-0.99; p = 0.046). Within the transplant subgroup, Ph status did not impact disease-free survival (DFS), CIR, or overall survival (OS). However, patients who received blinatumomab within 1-year pre-HSCT had improved DFS (HR = 0.43; 95% CI 0.20-0.94; p = 0.034) and CIR (HR = 0.26; 95% CI 0.09-0.75; p = 0.13). In conclusion, our data suggest that Ph-like is less likely to respond to standard induction therapy and HSCT may result in similar survival outcomes to Ph-negative ALL.