Outcomes and genetic dynamics of acute myeloid leukemia at first relapse.

Patients with relapsed acute myeloid leukemia (rAML) experience dismal outcomes. We performed a comprehensive analysis of patients with rAML to determine the genetic dynamics and survival predictive factors. We analyzed 875 patients with newly diagnosed AML who received intensive treatment (IT) or low-intensity treatment (LIT). Of these patients, 197 experienced subsequent rAML. Data was available for 164 patients, with a median time from CR/CRi to relapse of 6.5 months. Thirty-five of the 164 patients (21%) experienced relapse after allogeneic hematopoietic stem cell transplantation (alloSCT). At relapse mutations in genes involved in pathway signaling tended to disappear, whereas clonal hematopoiesis-related mutations or TP53 tended to persist. Patients with normal karyotypes tended to acquire cytogenetic abnormalities at relapse. Patients treated with IT had a higher emergence rate of TP53 mutations (16%), compared to patients treated with LIT (1%, P = 0.009). The overall response rates were 38% and 35% for patients treated with salvage IT or LIT, respectively. Seventeen patients (10%) underwent alloSCT after salvage therapy. The median overall survival (OS) duration after relapse was 5.3 months, with a 1-year OS rate of 17.6%. Complex karyotype (hazard ratio [HR] = 2.14, P < 0.001), a KMT2A rearrangement (HR = 3.52, P = 0.011), time in remission < 12 months (HR = 1.71, P = 0.011), and an elevated white blood cell count at relapse (HR = 2.38, P = 0.005) were independent risk factors for OS duration. More effective frontline and maintenance therapies are warranted to prevent rAML.

Advances in the management of higher-risk myelodysplastic syndromes: future prospects.

Higher-risk myelodysplastic syndromes (HR-MDS) are defined using a number of prognostic scoring systems that include the degree of cytopenias, percentage of blasts, cytogenetic alterations, and more recently genomic data. HR-MDS encompasses characteristics such as progressive cytopenias, increased bone marrow blasts, unfavorable cytogenetics, and an adverse mutational profile. Survival is generally poor, and patients require therapy to improve outcomes. Hypomethylating agents (HMAs), such as azacitidine, decitabine, and more recently, oral decitabine/cedazuridine, are the only approved therapies for HR-MDS. These are often continued until loss of response, progression, or unacceptable toxicity. Combinations including an HMA plus other drugs have been investigated but have not demonstrated better outcomes compared to single-agent HMA. Moreover, in a disease of high genomic complexity such as HR-MDS, therapy targeting specific genomic abnormalities is of interest. This review will examine the biological underpinnings of HR-MDS, its therapeutic landscape in the frontline and relapsed settings, as well as the impact of hematopoietic stem cell transplantation, the only known curative intervention for this disease.

Lower intensity therapy with cladribine/low dose cytarabine/venetoclax in older patients with acute myeloid leukemia compares favorably with intensive chemotherapy among patients undergoing allogeneic stem cell transplantation.

BACKGROUND: Allogeneic stem cell transplantation (SCT) remains the best consolidative modality in most patients with acute myeloid leukemia (AML). Along with factors directly pertaining to SCT, pretransplantation disease control, performance status, and prior treatment-related complications are important factors that affect posttransplantation survival outcomes. METHODS: The authors compared the survival outcomes of patients ≥60 years of age treated on the phase 2 clinical trial of venetoclax (Ven) added to cladribine (CLAD) and low dose cytarabine (LDAC) alternating with azacitidine (CLAD/LDAC/Ven arm) (NCT03586609) who underwent allogeneic SCT in first remission to a retrospective cohort of patients ≥60 years of age who underwent SCT after intensive chemotherapy. Intensive chemotherapy was defined as the use of cytarabine >1 g/m2 and anthracyclines during induction/consolidation. RESULTS: Thirty-five patients at median age of 68 years in the CLAD/LDAC/Ven arm were compared to 42 patients at a median age of 62 years in the intensive therapy arm. The 2-year relapse-free survival was superior with CLAD/LDAC/Ven versus intensive chemotherapy (88% vs. 65%; p = .03) whereas the 2-year overall survival (OS) was comparable (84% vs. 70%; p = .14). On a competing event analysis, the 2-year cumulative incidence of relapse (CIR) was significantly lower with CLAD/LDAC/Ven versus intensive chemotherapy (2.9% vs. 17.2%, Gray's p = .049) whereas nonrelapse mortality was comparable (16.2% vs. 17.1%; p = .486). CONCLUSION: In conclusion, treatment with CLAD/LDAC/Ven was associated with favorable outcomes in older patients who underwent subsequent allogeneic SCT. The OS was comparable to that with intensive chemotherapy followed by allogeneic SCT, but the CIR rate was significantly lower.

Therapy-related chronic myelomonocytic leukemia does not have the high-risk features of a therapy-related neoplasm.

ABSTRACT: Therapy-related myeloid neoplasms (t-MNs) arise after exposure to cytotoxic therapies and are associated with high-risk genetic features and poor outcomes. We analyzed a cohort of patients with therapy-related chronic myelomonocytic leukemia (tCMML; n = 71) and compared its features to that of de novo CMML (dnCMML; n = 461). Median time from cytotoxic therapy to tCMML diagnosis was 6.5 years. Compared with dnCMML, chromosome-7 abnormalities (4% vs 13%; P = .005) but not complex karyotype (3% vs 7%; P = .15), were more frequent in tCMML. tCMML was characterized by higher TP53 mutation frequency (4% vs 12%; P = .04) and lower NRAS (6% vs 22%, P = .007) and CBL (4% vs 12%, P = .04) mutation frequency. Prior therapy with antimetabolites (odd ratio [OR], 1.22; 95% confidence interval [CI], 1.05-1.42; P = .01) and mitotic inhibitors (OR, 1.24; 95% CI, 1.06-1.44; P = .009) was associated with NF1 and SETBP1 mutations whereas prior mitotic inhibitor therapy was associated with lower TET2 mutation frequency (OR, 0.71; 95% CI, 0.55-0.92; P = .01). Although no differences in median overall survival (OS) were observed among tCMML and dnCMML (34.7 months vs 35.9 months, P = .26), multivariate analysis for OS revealed that prior chemotherapy was associated with increased risk of death (hazard ratio, 1.76; 95% CI, 1.07-2.89; P = .026). Compared with a cohort of therapy-related myelodysplastic syndrome, tCMML had lower TP53 mutation frequency (12% vs 44.4%, P < .001) and less unfavorable outcomes. In summary, tCMML does not exhibit the high-risk features and poor outcomes of t-MNs.

Hematopoietic stem cells with granulo-monocytic differentiation state overcome venetoclax sensitivity in patients with myelodysplastic syndromes.

The molecular mechanisms of venetoclax-based therapy failure in patients with acute myeloid leukemia were recently clarified, but the mechanisms by which patients with myelodysplastic syndromes (MDS) acquire secondary resistance to venetoclax after an initial response remain to be elucidated. Here, we show an expansion of MDS hematopoietic stem cells (HSCs) with a granulo-monocytic-biased transcriptional differentiation state in MDS patients who initially responded to venetoclax but eventually relapsed. While MDS HSCs in an undifferentiated cellular state are sensitive to venetoclax treatment, differentiation towards a granulo-monocytic-biased transcriptional state, through the acquisition or expansion of clones with STAG2 or RUNX1 mutations, affects HSCs' survival dependence from BCL2-mediated anti-apoptotic pathways to TNFα-induced pro-survival NF-κB signaling and drives resistance to venetoclax-mediated cytotoxicity. Our findings reveal how hematopoietic stem and progenitor cell (HSPC) can eventually overcome therapy-induced depletion and underscore the importance of using close molecular monitoring to prevent HSPC hierarchical change in MDS patients enrolled in clinical trials of venetoclax.

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.

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.

Targetable genetic abnormalities in patients with acute myeloblastic leukemia across age groups.

Incidence of potential targetable genetic abnormalities by age in AML.

Oral decitabine plus cedazuridine and venetoclax in patients with higher-risk myelodysplastic syndromes or chronic myelomonocytic leukaemia: a single-centre, phase 1/2 study.

BACKGROUND: Hypomethylating agents are approved in higher-riskmyelodysplastic syndromes. The combination of a hypomethylating agent with venetoclax is standard of care in acute myeloid leukaemia. We investigated the safety and activity of the first totally oral combination of decitabine plus cedazuridine and venetoclax in patients with higher-risk-myelodysplastic syndromes and chronic myelomonocytic leukaemia. METHODS: We did a single-centre, dose-escalation and dose-expansion, phase 1/2, clinical trial. Patients with treatment-naive higher-risk-myelodysplastic syndromes or chronic myelomonocytic leukaemia (risk level categorised as intermediate-2 or higher by the International Prognostic Scoring System) with excess blasts (>5%). Treatment consisted of oral decitabine 35 mg plus cedazuridine 100 mg on days 1-5 and venetoclax (variable doses of 100-400 mg, day 1 to 14, 28-day cycle). The primary outcomes were safety for the phase 1 part and the overall response for the phase 2 part of the study. The trial is ongoing and this analysis was not prespecified. This study is registered with ClinicalTrials.gov, NCT04655755, and is currently enrolling participants. FINDINGS: Between Jan 21, 2021, and Jan 20, 2023, we enrolled 39 patients (nine in phase 1 and 30 in phase 2). The median age was 71 years (range 27-94), 28 (72%) patients were male, and 11 (28%) were female. The maximum tolerated dose was not reached, and the recommended phase 2 dose was established as oral decitabine 35 mg plus cedazuridine 100 mg for 5 days and venetoclax (400 mg) for 14 days. The most common grade 3-4 adverse events were thrombocytopenia (33 [85%] of 39), neutropenia (29 [74%]), and febrile neutropenia (eight [21%]). Four non-treatment-related deaths occurred on the study drugs due to sepsis (n=2), lung infection (n=1), and undetermined cause (n=1). The median follow-up time was 10·8 months (IQR 5·6-16·4). The overall response rate was 95% (95% CI 83-99; 37/39). 19 (49%) patients proceeded to hematopoietic stem-cell transplantation. INTERPRETATION: This early analysis suggests that the combination of oral decitabine plus cedazuridine with venetoclax for higher-risk-myelodysplastic syndromes and chronic myelomonocytic leukaemia is safe in most patients, with encouraging activity. Longer follow-up will be needed to confirm these data. FUNDING: MD Anderson Cancer Center, MDS/AML Moon Shot, Genentech/AbbVie, and Astex Pharmaceuticals.

Cytogenetic and Molecular Associations with Outcomes in Higher-Risk Myelodysplastic Syndromes Treated with Hypomethylating Agents plus Venetoclax.

PURPOSE: Hypomethylating agents (HMA) combined with venetoclax are an emerging therapeutic strategy for higher-risk myelodysplastic syndromes (HR-MDS). The cytogenetic and molecular factors associated with outcomes with this combination for HR-MDS are incompletely understood. EXPERIMENTAL DESIGN: We pooled patient data from 3 prospective trials evaluating HMA-venetoclax in HR-MDS to study associations between cytogenetic and molecular factors and overall response rate (ORR), overall survival (OS), and event-free survival (EFS). The Kaplan-Meier method was used to estimate time-to-event endpoints. Univariate and multivariate analyses using logistic regression (for ORR) or the Cox proportional hazards model (for OS and EFS) were used to identify associations between clinical, cytogenetic, and molecular factors and outcomes. RESULTS: A total of 80 patients (52 HMA-naïve, 28 HMA-failure) were included. ORR was 90% in HMA-naïve and 57% in HMA-failure. Median OS was 28.2 and 8.3 months in HMA-naïve and HMA-failure, respectively. Median EFS was 17.9 and 5.5 months in HMA-naïve and HMA-failure, respectively. In addition, 24/52 (46%) of the HMA-naïve and 3/28 (11%) of the HMA-failure patients proceeded to allogeneic stem cell transplantation (SCT). Factors associated with inferior outcomes were prior HMA failure, complex cytogenetics, trisomy 8, TP53 mutations, and RAS pathway mutations. Mutations in RNA splicing, DNA methylation, and ASXL1 appeared favorable. Blast percentage was not predictive of outcomes. CONCLUSIONS: Knowledge of cytogenetic and molecular alterations may help identify which patients with HR-MDS benefit the most from venetoclax.

Prognostic risk signature in patients with acute myeloid leukemia treated with hypomethylating agents and venetoclax.

ABSTRACT: Hypomethylating agents (HMAs) and venetoclax (Ven) represent the standard of care for patients with acute myeloid leukemia (AML) who are ineligible for intensive chemotherapy. However, the European LeukemiaNet (ELN) risk classifications have been validated for patients treated with intensive therapy. In this study, we validate a recently proposed new molecular prognostic risk signature (mPRS) for patients with AML treated with HMAs and Ven. This classification allocated patients to favorable, intermediate (N/KRAS or FLT3-internal tandem duplication mutations), and lower (TP53 mutations) benefit groups. We retrospectively analyzed 159 patients treated with HMA and Ven. The mPRS classification allocated 74 (47%), 31 (19%), and 54 (34%) patients to the higher, intermediate, and lower-benefit groups, respectively. The overall response rate was 71% (86%, 54%, and 59% in the higher, intermediate, and lower-benefit groups, respectively). The median overall survival (OS) and event-free survival (EFS) times were 30 and 19 months, respectively, in the higher-benefit group; 12 and 8 months in the intermediate-benefit group; and 5 and 4 months in the lower-benefit group (P < .001). The C-index for OS and EFS was higher when stratifying patients according to mPRS classification than with the ELN 2022 classification. The 2-year cumulative incidence of relapse was 35%, 70%, and 60% in the higher, intermediate, and lower-benefit groups, respectively (P = .005). The mPRS classification accurately segregated groups of patients with AML treated with HMA plus Ven. In these patients, N/KRAS and TP53 mutations appear to negatively affect outcomes; therefore, new treatment approaches are warranted.

Characteristics and clinical outcomes of patients with myeloid malignancies and DDX41 variants.

DDX41 is the most frequently mutated gene in myeloid neoplasms associated with germline predisposition including myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML). We analyzed 3795 patients with myeloid neoplasms and identified 151 (4%) with DDX41 variants and a diagnosis of AML (n = 96), MDS (n = 52), and chronic myelomonocytic leukemia (n = 3). The most frequent DDX41 variants were the somatic variant p.R525H, followed by the germline variants p.M1I and p.D140fs. Most neoplasms had a normal karyotype (59%) and the most frequent co-mutations were TP53 (16%) and ASXL1 (15%). 30% of patients had no concomitant mutations besides DDX41 mutation. Patients with myeloid malignancies and DDX41 variants responded well to therapy, with an overall response rate for patients with treatment naïve AML and MDS of 87% and 84%, respectively. The median overall survival (mOS) of patients with treatment-naïve AML or MDS was 49 and 71 months, respectively. Patients with AML treated with low-intensity regimens including venetoclax had an improved survival (2-year OS 91% vs. 60%, p = .02) and lower cumulative incidence of relapse compared to those treated without venetoclax (10% vs. 56%, p = .03). In the 33% of patients receiving hematopoietic stem cell transplantation, the 2-year OS was 80% and 85% for AML and MDS, respectively.

Sustained remissions in CLL after frontline FCR treatment with very-long-term follow-up.

Chemoimmunotherapy with fludarabine, cyclophosphamide, and rituximab (FCR) achieves durable remissions, with flattening of the progression-free survival (PFS) curve in patients with mutated immunoglobulin heavy chain variable gene (IGHV-M). We updated long-term follow-up results from the original 300-patient FCR study initiated at MD Anderson in 1999. The current median follow-up is 19.0 years. With this extended follow-up, the median PFS for patients with IGHV-M was 14.6 years vs 4.2 years for patients with unmutated IGHV (IGHV-UM). Disease progression beyond 10 years was uncommon. In total, 16 of 94 (17%) patients in remission at 10 years subsequently progressed with the additional follow-up compared with the patients in our prior report in 2015. Only 4 of 45 patients (9%) with IGHV-M progressed beyond 10 years. Excluding Richter transformation, 96 of 300 patients (32%) developed 106 other malignancies, with 19 of 300 (6.3%) developing therapy-related myeloid neoplasms (tMNs), which were fatal in 16 of 19 (84%). No pretreatment patient characteristics predicted the risk of tMNs. In summary, FCR remains an option for patients with IGHV-M chronic lymphocytic leukemia (CLL), with a significant fraction achieving functional cure of CLL. A risk-benefit assessment is warranted when counseling patients, balancing potential functional cure with the risk of late relapses and serious secondary malignancies.

Evolving trends and outcomes in older patients with acute myeloid leukemia including allogeneic stem cell transplantation.

Outcomes in older patients with acute myeloid leukemia (AML) have historically been poor. Given advances in low-intensity therapy (LIT) and stem cell transplantation (SCT), we performed a retrospective single-center study to evaluate the contemporary outcomes of this population. We reviewed all patients ≥60 years with newly diagnosed AML between 2012 and 2021 and analyzed treatment and SCT-related trends and outcomes. We identified 1073 patients with a median age of 71 years. Adverse clinical and cytomolecular findings were frequent within this cohort. In total, 16% of patients were treated with intensive chemotherapy, 51% with LIT alone, and 32% with LIT plus venetoclax. The composite complete remission rate with LIT plus venetoclax was 72%, which was higher than with LIT alone (48%, p < .0001) and comparable to intensive chemotherapy (74%, p = .6). The median overall survival (OS) with intensive chemotherapy, LIT, and LIT plus venetoclax was 20.1, 8.9, and 12.1 months, respectively. 18% of patients received SCT. SCT rates were 37%, 10%, and 22% in patients treated with intensive chemotherapy, LIT, and LIT plus venetoclax, respectively. The 2-year OS, relapse-free survival (RFS), cumulative incidence (CI) of relapse, and CI of treatment-related mortality with frontline SCT (n = 139) were 59%, 52%, 27%, and 22%, respectively. By landmark analysis, patients undergoing frontline SCT had superior OS (median 39.6 vs. 21.4 months, p < .0001) and RFS (30.9 vs. 12.1 months, p < .0001) compared with responding patients who did not. Outcomes in older patients with AML are improving with more effective LIT. Measures should be pursued to increase access to SCT in older patients.

Undetectable measurable residual disease is associated with improved outcomes in AML irrespective of treatment intensity.

Acute myeloid leukemia (AML) can be treated with either high- or low-intensity regimens. Highly sensitive assays for measurable residual disease (MRD) now allow for a more precise assessment of response quality. We hypothesized that treatment (Rx) intensity may not be a key predictor of outcomes, assuming that an optimal response to therapy is achieved. We performed a single-center retrospective study including 635 patients with newly diagnosed AML responding to either intensive cytarabine/anthracycline-based chemotherapy (IA; n = 385) or low-intensity venetoclax-based regimens (LOW + VEN; n = 250) and who had adequate flow cytometry-based MRD testing performed at the time of best response. The median overall survival (OS) was 50.2, 18.2, 13.6, and 8.1 months for the IA MRD-, LOW + VEN MRD-, IA MRD+, and LOW + VEN MRD+ cohorts, respectively. The 2-year cumulative incidence of relapse (CIR) was 41.1%, 33.5%, 64.2%, and 59.9% for the IA MRD-, LOW + VEN MRD-, IA MRD+, and LOW + VEN MRD+ cohorts, respectively. The CIR was similar between patients within MRD categories irrespective of the treatment regimen received. The IA cohort was enriched for younger patients and favorable AML cytogenetic/molecular categories. Using multivariate analysis, age, best response (complete remission [CR]/CR with incomplete hematologic recovery/morphologic leukemia-free state), MRD status, and European LeukemiaNet (ELN) 2017 risk remained significantly associated with OS, whereas best response, MRD status, and ELN 2017 risk were significantly associated with CIR. Treatment intensity was not significantly associated with either OS or CIR. Achievement of MRD- CR should be the key objective of AML therapy in both high- and low-intensity treatment regimens.

Automated quantification of measurable residual disease in chronic lymphocytic leukemia using an artificial intelligence-assisted workflow.

Detection of measurable residual disease (MRD) in chronic lymphocytic leukemia (CLL) is an important prognostic marker. The most common CLL MRD method in current use is multiparameter flow cytometry, but availability is limited by the need for expert manual analysis. Automated analysis has the potential to expand access to CLL MRD testing. We evaluated the performance of an artificial intelligence (AI)-assisted multiparameter flow cytometry (MFC) workflow for CLL MRD. We randomly selected 113 CLL MRD FCS files and divided them into training and validation sets. The training set (n = 41) was gated by expert manual analysis and used to train the AI model. We then compared the validation set (n = 72) MRD results obtained by the AI-assisted analysis versus those by expert manual analysis using the Pearson correlation coefficient and Bland-Altman plot method. In the validation set, the AI-assisted analysis correctly categorized cases as MRD-negative versus MRD-positive in 96% of cases. When comparing the AI-assisted analysis versus the expert manual analysis, the Pearson r was 0.8650, mean bias was 0.2237 log10 units, and the 95% limit of agreement (LOA) was ±1.0282 log10 units. The AI-assisted analysis performed sub-optimally in atypical immunophenotype CLL and in cases lacking residual normal B cells. When excluding these outlier cases, the mean bias improved to 0.0680 log10 units and the 95% LOA to ±0.2926 log10 units. An automated AI-assisted workflow allows for the quantification of MRD in CLL with typical immunophenotype. Further work is required to improve performance in atypical immunophenotype CLL.

A retrospective study of cladribine and low-dose cytarabine-based regimens for the treatment of chronic myelomonocytic leukemia and secondary acute myeloid leukemia.

BACKGROUND: Patients with higher risk chronic myelomonocytic leukemia (CMML) have limited therapeutic options beyond hydroxyurea and hypomethylating agents (HMAs). Regimens based on a backbone of cladribine (CLAD), low-dose cytarabine (LDAC), and an HMA are effective low-intensity therapies for acute myeloid leukemia (AML). METHODS: The authors conducted a retrospective chart review to evaluate the efficacy of CLAD/LDAC/HMA in CMML and secondary acute myeloid leukemia (sAML) arising from CMML. Responses were evaluated according to the 2006 International Working Group criteria for CMML and the 2017 European LeukemiaNet criteria for AML. The overall survival (OS), leukemia-free survival (LFS), and duration of response were evaluated with the Kaplan-Meier method. Patients were stratified on the basis of prior HMA exposure. RESULTS: The authors identified 21 patients with CMML (eight with HMA-naive CMML and 13 with HMA-failure CMML) and 33 patients with sAML (11 with HMA-naive sAML and 22 with HMA-failure sAML) treated with CLAD/LDAC/HMA-based regimens. The CMML cohort was enriched for high-risk features (proliferative type, elevated blasts, and RAS/MAPK mutations). The overall response rate was 33% in CMML (50% in HMA-naive CMML and 23% in HMA-failure CMML) and 48% in sAML (82% in HMA-naive sAML and 32% in HMA-failure sAML). The median OS was 14.4, 8.8, 42.9, and 2.9 months for HMA-naive CMML, HMA-failure CMML, HMA-naive sAML, and HMA-failure sAML, respectively. The median LFS was 14.4 and 3.9 months for HMA-naive CMML and HMA-failure CMML, respectively. CONCLUSIONS: CLAD/LDAC/HMA-based regimens are effective in a subset of patients with higher risk CMML and sAML arising from CMML who have not previously experienced HMA failure. These findings must be confirmed in prospective studies.

Azacitidine plus venetoclax in patients with high-risk myelodysplastic syndromes or chronic myelomonocytic leukaemia: phase 1 results of a single-centre, dose-escalation, dose-expansion, phase 1-2 study.

BACKGROUND: Therapies beyond hypomethylating agents such as azacitidine are needed in high-risk myelodysplastic syndromes. Venetoclax is an orally bioavailable small molecule BCL-2 inhibitor that is synergistic with hypomethylating agents. We therefore aimed to evaluate the safety, tolerability, and preliminary activity of azacitidine combined with venetoclax for treatment-naive and relapsed or refractory high-risk myelodysplastic syndromes or chronic myelomonocytic leukaemia. METHODS: We did a single centre, dose-escalation, dose-expansion, phase 1-2 trial at the University of Texas MD Anderson Cancer Center (Houston, TX, USA). This Article details the phase 1 results. We enrolled patients (≥18 years) with treatment-naive or relapsed or refractory high-risk myelodysplastic syndromes or chronic myelomonocytic leukaemia and bone marrow blasts of more than 5%. No specific Eastern Cooperative Oncology Group status restriction was used. Patients were treated with intravenous or subcutaneous azacitidine (75 mg/m2) for 5 days and oral venetoclax (100-400 mg) for 7-14 days. The primary outcome was safety and tolerability as well as determination of the maximum tolerated dose and recommended phase 2 dose of the azacitidine and venetoclax combination using a 3 + 3 study design. All patients who received one dose of study drug were included in the analyses. This study is registered with ClinicalTrials.gov, number NCT04160052. The phase 2 dose-expansion part of the trial is ongoing. FINDINGS: Between Nov 12, 2019, and Dec 17, 2021, a total of 23 patients were enrolled in the phase 1 portion of this study (17 [74%] hypomethylating agent naive and six [26%] post-hypomethylating agent failure). 18 (78%) patients were male and five (22%) were female; 21 (91%) were white and two (9%) were Asian. Median follow-up was 13·2 months (IQR 6·8-18·3). The maximum tolerated dose was not reached and the recommended phase 2 dose was established as azacitidine 75 mg/m2 for 5 days plus venetoclax 400 mg for 14 days. The most common grade 3-4 treatment-emergent adverse events were neutropenia (nine [39%] of 23), thrombocytopenia (nine [39%]), lung infection (seven [30%]), and febrile neutropenia (four [17%]). Three deaths due to sepsis, which were not deemed treatment-related, occurred on the study drugs. The overall response rate was 87% (95% CI 66-97; 20 of 23 patients). INTERPRETATION: Azacitidine with venetoclax is safe and shows encouraging activity in patients with high-risk myelodysplastic syndromes or chronic myelomonocytic leukaemia. FUNDING: MD Anderson Cancer Center.

New Approaches to Myelodysplastic Syndrome Treatment.

OPINION STATEMENT: The treatment of myelodysplastic syndromes (MDS) begins with risk stratification using a validated tool such as the International Prognostic Scoring System (IPSS) or its revised version (IPSS-R). This divides patients into lower- and higher- risk categories. Although treatment objectives in lower-risk MDS (LR-MDS) have traditionally been directed at improving cytopenias (usually anemia) as well as quality of life, recent data supports a potential role for early intervention in delaying transfusion dependency. In addition, careful individualized risk stratification incorporating clinical, cytogenetic, and mutational data might help identify patients at higher-than-expected risk for progression. Given the need for supportive care with red blood cell (RBC) transfusions leading to iron overload, iron chelation should be considered for patients with heavy transfusion requirements at risk for end-organ complications. For patients with LR-MDS and isolated anemia, no high-risk features, and endogenous erythropoietin (EPO) levels below 500 U/L, erythropoiesis-stimulating agents (ESAs) can be attempted to improve anemia. Some LR-MDS patient subgroups may also benefit from specific therapies including luspatercept (MDS with ring sideroblasts), lenalidomide (MDS with deletion 5q), or immunosuppressive therapy (hypocellular MDS). LR-MDS patients failing the above options, or those with multiple cytopenias and/or higher-risk features, can be considered for oral low-dose hypomethylating agent (HMA) therapy. Alternatively, these patients may be enrolled on a clinical trial with promising agents targeting the transforming-growth factor beta (TGF-ß) pathway, the hypoxia-inducible factor (HIF) pathway, telomerase activity, inflammatory signaling, or the splicing machinery. In higher-risk MDS (HR-MDS), therapy seeks to modify the natural history of the disease and prolong survival. Eligible patients should be considered for curative allogeneic hematopoietic stem cell transplantation (aHSCT). Despite promising novel combinations, the HMAs azacitidine (AZA) or decitabine (DAC) are still the standard of care for these patients, with intensive chemotherapy-based approaches being a potential option in a small subset of patients. Individuals who fail to respond or progress after HMA experience dismal outcomes and represent a major unmet clinical need. Such patients should be treated as part of a clinical trial if possible. Experimental agents to consider include venetoclax, myeloid cell leukemia 1 (MCL-1) inhibitors, eprenetapopt, CPX-351, immunotherapies (directed towards CD47, TIM3, or CD70), interleukin-1 receptor-associated kinase 4 (IRAK4) inhibitors, pevonedistat, seclidemstat, and eltanexor. In this review, we extensively discuss the current landscape of experimental therapies for both LR- and HR-MDS.