Targeted Therapy of Myelofibrosis

Background. Myelofibrosis (primary myelofibrosis, post-essential trombocythemia myelofibrosis, post-polycythemia myelofibrosis) is the most complex and pressing problem among all Ph-negative myeloproliferative diseases. The present article summarizes the author’s experience of using new Janus kinase inhibitors in routine clinical practice, and compares the data with the results of other clinical research. Aim. To evaluate the use of ruxolitinib in patients with myelofibrosis. Materials & Methods. Our analysis includes 48 patients (21 men and 27 women) with histologically verified myelofibrosis (primary myelofibrosis in 36 cases, post-essential trombocythemia myelofibrosis in 10 cases, and post-polycythemia myelofibrosis in 2 cases) in a chronic stage. All patients received ruxolitinib. Median age at the start of therapy was 60 years (range from 35 to 79). Massive splenomegaly (≥ 10 cm below the costal margin) was found in 34 (71 %) of 48 patients. The initial dose of ruxolitinib was determined by the platelet level. The efficacy of the therapy was evaluated in accordance with ELN 2013 criteria. Results. Median duration of treatment was 18 months (range from 1 to 50 months). Symptoms of intoxication were relieved in 33 of 37 patients (89 %). The spleen size decreased in 64 % of patients. In 33 % of cases spleen size did not change, whereas an increase was observed in 3 % of patients. In the majority of patients hemoglobin level remained stable through the course of treatment. Three of 14 transfusion dependent patients did not require blood transfusions after 3 months of therapy. In patients with high thrombocyte levels prior to ruxolitinib therapy the mean level was approaching normal by the end of the 1st month of treatment. The median JAK2V617F mutant allele burden at the beginning treatment was 56.5 % (n = 20; 22.5–126.1 %). After 6 moths of treatment it accounted for 62.3 % (n = 11; 25.4–79.7 %) and in 12 months accounted for 47.4 % (n = 12; 14.2–102.2 %). By the time of the analysis 42 of 48 patients continued the ruxolitinib treatment (88 %). Death occurred in 4 patients. Overall 1-year (92 %) and 2-year (87 %) survival corresponds to the data of COMFORT-I, COMFORT-II and JUMP clinical trials. Conclusion. Ruxolitinib showed to be an effective treatment for myelofibrosis. The most pronounced and rapid effect ruxolitinib had on the spleen size and the symptoms of intoxication. The tolerability of ruxolitinib was satisfactory in the majority of patients. According to the author’s data, ruxolitinib had a small impact on the JAK2V617F mutant allele burden. The overall survival rate in patients with myelofibrosis, receiving ruxolitinib in the clinical setting was similar to that of in the clinical trials

Clinical Recommendations for the Diagnosis and Treatment of Chronic Myeloid Leukemia

This article is the 4th edition of the recommendations for the diagnosis and treatment of chronic myeloid leukemia. The group of authors reviewed and discussed relevant new publications, and included the significant remarks and comments of experts. Particular attention was paid to the control of risk factors for the development of arterial vascular events and their prevention, and adverse effects of the long-term therapy with tyrosine kinase inhibitors, which were being increasingly reported in recent years

Clinical Experience and Perspectives of Bosutinib Use in Patients with Chronic Myeloid Leukemia

Aim. To evaluate the clinical experience of bosutinib use for treatment of chronic myeloid leukemia (CML) patients with intolerance and resistance to other tyrosine kinase inhibitors (TKI), as well as to compare the obtained results with the data of clinical trials. Materials & Methods. The analysis was conducted on case history records of 51 CML patients (25 men and 26 women; median age was 56 years, range 28–86). By the beginning of bosutinib therapy 37 chronic phase, 8 acceleration phase, and 6 blast crisis patients were included in the study. Bosutinib was administered as second–line TKI treatment in 10 patients, as third–line treatment in 18 patients, and as fourth–line treatment in 23 patients. The causes for switching to bosutinib were poor tolerance of previous TKI therapy in 21 patients and resistance to previous TKI therapy in 30 patients. Results. The median duration of bosutinib treatment was 6 months (range 1–50). Bosutinib toxicity profile and its tolerance in common clinical practice corresponded to the data of clinical trials. Because of adverse events the therapy was discontinued only in 5 (10 %) patients. Complete hematological response was 88 % (persistent response was maintained in 76 % of patients); complete cytogenetic response (CCyR) was 39 %, (persistent response in 37 % of cases); major molecular response (MMR) was 31 % (it was confirmed in 25 % of patients during the last follow-up visit). The efficacy of bosutinib in the real clinical setting was slightly higher compared to the results of clinical trials. This difference was associated with a disease phase, a reason for withdrawal of the previous TKI, line of treatment, BCR–ABL mutations, and the form of them. The therapy was continued in 22 (43 %) patients, most of them reached stable optimal response, both CCyR and MMR. Conclusion. Bosutinib appears to be an acceptable alternative to other TKIs having its specific mechanisms of action and adverse events. The efficacy and safety of bosutinib proved in routine clinical practice are sufficient to recommend it for use in national hematology

Current Genetic Models for Prediction of Primary Myelofibrosis

Aim. To study the relationship of karyotype, JAK2, CALR, and MPL driver mutations and ASXL1 mutation status with the progression and prediction of primary myelofibrosis (PMF). Materials & Methods. The trial included 110 PMF patients (38 men and 72 women), median age was 59 years (range 18–82) with median follow-up after diagnosis of 2.6 years (range 0.1–23). The patients were examined for JAK2, CALR, MPL, and ASXL1 mutations. Restriction fragment length polymorphism technique was used for the analysis of V617F substitution in JAK2 and 515 codon mutation in MPL. CALR (exon 9) and ASXL1 (exon 12) mutation tests were performed using Sanger direct sequencing. In 48 (44 %) out of 110 patients bone marrow cell karyotype was determined. Clinical and hematological parameters and median overall survival (OS) of patients were analyzed with regard to detected genetic aberrations and combinations of them. Results. JAK2, CALR, MPL mutations were detected in 55 (50 %), 28 (25.5 %), and 7 (6.4 %) out of 110 patients, respectively. Triple negative (TN) status was identified in 20 (18.2 %) out of 110 examined patients. ASXL1 mutations were detected in 22 (20 %) out of 110 patients. Out of 48 patients in 32 (66.7 %) normal karyotype, in 3 (6.3 %) favorable karyotype, in 4 (8.3 %) intermediate-prognosis karyotype, and in 9 (18.7 %) unfavorable karyotype were detected. The comparison of clinical and hematological parameters showed a number of significant differences. JAK2-positive patients had a higher hemoglobin level (median 129 g/L; p = 0.021). TN was associated with a high IPSS risk (p = 0.011), low hemoglobin level (median 101 g/L; p = 0.006), continuing drop in platelet count (median 266 × 109/L; p = 0.041), increased lymphocyte count (median 26.9 × 109/L; p = 0.001). The detection of terminating mutations in ASXL1 correlated with palpable enlarged spleen (p = 0.050), reduced platelet count (median 184 × 109/L; p = 0.016), leukocyte count > 25 × 109/L (p = 0.046), and blast count ≥ 1 % (p < 0.001). Univariate regression analysis showed that terminating mutations in ASXL1 (hazard ratio [HR] 2.9; p = 0.018), unfavorable karyotype (HR 8.2; p < 0.001), and TN (ОР 8.1; p < 0.001) had prognostic value for OS. ASXL1 mutation was associated with significantly worse OS in TN patients. Median OS of ASXL1-negative patients without high-risk chromosomal aberrations was significantly longer than in patients with high-risk karyotype and/or ASXL1 mutation. Conclusion. Several genetic defects in tumor cells are associated with phenotypic manifestations of PMF. Based on the results of cytogenetic analysis and mutation determination of JAK2, CALR, MPL, and ASXL1, patients can be classified in different “genetic” risk groups when PMF is diagnosed

Molecular Genetic Markers and Clinical Characteristics of Essential Thrombocythemia

Background & Aims. The presence of different molecular genetic markers of clonality (mutations in JAK2, MPL, CALR) or their absence (triple negative status, TN) in essential thrombocythemia (ET) indicates a biological heterogeneity of the disease and can determine its clinical forms. The aim was to evaluate the association of molecular genetic markers with the clinical form and the prognosis of ET. Materials & Methods. We analyzed the data of 240 patients with ET at the age of 20–91 years (median age 58.7 years), who were observed in the Russian Research Institute of Hematology and Transfusiology from 1999 to 2016 (median observation period 37.2 months). Results. The JAK2V617F (JAK2+) mutation was found in 182 (75.9 %) of 240 patients. CALR (CALR+) mutations were found in 30 (12.5 %): type 1 (CALR1+) mutations in 13/30 (43.3 %) and type 2 (CALR2+) in 17/30 (56.7 %). MPL (MPL+) mutations were found in only 2 (0.8 %) of 240 patients. None of the mutations were detected in 26 (10.8 %) of 240 patients (TN status). Significantly higher platelet counts were observed in CALR1+ and CALR2+ subgroups during the primary diagnosis of ET compared with JAK2+ and TN groups. The mean platelet counts were 1252 × 109/L for CALR2+ and 1079 × 109/L for CALR1+ vs 841 × 109/L (p < 0.001; p = 0.06) and 775 × 109/L (p < 0.001; p = 0.04) for JAK2+ and TN, respectively. Thrombosis was diagnosed in 50 (27.4 %) of 182 patients of the JAK2+ subgroup, in 8 (30.7 %) of the 26 patients of the TN subgroup, and in 2 (18.2 %) of 11 patients of the CALR1+ subgroup. No thrombosis was found in the CALR2+ and MPL+ subgroups (p < 0.001). In general, the CALR1+ status was characterized as the most favorable in terms of prognosis (5-year overall survival rate of 100 %), compared to the least favorable TN status (5-year overall survival rate of 85 %). Conclusion. Mutations in the CALR gene were characterized by a more favorable prognosis in comparison with JAK2+ and TN, as well as a decrease in the risk and frequency of thrombosis, despite higher platelet counts. TN-status of ET was associated with unfavorable prognosis

Genetic Markers of Hereditary Thrombophilia and Risk of Thrombotic Complications in Patients with Polycythemia Vera

Background. Thrombotic complications are one of the main problems of polycythemia vera (PV) treatment. They significantly impair the quality of life of these patients and may lead to the lethal outcome. A thrombotic event often precedes the diagnosis of this hematological disease. The pathogenesis of thrombosis in myeloproliferative neoplasms, PV, in particular, is a complex one. Prescription of antiaggregants in the absence of thrombosis and anticoagulants after a thrombotic event requires special attention and development of corresponding recommendations. The prescription of anticoagulants is impossible without taking into account the risks of hemorrhagic complications, which are also typical for myeloproliferative neoplasms. Aim. Assessment of the impact of hereditary thrombophilia genetic markers on the risk of thrombotic complications in patients with PV. Methods. The study examined 116 patients with PV, who were screened for markers of hereditary thrombophilia: factor V (G1691A, FV Leiden), prothrombin, methylenetetrahydrofolate reductase (MTHFR), fibrinogen (FI), plasminogen activator inhibitor (PAI-1), and platelet fibrinogen receptor type IIIA (GPIIIA). The incidence of these markers and their role in thrombosis in such patients was investigated. Results. The study provided data on the incidence of hereditary thrombophilia markers in patients with PV. Statistically significant differences in the incidence of these markers and homocysteine level were found between patients with thrombosis and without them. Conclusion. The information about the hereditary thrombophilia markers presence may be useful for the prescription of adequate antiaggregant and anticoagulant therapy for PV patients. Further research in this field is justified and it will probably demonstrate the relevance of hereditary thrombophilia markers as prognostic factors for thrombotic complications risk assessment

Common and rare variant association analyses in amyotrophic lateral sclerosis identify 15 risk loci with distinct genetic architectures and neuron-specific biology

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with a lifetime risk of one in 350 people and an unmet need for disease-modifying therapies. We conducted a cross-ancestry genome-wide association study (GWAS) including 29,612 patients with ALS and 122,656 controls, which identified 15 risk loci. When combined with 8,953 individuals with whole-genome sequencing (6,538 patients, 2,415 controls) and a large cortex-derived expression quantitative trait locus (eQTL) dataset (MetaBrain), analyses revealed locus-specific genetic architectures in which we prioritized genes either through rare variants, short tandem repeats or regulatory effects. ALS-associated risk loci were shared with multiple traits within the neurodegenerative spectrum but with distinct enrichment patterns across brain regions and cell types. Of the environmental and lifestyle risk factors obtained from the literature, Mendelian randomization analyses indicated a causal role for high cholesterol levels. The combination of all ALS-associated signals reveals a role for perturbations in vesicle-mediated transport and autophagy and provides evidence for cell-autonomous disease initiation in glutamatergic neurons

Chronic Myeloid Leukemia: Long-Term Experience of Target Therapy

Background & Aims. Interpretation of key aspects of pathogenesis of chronic myeloid leukemia (CML) and development and introduction of target therapy have changed the prognosis of this once fatal disease dramatically. Results of numerous clinical trials demonstrated substantial superiority of tyrosine kinase inhibitors over previous therapy techniques. At the same time, clinical trials had limitations in patient enrollment, as well as treatment conditions and duration. The analysis of our clinical experience in CML target therapy (over the period from 2003 till 2015) is an important argument for introduction of novel drugs into routine clinical practice. The aim of the study is to analyze our own experience in CML target therapy and to compare our results with clinical trials data. Methods. Outpatient’s cards and case histories of CML patients treated in the Russian Scientific Research Institute of Hematology and Transfusiology over last 12 years were analyzed in this work. Published results of multi-center clinical trials evaluating the use of tyrosine kinase inhibitors in CML were used for a comparative analysis. The primary morbidity rate and the prevalence of CML, results of first and subsequent treatment lines were studied with assessment of survival rates, adverse events, and the nature of the response (hematologic, cytogenetic and molecular). Results. The experience in treatment of 208 CML patients was analyzed. The use of imatinib led to clinical and hematological remission (complete hematologic response) was achieved in 95 % of patients. The frequency of complete cytogenetic responses (CCyR) was 69 %, and that of major molecular responses (MMR) was 58 %. The overall 5-year survival (OS) was 86.4 %, the 10-years OS was 67.5 %. The use of nilotinib during the second line permitted to achieve CCyR in 61 % of patients, and the MMR in 55 % of cases. The two-year OS was 96 % and the 5-year OS was 68 %. CCyR and MMR were achieved in 50 % patients treated with dasatinib during the second line. As for the third line, CCyR was achieved in 50 % of patients and MMR in 25 %. In case of previous imatinib and nilotinib resistance, CCyR was observed only in 36 % of patients and MMR in 18 % of cases. During second-line dasatinib treatment, the 2-year OS was 85 %, and the 5-year OS was 51 %; as for the third line, the results were 75 % and 50 %, respectively. The range and rates of adverse events of the therapy, in general, corresponded to results of clinical trials. Conclusion. The use of tyrosine kinase inhibitors in treatment of CML permits to prolong patient’s life span and quality of life significantly. The use of nilotinib and dazatinib (in case of nilotinib intolerance and/or resistance) could be effective in most patients