Refractory Acute Myeloid Leukemia Research Articles

Abstract 6728: Preclinical development of QL325, a novel T cell engager targeting CLEC12A-positive AML

Abstract Despite advancement in targeted therapies, treatment options for patients with acute myeloid leukemia (AML) that provide a tolerable and durable response remain elusive. We have developed a CD3 bispecific antibody, QL325, targeting CLEC12A, a c-type lectin protein that is highly expressed on AML blasts. Normally, CLEC12A expression is mostly confined to the CD34+CD38- progenitor population and largely absent on normal and regenerating bone marrow stem cells. Our bispecific antibody is configured in a 2 + 1 format, with bivalent avidity binding to CLEC12A, monovalent low affinity binding to CD3, and an effector-null Fc for extending half-life. In our preclinical studies, QL325 induced CLEC12A -dependent activation and proliferation of T cells. Redirected T cell-dependent cytotoxicity mediated by QL325 was restricted to AML cancer cells expressing CLEC12A. QL325 demonstrated dose dependent suppression of tumor growth in xenograft models of AML, significantly more potent than a clinical benchmark antibody. In non-human primates, QL325 was tolerated up to 0.03 mg/kg for IV dosing and under 0.1 mg/kg for SC dosing, well above the predicted effective therapeutic dose. A phase 1 clinical trial is currently ongoing to determine the safety and early efficacy in patients with refractory or relapsed AML. Citation Format: Shenda Gu, Hieu V. Tran, Shihao Chen, Ke Liu, Xin Zhang, Linchao Jia, Ruixue Ma, Jiayu Fu. Preclinical development of QL325, a novel T cell engager targeting CLEC12A-positive AML [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 6728.

Abstract 7123: Biomarker-targeted alkylator and DNA damage repair inhibitor combination for refractory and relapsed acute myeloid leukemia (AML)

Abstract Isocitrate dehydrogenase 1 and 2 (IDH1/2) convert isocitrate to α-ketoglutarate in the tricarboxylic acid (TCA) cycle. A missense mutation in IDH1/2 leads to accelerated conversion of α-ketoglutarate into 2-hydroxyglutarate (2-HG), an oncometabolite that competitively inhibits α-ketoglutarate-dependent dioxygenases including Ten-Eleven Translocation (TET) enzymes. TET enzymes are DNA demethylases that convert 5-methylcytosine to 5-carboxycytosine and regulate CpG island promoter methylation signatures. In IDH1/2 mutant glioma, inhibition of TET2 enzyme by 2-HG can lead to promoter hypermethylation of O6-methylguanine methyltransferase (MGMT) and reduce its expression. Approximately 10-15% of de novo or treatment-related AML harbor mutually exclusive mutations in IDH1/2 or TET2, and emerging resistance towards clinical IDH1/2 inhibitors, therefore warrants novel therapeutic options. We performed a pan-cancer TCGA analysis and observed MGMT promoter hypermethylation and reduced expression in IDH1/2 AML. Our independent study on 10 AML patients (5 IDH1/2 and 5 TET2 mutant) corroborated the TCGA data and showed a significantly reduced expression of MGMT in comparison to 7 wild-type AML samples. As MGMT resolves O6-alkylguanine lesions during DNA damage, we performed an exhaustive alkylator screen, where temozolomide (TMZ) and our novel compound KL-50 emerged as the top hits that imparted a maximum therapeutic index in multiple MGMT (MGMT+/–) isogenic AML cell line models. Both TMZ and KL-50 induced MGMT-dependent DNA strand breaks and replication stress and activated ATM and ATR DNA damage response pathways in a time-dependent manner. Inhibition of ATR activation with Ceralasertib, an ATR inhibitor (ATRi) currently in clinical trials for chronic myelomonocytic leukemia and myelodysplastic syndromes, imparted a profound MGMT-dependent synergy with TMZ and KL-50. Researchers have established in glioma that mismatch repair (MMR) loss confers resistance to TMZ, and reported studies also show evidence of MMR loss in refractory or relapsed AML patients. Thus, we developed numerous MMR-deficient isogenic AML cell lines in an MGMT+/– background and observed MMR loss-mediated resistance to TMZ and abrogation of its synergy with ATRi. Unlike TMZ, KL-50 retained a profound synergy with ATRi in an MGMT-dependent manner irrespective of MMR status. We are currently investigating our novel KL-50 and ATRi combination in MGMT/MMR isogenic cell line-based in vivo AML models and in AML patient-derived xenografts to establish it as a promising novel biomarker-targeted therapy for AML patients. Citation Format: Prateek Bhardwaj, Ranjini Sundaram, Amro Baassiri, Martin Matthews, Jennifer VanOudenhove, Susan Gueble, Stephanie Halene, Ranjit Bindra. Biomarker-targeted alkylator and DNA damage repair inhibitor combination for refractory and relapsed acute myeloid leukemia (AML) [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 7123.

FLAG/FLAG-Ida Regimen in Secondary and Relapsed/Refractory Acute Myeloid Leukemia-Even in the Era of New Treatment Modalities Still a Significant Player.

(1) Background: Relapsed/refractory (r/r) and secondary acute myeloid leukemia are highlighted by chemoresistance and poor outcomes. The aim of the study was to assess the efficacy and toxicity of fludarabine, cytarabine, and granulocyte-colony stimulation factor (FLAG) with or without idarubicin (-Ida) and to discuss novel therapies in this setting. (2) Methods: Clinical and cytogenetic data on 130 consecutive patients with r/r and secondary AML treated at our center were retrospectively analyzed. (3) Results: There were 48, 56, and 26 patients with relapsed, refractory, and secondary AML, respectively. The median age was 60 years. The overall response was achieved in 70% of patients. The median overall survival (OS) time for the whole group was 9.4 months. In total, 47% of patients proceeded to allogeneic hematopoietic stem cell transplantation (aHSCT) and these patients had significantly prolonged OS compared to the others (63 months vs. 4.2 months; p < 0.001). Among the variables, including age, FLT3 mutation status, European LeukemiaNet (ELN) 2022 classification risk, FLAG vs. FLAG-Ida, and aHSCT, a multivariate analysis revealed that only aHSCT significantly influenced overall survival. (4) Conclusions: FLAG(-Ida) chemotherapy remains an effective salvage chemotherapy for patients with r/r and secondary AML with a plan of proceeding to aHSCT.

A phase 1 study of the irreversible FLT3 inhibitor FF-10101 in relapsed or refractory acute myeloid leukemia

AbstractFLT3 tyrosine kinase inhibitors (TKIs) have clinical efficacy for patients with FLT3-mutated AML (acute myeloid leukemia), but their impact is limited by resistance in the setting of monotherapy and by tolerability problems when used in combination therapies. FF-10101 is a novel compound that covalently binds to a cysteine residue near the active site of FLT3, irreversibly inhibiting receptor signaling. It is effective against most FLT3 activating mutations, and, unlike other inhibitors, is minimally vulnerable to resistance induced by FLT3 ligand. We conducted a phase 1 dose escalation study of oral FF-10101 in patients with relapsed and/or refractory AML, the majority of whom harbored FLT3-activating mutations and/or had prior exposure to FLT3 inhibitors. Fifty-four participants enrolled in cohorts receiving doses ranging from 10 to 225 mg per day and 50 to 100 mg twice daily (BID). The dose limiting toxicities were diarrhea and QT prolongation. Among 40 response-evaluable participants, the composite complete response rate was 10%, and the overall response rate (including partial responses) was 12.5%, including patients who had progressed on gilteritinib. Overall, 56% of participants had prior exposure to FLT3 inhibitors. The recommended phase 2 dose was 75 mg BID. FF-10101 potentially represents a next-generation advance in the management of FLT3-mutated AML. This trial was registered at www.ClinicalTrials.gov as #NCT03194685.

Efficacy and safety of cladribine in combination with busulfan and cyclophosphamide as an intensive conditioning regimen preceding allogeneic hematopoietic stem cell transplantation in relapsed or refractory acute myeloid leukemia

BackgroundCladribine, an analogue of deoxyadenosine, is used for therapy of hematological malignancies. Cladribine-containing regimen has been recommended as a rescue therapy for relapsed or refractory (R/R) acute myeloid leukemia (AML). Its combination with busulfan plus cyclophosphamide (BuCy), as an intensive conditioning regimen prior to allogeneic hematopoietic stem cell transplantation (allo-HSCT), requires more clinical evidence. This study aimed to explore the efficacy and safety of cladribine plus BuCy administered as an intensive conditioning regimen before allo-HSCT in R/R AML patients. MethodsTwenty-three R/R AML patients, who underwent cladribine plus BuCy intensive conditioning regimen before allo-HSCT, were retrospectively analyzed. The median (range) follow-up duration time of observation was 0.73 (0.08–2.69) years. ResultsThe median (range) returned levels of mononuclear cells were 11.5 (6.1–18.5) x 108/kg and CD34+ cells were 5.5 (3.5–9.3) x 106/kg. The median (range) time of platelet reconstitution was 13.0 (9.0–21.0) days and neutrophil reconstitution was 14.0 (11.0–26.0) days. The incidence of conditioning regimen related toxicity (CRRT) affected 69.6% of patients; all CRRT-affected patients had grade I-II symptoms, including gastrointestinal tract (39.1%), oral cavity (26.1%), liver (8.7%), and kidney (4.3%) CRRTs. The incidence of acute graft-versus-host disease (GVDH) included 30.4% among all patients with 4.3% of grade III-IV acute GVHD, and 34.8% of chronic GVHD. During the follow-up period, 4 (17.4%) patients relapsed, and 6 (26.1%) patients died (cause of death: disease relapse, n = 3; infection, n = 2; GVHD, n = 1). The 1-year and 2-year accumulating event-free survival rates were 66.3% and 53.1%, respectively. The 1-year accumulating overall survival rate was 74.7% and 2-year survival rate was 64.0%. ConclusionCladribine plus BuCy intensive conditioning regimen before allo-HSCT exhibits favorable treatment efficacy with acceptable toxicity in R/R AML patients.

Integrating Full Bayesian Inference and Student's t-Distribution Method for Enhanced Outlier Handling in Caffeine Population Pharmacokinetics: Assessing Drug-Drug Interactions with Enasidenib in Relapsed or Refractory AML and MDS Patients.

As the first-in-class, selective, and potent inhibitor of the isocitrate dehydrogenase-2 (IDH2) mutant protein, enasidenib was approved by the US Food and Drug Administration (FDA) in 2017 for the treatment of adult patients with relapsed or refractory acute myeloid leukemia (AML) with an IDH2 mutation. Known for its interactions with various cytochrome P450 (CYP)enzymes and transporters in vitro, a clinical pharmacokinetics (PK) trial was initiated to assess the impact of multiple doses of enasidenib on the single-dose PK of sensitive probe substrates of several cytochrome P450 enzymes and transporters. In this study, a population pharmacokinetic analysis approach was employed to address challenges posed by high, nonzero baseline caffeine concentrations. Moreover, we integrated full Bayesian inference into this approach innovatively for a more detailed understanding of parameter uncertainty and greater modeling flexibility, alongside Student's t-distribution for robust error modeling in handling the abnormal outlier caffeine concentration data observed in this trial. Our analyses demonstrated that multiple doses of enasidenib altered caffeine clearance to a clinically meaningful extent, as evidenced by an approximate 8-fold decrease. This finding led to a specific recommendation in the package insert to avoid the concurrent use of certain CYP1A2 substrates with enasidenib, unless directed otherwise in the prescribing information. Furthermore, this research underlines the technical benefits of integrating full Bayesian inference and incorporating Student's t-distribution for residual error modeling in the PK field.

Oral decitabine and cedazuridine plus venetoclax for older or unfit patients with acute myeloid leukaemia: a phase 2 study

Hypomethylating agents combined with venetoclax are effective regimens in patients with acute myeloid leukaemia who are ineligible for intensive chemotherapy. Decitabine and cedazuridine (ASTX727) is an oral formulation of decitabine that achieves equivalent area-under-curve exposure to intravenous decitabine. We performed a single centre phase 2 study to evaluate the efficacy and safety of ASTX727 plus venetoclax. This study enrolled patients with newly diagnosed (frontline treatment group) acute myeloid leukaemia who were ineligible for intensive chemotherapy (aged ≥75 years, an Eastern Cooperative Oncology Group [ECOG] performance status of 2-3, or major comorbidities) or relapsed or refractory acute myeloid leukaemia. Being aged 18 years or older and having an ECOG performance status of 2 or less were requirements for the relapsed or refractory disease treatment cohort, without any limits in the number of previous lines of therapy. Treatment consisted of ASTX727 (cedazuridine 100 mg and decitabine 35 mg) orally for 5 days and venetoclax 400 mg orally for 21-28 days in 28-day cycles. The primary outcome was overall response rate of ASTX727 plus venetoclax. Living patients who have not completed cycle one were not evaluable for response. Safety was analysed in all patients who started treatment. This study was registered on ClinicalTrials.gov (NCT04746235) and is ongoing. The data cutoff date for this analysis was Sept 22, 2023. Between March 16, 2021, and Sept 18, 2023, 62 patients were enrolled (49 frontline and 13 relapsed or refractory) with a median age of 78 years (IQR 73-82). 36 (58%) were male; 53 (85%) were White, 4 (6%) Black, 2 (3%) Asian and 3 (5%) other or did not answer. 48 (77%) of 62 patients were European LeukemiaNet 2022 adverse risk, 24 (39%) had antecedent myelodysplastic syndromes, 12 (19%) had previously failed a hypomethylating agent, ten (16%) had therapy-related acute myeloid leukaemia, and 11 (18%) had TP53 mutations. The median follow-up time was 18·3 months (IQR 8·8-23·3). The overall response rate was 30 (64%) of 47 patients (95% CI 49-77) in frontline cohort and six (46%) of 13 patients (19-75) in relapsed or refractory cohort. The most common grade 3 or worse treatment-emergent adverse events were febrile neutropenia in 11 (18%) of 62 patients, pneumonia in eight (13%), respiratory failure in five (8%), bacteraemia in four (6%), and sepsis in four (6%). Three deaths occurred in patients in remission (one sepsis, one gastrointestinal haemorrhage, and one respiratory failure) and were potentially treatment related. ASTX727 plus venetoclax is an active fully oral regimen and safe in most older or unfit patients with acute myeloid leukaemia. Our findings should be confirmed in larger multicentric studies. MD Anderson Cancer Center Support Grant, Myelodysplastic Syndrome/Acute Myeloid Leukaemia Moon Shot, Leukemia SPORE, Taiho Oncology, and Astex Pharmaceuticals.

Results of treating relapsed and refractory acute myeloid leukemia at a reference center in Latin America: the importance of outpatient hematopoietic stem cell transplantation

Results of treating relapsed and refractory acute myeloid leukemia at a reference center in Latin America: the importance of outpatient hematopoietic stem cell transplantation

Efficacy and safety of mitoxantrone, etoposide, and cytarabine for treatment of relapsed or refractory acute myeloid leukemia

Background/rationaleMost patients with acute myeloid leukemia (AML) develop relapsed or refractory (R/R) disease after receiving initial induction chemotherapy. Salvage chemotherapy followed by allogeneic hematopoietic stem cell transplantation (alloHSCT) is the only curative therapy for R/R AML. Mitoxantrone, etoposide, and cytarabine (MEC) is the current standard of care salvage regimen for R/R AML at Cleveland Clinic. The primary objective was to determine the overall remission rate (ORR: defined as patients achieving complete remission (CR) or complete remission with incomplete hematologic recovery (CRi)) in R/R AML patients who received MEC. MethodsAdult patients with R/R AML treated with MEC between July 1, 2014 and September 30, 2022 were included. ORR and its association with baseline characteristics were determined. Secondary outcomes included overall survival (OS), event-free survival (EFS), relapse-free survival (RFS), and safety. ResultsSixty patients were evaluated. The ORR was 51.7% (33.3% CR and 18.3% CRi). The median time from receipt of MEC to CR/CRi was 7.7 weeks. Patients with bone marrow blasts ≤20% and peripheral blood blasts ≤30% at MEC initiation were more than twice as likely to achieve CR/CRi compared to those with a higher blast burden. The median OS was 6.3 months. Twenty-four (40.0%) patients proceeded to alloHSCT. Twenty-one (35.0%) patients were transferred to the intensive care unit (ICU) during their admission. ConclusionsMEC is an effective salvage regimen for patients with R/R AML, especially among those with low disease burden at initiation. Febrile neutropenia, infections, and severe oral mucositis were common with MEC administration.

Pivekimab sunirine (IMGN632), a novel CD123-targeting antibody–drug conjugate, in relapsed or refractory acute myeloid leukaemia: a phase 1/2 study

Pivekimab sunirine (IMGN632) is a first-in-class antibody-drug conjugate comprising a high-affinity CD123 antibody, cleavable linker, and novel indolinobenzodiazepine pseudodimer payload. CD123 is overexpressed in several haematological malignancies, including acute myeloid leukaemia. We present clinical data on pivekimab sunirine in relapsed or refractory acute myeloid leukaemia. This first-in-human, phase 1/2 dose-escalation and dose-expansion study enrolled participants aged 18 years or older at nine hospitals in France, Italy, Spain, and the USA with CD123+ haematological malignancies (Eastern Cooperative Oncology Group performance status of 0-1); participants reported here were in a cohort of participants with acute myeloid leukaemia who were refractory to or had relapsed on one or more previous treatments for acute myeloid leukaemia. The 3 + 3 dose-escalation phase evaluated two dosing schedules: schedule A (once every 3 weeks, on day 1 of a 3-week cycle) and fractionated schedule B (days 1, 4, and 8 of a 3-week cycle). The dose-expansion phase evaluated two cohorts: one cohort given 0·045 mg/kg of bodyweight (schedule A) and one cohort given 0·090 mg/kg of bodyweight (schedule A). The primary endpoints were the maximum tolerated dose and the recommended phase 2 dose. Antileukaemia activity (overall response and a composite complete remission assessment) was a secondary endpoint. The study is ongoing and registered with ClinicalTrials.gov, NCT03386513. Between Dec 29, 2017, and May 27, 2020, 91 participants were enrolled (schedule A, n=68; schedule B, n=23). 30 (44%) of schedule A participants were female and 38 (56%) were male; 60 (88%) were White, six (9%) were Black or African American, and two (3%) were other races. Pivekimab sunirine at doses of 0·015 mg/kg to 0·450 mg/kg in schedule A was administered in six escalating doses with no maximum tolerated dose defined; three dose-limiting toxicities were observed (reversible veno-occlusive disease; 0·180 mg/kg, n=1 and 0·450 mg/kg, n=1; and neutropenia; 0·300 mg/kg, n=1). Schedule B was not pursued further on the basis of comparative safety and antileukaemia findings with schedule A. The recommended phase 2 dose was selected as 0·045 mg/kg once every 3 weeks. At the recommended phase 2 dose (n=29), the most common grade 3 or worse treatment-related adverse events were febrile neutropenia (three [10%]), infusion-related reactions (two [7%]), and anaemia (two [7%]). Treatment-related serious adverse events occurring in 5% or more of participants treated at the recommended phase 2 dose were febrile neutropenia (two [7%]) and infusion-related reactions (two [7%]). Among 68 participants who received schedule A, one death (1%) was considered to be treatment-related (cause unknown; 0·300 mg/kg cohort). At the recommended phase 2 dose, the overall response rate was 21% (95% CI 8-40; six of 29) and the composite complete remission rate was 17% (95% CI 6-36; five of 29). Pivekimab sunirine showed single-agent activity across multiple doses, with a recommended phase 2 dose of 0·045 mg/kg once every 3 weeks. These findings led to a phase 1b/2 study of pivekimab sunirine plus azacitidine and venetoclax in patients with CD123-positive acute myeloid leukaemia. ImmunoGen.

Venetoclax with decitabine or azacitidine in relapsed or refractory acute myeloid leukemia.

Relapsed or refractory acute myeloid leukemia (AML) is associated with poor outcomes and resistance to therapy. The addition of venetoclax, a BCL-2 antagonist, to lower-intensity therapies results in improved survival in the first-line setting compared to monotherapy with a hypomethylating agent or low-dose cytarabine. Despite this, much remains unknown about the performance of venetoclax with a hypomethylating agent following the first-line setting. Additionally, while the ELN 2022 guidelines appear to improve the prognostication of AML, clarification is needed to determine how the revision applies to lower-intensity strategies. To investigate this, we retrospectively analyzed the performance of venetoclax with decitabine or azacitidine in relapsed or refractory AML under the ELN 2022 guidelines. We demonstrated that the ELN 2022 revision is not optimized for lower-intensity venetoclax-based strategies. To refine the prognostication schema, we showed significantly improved response and survival benefits for patients with mutated NPM1 and IDH. Relatively, patients with mutated NRAS, KRAS, and FLT3-ITD were associated with inferior response and survival. Furthermore, there is an unmet clinical need for tools to improve the selection of lower-intensity therapy candidates with borderline functional status. Using an incremental survival computation method, we discovered that a CCI score threshold of 5 distinguishes patients at an elevated risk of death. Together, these novel findings highlight areas of refinement to improve survival in relapsed or refractory AML.

CD155/PVR determines acute myeloid leukemia targeting by Delta One T cells

AbstractRelapsed or refractory acute myeloid leukemia (AML) remains a major therapeutic challenge. We have recently developed a Vδ1+ γδ T cell–based product for adoptive immunotherapy, named Delta One T (DOT) cells, and demonstrated their cytolytic capacity to eliminate AML cell lines and primary blasts in vitro and in vivo. However, the molecular mechanisms responsible for the broad DOT-cell recognition of AML cells remain poorly understood. Here, we dissected the role of natural killer (NK) cell receptor ligands in AML cell recognition by DOT cells. Screening of multiple AML cell lines highlighted a strong upregulation of the DNAM-1 ligands, CD155/pulmonary vascular resistance (PVR), CD112/nectin-2, as well as the NKp30 ligand, B7-H6, in contrast with NKG2D ligands. CRISPR-mediated ablation revealed key nonredundant and synergistic contributions of PVR and B7-H6 but not nectin-2 to DOT-cell targeting of AML cells. We further demonstrate that PVR and B7-H6 are critical for the formation of robust immunological synapses between AML and DOT cells. Importantly, PVR but not B7-H6 expression in primary AML samples predicted their elimination by DOT cells. These data provide new mechanistic insight into tumor targeting by DOT cells and suggest that assessing PVR expression levels may be highly relevant to DOT cell–based clinical trials.

Increased expression of CD70 in relapsed acute myeloid leukemia after hypomethylating agents.

Acute myeloid leukemia (AML) is the most common acute leukemia in adults. While induction chemotherapy leads to remission in most patients, a significant number will experience relapse. Therefore, there is a need for novel therapies that can improve remission rates in patients with relapsed and refractory AML. CD70 is the natural ligand for CD27 (a member of the TNF superfamily) and appears to be a promising therapeutic target. Consequently, there is considerable interest in developing chimeric antigen receptor (CAR) T-cell therapy products that can specifically target CD70 in various neoplasms, including AML. In this study, we employed routine diagnostic techniques, such as immunohistochemistry and flow cytometry, to investigate the expression of CD70 in bone marrow samples from treatment-naïve and relapsed AML patients after hypomethylating agents (HMA). Also, we evaluated the impact of HMA on CD70 expression and examined CD70 expression in various leukemic cell subsets and normal hematopoietic progenitors.

SLC25A51 decouples the mitochondrial NAD+/NADH ratio to control proliferation of AML cells

SLC25A51 selectively imports oxidized NAD+ into the mitochondrial matrix and is required for sustaining cell respiration. We observed elevated expression of SLC25A51 that correlated with poorer outcomes in patients with acute myeloid leukemia (AML), and we sought to determine the role SLC25A51 may serve in this disease. We found that lowering SLC25A51 levels led to increased apoptosis and prolonged survival in orthotopic xenograft models. Metabolic flux analyses indicated that depletion of SLC25A51 shunted flux away from mitochondrial oxidative pathways, notably without increased glycolytic flux. Depletion of SLC25A51 combined with 5-azacytidine treatment limits expansion of AML cells invivo. Together, the data indicate that AML cells upregulate SLC25A51 to decouple mitochondrial NAD+/NADH for a proliferative advantage by supporting oxidative reactions from a variety of fuels. Thus, SLC25A51 represents a critical regulator that can be exploited by cancer cells and may be a vulnerability for refractory AML.

Venetoclax in combination with azacitidine or decitabine in relapsed/refractory acute myeloid leukemia

Purpose: To investigate the clinical effects of venetoclax combined with azacitidine or decitabine in relapsed/refractory acute myeloid leukemia.&#x0D; Methods: 208 eligible first-line participants, who were diagnosed and treated for relapsed/refractory acute myeloid leukemia between January 2022 and December 2022, were recruited from the Department of Hematology of Loudi Central Hospital, China. The patients were randomly divided into study and control groups at the point of recruitment. Patients in the control group received venetoclax combined with decitabine, while those in the study group received venetoclax in combination with azacitidine. Clinical data for the two groups were recorded. The primary endpoints of this study included efficacy, routine blood indices, and adverse reactions. &#x0D; Results: There was no statistically significant difference in baseline characteristics between the two groups (p &gt; 0.05), indicating comparability. The total effectiveness of the treatment (i.e., efficacy) in the study group was higher than in the control group (p &lt; 0.05), while the control group had a higher risk of platelet, red blood cell, and neutrophil absolute count reduction than the study group (p &lt; 0.05). The platelet count and hemoglobin level were lower in the control group after treatment compared to the study group (p &lt; 0.05). &#x0D; Conclusion: The combination of venetoclax with azacitidine improves the efficacy and blood routine indices of patients with relapsed/ refractory acute myeloid leukemia, while reducing adverse reactions.

131I-Apamistamab Improves Outcomes in Patients 65 Years and Older with Relapsed or Refractory AML

131I-Apamistamab Improves Outcomes in Patients 65 Years and Older with Relapsed or Refractory AML

Analysis of the Efficacy and Prognosis Factors of Acute Myeloid Leukemia with a Combination Therapy of Venetoclax

To explore the efficacy and prognosis factors of acute myeloid leukemia with a combination therapy of venetoclax. A retrospective analysis was performed on the clinical data of AML patients treated with a combination therapy of venetoclax from March 2020 to April 2023 in the First Hospital of Lanzhou University. The efficacy, adverse reactions and survival were observed, and the influencing factors were analyzed. A total of 74 AML patients were included in this study, including 43 initially treated AML and 31 relapsed or refractory AML (R/R AML). The median age of 43 initially treated AML patients was 65 years old, the composite complete remission (cCR) rate was 67.4% (29/43), the objective response rate (ORR) was 72.1% (31/43), and the median overall survival (OS) was 17.3 months. The median age of 31 R/R AML patients was 51 years old, with a cCR rate of 38.7% (12/31), an ORR of 58.1% (18/31), and a median OS of 7.1 months. Sex, the blood cell count before VEN, gene mutation and prognosis stratification were related to whether to obtain cCR. Failure to obtain cCR was an independent risk factor for adverse outcomes. A combination therapy of venetoclax is safe and efficacious for AML. Its efficacy and survival are affected by molecular biology, cytogenetics and other factors.

Paired single-B-cell transcriptomics and receptor sequencing reveal activation states and clonal signatures that characterize B cells in acute myeloid leukemia

BackgroundAcute myeloid leukemia (AML) is associated with a dismal prognosis. Immune checkpoint blockade (ICB) to induce antitumor activity in AML patients has yielded mixed results. Despite the pivotal role of...

Gilteritinib in combination with venetoclax, low-dose cytarabine and actinomycin D for relapsed or refractory FLT3-mutated acute myeloid leukaemia.

We have conducted a retrospective, single-centre analysis of 20 patients with relapsed or refractory FLT3-mutated acute myeloid leukaemia (FLT3m AML) who received a salvage quadruplet regimen consisting of gilteritinib, venetoclax, low-dose cytarabine and actinomycin D (G-ACTIVE). G-ACTIVE resulted in a 95% (19/20) overall response rate and 75% (15/20) complete remission and complete remission with an incomplete platelet recovery (CR + CRp) rate. Out of 13 transplant-eligible patients, 11 (86%) proceeded to an allogeneic stem cell transplantation. The median overall survival and relapse-free survival after G-ACTIVE were 32 and 12.9 months respectively. The Day 60 mortality rate was 15%.

Azacitidine, Venetoclax, and Gilteritinib in Newly Diagnosed and Relapsed or Refractory FLT3-Mutated AML.

Azacitidine plus venetoclax is a standard of care for patients with newly diagnosed AML who are unfit for intensive chemotherapy. However, FLT3 mutations are a common mechanism of resistance to this regimen. The addition of gilteritinib, an oral FLT3 inhibitor, to azacitidine and venetoclax may improve outcomes in patients with FLT3-mutated AML. This phase I/II study evaluated azacitidine, venetoclax, and gilteritinib in two cohorts: patients with (1) newly diagnosed FLT3-mutated AML who were unfit for intensive chemotherapy or (2) relapsed/refractory FLT3-mutated AML (ClinicalTrials.gov identifier: NCT04140487). The primary end points were the maximum tolerated dose of gilteritinib (phase I) and the combined complete remission (CR)/CR with incomplete hematologic recovery (CRi) rate (phase II). Fifty-two patients were enrolled (frontline [n = 30]; relapsed/refractory [n = 22]). The recommended phase II dose was gilteritinib 80 mg once daily in combination with azacitidine and venetoclax. In the frontline cohort, the median age was 71 years and 73% of patients had an FLT3-internal tandem duplication (ITD) mutation. The CR/CRi rate was 96% (CR, 90%; CRi, 6%). Sixty-five percent of evaluable patients achieved FLT3-ITD measurable residual disease <5 × 10-5 within four cycles. With a median follow-up of 19.3 months, the median relapse-free survival (RFS) and overall survival (OS) have not been reached and the 18-month RFS and OS rates are 71% and 72%, respectively. In the relapsed/refractory cohort, the CR/CRi rate was 27%; nine additional patients (41%) achieved a morphologic leukemia-free state. The most common grade 3 or higher nonhematologic adverse events were infection (62%) and febrile neutropenia (38%), which were more frequent in the relapsed/refractory cohort. The combination of azacitidine, venetoclax, and gilteritinib resulted in high rates of CR/CRi, deep FLT3 molecular responses, and encouraging survival in newly diagnosed FLT3-mutated AML. Myelosuppression was manageable with mitigative dosing strategies.