Treatment-Free Remission After Second-Line Nilotinib Treatment in Patients With Chronic Myeloid Leukemia in Chronic Phase: Results From a Single-Group, Phase 2, Open-Label Study.

Background: Treatment-free remission (TFR)-that is, stopping tyrosine kinase inhibitor (TKI) therapy without loss of response-is an emerging treatment goal in chronic myeloid leukemia (CML). Objective: To evaluate TFR after discontinuation of second-line nilotinib therapy. Design: Single-group, phase 2, open-label study. (ClinicalTrials.gov: NCT01698905). Setting: 63 centers in 18 countries. Patients: Adults with CML in chronic phase who received TKI therapy for at least 3 years (>4 weeks with imatinib, then ≥2 years with nilotinib) and achieved MR4.5 (BCR-ABL1 ≤0.0032% on the International Scale [BCR-ABL1IS]) while receiving nilotinib entered a 1-year consolidation phase. Those with sustained MR4.5 during consolidation were eligible to enter TFR. Interventions: Patients received nilotinib during consolidation; those who entered TFR stopped treatment. Patients with loss of major molecular response (MMR) (BCR-ABL1IS ≤0.1%) or confirmed loss of MR4 (BCR-ABL1IS ≤0.01%) during TFR reinitiated nilotinib treatment. Measurements: Proportion of patients without loss of MMR, confirmed loss of MR4, or treatment reinitiation within 48 weeks of stopping treatment (primary end point). Results: 163 patients who had switched from imatinib to nilotinib (for reasons including resistance, intolerance, and physician preference) enrolled in the study and entered the consolidation phase. Of these patients, 126 met the criteria for entering the TFR phase, and 73 (58% [95% CI, 49% to 67%]) and 67 (53% [CI, 44% to 62%]) maintained TFR at 48 weeks (primary end point) and 96 weeks, respectively. Of the 56 patients who reinitiated nilotinib therapy, 55 regained MMR or better and 52 regained MR4.5. None had CML progression to accelerated phase or blast crisis. Musculoskeletal pain was more frequent during the first 48 weeks after nilotinib discontinuation. Limitation: The study included a heterogeneous patient population and was not designed to compare outcomes between patients continuing and those stopping treatment. Conclusion: TFR seems achievable in patients with sustained MR4.5 after switching to nilotinib. Primary Funding Source: Novartis Pharmaceuticals Corporation.

Nilotinib dose-optimization in newly diagnosed chronic myeloid leukaemia in chronic phase: final results from ENESTxtnd.

The Evaluating Nilotinib Efficacy and Safety in Clinical Trials-Extending Molecular Responses (ENESTxtnd) study was conducted to evaluate the kinetics of molecular response to nilotinib in patients with newly diagnosed chronic myeloid leukaemia in chronic phase and the impact of novel dose-optimization strategies on patient outcomes. The ENESTxtnd protocol allowed nilotinib dose escalation (from 300 to 400 mg twice daily) in the case of suboptimal response or treatment failure as well as dose re-escalation for patients with nilotinib dose reductions due to adverse events. Among 421 patients enrolled in ENESTxtnd, 70·8% (95% confidence interval, 66·2-75·1%) achieved major molecular response (BCR-ABL1 ≤ 0·1% on the International Scale) by 12 months (primary endpoint). By 24 months, 81·0% of patients achieved major molecular response, including 63·6% (56 of 88) of those with dose escalations for lack of efficacy and 74·3% (55 of 74) of those with dose reductions due to adverse events (including 43 of 54 patients with successful re-escalation). The safety profile of nilotinib was consistent with prior studies. The most common non-haematological adverse events were headache, rash, and nausea; cardiovascular events were reported in 4·5% of patients (grade 3/4, 3·1%). The study was registered at clinicaltrials.gov (NCT01254188).

Frequent variations in cancer-related genes may play prognostic role in treatment of patients with chronic myeloid leukemia.

BACKGROUND: Genome variability of host genome and cancer cells play critical role in diversity of response to existing therapies and overall success in treating oncological diseases. In chronic myeloid leukemia targeted therapy with tyrosine kinase inhibitors demonstrates high efficacy in most of the patients. However about 15 % of patients demonstrate primary resistance to standard therapy. Whole exome sequencing is a good tool for unbiased search of genetic variations important for prognosis of survival and therapy efficacy in many cancers. We apply this approach to CML patients with optimal response and failure of tyrosine kinase therapy. RESULTS: We analyzed exome variations between optimal responders and failures and found 7 variants in cancer-related genes with different genotypes in two groups of patients. Five of them were found in optimal responders: rs11579366, rs1990236, rs176037, rs10653661, rs3803264 and two in failures: rs3099950, rs9471966. These variants were found in genes associated with cancers (ANKRD35, DNAH9, MAGEC1, TOX3) or participating in cancer-related signaling pathways (THSD1, MORN2, PTCRA). CONCLUSION: We found gene variants which may become early predictors of the therapy outcome and allow development of new early prognostic tests for estimation of therapy efficacy in CML patients. Normal genetic variation may influence therapy efficacy during targeted treatment of cancers.

Long-term efficacy and safety of bosutinib in patients with advanced leukemia following resistance/intolerance to imatinib and other tyrosine kinase inhibitors.

Long-term efficacy and safety of bosutinib (≥4 years follow-up from last enrolled patient) were evaluated in an ongoing phase 1/2 study in the advanced leukemia cohort with prior treatment failure (accelerated-phase [AP, n = 79] chronic myeloid leukemia [CML], blast-phase [BP, n = 64] CML, acute lymphoblastic leukemia [ALL, n = 24]). Fourteen AP, 2 BP, and 1 ALL patient remained on bosutinib at 4 years (vs. 38, 8, 1 at 1 year); median (range) treatment durations: 10.2 (0.1-88.6), 2.8 (0.03-55.9), 0.97 (0.3-89.2) months. Among AP and BP patients, 57% and 28% newly attained or maintained baseline overall hematologic response (OHR); 40% and 37% attained/maintained major cytogenetic response (MCyR) by 4 years (most by 12 months). In responders at 1 versus 4 years, Kaplan-Meier (KM) probabilities of maintaining OHR were 78% versus 49% (AP) and 28% versus 19% (BP); KM probabilities of maintaining MCyR were 65% versus 49% (AP) and 21% versus 21% (BP). Most common AEs (AP, BP) were gastrointestinal (96%; 83%), primarily diarrhea (85%; 64%), which was typically low grade (maximum grade 1/2: 81%; 59%) and transient; no patient discontinued due to diarrhea. Serious AEs occurred in 44 (56%) AP and 37 (58%) BP patients, most commonly pneumonia (n = 9) for AP and pyrexia (n = 6) for BP; 11 and 13 died within 30 days of last dose (2 considered bosutinib-related [AP] per investigator). Responses were durable in ∼50% AP responders at 4 years (∼25% BP patients responded at year 1, suggesting possible bridge-to-transplant role in BP patients); toxicity was manageable.

Bosutinib efficacy and safety in chronic phase chronic myeloid leukemia after imatinib resistance or intolerance: Minimum 24-month follow-up.

Bosutinib is an orally active, dual Src/Abl tyrosine kinase inhibitor for treatment of chronic myeloid leukemia (CML) following resistance/intolerance to prior therapy. Here, we report the data from the 2-year follow-up of a phase 1/2 open-label study evaluating the efficacy and safety of bosutinib as second-line therapy in 288 patients with chronic phase CML resistant (n = 200) or intolerant (n = 88) to imatinib. The cumulative response rates to bosutinib were as follows: 85% achieved/maintained complete hematologic response, 59% achieved/maintained major cytogenetic response (including 48% with complete cytogenetic response), and 35% achieved major molecular response. Responses were durable, with 2-year estimates of retaining response >70%. Two-year probabilities of progression-free survival and overall survival were 81% and 91%, respectively. The most common toxicities were primarily gastrointestinal adverse events (diarrhea [84%], nausea [45%], vomiting [37%]), which were primarily mild to moderate, typically transient, and first occurred early during treatment. Thrombocytopenia was the most common grade 3/4 hematologic laboratory abnormality (24%). Outcomes were generally similar among imatinib-resistant and imatinib-intolerant patients and did not differ with age. The longer-term results of the present analysis confirm that bosutinib is an effective and tolerable second-line therapy for patients with imatinib-resistant or imatinib-intolerant chronic phase CML. ClinicalTrials.gov Identifier: NCT00261846.

Safety and efficacy of bosutinib (SKI-606) in chronic phase Philadelphia chromosome-positive chronic myeloid leukemia patients with resistance or intolerance to imatinib.

Bosutinib, a dual Src/Abl kinase inhibitor, has shown potent activity against chronic myeloid leukemia (CML). In this phase 1/2 study we evaluated bosutinib in patients with chronic phase imatinib-resistant or imatinib-intolerant CML. Part 1 was a dose-escalation study to determine the recommended starting dose for part 2; part 2 evaluated the efficacy and safety of bosutinib 500 mg once-daily dosing. The study enrolled 288 patients with imatinib-resistant (n = 200) or imatinib-intolerant (n = 88) CML and no other previous kinase inhibitor exposure. At 24 weeks, 31% of patients achieved major cytogenetic response (primary end point). After a median follow-up of 24.2 months, 86% of patients achieved complete hematologic remission, 53% had a major cytogenetic response (41% had a complete cytogenetic response), and 64% of those achieving complete cytogenetic response had a major molecular response. At 2 years, progression-free survival was 79%; overall survival at 2 years was 92%. Responses were seen across Bcr-Abl mutants, except T315I. Bosutinib exhibited an acceptable safety profile; the most common treatment-emergent adverse event was mild/moderate, typically self-limiting diarrhea. Grade 3/4 nonhematologic adverse events (> 2% of patients) included diarrhea (9%), rash (9%), and vomiting (3%). These data suggest bosutinib is effective and tolerable in patients with chronic phase imatinib-resistant or imatinib-intolerant CML. This trial was registered at http://www.clinicaltrials.gov as NCT00261846.

Clinical Outcomes in Patients With COVID-19 and Hematologic Disease.

BACKGROUND: Patients with hematologic diseases are at higher risk of the SARS-CoV-2 infection and more severe clinical outcomes of the coronavirus disease. CHRONOS19 is an observational prospective cohort study with the aim to determine the short and longer-term clinical outcomes, risk factors for disease severity and mortality, and rates of postinfectious immunity in patients with malignant and nonmalignant hematologic diseases and COVID-19. PATIENTS AND METHODS: Overall, 666 patients were enrolled in the study, of which 626 were included in the final data analysis. The primary endpoint was 30-days all-cause mortality. Secondary endpoints included COVID-19 complications, rates of ICU admission and mechanical ventilation, outcomes of a hematologic disease in SARS-CoV-2 infected patients, overall survival, and risk factors for disease severity and mortality. Data from 15 centers were collected at 30, 90, and 180 days after COVID-19 was diagnosed and were managed using a web-based e-data capture platform. All evaluations were performed in the pre-omicron period of COVID-19 pandemic. RESULTS: Thirty-days all-cause mortality was 18.9%. The predominant cause of death (in 80% of cases) were COVID-19 complications. At 180 days, the majority (70%) of additional deaths were due to hematologic disease progression. At a median follow-up of 5.7 [0.03-19.04] months, 6-months overall survival was 72% [95% CI: 0.69-0.76]. One-third of patients had severe SARS-CoV-2 disease. The rate of ICU admission was 22% with 77% of these patients requiring mechanical ventilation, with poor survival rate. A univariate analysis revealed that older age (≥ 60 years), male sex, malignant hematologic disease, myelotoxic agranulocytosis, transfusion dependence, refractory disease or relapse, diabetes among comorbidities, any complications, especially ARDS alone or in combination with CRS, admission to an ICU, and mechanical ventilation were associated with higher risks of mortality. Treatment of the hematologic disease was changed, postponed, or canceled in 63% of patients. At a longer follow-up (90 and 180 days), the status of the hematologic disease changed in 7.5% of patients. CONCLUSION: Patients with hematologic disease and COVID-19 have high mortality rates, predominantly due to COVID-19 complications. At a longer-term follow-up, no significant impact of COVID-19 on the course of a hematologic disease was revealed.

Long-term treatment-free remission in patients with chronic myeloid leukemia after second-line nilotinib: ENESTop 5-year update.

The ENESTop study evaluated treatment-free remission (TFR) in patients with chronic myeloid leukemia (CML) in chronic phase who had received ≥3 years of tyrosine kinase inhibitor therapy and achieved sustained deep molecular response only after switching from imatinib to nilotinib. After 1-year nilotinib consolidation, 126 patients attempted TFR. At 48 weeks (primary analysis), 57.9% (73/126) were in TFR. In the present analysis at 5 years, 42.9% (54/126) were in TFR. Since the 48-week analysis, among patients who left the TFR phase, 58% (11/19) did not have a loss of molecular response and discontinued for other reasons. Of the 59 patients who reinitiated nilotinib upon loss of major molecular response (MMR) or confirmed loss of MR4, 98.3% regained MMR, 94.9% regained MR4, and 93.2% regained MR4.5. Overall adverse event rates decreased over the 5 years of TFR. In patients reinitiating nilotinib, there was a cumulative increase in cardiovascular events with longer nilotinib exposure. No disease progression or CML-related deaths were reported. Overall, these results confirm the durability and safety of TFR for patients receiving second-line nilotinib. Cardiovascular risk should be carefully managed, particularly when reinitiating treatment after TFR.

Analysis of the Mortality of Russian Patients With Chronic Myeloid Leukemia in the Multicenter EUTOS ELN Population-based Study (EUTOS-PBS).

INTRODUCTION: Russia took part in the multicenter population-based study (Europe) and included 6.8% adult patients with newly diagnosed chronic myeloid leukemia (CML). The objective of this study was to analyze the mortality in the Russian cohort of patients with newly diagnosed CML in the EUTOS PBS observational study. PATIENTS AND METHODS: The analyzed cohort consisted of 197 patients (>18 years) with Ph+/BCR-ABL1+ CML diagnosed in the period from October 1, 2009 through December 31, 2012 from 6 regions of Russia. The distribution of the phases of CML were: chronic phase (CP), 93.4% and accelerated phase (AP) + blast crisis (BC), 6% + 0.6%. The median age was 50 years (range, 18-82 years); the male/female ratio was equal. RESULTS: The overall survival (OS) at 5, 6, and 7 years was 80% (95% confidence interval [CI], 72%-86%), 78% (95% CI, 65%-80%), and 73% (95% CI, 65%-80%), respectively (P < .001). The 5-year OS in patients with AP and BC was 39%. In Russia, the study was prolonged, with a median follow-up of 77 months (range, 0.7-108 months): 141 (71.5%) patients were alive, 47 (24%) patients died, and the status of 9 (4.5%) patients is was unknown. Forty-seven (23.8%) patients died during the follow-up period. The largest number of deaths was observed in the first year after the CML diagnosis: 17 (36%) of 47 cases, 3 of 17 died refusing the CML treatment. At the seventh year of CML therapy, 1 patient died after allogenic hematopoietic stem cell transplantation. The causes of death were: (1) progression of CML to AP/BC in 20 (43%) patients; (2) death in remission in 5 (11%) patients with complete cytogenetic response (CCyR) and/or major molecular response; and (3) death without progression to AP/BC but with signs of leukemia in 22 (46%) patients. The 5-year cumulative incidence of death from all reasons was 20%; the cumulative incidence of CML-related and non-CML-related death at the fifth year was 18% and 11%, respectively. CONCLUSION: In general, the results of treatment in the Russian population sample of non-selected patients with CML were comparable with the data of the total European cohort. The CML-related deaths prevailed in the first year of CML therapy. The appropriate monitoring and therapy interventions during the first year of CML treatment are apparently important for the long-term treatment results.

Exome, transcriptome and miRNA analysis don't reveal any molecular markers of TKI efficacy in primary CML patients.

BACKGROUND: Approximately 5-20% of chronic myeloid leukemia (CML) patients demonstrate primary resistance or intolerance to imatinib. None of the existing predictive scores gives a good prognosis of TKI efficacy. Gene polymorphisms, expression and microRNAs are known to be involved in the pathogenesis of TKI resistance in CML. The aim of our study is to find new molecular markers of TKI therapy efficacy in CML patients. METHODS: Newly diagnosed patients with Ph+ CML in chronic phase were included in this study. Optimal and non-optimal responses to TKI were estimated according to ELN 2013 recommendation. We performed genotyping of selected polymorphisms in 62 blood samples of CML patients, expression profiling of 33 RNA samples extracted from blood and miRNA profiling of 800 miRNA in 12 blood samples of CML patients. RESULTS: The frequencies of genotypes at the studied loci did not differ between groups of patients with an optimal and non-optimal response to TKI therapy. Analysis of the expression of 34,681 genes revealed 26 differently expressed genes (p < 0.05) in groups of patients with different TKI responses, but differences were very small and were not confirmed by qPCR. Finally, we did not find difference in miRNA expression between the groups. CONCLUSIONS: Using modern high-throughput methods such as whole-exome sequencing, transcriptome and miRNA analysis, we could not find reliable molecular markers for early prediction of TKI efficiency in Ph+ CML patients.

Copy number variation analysis in cytochromes and glutathione S-transferases may predict efficacy of tyrosine kinase inhibitors in chronic myeloid leukemia.

Chronic myeloid leukemia (CML) is a myeloproliferative disease characterized by the presence of BCR/ABL fusion gene in leukemic cells, which promotes uncontrolled cell proliferation. Up to 20% of CML patients show primary resistance or non-optimal response to tyrosine kinase inhibitor (TKI) therapy. We investigated the association between copy number variation (CNV) in glutathione S-transferases (GST) and cytochromes (CYP) and the response rate to TKI. We enrolled 47 patients with CML: 31 with an optimal response and 16 with failure at 6 months in accordance with European LeukemiaNet 2013 recommendations. CNV detection was performed using SALSA MLPA P128-C1 Cytochrome P450 probe mix. Patients with optimal response and with failure of TKI therapy showed different frequencies of wild type and mutated CYPs and GST (p<0.0013). Validation in the group of 15 patients proved high prognostic value (p = 0.02): positive and negative predictive value 83% and 78%; sensitivity and specificity 71% and 88%. Wild type genotypes of CYP and GST associate with a worse response to TKI treatment in CML patients. This test can be recommended for further clinical trials.

Phase I to II multicenter study of oblimersen sodium, a Bcl-2 antisense oligonucleotide, in patients with advanced chronic lymphocytic leukemia.

PURPOSE: To determine the maximum-tolerated dose (MTD), efficacy, safety, and pharmacokinetics of oblimersen sodium in patients with advanced chronic lymphocytic leukemia (CLL). PATIENTS AND METHODS: Eligible patients had relapsed or refractory CLL after treatment with fludarabine. Oblimersen was administered at doses ranging from 3 to 7 mg/kg/d as a 5-day continuous intravenous infusion in cycle 1 and as a 7-day continuous intravenous infusion in subsequent cycles every 3 weeks in stable or responding patients. RESULTS: Forty patients were enrolled and treated (14 patients in phase I and 26 patients in phase II). Dose-limiting reactions in phase I included hypotension and fever, and the MTD for phase II dosing was established at 3 mg/kg/d. Two (8%) of 26 assessable patients achieved a partial response. Other evidence of antitumor activity included > or = 50% reduction in splenomegaly (seven of 17 patients; 41%), complete disappearance of hepatomegaly (two of seven patients; 29%), > or = 50% reduction of lymphadenopathy (seven of 22 patients; 32%), and > or = 50% reduction in circulating lymphocyte counts (11 of 22 patients; 50%). Adverse events included transient hypotension, fever, fatigue, night sweats, diarrhea, nausea, vomiting, hypokalemia, and cough. Plasma concentrations of oblimersen (parent drug) and its major metabolites were variable. Renal clearance represented only a small portion of total parent drug clearance. CONCLUSION: Dosing with oblimersen sodium in patients with CLL is limited by development of a cytokine release syndrome that is characterized by fever, hypotension, and back pain. Oblimersen sodium has modest single-agent activity in heavily pretreated patients with advanced CLL, and further evaluation of its activity in combination with cytotoxic drugs is warranted.