Thrombopoietin Receptor Agonists in Treatment of Idiopathic Thrompocytopenic Purpura (Primary Immune Thrombocytopenia): Efficacy and Safety in Everyday Clinical Practice

Background & Aims. The use of thrombopoietin receptor agonists (aTPO-r) is a new approach to the treatment of patients with idiopathic thrompocytopenic purpura (ITP) irresponsive to other methods. Data on the efficacy and safety of aTPO-r outside the frames of clinical trials are limited. The aim of the study is to evaluate the efficacy of the therapy in the routine clinical practice as the second and subsequent lines of therapy, as well as the frequency and nature of complications of the treatment in chronic ITP patients. Methods. Data on 58 adult patients (median age: 56 years) with chronic ITP were retrospectively evaluated; 43 (74 %) of them were treated with romiplostim and 15 (26 %) patients received eltrombopag. Two or more lines of prior therapy were ineffective in 19 (33 %) patients (14 from the romiplostim group and 5 from the eltrombopag group). aTPO-r was prescribed and adjusted according to the prescription guidelines. The efficacy of the treatment was assessed based on the platelet response and the possibility of achieving a sustained response after discontinuation of the therapy. Hemorrhagic manifestations were classified according to the WHO bleeding scale. The safety assessment is conducted by identifying adverse events (AEs) and lab test abnormalities. Treatment-related adverse events was assessed according to the Common Terminology Criteria for Adverse Events (CTCAE) v3.0. Results. The therapy with aTPO-r was effective in 49 (84 %) patients, including 36 patients (84 %) treated with romiplostim and 13 patients (87 %) with eltrombopag. The median dose to maintain a response was 3.7 mg/kg and 44 mg, respectively. A stable remission was achieved in 4 patients after discontinuation of romiplostim and 1 patient after discontinuation of eltrombopag. aTPO-r resistance was diagnosed in 9 (16 %) patients: 7 (16 %) of them were from the romiplostim group and 2 (13 %) from the eltrombopag group. Complete arrest of bleeding was achieved in 43 (88 %) responders and its reduction to grade I was achieved in the remaining 6 (12 %) of them. The most frequent AEs of romiplostim therapy were headache, arthralgia and dermatitis; and the treatment with eltrombopag caused hepatotoxicity, headache, and nausea. The severity of events did not lead to complete discontinuation of the therapy in any case. Different types of thrombotic complications were diagnosed in 3 patients (5.2 %). Conclusion. The therapy with aTPO-r is an effective and safe method for the treatment of patients with chronic ITP in the second and subsequent lines of therapy

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

Low Dose Cytarabine and Cladribine for Treatment of Relapsed or Refractory Acute Myeloid Leukemia: Clinical Experience

Aim. The aim of this paper is to evaluate the effectiveness of low dose cytarabine (Ara-C) combined with cladribine for the treatment of relapsed or refractory acute myeloid leukemia (AML) and to determine clinical and lab factors associated with response to the therapy. Methods. Data of 10 patients aged 26–58 years (median 48 years) were analyzed. The diagnoses were de novo AML (7 patients), secondary AML (sAML) (2 patients) and refractory anemia with excess of blasts (RAEB-2) (1 patient). Four patients had primary refractory AML. Relapse was diagnosed in 3 patients. The induction scheme 7+3 was ineffective in patient with RAEB-2. There was no response to any kind of therapy in sAML patients. The treatment scheme under trial consisted of Ara-C 10–15 mg/m2 subcutaneously twice a day for 1–14 days and cladribine 5 mg/m2 intravenously once a day for 1–5 days. The course was repeated in case of at least two-fold decrease in bone marrow blasts level in a punctate versus baseline. Medical examination and maintenance therapy were performed in accordance with protocols approved by the clinic. Results. According to the protocol, the patients received 1–2 courses. Response was achieved in 5 patients: 2 patients achieved complete response (CR) and 3 achieved partial response (PR). The most common complication was hematologic toxicity. All patients received transfusions of blood components. No lethal outcomes were observed within 8 weeks. The duration of the response was 2 to 3 months. During this period of time, allogeneic stem cell transplantation was performed in 2 patients with CR; however, in one patient, the conditioning regimen began at the same time with the increase in blast cell count in the bone marrow. The search for unrelated donors of hematopoietic stem cells for 2 patients with CR was begun. The distinct features of all patients with CR and PR were the following factors: de novo AML, absence of FLT3 or c-KIT mutations and the course duration was not less than 10 days. Conclusion. Low dose Ara-C in combination with cladribine may be considered a treatment option for some patients with relapsed or refractory de novo AML

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