Measurable Residual Disease in High-Risk Acute Myeloid Leukemia

Single-center experience of venetoclax combined with azacitidine in young patients with newly diagnosed acute myeloid leukemia

Background

Medical resources, especially blood products, were in short supply during the COVID-19. Less intensive therapy with hypomethylating agents/venetoclax (VEN) seems an effective treatment option for patients with acute myeloid leukemia (AML).

Objectives

To retrospectively analyze the efficacy and safety of VEN combined with azacitidine (AZA) in young adult patients with newly diagnosed (ND) AML.

Design

This was a retrospective study.

Methods

The clinical data of 25 AML patients treated with the VEN + AZA regimen from January 2021 to December 2023 at our center were collected, compared with a randomized historical study cohort that was administered intensive chemotherapy (IC) from January 2018 to December 2019.

Results

No rate of complete remission/complete remission with incomplete count recovery differences observed between the two arms reached statistical significance. Compared to traditional IC, minimal residual disease (MRD)-negative remission was achieved more quickly in patients treated with VEN + AZA regimens (after cycle 1: 8% in the IC group vs 56% in the VEN group, p = 0.0004; after cycle 2: 16% in the IC group vs 72% in the VEN group, p = 0.0001), especially in those AML patients who had a poor prognosis. The dependency of transfusion of red blood cell (RBC) and platelets during induction treatment was significantly lower in the VEN + AZA group (RBC: p = 0.0269; platelet: p = 0.0054). Compared with the standard IC, the incidence rate of non-hematological adverse events in VEN + AZA group was significantly decreased (infection: 100% vs 20%, p = 0.0001; gastrointestinal side effects: 48% vs 12%, p = 0.0055). The total hospitalization cost of the VEN group was significantly less than that of the IC group (p = 0.0395).

Conclusion

In conclusion, our study indicated that VEN + AZA with a higher MRD-negative remission rate and less toxic appeared to be a therapy option for young patients with ND AML. However, further well-designed studies with larger numbers of patients are needed to confirm the benefits of VEN + AZA in this population.

Cellular automata modelling of leukaemic stem cell dynamics in acute myeloid leukaemia: insights into predictive outcomes and targeted therapies

Acute myeloid leukaemia (AML) is a haematologic malignancy with high relapse rates in both adults and children. Leukaemic stem cells (LSCs) are central to leukaemopoiesis, treatment response and relapse and frequently associated with measurable residual disease (MRD). However, the dynamics of LSCs within the AML microenvironment is not fully understood. This study utilized three-dimensional cellular automata (CA) modelling to simulate LSC behaviour and treatment response under induction chemotherapy. Our study revealed: (i) a correlation between LSC persistence post-induction chemotherapy and risk of AML relapse; (ii) MRD negativity based on LSC count may not reliably predict outcomes, supporting clinical evidence that patients with MRD-negative status can still be at risk of relapse; (iii) prolonged persistence of LSCs post-chemotherapy without disruption of normal haematopoiesis, aligning with clinical observations of dormant AML clones; (iv) early LSC dynamics post-induction chemotherapy, characterized by stochastic behaviours and movement velocities, are insufficient predictors of long-term prognosis; and (v) a distinct spatiotemporal organization of LSCs in later phases post-induction chemotherapy is correlated with long-term outcomes. Our modelling results provide a theoretical and clinical framework for AML research, and future clinical data validation could refine the utility of CA modelling for oncological studies.

Transforming growth factor-β1 and vascular endothelial growth factor levels in senile acute myeloid leukemia and correlation with prognosis

BACKGROUND

Acute myeloid leukemia (AML) is a disease in which immature hematopoietic cells accumulate in the bone marrow and continuously expand, inhibiting hematopoiesis. The treatment and prognosis of this disease have always been unsatisfactory.

AIM

To investigate the correlation between vascular endothelial growth factor (VEGF) and transforming growth factor-β1 (TGFβ1) expression and prognosis in older adults with AML.

METHODS

This study enrolled 80 patients with AML (AML group), including 36 with complete response (AML-CR), 23 with partial response (AML-PR), and 21 with no response (AML-NR). The expression levels of VEGF and TGFβ1 were detected by reverse transcription polymerase chain reaction in bone marrow mononuclear cells isolated from 56 healthy controls. Kaplan-Meier analysis was performed to assess overall survival (OS) and progression- or disease-free survival (DFS). Prognostic risk factors were analyzed using a Cox proportional hazards model.

RESULTS

The AML group showed a VEGF level of 2.68 ± 0.16. VEGF expression was lower in patients with AML-CR than those with AML-PR or AML-NR (P < 0.05). TGFβ1 expression in the AML group was 0.33 ± 0.05. Patients with AML-CR showed a higher TGFβ1 expression than those with AML-PR or AML-NR (P < 0.05). VEGF and TGFβ1 expression in patients with AML was significantly correlated with the counts of leukocytes, platelets, hemoglobin, and peripheral blood immature cells (P < 0.05); Kaplan-Meier survival analysis revealed that patients with high TGFβ1 expression had better OS and DFS than those with low TGFβ1 expression (P < 0.05), whereas patients with low VEGF levels showed better OS and DFS than those with high VEGF levels (P < 0.05). VEGF, TGFβ1, and platelet count were identified by the Cox proportional hazards model as independent risk factors for OS (P < 0.05), while VEGF, TGFβ1, and white blood cell count were independent risk factors for DFS (P < 0.05).

CONCLUSION

Decreased VEGF expression and increased TGFβ1 expression in patients with AML provide valuable references for determining and individualizing clinical treatment strategies.

Minimal Residual Disease in Acute Myeloid Leukemia: Old and New Concepts

Minimal residual disease (MRD) is of major importance in onco-hematology, particularly in acute myeloid leukemia (AML). MRD measures the amount of leukemia cells remaining in a patient after treatment, and is an essential tool for disease monitoring, relapse prognosis, and guiding treatment decisions. Patients with a negative MRD tend to have superior disease-free and overall survival rates. Considerable effort has been made to standardize MRD practices. A variety of techniques, including flow cytometry and molecular methods, are used to assess MRD, each with distinct strengths and weaknesses. MRD is recognized not only as a predictive biomarker, but also as a prognostic tool and marker of treatment efficacy. Expected advances in MRD assessment encompass molecular techniques such as NGS and digital PCR, as well as optimization strategies such as unsupervised flow cytometry analysis and leukemic stem cell monitoring. At present, there is no perfect method for measuring MRD, and significant advances are expected in the future to fully integrate MRD assessment into the management of AML patients.

Combating Acute Myeloid Leukemia via Sphingosine Kinase 1 Inhibitor-Nanomedicine Combination Therapy with Cytarabine or Venetoclax

MP-A08 is a novel sphingosine kinase 1 (SPHK1) inhibitor with activity against acute myeloid leukemia (AML). A rationally designed liposome-based encapsulation and delivery system has been shown to overcome the physicochemical challenges of MP-A08 and enable its effective delivery for improved efficacy and survival of mice engrafted with human AML in preclinical models. To establish therapies that overcome AML's heterogeneous nature, here we explored the combination of MP-A08-loaded liposomes with both the standard chemotherapy, cytarabine, and the targeted therapy, venetoclax, against human AML cell lines. Cytarabine (over the dose range of 0.1-0.5 µM) in combination with MP-A08 liposomes showed significant synergistic effects (as confirmed by the Chou-Talalay Combination Index) against the chemosensitised human AML cell lines MV4-11 and OCI-AML3. Venetoclax (over the dose range of 0.5-250 nM) in combination with MP-A08 liposomes showed significant synergistic effects against the chemosensitised human AML cell lines, particularly in venetoclax-resistant human AML cells. This strong synergistic effect is due to multiple mechanisms of action, i.e., inhibiting MCL-1 through SPHK1 inhibition, leading to ceramide accumulation, activation of protein kinase R, ATF4 upregulation, and NOXA activation, ultimately resulting in MCL-1 degradation. These combination therapies warrant further consideration and investigation in the search for a more comprehensive treatment strategy for AML.

Prognostic value of combined WT1 and multiparameter flow cytometry assessment for measurable residual disease after induction in non-APL acute myeloid leukemia

The objective of this study was to investigate the expression pattern of Wilms tumor 1 (WT1) gene at diagnosis, complete remission (CR) and relapse status in non-acute promyelocytic leukemia (non-APL) acute myeloid leukemia (AML) patients, and further explore the prognostic value of measurable residual disease (MRD) assessment by WT1 gene and multiparameter flow cytometry (MFC). Our results showed that the average expression level of WT1 was 4026 ± 616.1 copies/104 ABL at diagnosis, 155.3 ± 36.03 copies/104 ABL at CR, and 1766 ± 238.8 copies/104 ABL at relapse, with statistically significant differences (p = .000). ROC analysis showed that WT1 expression levels were 118.1 copies/104 ABL and MFC-MRD was 0.155%, which had good predictive efficacy for relapse of patients during consolidation therapy. Both WT1-MRD and MFC-MRD had a significant impact on relapse-free survival (RFS) and overall survival (OS). Patients with WT1-MRD positive or MFC-MRD positive were associated with worse RFS (HR 3.840, 95% CI 1.582-9.320, p = .003), (HR 4.464, 95% CI 1.841-10.984, p = .001) and worse OS (HR 2.963, 95% CI 1.058-8.295, p = .039), (HR 3.590, 95% CI 1.254-10.280, p = .017). Besides, compared with patients who were negative for both WT1-MRD and MFC-MRD, patients who were positive both WT1-MRD and MFC-MRD were associated with worse RFS (HR 6.200, 95% CI 2.206-17.430, p = .001) and worse OS (HR 4.886, 95% CI 1.388-17.197, p = .013). This study demonstrates that combined assessment of MRD by WT1 and MFC improves relapse and prognosis prediction in non-APL AML patients, and may help guide interventions for disease relapse.

Venetoclax plus cyclophosphamide and cytarabine as induction regimen for adult acute myeloid leukemia

Background

The efficacy of induction chemotherapy (IC) for acute myeloid leukemia (AML) has improved significantly with the application of targeting drugs. Our previous study showed that a 4-day IC regimen of cyclophosphamide (CTX) and Ara-C [CA (4 + 3)] achieved similar complete remission (CR) rate (80%) compared with the traditional 7-day regimen, and the survival rate appeared to be better.

Methods

In this pilot study, we further shortened the CA regimen to 3 days, added low-dose venetoclax (VEN, 200 mg/day) (VCA), and reported the efficacy and safety here.

Results

Twenty-five newly diagnosed adult AML patients were enrolled in this study and evaluated for the remission rate after one cycle of the VCA regimen. The CR/Cri was 92%, and all these patients had undetectable minimal residual disease (MRD^-). The estimated overall survival at 12 months was 79.3%. The median time for both platelet recovery and absolute neutrophil count recovery was 16 days, faster than that of traditional IC. Compared with the previous CA (4 + 3) regimen, a higher CR rate (92% vs. 80%, P < 0.01) and a deeper degree of remission (CR_MRD- rate, 92% vs. 45%, P < 0.01) were found in the VCA group.

Conclusions

This study showed that the 3-day CTX and Ara-C regimen is highly effective in newly diagnosed AML patients, and the addition of VEN to the CA regimen achieves higher and deeper one-course remission.

Real-world experience with CPX-351 in high-risk acute myeloid leukemia

CPX-351, a dual-drug liposomal encapsulation of daunorubicin/cytarabine, was approved for newly diagnosed therapy-related acute myeloid leukemia (AML) and AML with myelodysplasia-related changes in adults in 2017 (US; updated to patients aged ≥1 year in 2021) and 2018 (EU/UK) based on improved survival and remission and comparable safety versus 7+3 chemotherapy in a randomized trial in older adults. Real-world studies have since evaluated CPX-351 in routine practice across several countries and addressed important data gaps (e.g., use in younger adults, measurable residual disease negativity, outcomes by mutation). This review discusses real-world studies of CPX-351 as AML treatment, with the aim of helping prescribers make informed treatment decisions.

Oral Antineoplastics in Acute Myeloid Leukemia: A Comprehensive Review

AML is a biologically and clinically heterogeneous disease that is associated with poor overall long-term survival. The expanding knowledge of genomic landscape in AML as well as advancements in molecular and chemical biology over the pathway in AML. After 40 years of stagnancy, the recent approval of numerous novel oral anti-leukemic agents for the treatment of AML has changed both the armamentarium of medications and treatment paradigms. These agents have unique clinical considerations in terms of administration, adverse effects, and monitoring parameters which may differ from clinician's historical expectations. Understanding the data, indication and clinical considerations for such novel oral anti-leukemic agents is paramount for clinicians caring patients with AML.