CALR mutation burden in essential thrombocythemia and disease outcome.

ABSTRACT: Among 281 patients with essential thrombocythemia and calreticulin (CALR) mutation, we found a variant allele frequency of ≥60% to be associated with significantly shortened myelofibrosis-free survival, mostly apparent with CALR type-1 and CALR type-indeterminate mutations.

Cardiac events in newly diagnosed acute myeloid leukaemia during treatment with venetoclax + hypomethylating agents.

Among 301 newly diagnosed patients with acute myeloid leukaemia receiving venetoclax and a hypomethylating agent, 23 (7.6%) experienced major cardiac complications: 15 cardiomyopathy, 5 non-ST elevation myocardial infarction and/or 7 pericarditis/effusions. Four patients had more than one cardiac complication. Baseline characteristics included median age ± interquartile range; 73 ± 5 years; 87% males; 96% with cardiovascular risk factors; and 90% with preserved baseline ejection fraction. In multivariate analysis, males were more likely (p = 0.02) and DNMT3A-mutated cases less likely (p < 0.01) to be affected. Treatment-emergent cardiac events were associated with a trend towards lower composite remission rates (43% vs. 62%; p = 0.09) and shorter survival (median 7.7 vs. 13.2 months; p < 0.01). These observations were retrospectively retrieved and warrant further prospective examination.

Venetoclax and hypomethylating agent combination therapy in newly diagnosed acute myeloid leukemia: Genotype signatures for response and survival among 301 consecutive patients.

Venetoclax + hypomethylating agent (Ven-HMA) is currently the standard frontline therapy for older/unfit patients with newly diagnosed acute myeloid leukemia (ND-AML). Our objective in the current retrospective study of 301 adult patients (median age 73 years; 62% de novo) with ND-AML was to identify molecular predictors of treatment response to Ven-HMA and survival; European LeukemiaNet (ELN) genetic risk assignment was favorable 15%, intermediate 16%, and adverse 69%. Complete remission, with (CR) or without (CRi), count recovery, was documented in 182 (60%) patients. In multivariable analysis, inclusive of mutations only, "favorable" predictors of CR/CRi were NPM1 (86% vs. 56%), IDH2 (80% vs. 58%), and DDX41 (100% vs. 58%) and "unfavorable" TP53 (40% vs. 67%), FLT3-ITD (36% vs. 63%), and RUNX1 (44% vs. 64%) mutations; significance was sustained for each mutation after adjustment for age, karyotype, and therapy-related qualification. CR/CRi rates ranged from 36%, in the presence of unfavorable and absence of favorable mutation, to 91%, in the presence of favorable and absence of unfavorable mutation. At median follow-up of 8.5 months, 174 deaths and 41 allogeneic stem cell transplants (ASCT) were recorded. In multivariable analysis, risk factors for inferior survival included failure to achieve CR/CRi (HR 3.4, 95% CI 2.5-4.8), adverse karyotype (1.6, 1.1-2.6), TP53 mutation (1.6, 1.0-2.4), and absence of IDH2 mutation (2.2, 1.0-4.7); these risk factors were subsequently applied to construct an HR-weighted risk model that performed better than the ELN genetic risk model (AIC 1661 vs. 1750): low (n = 130; median survival 28.9 months), intermediate (n = 105; median 9.6 months), and high (n = 66; median 3.1 months; p < .001); survival in each risk category was significantly upgraded by ASCT. The current study identifies genotype signatures for predicting response and proposes a 3-tiered, CR/CRi-based, and genetics-enhanced survival model for AML patients receiving upfront therapy with Ven-HMA.

Venetoclax duration (14 vs. 21 vs. 28 days) in combination with hypomethylating agent in newly diagnosed acute myeloid leukemia: Comparative analysis of response, toxicity, and survival.

Overall survival and response rates of 270 patients with newly diagnosed acute myeloid leukemia receiving venetoclax (Ven) plus hypomethylating agent, stratified by Ven dosing schedule (Cycle 1 Ven 14 vs. 21 vs. 28 days).

One thousand patients with essential thrombocythemia: the Mayo Clinic experience.

We describe 1000 patients with essential thrombocythemia seen at the Mayo Clinic between 1967 and 2023: median age 58 years (18-90), females 63%, JAK2/CALR/MPL-mutated 62%/27%/3%, triple-negative (TN) 8%, extreme thrombocytosis (ExT; platelets ≥1000 × 109/L) 26%, leukocytosis (leukocyte count >11 × 109/L) 20%, and abnormal karyotype 6%. JAK2-mutated patients were older (median 71 years), and CALR mutated (52 years), and TN (50 years) younger (p < 0.01). Female gender clustered with TN (73%) and JAK2 (69%) vs. CALR/MPL (49%/47%) mutations (p < 0.01). ExT clustered with CALR (type-2 more than type-1) and TN and leukocytosis with JAK2 mutation (p < 0.01). In multivariable analysis, risk factors for overall survival were older age (p < 0.01), male gender (HR 1.8), absolute neutrophil count (ANC) ≥ 8 × 109/L (HR 1.6), absolute lymphocyte count (ALC) < 1.7 × 109/L (HR 1.5), hypertension (HR 1.7), and arterial thrombosis history (HR 1.7); for leukemia-free survival, ExT (HR 2.3) and abnormal karyotype (HR 3.1); for myelofibrosis-free survival, ANC ≥ 8 × 109/L (HR 2.3) and MPL mutation (HR 3.9); for arterial thrombosis-free survival, age ≥60 years (HR 1.9), male gender (HR 1.6), arterial thrombosis history (HR 1.7), hypertension (HR 1.7), and JAK2 mutation (HR 1.8); for venous thrombosis-free survival, male gender (HR 1.8) and venous thrombosis history (HR 3.0). Associations between ExT and leukemic transformation and between ANC and fibrotic progression were limited to JAK2-mutated cases. Aspirin therapy appeared to mitigate both arterial (HR 0.4) and venous (HR 0.4) thrombosis risk. HR-based risk models delineated patients with median survivals ranging from 10 years to not reached and 20-year leukemia/myelofibrosis incidences from 3%/21% to 12.8%/49%. The current study provides both novel and confirmatory observations of essential thrombocythemia.

Decitabine, venetoclax, and ponatinib for advanced phase chronic myeloid leukaemia and Philadelphia chromosome-positive acute myeloid leukaemia: a single-arm, single-centre phase 2 trial.

BACKGROUND: Advanced phase Philadelphia chromosome-positive myeloid disease-consisting of chronic myeloid leukaemia in the myeloid blast phase and in the accelerated phase, and Philadelphia chromosome-positive acute myeloid leukaemia-is associated with poor outcomes. Although previous studies have suggested the benefit of chemotherapy and BCR::ABL1 tyrosine kinase inhibitor combinations, the optimal regimen is uncertain and prospective studies for this rare group of diseases are scant. Preclinical and retrospective clinical data suggest possible synergy between the BCL-2 inhibitor venetoclax and BCR::ABL1 tyrosine kinase inhibitors. We therefore aimed to design a study to evaluate the safety and activity of a novel combination of decitabine, venetoclax, and the third-generation BCR::ABL1 tyrosine kinase inhibitor ponatinib in advanced phase Philadelphia chromosome-positive myeloid diseases. METHODS: For this phase 2 study, patients aged 18 years or older with previously untreated or relapsed or refractory myeloid chronic myeloid leukaemia-blast phase, chronic myeloid leukaemia-accelerated phase, or advanced phase Philadelphia chromosome-positive acute myeloid leukaemia, and an Eastern Cooperative Oncology Group performance status of 0-3 were eligible. Patients were eligible regardless of the number of previous lines of therapy received or previous receipt of ponatinib. Cycle 1 (induction) consisted of a 7-day lead-in of ponatinib 45 mg orally daily (days 1-7), followed by combination therapy with decitabine 20 mg/m2 intravenously on days 8-12, venetoclax orally daily with ramp-up to a maximum dose of 400 mg on days 8-28, and ponatinib 45 mg orally daily on days 8-28. Cycles 2-24 consisted of decitabine 20 mg/m2 intravenously on days 1-5, venetoclax orally 400 mg on days 1-21, and ponatinib orally daily on days 1-28. Response-based dosing of ponatinib was implemented in consolidation cycles, with reduction to 30 mg daily in patients who reached complete remission or complete remission with an incomplete haematological recovery and a reduction to 15 mg daily in patients with undetectable BCR::ABL1 transcripts. The primary endpoint was the composite rate of complete remission or complete remission with incomplete haematological recovery in the intention-to-treat population. Safety was assessed in the intention-to-treat population. This trial was registered with ClinicalTrials.gov (NCT04188405) and is still ongoing. RESULTS: Between July 12, 2020, and July 8, 2023, 20 patients were treated (14 with chronic myeloid leukaemia-blast phase, four with chronic myeloid leukaemia-accelerated phase, and two with advanced phase Philadelphia chromosome-positive acute myeloid leukaemia). The median age was 43 years (IQR 32-58); 13 (65%) patients were male and seven (35%) were female; and 12 (60%) were White, three (15%) were Hispanic, four (20%) were Black, and one (5%) was Asian. 12 (60%) patients had received 2 or more previous BCR::ABL1 tyrosine kinase inhibitors, and 14 (70%) patients had at least one high-risk additional chromosomal abnormality or complex karyotype. The median duration of follow-up was 21·2 months (IQR 14·1-24·2). The complete remission or complete remission with an incomplete haematological recovery rate was 50% (10 of 20 patients); complete remission in one [5%] patient and complete remission with incomplete haematological recovery in nine [45%]). An additional six (30%) patients had a morphologic leukaemia-free state. The most common grade 3-4 non-haematological adverse events were febrile neutropenia in eight (40%) patients, infection in six (30%), and alanine or aspartate transaminase elevation in five (25%). Eight (40%) patients had at least one cardiovascular event of any grade. There were three on-study deaths, none of which was considered related to the study treatment and all from infections in the setting of refractory leukaemia. INTERPRETATION: The combination of decitabine, venetoclax, and ponatinib is safe and shows promising activity in patients with advanced phase chronic myeloid leukaemia, including those with multiple previous therapies or high-risk disease features. Further studies evaluating chemotherapy and venetoclax-based combination strategies using newer-generation BCR::ABL1 tyrosine kinase inhibitors are warranted. FUNDING: Takeda Oncology, the National Institutes of Health, and the National Cancer Institute Cancer Center.

Real-world experience with ponatinib therapy in chronic phase chronic myeloid leukemia: impact of depth of response on survival and prior exposure to nilotinib on arterial occlusive events.

We surveyed the performance of ponatinib, as salvage therapy, in a real-world setting of chronic phase chronic myeloid leukemia (CML-CP). Among 55 consecutive patients (median age 49 years) with relapsed/refractory CML-CP, 35 (64%) had failed ≥3 tyrosine kinase inhibitors (TKIs), 35 (64%) were pre-treated with nilotinib, and 14 (28%) harbored ABL1T315I. At start of ponatinib (median dose 30 mg/day), 40 patients were already in complete hematologic (CHR), 4 in complete cytogenetic (CCyR), 3 in major molecular (MMR) remission, while 8 had not achieved CHR (NR). Ponatinib improved the depth of response in 13 (33%), 3 (75%), 2 (66%), and 4 (50%) patients with CHR, CCyR, MMR, and NR, respectively (p = 0.02). At a median follow-up of 42 months, 13 (23%) deaths, 5 (9%) blast transformations, and 25 (45%) allogeneic transplants were recorded. Five/10-year post-ponatinib survival was 77%/58% with no significant difference when patients were stratified by allogeneic transplant (p = 0.94), ponatinib-induced deeper response (p = 0.28), or a post-ponatinib ≥CCyR vs CHR remission state (p = 0.25). ABL1T315I was detrimental to survival (p = 0.04) but did not appear to affect response. Prior exposure to nilotinib was associated with higher risk of arterial occlusive events (AOEs; 11% vs 0%; age-adjusted p = 0.04). Ponatinib starting/maintenance dose (45 vs 15 mg/day) did not influence either treatment response or AOEs. Our observations support the use of a lower starting/maintenance dose for ponatinib in relapsed/refractory CML-CP but a survival advantage for deeper responses was not apparent and treatment might not overcome the detrimental impact of ABL1T315I on survival. The association between prior exposure to nilotinib and a higher risk of post-ponatinib AOEs requires further validation.