Venetoclax plus LDAC for newly diagnosed AML ineligible for intensive chemotherapy: a phase 3 randomized placebo-controlled trial

Efficacy and safety of venetoclax-based combination therapy for previously untreated acute myeloid leukemia: a meta-analysis

PURPOSE

To explore the efficacy and safety of venetoclax-based combination therapy for older patients with newly diagnosed acute myeloid leukemia (AML).

METHODS

We performed a systematic review and meta-analysis of clinical trials comparing venetoclax plus hypomethylating agents (HMAs) or low-dose cytarabine (LDAC) with mono-HMAs or LDAC. The random or fixed effects model was applied to the studies based on heterogeneity. Dichotomous data were summarized using the risk ratio (RR) and 95% confidence interval (CI). Continuous variable data were reported as weighted mean differences (WMDs).

RESULTS

Nine studies, including a total of 1232 patients, were included in this meta-analysis. Thec complete remission (CR)/complete remission with incomplete hematological recovery (CRi) rate of the venetoclax (Ven) + azacytidine (Aza) group was significantly greater than that of the Aza monotherapy group (RR: 2.42; 95% CI: 1.85-3.15; P < 0.001). Similarly, the CR/CRi rate of the Ven + LDAC group was also significantly greater than that of the LDAC monotherapy group (RR: 2.57; 95% CI: 1.58-4.17; P = 0.00). The same results were observed for OS among these groups. However, the incidence of febrile neutropenia was greater in the Ven + Aza group than in the Ven + Decitabine (Dec) or monotherapy Aza group (RR: 0.69; 95% CI: 0.53-0.90; P = 0.006 and RR: 2.19; 95% CI: 1.58-3.03; P < 0.001, respectively). In addition, the Ven + LDAC group had significantly greater rates of constipation, diarrhea, nausea, and vomiting than the LDAC monotherapy group, with RRs and CIs of 0.61 (95% CI 0.44-0.83, P = 0.002), 1.81 (95% CI 1.22-2.67, P = 0.003), 1.39 (95% CI 1.06-1.82, P = 0.016), and 1.80 (95% CI 1.19-2.72, P = 0.005), respectively.

CONCLUSION

Venetoclax combined with azacitidine, decitabine, or LDAC significantly improved the CR/CRi and OS of patients with previously untreated AML. However, venetoclax plus azacitidine or LDAC was more likely to lead to increased febrile neutropenia and gastrointestinal toxicity.

Myeloid neoplasms post cytotoxic therapy: epidemiology, pathogenesis outcomes, prognostic factors, and treatment options

Myeloid neoplasms post cytotoxic therapy (MN-pCT) are a category includes AML, MDS, and MDS/MPN arising in patients exposed to cytotoxic (DNA-damaging) therapy for an unrelated condition in 2022 version World Health Organization (WHO) classification. With improved survival of patients with tumors, the incidence of MN-pCT after chemotherapy and/or radiation therapy among patients with tumors has gradually risen. However, the outcome of MN-pCT is poorer than that of primary myeloid neoplasms. This review summarizes the current understanding based on existing research, as a foundation for further research on MN-pCT.

The role of long noncoding RNAs in the diagnosis, prognosis and therapeutic biomarkers of acute myeloid leukemia

Acute myeloid leukemia (AML) is the abnormal proliferation of immature myeloid blast cells in the bone marrow. Currently, there are no universally recognized biomarkers for the early diagnosis, prognosis and effective treatment of AML to improve the overall survival of patients. Recent studies, however, have demonstrated that long noncoding RNAs (lncRNAs) are promising targets for the early diagnosis, prognosis and treatment of AML. A critical review of available data would be important to identify study gaps and provide perspectives. In this review, we explored comprehensive information on the potential use of lncRNAs as targets for the diagnosis, prognosis, and treatment of AML. LncRNAs are nonprotein-coding RNAs that are approximately 200 nucleotides long and play important roles in the regulation, metabolism and differentiation of tissues. In addition, they play important roles in the diagnosis, prognosis and treatment of different cancers, including AML. LncRNAs play multifaceted roles as oncogenes or tumor suppressor genes. Recently, deregulated lncRNAs were identified as novel players in the development of AML, making them promising prognostic indicators. Given that lncRNAs could have potential diagnostic marker roles, the lack of sufficient evidence identifying specific lncRNAs expressed in specific cancers hampers the use of lncRNAs as diagnostic markers of AML. The complex roles of lncRNAs in the pathophysiology of AML require further scrutiny to identify specific lncRNAs. This review, despite the lack of sufficient literature, discusses the therapeutic, diagnostic and prognostic roles of lncRNAs in AML and provides future insights that will contribute to studies targeting lncRNAs in the diagnosis, treatment, and management of AML.

Venetoclax Combined With FLAG-IDA in Refractory or Relapsed Acute Myeloid Leukemia

INTRODUCTION

The prognosis of patients with refractory or relapsed AML (R/R-AML) is very limited. To (re)achieve complete remission, there has recently been increasing evidence that the combination of venetoclax (VEN) with chemotherapy is associated with improved outcomes.

PATIENTS AND METHODS

Our retrospective, single-center study of 53 R/R-AML patients with a median follow-up time of 11.0 months compared standard salvage chemotherapy (FLAG-Ida or HAM in n = 35 patients) with a combination of venetoclax (VEN) and FLAG-Ida (FLAVIDA in n = 18 patients) concerning safety and efficacy.

RESULTS

Regarding the primary endpoints, there was a statistically significant increased event free survival (EFS) in the FLAVIDA group compared to patients with standard chemotherapy based on the univariate log-rank-test and in the multivariate Cox regression analysis (HR 0.22 [95% CI 0.05, 0.97]). There were no differences between the two groups in terms of patients developing febrile neutropenia CTCAE III° and IV° or a delay in hematological recovery. In addition, a clear trend towards an improved overall response rate (78% vs. 51%) was demonstrated in the FLAVIDA group.

CONCLUSIONS

The FLAVIDA regimen represents a promising treatment alternative for R/R AML patients with a high response rate and significantly improved EFS compared to standard chemotherapy.

Relapse and resistance in acute myeloid leukemia post venetoclax: improving second lines therapy and combinations

INTRODUCTION

The combined use of the BCL-2 inhibitor venetoclax with azacitidine now is the standard of care for patients with acute myeloid leukemia (AML) unfit for intensive chemotherapy with outcomes exceeding those achieved with hypomethylating agents alone. Venetoclax in combination with intensive chemotherapy is also increasingly used both as frontline as well as salvage therapy. However, resistance to and relapse after venetoclax-based therapies are of major concern and outcomes after treatment failure remain poor.

AREAS COVERED

A comprehensive search was performed using PubMed database (up to April 2024). Studies evaluating venetoclax-based combination treatments in AML and studies assessing markers of response and resistance to venetoclax were investigated. We summarize the status of venetoclax-based therapies in the frontline and relapsed/refractory setting with focus on the main mechanisms of resistance to BCL-2 inhibition. Further, strategies to overcome resistance including combinatorial regimens of hypomethylating agent (HMA) + venetoclax + inhibitors targeting actionable mutations like IDH1/2 or FLT3-ITD and the introduction of novel agents like menin-inhibitors are addressed.

EXPERT OPINION

Although venetoclax is reshaping the treatment of unfit and fit AML patients, prognosis of patients after HMA/VEN failure remains dismal and strategies to abrogate primary and secondary resistance are an unmet clinical need.

Frontline therapy of acute myeloid leukemia with lower intensity regimens: Where are we now and where can we go?

The advent of molecularly targeted therapeutics has transformed the management of patients with acute myeloid leukemia (AML). Particularly for individuals unfit for intensive chemotherapy, lower intensity therapies (LIT) incorporating small molecules have significantly improved patient outcomes. With BCL2, IDH1, IDH2, and FLT3 inhibitors widely used for relapsed AML, combination regimens are now utilized in the frontline. Expansion of these targeted LIT combinations, along with development of novel agents including menin inhibitors, exemplifies the promise of precision medicine. Further understanding of molecular drivers of leukemic transformation and mechanisms of relapse will continue to advance frontline treatment options for patients with AML.

Updates in biology, classification, and management of acute myeloid leukemia with antecedent hematologic disorder and therapy related acute myeloid leukemia

Acute myeloid leukemia with antecedent hematologic disorder (AHD-AML) and therapy related AML (t-AML) constitute a heterogenous disease with inferior outcomes. It is often characterized by high-risk cytogenetic and molecular alterations associated with AHD or prior cancer therapy. Historically, the standard of care treatment has been intensive induction with "7 + 3", with an improved overall response rate and survival with CPX-351. Results from large registry-based studies suggested that allogeneic hematopoietic stem cell transplant is preferable to consolidation chemotherapy alone for achieving long-term survival in patients with AHD-AML. Prevalence of high-risk genetic features and advanced age and comorbidities in patients make AHD-AML and t-AML clinically challenging subgroups to treat with intensive approaches. Recent reports on less intensive treatment options, particularly the hypomethylating agent-venetoclax combination, have shown encouraging response rates in these patients. However, emerging resistance mechanisms compromise duration of response and overall survival. Several novel agents targeting apoptotic machinery, signaling pathways, and immune checkpoints are under clinical investigation, with an aim to truly improve overall outcomes in this subgroup. We reviewed updates in biology, classification, and clinical data comparing safety and efficacy of intensive and less intensive treatment options, and summarized ongoing studies with promising novel therapies in AHD-AML and t-AML.

Recent advances in AML with mutated NPM1

Nucleophosmin 1 (NPM1) mutation is one of the most prevalent genetic mutations in adult acute myeloid leukemia (AML) and is particularly predominant in AML with a normal karyotype. NPM1 is a chaperone protein that plays various roles in several cellular processes. Wild-type NPM1 is normally localized to the nucleus, whereas mutant NPM1 proteins exhibit altered cytoplasmic localization. Clinically, AML with mutated NPM1 without FLT3-ITD is associated with a higher complete remission rate and improved overall survival. AML with mutated NPM1 is categorized as a distinct genetic entity in the World Health Organization classification of hematopoietic malignancies due to its unique clinical and biological features. However, the precise roles of NPM1 in normal hematopoiesis and in AML development remain unclear. Recent studies have revealed various clinical applications of NPM1 mutations in AML treatment, particularly in measurable residual disease analyses that target mutant NPM1 transcripts and in potential therapeutic applications of menin inhibitors and XPO-1 inhibitors for AML with mutated NPM1. Thus, NPM1 mutation is highly significant in AML classification, prognosis, response assessment, and molecular targeted therapies. Here, we review recent progress in clinical and biological aspects of AML with mutated NPM1 including molecular targeted therapy.

A systematic review of venetoclax for the treatment of unfit AML patients in real-world: is all that glitters gold?

Acute myeloid leukemia (AML) is an aggressive hematological disease that mainly affects elderly patients. Following the randomized VIALE-A trial, current standard treatment in patients who are not candidates for intensive chemotherapy consists of the combination of venetoclax (VEN), a selective inhibitor of the anti-apoptotic protein BCL-2, with azacitidine (AZA) or decitabine (DEC). We performed a systematic review to critically assess the growing existing evidence regarding the effectiveness of the VEN-based combinations in unfit adult patients with newly diagnosed AML in the real-world setting. Following PRISMA guidelines, a systematic search of published manuscripts and conference abstracts (European Hematology Association and American Society of Hematology) was conducted (updated March 2024). Primary outcomes were composite complete remission (CRc) and median overall survival (mOS). A total of 73 studies fulfilled inclusion criteria, with a median age of 73 years old. The weighted mean mOS was 10.3 months among 7 138 patients, significantly lower than expected according to the VIALE-A trial (14.7 months), while the weighted mean CRc rate was 58.2% among 5 831 patients, slightly lower to that reported in the VIALE-A (66.4%). Early death rates at 30 and 60 days were 5% and 13%, respectively. The weighted mean percentage of subsequent allogeneic transplant was 15.4%. In conclusion, breakthrough mOS reported in the VIALE-A trial using VEN-AZA was not well reproduced in real world for unfit newly diagnosed AML patients, while CRc rates were more consistent. Strategies to optimize patient selection, dosing regimens, and supportive care are crucial to improve outcomes in real-world.

Molecular Features and Treatment Paradigms of Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a common hematologic malignancy that is considered to be a disease of aging, and traditionally has been treated with induction chemotherapy, followed by consolidation chemotherapy and/or allogenic hematopoietic stem cell transplantation. More recently, with the use of next-generation sequencing and access to molecular information, targeted molecular approaches to the treatment of AML have been adopted. Molecular targeting is gaining prominence, as AML mostly afflicts the elderly population, who often cannot tolerate traditional chemotherapy. Understanding molecular changes at the gene level is also important for accurate disease classification, risk stratification, and prognosis, allowing for more personalized medicine. Some mutations are well studied and have an established gene-specific therapy, including FLT3 and IDH1/2, while others are being investigated in clinical trials. However, data on most known mutations in AML are still minimal and therapeutic studies are in pre-clinical stages, highlighting the importance of further research and elucidation of the pathophysiology involving these genes. In this review, we aim to highlight the key molecular alterations and chromosomal changes that characterize AML, with a focus on pathophysiology, presently available treatment approaches, and future therapeutic options.

Safety, Efficacy, and Predictive Factors of Venetoclax-Based Regimens in Elderly Acute Myeloid Leukemia Patients: A Meta-Analysis

Venetoclax synergizes with low-intensity regimens such as hypomethylating agents (HMAs) and low-dose cytarabine (LDAC). However, less is known about the clinical activity of venetoclax combined with HMAs or LDAC. Therefore, the current study focused on assessing the clinical efficacy, safety, and predictive factors for response to these venetoclax-based regimens in elderly patients with acute myeloid leukemia (AML). A comprehensive search for literature related to our study objective was performed on PubMed, Embase, Web of Science, and Google Scholar databases. The statistical analyses were performed using Review Manager or the Comprehensive Meta-Analysis software. In addition, methodological quality evaluation of nonrandomized studies was conducted using the Newcastle Ottawa Scale, while bias assessment of randomized studies was performed with Cochrane's risk of bias tool. Twelve studies, including 1432 elderly AML patients treated with venetoclax-based regimens, were identified for review and analysis. The pooled analysis showed that the rate of complete response with or without incomplete blood count recovery (CR/CRi) and overall response rate (ORR) among patients treated with venetoclax and HMAs was 59% and 64%, respectively. On the other hand, an CR/CRi of 50% was observed in patients treated with venetoclax and LDAC. Furthermore, venetoclax combined with HMAs demonstrated a significant survival benefit over HMAs alone and intensive chemotherapy (HR: 0.57; 95% CI: 0.47-0.68; P < .00001). The most common grade ≥ 3 hematologic disorder, nonhematological event, and infection in AML patients treated with venetoclax and HMAs were febrile neutropenia (39%), hypokalemia (12%), and pneumonia (19%), respectively. Conversely, thrombocytopenia, hypokalemia, and pneumonia were more common in patients treated with venetoclax and LDAC (41%, 15%, and 12%, respectively). Venetoclax combined with HMAs or LDAC has good clinical activity and a manageable safety profile in elderly patients with AML.

Decitabine in older patients with AML: quality of life results of the EORTC-GIMEMA-GMDS-SG randomized phase 3 trial

ABSTRACT

We hypothesized that fit older patients with acute myeloid leukemia (AML) treated with decitabine (DEC) would report better health-related quality of life (HRQoL) outcomes than those receiving intensive chemotherapy (IC). We conducted a phase 3 randomized trial to compare DEC (10-day schedule) with IC (3+7) in older fit patients with AML. HRQoL was a secondary end point, and it was assessed with the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) in conjunction with its elderly module (EORTC QLQ-ELD14). The following scales were a priori selected for defining the primary end point: physical and role functioning, fatigue, pain, and burden of illness. HRQoL was assessed at baseline, at regeneration from cycle 2, and at 6 and 12 months after randomization, and also before allogeneic hematopoietic stem cell transplantation (allo-HSCT) and 100 days after transplantation. Overall, 606 patients underwent randomization. At 2 months, the risk of HRQoL deterioration was lower in the DEC arm than in the 3+7 arm; 76% (95% confidence interval [CI], 69-82) vs 88% (95% CI, 82-93); odds ratio, 0.43 (95% CI, 0.24-0.76; P = .003). No statistically significant HRQoL differences were observed between treatment arms at the long-term evaluation combining assessments at 6 and 12 months. HRQoL deteriorations between baseline and after allo-HSCT were observed in both arms. However, these deteriorations were not clinically meaningful in patients randomized to DEC, whereas this was the case for those in the 3+7 arm, in 4 of 5 primary HRQoL scales. Our HRQoL findings suggest that lower-intensity treatment with DEC may be preferable to current standard IC (3+7) in fit older patients with AML. This trial was registered at www.clinicaltrials.gov as #NCT02172872.

Venetoclax-based treatment in acute myeloid leukemia: an unexpected bonus on the path to allogeneic hematopoietic stem cell transplant?

Despite the approval of new drugs, the inclusion of -omics-derived data and the integration of machine learning in both the diagnostic and therapeutic process, the prognosis of acute myeloid leukemia (AML) remains dismal. The curative path is still aimed at achieving a successful allogeneic hematopoietic stem cell transplant (HSCT) in most patients. Nevertheless, access to this procedure is limited to eligible patients. Moreover, post-HSCT outcomes are influenced by AML heterogeneity and patient-related factors. The rise of venetoclax (VEN)-based combinations as standard of care in the treatment of older or unfit AML patients, together with their peculiar management profile, has led researchers to evaluate the feasibility of this approach in patients proceeding toward HSCT. We reviewed the available evidence to weigh up the advantages and pitfalls of this new therapeutic strategy.

Treatment of a STAT5b::RARα positive case of APL in a patient not eligible for intensive chemotherapy

Acute promyelocytic leukaemia (APL) with a STAT5b::RARα gene fusion is an extremely rare subtype of APL characterised by resistance to conventional therapies and extremely poor prognosis. This case highlights that whilst APL with variant RARα translocations are rare, they do pose significant challenges both diagnostically and in their clinical management. This case, in the first instance, demonstrates the importance of using a combination of molecular techniques including next generation sequencing (NGS) for diagnosis particularly in morphological and immunophenotypic typical APL which appears negative by confirmatory testing. Secondly, our patient represents, to the best of our knowledge, the first documented example of this rare disease that has been managed with, and shown sensitivity to low-dose cytarabine (LDAC) in combination with venetoclax (Ven). This case demonstrates that although treatment options are extremely limited for patients not eligible for intensive chemotherapy non-intensive options do show increasing promise.

Targeting apoptotic pathways for cancer therapy

Apoptosis is a form of programmed cell death that is mediated by intrinsic and extrinsic pathways. Dysregulation of and resistance to cell death are hallmarks of cancer. For over three decades, the development of therapies to promote treatment of cancer by inducing various cell death modalities, including apoptosis, has been a main goal of clinical oncology. Apoptosis pathways also interact with other signaling mechanisms, such as the p53 signaling pathway and the integrated stress response (ISR) pathway. In addition to agents directly targeting the intrinsic and extrinsic pathway components, anticancer drugs that target the p53 and ISR signaling pathways are actively being developed. In this Review, we discuss selected and promising anticancer therapies in various stages of development, including drug targets, mechanisms, and resistance to related treatments, focusing especially on B cell lymphoma 2 (BCL-2) inhibitors, TRAIL analogues, DR5 antibodies, and strategies that target p53, mutant p53, and the ISR.

The CD33xCD123xCD70 Multispecific CD3-Engaging DARPin MP0533 Induces Selective T Cell-Mediated Killing of AML Leukemic Stem Cells

The prognosis of patients with acute myeloid leukemia (AML) is limited, especially for elderly or unfit patients not eligible for hematopoietic stem cell (HSC) transplantation. The disease is driven by leukemic stem cells (LSCs), which are characterized by clonal heterogeneity and resistance to conventional therapy. These cells are therefore believed to be a major cause of progression and relapse. We designed MP0533, a multispecific CD3-engaging designed ankyrin repeat protein (DARPin) that can simultaneously bind to three antigens on AML cells (CD33, CD123, and CD70), aiming to enable avidity-driven T cell-mediated killing of AML cells coexpressing at least two of the antigens. In vitro, MP0533 induced selective T cell-mediated killing of AML cell lines, as well as patient-derived AML blasts and LSCs, expressing two or more target antigens, while sparing healthy HSCs, blood, and endothelial cells. The higher selectivity also resulted in markedly lower levels of cytokine release in normal human blood compared to single antigen-targeting T-cell engagers. In xenograft AML mice models, MP0533 induced tumor-localized T-cell activation and cytokine release, leading to complete eradication of the tumors while having no systemic adverse effects. These studies show that the multispecific-targeting strategy used with MP0533 holds promise for improved selectivity toward LSCs and efficacy against clonal heterogeneity, potentially bringing a new therapeutic option to this group of patients with a high unmet need. MP0533 is currently being evaluated in a dose-escalation phase 1 study in patients with relapsed or refractory AML (NCT05673057).

Combination therapy with novel agents for acute myeloid leukaemia: Insights into treatment of a heterogenous disease

The treatment landscape of acute myeloid leukaemia (AML) is evolving rapidly. Venetoclax in combination with intensive chemotherapy or doublets or triplets with targeted or immune therapies is the focus of numerous ongoing trials. The development of mutation-targeted therapies has greatly enhanced the treatment armamentarium, with FLT3 inhibitors and isocitrate dehydrogenase inhibitors improving outcomes in frontline and relapsed/refractory (RR) AML, and menin inhibitors showing efficacy in RR NPM1mut and KMT2A-rearranged AML. With so many new drugs approved, the number of potential combinatorial approaches to leverage the maximal benefit of these agents has increased dramatically, while at the same time introducing clinical challenges, such as key preclinical and clinical data supporting the development of combinatorial therapy, how to optimally combine or sequence these novel agents, how to optimise dose and duration to maintain safety while enhancing efficacy, the optimal duration of therapy and the role of measurable residual disease in decision-making in both intensive and low-intensity therapy settings. In this review, we will outline the evidence leading to the approval of key agents in AML, their on-label current approvals and how they may be optimally combined in a safe and deliverable fashion to further improve outcomes in AML.

Advances in Drug Delivery Systems for the Treatment of Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a common and catastrophic hematological neoplasm with high mortality rates. Conventional therapies, including chemotherapy, hematopoietic stem cell transplantation (HSCT), immune therapy, and targeted agents, have unsatisfactory outcomes for AML patients due to drug toxicity, off-target effects, drug resistance, drug side effects, and AML relapse and refractoriness. These intrinsic limitations of current treatments have promoted the development and application of nanomedicine for more effective and safer leukemia therapy. In this review, the classification of nanoparticles applied in AML therapy, including liposomes, polymersomes, micelles, dendrimers, and inorganic nanoparticles, is reviewed. In addition, various strategies for enhancing therapeutic targetability in nanomedicine, including the use of conjugating ligands, biomimetic-nanotechnology, and bone marrow targeting, which indicates the potential to reverse drug resistance, are discussed. The application of nanomedicine for assisting immunotherapy is also involved. Finally, the advantages and possible challenges of nanomedicine for the transition from the preclinical phase to the clinical phase are discussed.

Outcomes of acute myeloid leukemia patients who responded to venetoclax and azacitidine and stopped treatment

Venetoclax-azacitidine is the standard of treatment for unfit acute myeloid leukemia patients. In the VIALE-A study, treatment was given until progression but there are no data on its optimal duration for responding patients who do not tolerate indefinite therapy. We retrospectively analyzed the outcome of patients who discontinued venetoclax or venetoclax-azacitidine due to poor tolerance. Sixty-two newly diagnosed (ND) AML patients and 22 patients with morphological relapse or refractory AML were included. In the ND cohort (n = 62), 28 patients stopped venetoclax and azacitidine and 34 patients continued azacitidine monotherapy. With a median follow-up of 23 months (IQR, 20-32), median overall survival and treatment-free survival were 44 (IQR, 16-NR) and 16 (IQR, 8-27) months, respectively. Patients who stopped both treatments and those who continued azacitidine monotherapy had the same outcomes. Negative minimal residual disease was associated with a 2-year treatment-free survival of 80%. In the RR cohort (n = 22), median overall survival and treatment-free survival were 19 (IQR, 17-31) and 10 (IQR, 5-NR) months, respectively. Prior number of venetoclax-azacitidine cycles and IDH mutations were associated with increased overall survival. The only factor significantly impacting treatment-free survival was the number of prior cycles. This study suggests that patients who discontinued treatment in remission have favorable outcomes supporting the rationale for prospective controlled trials.

Targeting Molecular Measurable Residual Disease and Low-Blast Relapse in AML With Venetoclax and Low-Dose Cytarabine: A Prospective Phase II Study (VALDAC)

PURPOSE

A prospective phase II study examined the safety and efficacy of venetoclax combined with low-dose cytarabine (LDAC) in AML at first measurable residual disease (MRD) or oligoblastic relapse.

METHODS

Patients with either MRD (≥1 log10 rise) or oligoblastic relapse (blasts 5%-15%) received venetoclax 600 mg once daily D1-28 plus LDAC once daily D1-10 in 28-day cycles. The primary objective was MRD response in the MRD relapse cohort or complete remission (CR/CRh/CRi) in the oligoblastic relapse cohort.

RESULTS

Forty-eight adults with either MRD (n = 26) or oligoblastic (n = 22) relapse were enrolled. Median age was 67 years (range, 18-80) and 94% had received previous intensive chemotherapy. Patients received a median of four cycles of therapy; 17% completed ≥12 cycles. Patients with oligoblastic relapse had more grade ≥3 anemia (32% v 4%; P = .02) and infections (36% v 8%; P = .03), whereas grade 4 neutropenia (32 v 23%) or thrombocytopenia (27 v 15%) were comparable with the MRD relapse cohort. Markers of molecular MRD relapse included mutant NPM1 (77%), CBFB::MYH11 (4%), RUNX1::RUNX1T1 (4%), or KMT2A::MLLT3 (4%). Three patients with a log10 rise in IDH1/2 (12%) were included. By cycle 2 in the MRD relapse cohort, a log10 reduction in MRD was observed in 69%; 46% achieved MRD negative remission. In the oligoblastic relapse cohort, 73% achieved CR/CRh/CRi. Overall, 21 (44%) underwent hematopoietic cell transplantation. Median overall survival (OS) was not reached in either cohort. Estimated 2-year OS rate was 67% (95% CI, 50 to 89) in the MRD and 53% (95% CI, 34 to 84) in the oligoblastic relapse cohorts.

CONCLUSION

For AML in first remission and either MRD or oligoblastic relapse, venetoclax plus LDAC is well tolerated and highly effective.

Venetoclax acts as an immunometabolic modulator to potentiate adoptive NK cell immunotherapy against leukemia

Natural killer (NK) cell-based immunotherapy holds promise for cancer treatment; however, its efficacy remains limited, necessitating the development of alternative strategies. Here, we report that venetoclax, an FDA-approved BCL-2 inhibitor, directly activates NK cells, enhancing their cytotoxicity against acute myeloid leukemia (AML) both in vitro and in vivo, likely independent of BCL-2 inhibition. Through comprehensive approaches, including bulk and single-cell RNA sequencing, avidity measurement, and functional assays, we demonstrate that venetoclax increases the avidity of NK cells to AML cells and promotes lytic granule polarization during immunological synapse (IS) formation. Notably, we identify a distinct CD161lowCD218b+ NK cell subpopulation that exhibits remarkable sensitivity to venetoclax treatment. Furthermore, venetoclax promotes mitochondrial respiration and ATP synthesis via the NF-κB pathway, thereby facilitating IS formation in NK cells. Collectively, our findings establish venetoclax as a multifaceted immunometabolic modulator of NK cell function and provide a promising strategy for augmenting NK cell-based cancer immunotherapy.

Venetoclax therapy and emerging resistance mechanisms in acute myeloid leukaemia

Acute myeloid leukaemia (AML) is a highly aggressive and devastating malignancy of the bone marrow and blood. For decades, intensive chemotherapy has been the frontline treatment for AML but has yielded only poor patient outcomes as exemplified by a 5-year survival rate of < 30%, even in younger adults. As knowledge of the molecular underpinnings of AML has advanced, so too has the development new strategies with potential to improve the treatment of AML patients. To date the most promising of these targeted agents is the BH3-mimetic venetoclax which in combination with standard of care therapies, has manageable non-haematological toxicity and exhibits impressive efficacy. However, approximately 30% of AML patients fail to respond to venetoclax-based regimens and almost all treatment responders eventually relapse. Here, we review the emerging mechanisms of intrinsic and acquired venetoclax resistance in AML and highlight recent efforts to identify novel strategies to overcome resistance to venetoclax.

Patient-Reported Outcomes in Phase 3 Clinical Trials for Blood Cancers: A Systematic Review

Importance

Published research suggests that patient-reported outcomes (PROs) are neither commonly collected nor reported in randomized clinical trials (RCTs) for solid tumors. Little is known about these practices in RCTs for hematological malignant neoplasms.

Objective

To evaluate the prevalence of PROs as prespecified end points in RCTs of hematological malignant neoplasms, and to assess reporting of PROs in associated trial publications.

Evidence Review

All issues of 8 journals known for publishing high-impact RCTs (NEJM, Lancet, Lancet Hematology, Lancet Oncology, Journal of Clinical Oncology, Blood, JAMA, and JAMA Oncology) between January 1, 2018, and December 13, 2022, were searched for primary publications of therapeutic phase 3 trials for adults with hematological malignant neoplasms. Studies that evaluated pretransplant conditioning regimens, graft-vs-host disease treatment, or radiotherapy as experimental treatment were excluded. Data regarding trial characteristics and PROs were extracted from manuscripts and trial protocols. Univariable analyses assessed associations between trial characteristics and PRO collection or reporting.

Findings

Ninety RCTs were eligible for analysis. PROs were an end point in 66 (73%) trials: in 1 trial (1%) as a primary end point, in 50 (56%) as a secondary end point, and in 15 (17%) as an exploratory end point. PRO data were reported in 26 of 66 primary publications (39%): outcomes were unchanged in 18 and improved in 8, with none reporting worse PROs with experimental treatment. Trials sponsored by for-profit entities were more likely to include PROs as an end point (49 of 55 [89%] vs 17 of 35 [49%]; P < .001) but were not significantly more likely to report PRO data (20 of 49 [41%] vs 6 of 17 [35%]; P = .69). Compared with trials involving lymphoma (18 of 29 [62%]) or leukemia or myelodysplastic syndrome (18 of 28 [64%]), those involving plasma cell disorders or multiple myeloma (27 of 30 [90%]) or myeloproliferative neoplasms (3 of 3 [100%]) were more likely to include PROs as an end point (P = .03). Similarly, compared with trials involving lymphoma (3 of 18 [17%]) or leukemia or myelodysplastic syndrome (5 of 18 [28%]), those involving plasma cell disorders or multiple myeloma (16 of 27 [59%]) or myeloproliferative neoplasms (2 of 3 [67%]) were more likely to report PROs in the primary publication (P = .01).

Conclusions and Relevance

In this systematic review, almost 3 of every 4 therapeutic RCTs for blood cancers collected PRO data; however, only 1 RCT included PROs as a primary end point. Moreover, most did not report resulting PRO data in the primary publication and when reported, PROs were either better or unchanged, raising concern for publication bias. This analysis suggests a critical gap in dissemination of data on the lived experiences of patients enrolled in RCTs for hematological malignant neoplasms.

Treatment of Myelodysplastic Syndromes for Older Patients: Current State of Science, Challenges, and Opportunities

PURPOSE OF REVIEW

Myelodysplastic syndromes/neoplasms (MDS) represent a diverse group of pathologically distinct diseases with varying prognoses and risks of leukemia progression. This review aims to discuss current treatment options for elderly patients with MDS, focusing on patients ineligible for intensive chemotherapy or allogenic hematopoietic stem cell transplantation (HSCT). The challenges associated with treatment in this population and emerging therapeutic prospects are also explored.

RECENT FINDINGS

Recent advancements in molecular diagnostics have enhanced risk stratification by incorporating genetic mutations, notably through the molecular International Prognostic Scoring System (IPSS-M). Lower-risk MDS (LR-MDS) treatment ranges from observation to supportive measures and erythropoiesis-stimulating agents (ESAs), with emerging therapies like luspatercept showing promise. High-risk MDS (HR-MDS) is treated with hypomethylating agents (HMAs) or allogenic HSCT, but outcomes remain poor. Elderly MDS patients, often diagnosed after 70, pose challenges in treatment decision-making. The IPSS-M aids risk stratification, guiding therapeutic choices. For LR-MDS, supportive care, ESAs, and novel agents like luspatercept are considered. Treatment of HR-MDS involves HMAs or allogenic HSCT. Emerging treatments, including oral HMAs and novel agents targeting FLT3, and IDH 1/2 mutations, show promise. Future research should refine treatment strategies for this elderly population focusing on quality-of-life improvement.

Metronomic chemotherapy in hematology: Lessons from preclinical and clinical studies to build a solid rationale for future schedules

Metronomic chemotherapy (mCHEMO), based on frequent, regular administration of low, but pharmacologically active drug doses, optimizes antitumor efficacy by targeting multiple targets and reducing toxicity of antineoplastic drugs. This minireview will summarize preclinical and clinical studies on cytotoxic drugs given at weekly, daily, or at continuous metronomic schedules alone or in combination with novel targeted agents for hematological malignancies, including lymphoma, multiple myeloma, and leukemia. Most of the preclinical in vitro and in vivo studies have reported a significant benefit of both mCHEMO monotherapy and combinatorial regimens compared with chemotherapy at the maximum tolerated dose. However, the combination of mCHEMO with targeted drugs is still little explored in the hematologic clinical setting. Data obtained from preclinical studies on low dose metronomic chemotherapy in hematological malignancies clearly suggested the possibility to clinically investigate more tolerable and effective strategies for the treatment of patients with advanced hematological malignancies, or at least for those frail and elderly patients, who are not eligible or resistant to standard treatments.

Comparison of venetoclax and ivosidenib/enasidenib for unfit newly diagnosed patients with acute myeloid leukemia and IDH1/2 mutation: a network meta-analysis

Because of lacking of head-to-head comparison between venetoclax and IDH1/IDH2 inhibitors (ivosidenib/enasidenib) for newly diagnosed unfit patients with acute myeloid leukemia (AML), the optimal option for these patients still remains undefined. We searched relevant published reports. Three RCTs with 180 IDH1 mutant and 165 IDH2 mutant patients were identified. Indirect comparison of OS using fixed effects network meta-analysis (NMA) models indicated venetoclax plus azacitidine (Ven-Aza) significantly improved survival than enasidenib plus azacitidine (Ena-Aza) (HR:0.30, p = 0.005) for those newly diagnosed patients with AML and IDH2 Mutation. And, for those IDH2 mutation patients, Ven-Aza also had the highest probability of 98.3% (OS analysis) and 84.0% (CR/CRi analysis) to be the best intervention among these first-line treatment regimens (Ven-Aza, Ena-Aza and Aza). And, there was a favorable trend towards Ven-Aza in survival analysis (HR:0.69, p = 0.42), when compared to ivosidenib plus azacitidine (Ivo-Aza) for those newly diagnosed patients with AML and IDH1 Mutation. For those IDH1 Mutation, venetoclax plus azacitidine (Ven-Aza) had the highest probability of 65.8% (OS analysis) and 73.0% (CR/CRi analysis) to be the best intervention among these first-line treatment regimens (Ven-Aza, ivosidenib plus azacitidine (Ivo-Aza) and azacitidine (Aza)). In conclusion, venetoclax plus azacitidine could be a good option for unfit newly diagnosed patients with acute myeloid leukemia and IDH1/2 mutation. Considering our limits (only trial data-based network meta-analysis et al.), future trials directly comparing these regimens are warranted.

Venetoclax plus cytarabine and azacitidine in relapsed/refractory AML: An open-label, single-arm, phase 2 study

BACKGROUND

The outcome of relapsed/refractory (R/R) acute myeloid leukemia (AML) remains extremely poor. Venetoclax (VEN)-based regimens have shown promise in treating R/R AML.

OBJECTIVE

This phase 2 study aimed to systematically evaluate the efficacy and safety of the VAA regimen (VEN plus Cytarabine and Azacitidine) in R/R AML patients.

METHODS

Thirty R/R AML patients were enrolled. The study adopted a stepwise ramp-up of VEN dosing, starting with 100 mg on day 1, escalating to 200 mg on day 2, and reaching 400 mg from day 3 to day 9. Cytarabine (10 mg/m2, q12h) was administered intravenously twice daily from days 1 to 10, and Azacitidine (75 mg/m2) was administered via subcutaneous injection once daily from days 1-7. The primary efficacy endpoint was the composite complete remission rate (CRc), including complete response (CR) and complete response with incomplete blood count recovery (CRi). Secondary endpoints included overall survival (OS), duration of response (DOR), and safety analysis.

RESULTS

The CRc rate was 63.3% (19/30), with CR in 36.7% of patients and CRi in 26.7%. Notably, 14 (73.7%) of 19 patients achieving CRc showed undetectable measurable residual disease by flow cytometry. With a median follow-up of 10.7 months, the median OS had not been reached, and the median DOR was 18.3 months. The most common grade 3-4 adverse events (AEs) were neutropenia (100%), anemia (96.7%), thrombocytopenia (90.0%), and leukopenia (90.0%). Infections, with pneumonia being the most prevalent (43.3%), were observed, including one fatal case of Pseudomonas aeruginosa septicemia. There were no treatment-related deaths.

CONCLUSION

The VAA regimen is an effective and safe option for patients with R/R AML, demonstrating a high CRc rate and manageable safety profile.

BCL-2 inhibition in haematological malignancies: Clinical application and complications

B-cell lymphoma-2 (BCL-2) family proteins are fundamental regulators of the intrinsic apoptotic pathway which modulate cellular fate. In many haematological malignancies, overexpression of anti-apoptotic factors (BCL-2, BCL-XL and MCL-1) circumvent apoptosis. To address this cancer hallmark, a concerted effort has been made to induce apoptosis by inhibiting BCL-2 family proteins. A series of highly selective BCL-2 homology 3 (BH3) domain mimetics are in clinical use and in ongoing clinical trials for acute myeloid leukaemia (AML), chronic myeloid leukaemia (CML), chronic lymphocytic leukaemia (CLL), and multiple myeloma (MM). These inhibitors serve as promising candidates, both as single agents or in combination therapy to improve patient outcomes. In other diseases such as follicular lymphoma, efficacy has been notably limited. There are also clinical problems with BCL-2 family inhibition, including drug resistance, disease relapse, tumour lysis syndrome, and clinically relevant cytopenias. Here, we provide a balanced view on both the clinical benefits of BCL-2 inhibition as well as the associated challenges.

Pracinostat combined with azacitidine in newly diagnosed adult acute myeloid leukemia (AML) patients unfit for standard induction chemotherapy: PRIMULA phase III study

Non-intensive therapies such as the hypomethylating agent (HMA) azacitidine (AZA) have been used in patients with AML ineligible for intensive induction chemotherapy (IC) or stem cell transplant due to advanced age, comorbidities, and/or risk factors. However, response rates and survival remain dismal. Pre-clinical studies indicate the epigenetic combination of HMAs and HDAC inhibitors induce re-expression of silenced genes synergistically. The activity of pracinostat, an oral pan-HDAC inhibitor, has been shown in xenograft tumor models of AML and promising efficacy was seen in a Phase 2 study. This Phase 3 study (NCT03151408) evaluated the efficacy/safety of pracinostat administered with AZA in adult patients with newly diagnosed AML ineligible to receive IC. Patients were randomized to either pracinostat plus AZA or placebo/AZA and stratified by cytogenetic risk and ECOG status. As planned, an interim analysis was performed when 232/390 events (deaths) occurred. A total of 406 patients were randomized (203/group) at the time of the analysis. Median overall survival was 9.95 months for both treatment groups (p=0.8275). There was no significant difference between treatments in secondary efficacy endpoints, reflecting a lack of clinical response. This study did not show a benefit of adding pracinostat to AZA in elderly patients unfit for IC.

Management of isocitrate dehydrogenase 1/2 mutated acute myeloid leukemia

The emergence of next generation sequencing and widespread use of mutational profiling in acute myeloid leukemia (AML) has broadened our understanding of the heterogeneous molecular basis of the disease. Since genetic sequencing has become a standard practice, several driver mutations have been identified. Accordingly, novel targeted therapeutic agents have been developed and are now approved for the treatment of subsets of patients that carry mutations in FLT3, IDH1, and IDH2 [1, 2]. The emergence of these novel agents in AML offers patients a new modality of therapy, and shifts treatment paradigms toward individualized medicine. In this review, we outline the role of IDH mutations in malignant transformation, focus in on a novel group of targeted therapeutic agents directed toward IDH1- and IDH2-mutant AML, and explore their impact on prognosis in patients with AML.

Venetoclax-Related Neutropenia in Leukemic Patients: A Comprehensive Review of the Underlying Causes, Risk Factors, and Management

Venetoclax is a Bcl-2 homology domain 3 (BH3) mimetic currently approved for the treatment of chronic lymphocytic leukemia (CLL) and acute myeloid leukemia (AML) that has proven to be highly effective in reinstating apoptosis in leukemic cells through the highly selective inhibition of the anti-apoptotic protein B-cell lymphoma-2 (Bcl-2). Clinically, venetoclax has provided lasting remissions through the inhibition of CLL and AML blasts. However, this activity has often come at the cost of grade III/IV neutropenia due to hematopoietic cells' dependence on Bcl-2 for survival. As life-threatening infections are an important complication in these patients, an effective management of neutropenia is indispensable to maximize patient outcomes. While there is general consensus over dose reduction and scheduling modifications to minimize the risk of neutropenia, the impact of these modifications on survival is uncertain. Moreover, guidelines do not yet adequately account for patient-specific and disease-specific risk factors that may predict toxicity, or the role combination treatment plays in exacerbating neutropenia. The objective of this review is to discuss the venetoclax-induced mechanism of hematological toxicity, the potential predictive risk factors that affect patient vulnerability to neutropenia, and the current consensus on practices for management of neutropenia.

Licochalcone A induces mitochondria-dependent apoptosis and interacts with venetoclax in acute myeloid leukemia

The management of patients with acute myeloid leukemia (AML) remains a challenge because of the complexity and heterogeneity of this malignancy. Despite the recent approval of several novel targeted drugs, resistance seems inevitable, and clinical outcomes are still suboptimal. Increasing evidence supports the use of natural plants as an important source of anti-leukemic therapeutics. Licochalcone A (LCA) is an active flavonoid isolated from the roots of licorice, Glycyrrhiza uralensis Fisch., possessing extensive anti-tumor activities. However, its effects on AML and the underlying mechanisms remain unknown. Here, we showed that LCA decreased the viability of established human AML cell lines in a dose- and time-dependent manner. LCA significantly induced mitochondrial apoptotic cell death, accompanied by the downregulation of MCL-1, upregulation of BIM, truncation of BID, and cleavage of PARP. A prominent decline in the phosphorylation of multiple critical molecules, including AKT, glycogen synthase kinase-3β (GSK3β), ERK, and P38 was observed upon LCA treatment, indicating PI3K and MAPK signals were suppressed. Both transcription and translation of c-Myc were also inhibited by LCA. In addition, LCA enhanced the cytotoxicity of the BCL-2 inhibitor venetoclax. Furthermore, the anti-survival and pro-apoptotic effects were confirmed in primary blasts from 10 patients with de novo AML. Thus, our results expand the applications of LCA, which can be regarded as a valuable agent in treating AML.

Venetoclax resistance in acute myeloid leukaemia-Clinical and biological insights

Venetoclax, an oral BCL-2 inhibitor, has been widely incorporated in the treatment of acute myeloid leukaemia. The combination of hypomethylating agents and venetoclax is the current standard of care for elderly and patient's ineligible for aggressive therapies. However, venetoclax is being increasingly used with aggressive chemotherapy regimens both in the front line and in the relapse setting. Our growing experience and intensive research demonstrate that certain genetic abnormalities are associated with venetoclax sensitivity, while others with resistance, and that resistance can emerge during treatment leading to disease relapse. In the current review, we provide a summary of the known mechanisms of venetoclax cytotoxicity, both regarding the inhibition of BCL-2-mediated apoptosis and its effect on cell metabolism. We describe how these pathways are linked to venetoclax resistance and are associated with specific mutations. Finally, we provide the rationale for novel drug combinations in current and future clinical trials.

Simultaneous occurrence of multiple myeloma and acute myeloid leukemia: Case report and literature review

Multiple myeloma (MM) and acute myeloid leukemia (AML) are malignant clonal diseases of cells in different lineages. It remains very rare to have both diseases at first diagnosis. Only 24 cases of this situation were reported from 1971 to 2021, and poor prognosis in most cases. However, here we describe a case of de novo MM and AML occurring simultaneously in a 65-year-old woman. We have successfully used individualized treatment regimens to allow the patient to survive 1.5 years to date, which has exceeded 80 % of statistical cases.

TP53-mutated acute myeloid leukemia and myelodysplastic syndrome: biology, treatment challenges, and upcoming approaches

Improved understanding of TP53 biology and the clinicopathological features of TP53-mutated myeloid neoplasms has led to the recognition of TP53-mutated acute myeloid leukemia/myelodysplastic syndrome (TP53m AML/MDS) as a unique entity, characterized by dismal outcomes following conventional therapies. Several clinical trials have investigated combinations of emerging therapies for these patients with the poorest molecular prognosis among myeloid neoplasms. Although some emerging therapies have shown improvement in overall response rates, this has not translated into better overall survival, hence the notion that p53 remains an elusive target. New therapeutic strategies, including novel targeted therapies, immune checkpoint inhibitors, and monoclonal antibodies, represent a shift away from cytotoxic and hypomethylating-based therapies, towards approaches combining non-immune and novel immune therapeutic strategies. The triple combination of azacitidine and venetoclax with either magrolimab or eprenetapopt have demonstrated safety in early trials, with phase III trials currently underway, and promising interim clinical results. This review compiles background on TP53 biology, available and emerging therapies along with their mechanisms of action for the TP53m disease entity, current treatment challenges, and recently published data and status of ongoing clinical trials for TP53m AML/MDS.

Venetoclax and hypomethylating agents in critically ill patients with newly diagnosed acute myeloid leukaemia

Venetoclax (VEN) in combination with hypomethylating agents (HMAs) is considered the standard of treatment for individuals with newly diagnosed acute myeloid leukaemia (AML) who are ineligible for intensive chemotherapy. We conducted a retrospective analysis that encompassed 16 critically ill patients newly diagnosed with AML who were admitted to the intensive care unit (ICU) and received the VEN and HMA regimen. Among them, 13 were primary AML, and three were MDS-transformed AML. The mean Acute Physiology and Chronic Health Evaluation II (APACHE II) score was 18.9, and the mean sepsis-related organ failure assessment score (SOFA) was 6.2. The average length of the ICU stay was 27.3 days. The median duration of VEN administration was 16 days. After the first course of VEN + HMA, 12 cases (75%) achieved complete remission (CR) or CR with incomplete haematological recovery (CRi). Among the five patients harbouring TP53 mutations, the overall response rate (ORR) was 90%. All patients experienced grade 3-4 haematological adverse events (AEs). With a median follow-up of 9.5 months (range: 0.5-23), the overall survival (OS) rate was 43.75%. TP53-wild patients and CR state after the first course of VEN-HMA indicated better survival. The combination of VEN and HMA has demonstrated a significantly elevated therapeutic response rate in newly diagnosed AML patients with critical illness.

Venetoclax Combination Treatment of Acute Myeloid Leukemia in Adolescents and Young Adult Patients

Over the past two decades, the prognosis in adolescents and young adults (AYAs) diagnosed with acute myeloid leukemia (AML) has significantly improved. The standard intensive cytotoxic treatment approach for AYAs with AML, consisting of induction chemotherapy with anthracycline/cytarabine combination followed by consolidation chemotherapy or stem cell transplantation, has lately been shifting toward novel targeted therapies, mostly in the fields of clinical trials. One of the most recent advances in treating AML is the combination of the B-cell lymphoma 2 (Bcl-2) inhibitor venetoclax with hypomethylating agents, which has been studied in elderly populations and was approved by the Food and Drug Administration (FDA) for patients over 75 years of age or patients excluded from intensive chemotherapy induction schemas due to comorbidities. Regarding the AYA population, venetoclax combination therapy could be a therapeutic option for patients with refractory/relapsed (R/R) AML, although data from real-world studies are currently limited. Venetoclax is frequently used by AYAs diagnosed with advanced hematologic malignancies, mainly acute lymphoblastic leukemia and myelodysplastic syndromes, as a salvage therapeutic option with considerable efficacy and safety. Herein, we aim to summarize the evidence obtained from clinical trials and observational studies on venetoclax use in AYAs with AML. Based on the available evidence, venetoclax is a safe and effective therapeutic option for R/R AML AYA patients. However, further research in larger cohorts is needed to confirm these data, establishing the benefits of a venetoclax-based regimen for this special population.

AMPK inhibition sensitizes acute leukemia cells to BH3 mimetic-induced cell death

BH3 mimetics, including the BCL2/BCLXL/BCLw inhibitor navitoclax and MCL1 inhibitors S64315 and tapotoclax, have undergone clinical testing for a variety of neoplasms. Because of toxicities, including thrombocytopenia after BCLXL inhibition as well as hematopoietic, hepatic and possible cardiac toxicities after MCL1 inhibition, there is substantial interest in finding agents that can safely sensitize neoplastic cells to these BH3 mimetics. Building on the observation that BH3 mimetic monotherapy induces AMP kinase (AMPK) activation in multiple acute leukemia cell lines, we report that the AMPK inhibitors (AMPKis) dorsomorphin and BAY-3827 sensitize these cells to navitoclax or MCL1 inhibitors. Cell fractionation and phosphoproteomic analyses suggest that sensitization by dorsomorphin involves dephosphorylation of the proapoptotic BCL2 family member BAD at Ser75 and Ser99, leading BAD to translocate to mitochondria and inhibit BCLXL. Consistent with these results, BAD knockout or mutation to BAD S75E/S99E abolishes the sensitizing effects of dorsomorphin. Conversely, dorsomorphin synergizes with navitoclax or the MCL1 inhibitor S63845 to induce cell death in primary acute leukemia samples ex vivo and increases the antitumor effects of navitoclax or S63845 in several xenograft models in vivo with little or no increase in toxicity in normal tissues. These results suggest that AMPK inhibition can sensitize acute leukemia to multiple BH3 mimetics, potentially allowing administration of lower doses while inducing similar antineoplastic effects.

Prognostic impact of peripheral blood WT1 mRNA dynamics in patients with acute myeloid leukemia treated with venetoclax combination therapy

BACKGROUND

Wilms' tumor gene 1 (WT1) mRNA quantification is a useful marker of measurable residual disease in acute myeloid leukemia (AML). However, whether monitoring the WT1 mRNA levels may predict the outcome of venetoclax (VEN) combination therapy in AML is not reported. This study aims to elucidate whether WT1 mRNA dynamics could predict long-term prognosis.

METHODS

33 patients with untreated or relapsed/refractory AML evaluated for peripheral blood WT1 dynamics in VEN combination therapy were analyzed.

RESULTS

The median age was 73 years (range 39-87). Azacitidine was combined with VEN in 91% of patients. Overall, the median overall survival (OS) was 334 days (95% CI 210-482), and the complete remission (CR) plus CR with incomplete hematologic recovery rate was 59%. A 1-log reduction of WT1 mRNA values by the end of cycle 2 of treatment was associated with significantly better OS and event-free survival (EFS) (median OS 482 days vs. 237 days, p = 0.049; median EFS 270 days vs. 125 days, p = 0.02). The negativity of post-treatment WT1 mRNA value during the treatment was associated with significantly better OS and EFS (median OS 482 days vs. 256 days, p = 0.02; median EFS not reached vs. 150 days, p = 0.005). Multivariate analysis confirmed the significance of these two parameters as strong EFS predictors (HR 0.26, p = 0.024 and HR 0.15, p = 0.013, respectively). The increase in WT1 mRNA values was correlated with relapse.

CONCLUSION

This study demonstrates that WT1 mRNA dynamics can be a useful marker for assessing long-term prognosis of VEN combination therapy for AML.

Advancements and Challenges in the Treatment of AML

The therapeutic arsenal for the management of AML has expanded significantly in recent years. Before 2017, newly diagnosed AML was treated with either standard cytarabine- and anthracycline-based induction chemotherapy (for all fit patients) or a single-agent hypomethylating agent (in unfit patients or those 75 years and older). While assessing patient fitness remains important, characterizing the disease biology has become critical to select the optimal initial therapy for each patient with more options available. FLT3 inhibitors, gemtuzumab ozogamicin, and CPX-351 have been shown to improve outcomes for specific subsets of patients. Venetoclax (VEN) with a hypomethylating agent (HMA) is the standard-of-care frontline regimen for most older patients, except perhaps for those with an IDH1 mutation where ivosidenib with azacitidine may also be considered. On the basis of the success seen with HMA/VEN in older patients, there is now increasing interest in incorporating VEN into frontline regimens in younger patients, with promising data from multiple early phase studies. This article focuses on recent updates and ongoing challenges in the management of AML, with a particular focus on the ongoing challenge of secondary AML and considerations regarding the selection of initial therapy in younger patients. An overview of common side effects and toxicities associated with targeted therapies is also presented here, along with recommended strategies to mitigate these risks.

Glasdegib with intensive/nonintensive chemotherapy in Japanese patients with untreated acute myeloid leukemia or high-risk myelodysplastic syndromes

Glasdegib is a potent, selective, oral inhibitor of the hedgehog signaling pathway. In this phase I study, previously untreated Japanese patients with acute myeloid leukemia (AML) or high-risk myelodysplastic syndromes were treated with glasdegib (100 mg once daily) combinations: low-dose cytarabine (20 mg twice daily; cohort 1, n = 6; expansion cohort, n = 15); daunorubicin and cytarabine (60 mg/m2 i.v.; cohort 2, n = 6); or azacitidine (100 mg/m2 i.v.; cohort 3, n = 6). Patients, except cohort 2, were ineligible for intensive chemotherapy. The primary end-point was dose-limiting toxicity in cohorts 1-3 and disease-modifying response in the expansion cohort. Disease-modifying response rate was tested with the null hypothesis of 6.8%, which was set based on the results from the phase II BRIGHT AML 1003 study (NCT01546038). No dose-limiting toxicities were observed in cohorts 1 or 3; one patient in cohort 2 experienced a dose-limiting toxicity of grade 3 erythroderma. The most common grade ≥3 treatment-related adverse events were neutropenia and thrombocytopenia (66.7% each) in cohort 1 and thrombocytopenia (60.0%) in the expansion cohort. In the expansion cohort, the disease-modifying response rate was 46.7% (90% confidence interval, 24.4-70.0; p < 0.0001), with all patients achieving either a complete response or complete response with incomplete blood count recovery. Median overall survival was 13.9 months. In this study, the primary disease-modifying response end-point with glasdegib plus low-dose cytarabine was met. The study confirms the safety and efficacy of glasdegib plus low-dose cytarabine in Japanese patients with AML ineligible for intensive chemotherapy.

Myelomonocytic and monocytic acute myeloid leukemia demonstrate comparable poor outcomes with venetoclax-based treatment: a monocentric real-world study

Venetoclax (VEN), a BCL-2 inhibitor, has transformed treatment strategies for elderly and unfit acute myeloid leukemia (AML) patients by significantly improving response rates and survival. However, the predictive factors for VEN efficacy differ from traditional chemotherapy. The clinical relevance of the FAB (French-American-British) monocytic subtype, including M4 and M5, has been debated as a marker for VEN resistance. This real-world study examined 162 newly diagnosed (ND) and 85 relapsed/refractory (R/R) AML patients who received VEN-based therapy at West China Hospital, Sichuan University, from January 2019 to January 2023. We retrospectively collected clinical and treatment data from electronic medical records. The median age of the cohort was 55.5 years (range: 16.5-83.5). The composite complete remission (cCR) rate in the entire cohort was 60.7%. Specifically, among newly diagnosed (ND) patients, FAB monocytic subtypes exhibited lower cCR compared to non-monocytic subtypes (55.1% vs. 76.3%, P = 0.007). Additionally, there were no significant differences observed between M4 and M5 subtypes, both in the ND group (61.7% vs. 40.9%, p = 0.17) and the R/R group (38.2% vs. 40%, p > 0.9). Furthermore, the median follow-up was 238 (range: 7-1120) days. ND patients with monocytic subtypes had shorter overall survival compared to non-monocytic subtypes (295 days vs. not reached, p = 0.0017). Conversely, R/R patients showed no such difference (204 vs. 266 days, p = 0.72). In summary, our study suggests that the FAB monocytic subtype can predict VEN resistance and shorter survival in ND AML patients. Moreover, there is no significant distinction between M4 and M5 subtypes.

Reduced dose azacitidine plus venetoclax as maintenance therapy in acute myeloid leukaemia following intensive or low-intensity induction: a single-centre, single-arm, phase 2 trial

BACKGROUND

Patients with acute myeloid leukaemia have high rates of relapse, especially if they are unable to complete standard consolidation strategies or allogeneic haematopoietic stem-cell transplantation (HSCT). The phase 3 QUAZAR AML-001 study showed an overall survival benefit with oral azacitidine maintenance. The BCL2 inhibitor venetoclax is highly active in acute myeloid leukaemia and synergistic with azacitidine. We aimed to evaluate the efficacy and safety of low dose azacitidine plus venetoclax as maintenance therapy in acute myeloid leukaemia.

METHODS

We performed a single-centre, single-arm, phase 2 study at the University of Texas MD Anderson Cancer Center in the USA. Eligible patients were adults (aged ≥18 years) with a WHO 2016 diagnosis of acute myeloid leukaemia in complete remission or complete remission with incomplete blood count recovery following intensive or low-intensity induction and not immediately eligible for HSCT. Eastern Cooperative Oncology Group performance status had to be 3 or less. Patients were assigned to maintenance therapy with azacitidine 50 mg/m2 intravenously or subcutaneously for 5 days and venetoclax 400 mg orally for 7 days or 14 days. The primary outcome was relapse-free survival. The study was closed early due to slow accrual. All patients were included in the efficacy and safety analyses. This trial is registered with ClinicalTrials.gov (NCT04062266).

FINDINGS

Between Sept 26, 2019, and Oct 26, 2022, 35 patients were enrolled, of whom 25 (71%) were assigned to cohort 1 following intensive induction and ten (29%) to cohort 2 following low-intensity induction. Of 35 patients, 18 (51%) were male and 17 (49%) were female. The median age was 55 years (IQR 41-62). The median number of cycles given was 9 (IQR 2-22) and median follow-up time was 23·3 months (IQR 9·0-30·0). The median relapse-free survival was not reached (95% CI 20·2 to not calculable) in the full cohort, not reached (29·1 to not calculable) in cohort 1, and 30·3 months (16·5 to not calculable) in cohort 2. The 2-year relapse-free survival was 65% (95% CI 50-85) in the full cohort, 71% (53-94) in cohort 1, and 52% (27-100) in cohort 2. The most common grade 3-4 treatment-emergent adverse events were thrombocytopenia (n=6), lung infection (n=4), leukopenia (n=4), and neutropenia (n=3). No deaths occurred during maintenance therapy.

INTERPRETATION

Low dose azacitidine plus venetoclax is a feasible maintenance strategy in acute myeloid leukaemia following intensive and low-intensity induction.

FUNDING

University of Texas MD Anderson Cancer Center, MDS/AML Moon Shot, Genentech.

Novel Therapeutic Targets in Acute Myeloid Leukemia (AML)

PURPOSE OF REVIEW

This review seeks to identify and describe novel genetic and protein targets and their associated therapeutics currently being used or studied in the treatment of acute myeloid leukemia (AML).

RECENT FINDINGS

Over the course of the last 5-6 years, several targeted therapies have been approved by the FDA, for the treatment of both newly diagnosed as well as relapsed/refractory AML. These novel therapeutics, as well as several others currently under investigation, have demonstrated activity in AML and have improved outcomes for many patients. Patient outcomes in AML have slowly improved over time, though for many patients, particularly elderly patients or those with relapsed/refractory disease, mortality remains very high. With the identification of several molecular/genetic drivers and protein targets and development of therapeutics which leverage those mechanisms to target leukemic cells, outcomes for patients with AML have improved and continue to improve significantly.

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

BACKGROUND

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.

METHODS

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.

FINDINGS

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.

INTERPRETATION

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.

FUNDING

MD Anderson Cancer Center Support Grant, Myelodysplastic Syndrome/Acute Myeloid Leukaemia Moon Shot, Leukemia SPORE, Taiho Oncology, and Astex Pharmaceuticals.

Venetoclax combined chemotherapy versus chemotherapy alone for acute myeloid leukemia: a systematic review and meta-analysis

Objective

To compare the efficacy and safety of venetoclax (VEN) in combination with chemotherapy (chemo) versus chemo alone in the treatment of acute myeloid leukemia (AML).

Method

To compare the efficacy and/or safety of VEN+chemo versus chemotherapy alone for AML, PubMed, Embase, Web of Science, and the Cochrane Library were used to searching up to June 2023. Comparisons included complete remission (CR), CR with incomplete hematologic recovery (CRi), morphologic leukemia-free state (MLFS), overall response rate (ORR), and adverse events (AEs).

Result

A total of 9 articles were included, including 3124 patients. The baseline characteristics between two patient groups were similar. The combined analysis showed that compared with the group receiving chemo alone, the VEN+chemo group exhibited higher rates of CR, CRi, MLFS and ORR. Additionally, the VEN+chemo group had longer event-free survival (EFS) and overall survival (OS) durations. The incidence rates of AEs and serious AEs (SAEs) were similar between the two groups, but the early 30-day mortality rate was lower in the VEN+chemo group than in the chemo alone group.

Conclusion

The VEN+chemo therapy demonstrates significant efficacy and safety profile in AML patients. However, more prospective studies are needed in the future to provide more accurate and robust evidence for treatment selection in patients.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023439288, identifier CRD42023439288.

SOHO State of the Art Updates and Next Questions: Pre-emptive Therapy at Molecular Measurable Residual Disease Failure in Acute Myeloid Leukemia

Molecular measurable residual disease (MRD, eg, by real-time quantitative polymerase chain reaction, RT-qPCR), is an integral part of response assessment in acute myeloid leukemia (AML) with established prognostic and evolving therapeutic significance. MRD failure can occur through several pathways (namely MRD persistence at the end of treatment at a high level, MRD progression from a low level or MRD re-emergence during follow up; the latter two constitute MRD relapse as defined by the European Leukemia Net) and is clinically actionable, with survival benefit reported in AML subgroups. Selection of pre-emptive therapy at MRD failure relies upon an integrated clinico-molecular assessment and is subset-specific. In acute promyelocytic leukemia, arsenic trioxide-based regimen for MRD failure following frontline treatment with all-trans-retinoic acid plus chemotherapy represents standard of care, while hypomethylating agents (eg, azacitidine), salvage chemotherapy (eg, FLAG-IDA) and venetoclax-based regimens are effective in NPM1-mutated AML. Specific inhibitors of FLT3 have emerging use in FLT3-mutated AML and are associated with minimal toxicity. Furthermore, immunotherapeutic approaches such as donor lymphocyte infusions and interferon-⍺ are efficacious options in the post-allogeneic-HSCT settings. Enrollment into clinical trials with genomic-guided assignment of pre-emptive therapy at MRD failure should be prioritized. Finally, with the emergence of novel agents (eg, menin inhibitors) and approaches (eg, adoptive cellular and immunological therapy), an exciting future lies ahead where a broad array of highly active pre-emptive therapeutic options will likely be clinically applicable to a wide range of AML subsets.

How comparable are patient outcomes in the "real-world" with populations studied in pivotal AML trials?

Despite an increasing desire to use historical cohorts as "synthetic" controls for new drug evaluation, limited data exist regarding the comparability of real-world outcomes to those in clinical trials. Governmental cancer data often lacks details on treatment, response, and molecular characterization of disease sub-groups. The Australasian Leukaemia and Lymphoma Group National Blood Cancer Registry (ALLG NBCR) includes source information on morphology, cytogenetics, flow cytometry, and molecular features linked to treatment received (including transplantation), response to treatment, relapse, and survival outcome. Using data from 942 AML patients enrolled between 2012-2018, we assessed age and disease-matched control and interventional populations from published randomized trials that led to the registration of midostaurin, gemtuzumab ozogamicin, CPX-351, oral azacitidine, and venetoclax. Our analyses highlight important differences in real-world outcomes compared to clinical trial populations, including variations in anthracycline type, cytarabine intensity and scheduling during consolidation, and the frequency of allogeneic hematopoietic cell transplantation in first remission. Although real-world outcomes were comparable to some published studies, notable differences were apparent in others. If historical datasets were used to assess the impact of novel therapies, this work underscores the need to assess diverse datasets to enable geographic differences in treatment outcomes to be accounted for.