Richter transformation - retrospective treatment outcomes analysis in Polish Adult Leukemia Study Group.

Richter transformation (RT) is defined as developing an aggressive lymphoma in 2-10% of patients suffering from chronic lymphocytic leukemia (CLL). So far, no complex analysis of RT demographics and treatment outcomes has been performed in Poland. Thus, the retrospective analysis of 124 patients with RT from Polish hematology centers was designed. Ninety-nine patients with diffuse large B-cell lymphoma (DLBCL-RT) were identified. The median overall survival (OS) for DLBCL-RT was 17.3 months, while for Hodgkin lymphoma (HL-RT)-21.3 months. In multivariate analysis, the independent factors of worse OS for DLBCL-RT were: prior CLL therapy, ECOG stage ≥2, and elevated serum LDH activity. Patients who proceeded to hematopoietic stem cell transplantation (HSCT) achieved better results. The median OS in allogeneic HSCT recipients was not reached, while in autologous HSCT median OS was 51.3 months. In conclusion, our study represents the largest dataset of patients diagnosed with RT in Poland and confirms its dismal prognosis.

Therapeutic adherence and assessment of satisfaction patients with multiple myeloma treated with immunomodulatory drugs in a "real-world" study: Experiences of the Polish Myeloma Group.

INTRODUCTION: Therapeutic adherence (TA) is one of the most important factors influencing the effectiveness of treatment. Oral anti-cancer drugs are increasingly used to treat malignancy including multiple myeloma (MM). Our study aimed to determine TA of patients with MM treated with IMiDs, to identify TA risk factors, and to determine satisfaction with medical care during the treatment with IMiDs. METHODS: A cross-sectional survey-based study involving adult patients with MM treated with IMiDs. RESULTS: Between January 2021 and May 2021, 267 patients with MM were enrolled in the study. The dosing schedule was declared as easy by 71.8% of patients, as standard for 24.0%, and difficult for 4.2% of patients. During MM treatment, 85.0% of patients did not skip any IMiDs dose, and 87.6% did not skip the IMiDs dose in the last cycle of chemotherapy. Identified factors affecting TA included the treatment duration and education level. In addition, depending on the patient's well-being, gender, and household companionship influenced TA. Satisfaction with medical care during the treatment with IMiDs was declared by 95.5% of patients with MM. In our cohort, 95.5% of patients were satisfied with the information they received from the hematologist during treatment with IMiDs. CONCLUSIONS: Patients with MM treated with IMiDs are highly adherent to treatment. With time from the beginning of treatment, patients need more attention and motivation to adhere to the therapy rules.

Clinical efficacy and tolerability of venetoclax plus rituximab in patients with relapsed or refractory chronic lymphocytic leukemia-a real-world analysis of the Polish Adult Leukemia Study Group.

The results of the MURANO trial showed encouraging progression-free survival (PFS) and overall survival (OS) in relapsed/refractory chronic lymphocytic leukemia (RR-CLL) patients treated with venetoclax-rituximab (VEN-R). A retrospective analysis was performed to evaluate the efficacy and safety of VEN-R within the Polish Adult Leukemia Study Group (PALG) centers. The study group included 117 patients with RR-CLL (with early relapse after immunochemotherapy or bearing TP53 aberrations) treated with VEN-R in 2019-2023 outside clinical trials. Patients were treated with a median of 2 (range 1-9) previous lines of therapy. Twenty-two participants were previously treated with BTKi (18.8% out of 117). The median follow-up was 20.3 months (range 0.27-39.1). The overall response rate (ORR) was 95.3% in the group of patients in whom a response to treatment was assessed and 86.3% for all patients. Twenty patients (17.1% out of 117) achieved a complete response (CR), 81 (69.2%) achieved a partial response (PR), and in 5 patients (4.3%), disease progression was noted (assessed as the best response during treatment). The median PFS in the whole cohort was 36.97 (95% CI 24.5, not reached) months, and the median OS was not reached (95% CI 27.03, not reached). Thirty-six patients died during the follow-up, 10 (8.5%; 27.8% of deaths) due to COVID-19 infection. All grade neutropenia (n = 87/117, 74.4%; grade 3 or higher n = 67/117, 57.3%) was the most common treatment adverse event. Forty-five patients (38.5%) remained on treatment, and twenty-two (18.8%) completed 24 months of therapy, while it was discontinued in fifty cases (42.7%). In this real-world setting of early access in very high-risk RR-CLL patients, the VEN-R regimen was associated with shorter median PFS compared with the results of the MURANO trial. This outcome, however, could be attributed to patients' exposure to SARS-CoV-2 infection and the aggressive course of the disease as very high-risk patients, after multiple lines of prior therapies, were included in the Polish Ministry of Health reimbursement program.

Eculizumab treatment in pregnant women with paroxysmal nocturnal hemoglobinuria: A Polish experience.

BACKGROUND: Eculizumab is an antibody targeting the C5 complement protein. Clinical trials suggest that eculizumab significantly reduces transfusion requirements and prevents disease complications in patients with paroxysmal nocturnal hemoglobinuria (PNH). OBJECTIVES: To analyze the outcome of pregnancies among Polish women with PNH treated with eculizumab as a part of the Polish National Health Fund program. MATERIAL AND METHODS: We report the outcomes of 3 pregnancies among women treated with eculizumab between 2017 and 2020. For 1 of these woman, it was the 1st pregnancy, while the remaining 2 patients had previously had 1 previous successful pregnancy each. RESULTS: All 3 mothers survived pregnancy, and all children were born alive. One of the patients had a vaginal delivery. Another required cesarean delivery at the 34th week due to a decreasing platelet count. In 1 case, premature rupture of the fetal membranes occurred at week 36, followed by artificial labor induction. All children were born without any inborn defects. The 2 prematurely born babies required a prolonged hospital stay. CONCLUSION: Treatment with eculizumab seems to reduce the risk to a mother and a child associated with PNH. However, more data are necessary to confirm this notion.

Paroxysmal nocturnal hemoglobinuria: advances in the understanding of pathophysiology, diagnosis, and treatment.

In recent years, "old" paroxysmal nocturnal hemoglobinuria (PNH) has achieved new advances in terms of the understanding of its pathophysiology, modern approach to diagnostics, optimization of therapy, and dynamic development of new therapeutic agents. This review emphasizes the greater than previously recognized importance of the reduced susceptibility of PNH stem cells to apoptosis in the selection of a defective clone. Some changes in cytokine and chemokine profiles in patients with PNH have been interpreted in the context of autoimmunity and apoptosis. The classification of PNH presentations, characteristics of the functions of selected glycosylphosphatidylinositol-anchored proteins, as well as pathologies associated with hemolysis, thrombosis, and bone marrow failure are described. The current diagnostic process for various forms of PNH is presented in detail, as well as its importance in the choice of treatment and prognosis of the disease course. Determinants of modern treatment, such as strategies (complement C5 inhibitors vs hematopoietic stem cell allotransplantation), the safety and efficacy of treatment with eculizumab or ravulizumab, policy of initiation and monitoring of treatment, the criteria for response to treatment and final outcomes of treatment are described. Among the new therapeutic agents, crovalimab and C5 inhibitors at a less advanced stage of research are discussed: tesidolumab, pozelimab, zilucoplan, nomacopan, and cemdisiran. The first approved proximal complement pathway inhibitors that primarily prevent extravascular hemolysis, pegcetacoplan, danikopan, and iptacopan, are presented and their potential benefits are highlighted.

Persistent imbalance, anti-apoptotic, and anti-inflammatory signature of circulating C-C chemokines and cytokines in patients with paroxysmal nocturnal hemoglobinuria.

OBJECTIVE: Paroxysmal nocturnal hemoglobinuria (PNH) is a clonal non-malignant disease in which hematopoietic cell apoptosis may play an important pathophysiological role. Previous studies of the content of phosphatidylinositol (3,4,5)-trisphosphate (PI(3,4,5)P3) indicated the possibility of remote transmission of anti-apoptotic signals between pathological and normal hematopoietic progenitors. METHODS: The study determined the plasma levels of beta chemokines and cytokines in N = 19 patients with PNH and 31 healthy controls. The research material was peripheral blood plasma (EDTA) stored at -80 °C until the test. Beta chemokine and cytokine concentrations were tested in duplicate with Bio-Plex Pro Human Cytokine Assay (Bio-Rad, Hercules, CA, USA) using a Luminex 200 flow cytometer and xPONENT software (Luminex Corporation, Austin, TX, USA). In peripheral blood CD34+ cells we tested the proportions of PI(3,4,5)P3+ and Annexin binding apoptotic phenotype using FC and phosflow. RESULTS: Compared to the control group, the PNH group showed a significant increase in the plasma concentration of some beta chemokines and cytokines, including MIP-1alpha/CCL3, eotaxin/CCL11, MCP1/CCL2, IL4 and G-CSF. In the group of PNH patients, a significant decrease in the concentration of some cytokines was also observed: RANTES/CCL5, MIP-1beta/CCL4, PDGF-BB and IL9. At the same time, the plasma concentrations of the chemokine IP-10/CXCL10 and the cytokines IFN-gamma, TNF, IL6 and IL10 showed no significant deviations from the values for the control group. Anti-apoptotic phenotype and phosphatidylinositol (3,4,5)-trisphosphate content in PNH clone of CD34+ cells were associated with the level of CCL3 and negatively associated with CCL5, CCL4, PDGF-BB and IL9. CONCLUSIONS: This data suggest the existence of apoptotic and PI(3,4,5)P3 imbalance in PNH CD34+ cells driven by anti-apoptotic cytokine biosignature in PNH. Plasma cytokines and intracellular enzymes that regulate the phosphoinositide pathways may become a therapeutic target in PNH.

Cladribine Combined with Low-Dose Cytarabine as Frontline Treatment for Unfit Elderly Acute Myeloid Leukemia Patients: Results from a Prospective Multicenter Study of Polish Adult Leukemia Group (PALG).

Acute myeloid leukemia (AML) in older unfit patients is a therapeutic challenge for clinical hematologists. We evaluated the efficacy and safety of a novel low-intensity regimen consisting of low-dose cytarabine and cladribine (LD-AC+cladribine) in first-line treatment of elderly (≥60 years) AML patients not eligible for intensive chemotherapy (IC) who had either the Eastern Cooperative Oncology Group performance status (ECOG PS) ≥2 or the hematopoietic cell transplantation comorbidity index (HCT-CI) score ≥3. The induction phase included two cycles of LD-AC+cladribine. Patients who achieved at least partial remission (PR) received maintenance treatment with LD-AC alone. Overall, 117 patients with a median age of 70 years were enrolled. Adverse cytogenetics, ECOG PS ≥2 and HCT-CI score ≥3 was observed in 43.5%, 60%, and 58% of patients, respectively. The response rate (≥PR) was 54% (complete remission [CR], 32%; CR with incomplete hematologic recovery [CRi], 5%). A median overall survival (OS) was 21 and 8.8 months in CR/CRi and PR group, respectively. Advanced age (≥75 years) and adverse cytogenetics had a negative impact on OS. The 56-day mortality rate was 20.5%. In conclusion, LD-AC+cladribine is a beneficial therapeutic option with a predictable safety profile in elderly AML patients not eligible for IC.

Efficacy of high-dose corticosteroid-based treatment for chronic lymphocytic leukemia patients with p53 abnormalities in the era of B-cell receptor inhibitors.

PURPOSE: High-dose methylprednisolone (HDMP) with or without anti-CD20 antibody treatment in the pre B-cell receptor inhibitor (BCRi) era was used as potential salvage therapy for relapsed/refractory chronic lymphocytic leukemia/small lymphocytic lymphoma (r/r CLL/SLL) patients bearing the 17p deletion. PATIENTS AND METHODS: Outcomes were compared in retrospect between r/r patients treated with HDMP (n = 20), ibrutinib (n = 39) and idelalisib with rituximab (n = 14). RESULTS: Higher overall response rates were found in those patients undergoing BCRi therapy compared to HDMP (79.2% vs. 0%; p < 0.0001), along with longer median progression-free survival (not reached vs. 24.1 months; p < 0.01). Nevertheless, there were no differences in the overall survival (HDMP 35.87 months vs. not reached; p = 0.58). CONCLUSION: HDMP treatment was significantly inferior in terms of response rate and progression-free survival in r/r CLL/SLL patients with the 17p deletion, and may only be used whenever novel compounds are unavailable.

Long-term Efficacy of Ibrutinib in Relapsed or Refractory Chronic Lymphocytic Leukemia: Results of the Polish Adult Leukemia Study Group Observational Study.

BACKGROUND/AIM: To study the long-term clinical efficacy and tolerability of ibrutinib monotherapy in real-world relapsed and refractory chronic lymphocytic leukemia (RR-CLL) patients outside clinical trials. PATIENTS AND METHODS: Clinical data of 171 RR-CLL patients treated with ibrutinib were collected within the observational study of the Polish Adult Leukemia Study Group. RESULTS: Median patient age was 64 years. Patients were pretreated with 3 (1-10) median lines of therapy, while 42 (24.6%) had 17p deletion. The median observation time was 40 months (range=1-59 months), while median ibrutinib monotherapy reached 37.5 months (range=0.4-59.2 months). Response was noted in 132 (77.2%) patients. The estimated 5-year progression-free survival (PFS) and overall survival (OS) rates were 61.1% (95%CI=49.3-70.9%) and 56.8% (95%CI=45.6-66.6%), respectively. At the time of analysis 97 (56.7%) remained under ibrutinib monotherapy. CONCLUSION: Ibrutinib is clinically effective and tolerable as a monotherapy in real-world RR-CLL patients.

Comparable Efficacy of Idelalisib Plus Rituximab and Ibrutinib in Relapsed/refractory Chronic Lymphocytic Leukemia: A Retrospective Case Matched Study of the Polish Adult Leukemia Group (PALG).

BACKGROUND/AIM: There is limited amount of data available on the comparative efficacy of ibrutinib and idelalisib, the B-cell receptor inhibitors (BCRi) newly approved for relapsed/refractory chronic lymphocytic leukemia/small lymphocytic lymphoma (r/r CLL/SLL) treatment. The aim of our study was to analyze and compare the outcomes of real-world r/r CLL/SLL patients treated with these two BCRi in outside clinical trials. PATIENTS AND METHODS: A comparative case matched 1:2 analysis was performed on idelalisib combined with rituximab and ibrutinib efficacy in 102 patients with r/r CLL/SLL from two observational studies of the Polish Adult Leukemia Group (PALG). RESULTS: Both therapies produced similar overall response rates (idelalisib plus rituximab 76.4% and ibrutinib 72.1%). Median progression-free survival (PFS) and overall survival (OS) in both groups were not reached. Furthermore, no significant difference was observed between both BCRi regimens in regard to PFS (HR=0.75, 95% CI=0.30-1.86, p=0.55) and OS (HR=0.65, 95%CI=0.26-1.68, p=0.39). CONCLUSION: In summary, the results of this retrospective analysis suggest that idelalisib combined with rituximab and ibrutinib therapies have comparable activity in r/r CLL/SLL in daily clinical practice.

Microenvironment-induced PIM kinases promote CXCR4-triggered mTOR pathway required for chronic lymphocytic leukaemia cell migration.

Lymph node microenvironment provides chronic lymphocytic leukaemia (CLL) cells with signals promoting their survival and granting resistance to chemotherapeutics. CLL cells overexpress PIM kinases, which regulate apoptosis, cell cycle and migration. We demonstrate that BCR crosslinking, CD40 stimulation, and coculture with stromal cells increases PIMs expression in CLL cells, indicating microenvironment-dependent PIMs regulation. PIM1 and PIM2 expression at diagnosis was higher in patients with advanced disease (Binet C vs. Binet A/B) and in those, who progressed after first-line treatment. In primary CLL cells, inhibition of PIM kinases with a pan-PIM inhibitor, SEL24-B489, decreased PIM-specific substrate phosphorylation and induced dose-dependent apoptosis in leukaemic, but not in normal B cells. Cytotoxicity of SEL24-B489 was similar in TP53-mutant and TP53 wild-type cells. Finally, inhibition of PIM kinases decreased CXCR4-mediated cell chemotaxis in two related mechanisms-by decreasing CXCR4 phosphorylation and surface expression, and by limiting CXCR4-triggered mTOR pathway activity. Importantly, PIM and mTOR inhibitors similarly impaired migration, indicating that CXCL12-triggered mTOR is required for CLL cell chemotaxis. Given the microenvironment-modulated PIM expression, their pro-survival function and a role of PIMs in CXCR4-induced migration, inhibition of these kinases might override microenvironmental protection and be an attractive therapeutic strategy in this disease.

Rituximab, cladribine, and cyclophosphamide (RCC) induction with rituximab maintenance in chronic lymphocytic leukemia: PALG - CLL4 (ML21283) trial.

OBJECTIVES: PALG CLL4 is the first, randomized, phase IIIb study with rituximab, cladribine, and cyclophosphamide (RCC) induction and subsequent maintenance with rituximab in previously untreated chronic lymphocytic leukemia (CLL) patients. METHODS: The induction treatment consisted of 6 RCC cycles regimen. Patients with complete response (CR) or partial response (PR) after an induction phase were randomized into a maintenance arm with rituximab or an observational arm. RESULTS: In the intention-to-treat population, 97 patients completed the induction phase with an overall response rate (ORR) of 73.2% (CR 22.7%, PR 50.5%). Subsequently, 66 patients were randomized into the rituximab maintenance arm (n = 33) or the observational arm (n = 33). CR rates were 57.1% in the maintenance group vs 50% in the observational group. PFS was significantly longer in the rituximab maintenance vs the observational arm (P = .028). The multivariate Cox model indicated that del17p (P = .006) and elevated beta-2-microglobulin (P = .015) significantly increased the hazard ratio (HR) of progression, whereas the presence of CD38 (P = .013) significantly decreased it; maintenance therapy with rituximab (P < .0001) significantly decreased the HR of disease progression. CONCLUSIONS: The study confirmed the high efficacy and acceptable safety profile of induction therapy with RCC and maintenance therapy with rituximab in previously untreated patients with CLL.

Addition of cladribine to the standard induction treatment improves outcomes in a subset of elderly acute myeloid leukemia patients. Results of a randomized Polish Adult Leukemia Group (PALG) phase II trial.

Intensive induction chemotherapy using anthracycline and cytarabine backbone is considered the most effective upfront therapy in physically fit older patients with acute myeloid leukemia (AML). However, outcomes of the standard induction in elderly AML are inferior to those observed in younger patients, and they are still unsatisfactory. As addition of cladribine to the standard induction therapy is known to improve outcome in younger AML patients. The present randomized phase II study compares efficacy and toxicity of the DAC (daunorubicin plus cytarabine plus cladribine) regimen with the standard DA (daunorubicin plus cytarabine) regimen in the newly diagnosed AML patients over 60 years of age. A total of 171 patients were enrolled in the study (DA, 86; DAC, 85). A trend toward higher complete remission (CR) was observed in the DAC arm compared to the DA arm (44% vs. 34%; P = .19), which did not lead to improved median overall survival, which in the case of the DAC group was 8.6 months compared to in 9.1 months in the DA group (P = .64). However, DAC appeared to be superior in the group of patients aged 60-65 (CR rate: DAC 51% vs. DA 29%; P = .02). What is more, a subgroup of patients, with good and intermediate karyotypes, benefited from addition of cladribine also in terms of overall survival (P = .02). No differences in hematological and nonhematological toxicity between the DA and DAC regimens were observed.

Treatment of elderly patients with acute myeloid leukemia adjusted for performance status and presence of comorbidities: a Polish Adult Leukemia Group study.

This prospective study estimated outcomes in 509 elderly patients with acute myeloid leukemia (AML) with different treatment approaches depending on Eastern Cooperative Oncology Group (ECOG) performance status and Charlson Comorbidity Index (CCI). Patients were stratified into fit (ECOG 0-2 and CCI 0-2) or frail (ECOG>2 and/or CCI>2) groups. Fit patients with CCI 0 received intensive chemotherapy whilst reduced-intensive chemotherapy (R-IC) was given to those with CCI 1-2. Frail patients received best supportive therapy. Fit patients presented a longer overall survival (OS) than frail subjects, but 8-week mortality rates were similar. The complete response (CR) rate between fit CCI 0 and CCI 1-2 subgroups was significantly different. Both of the fit subgroups showed similar 8-week mortality rates and OS probabilities. Allocating fit patients with CCI 1-2 to R-IC enabled an increase in the group of elderly patients who could be treated with the intention of inducing remission.

Cytotoxicity of purified listeriolysin O on mouse and human leukocytes and leukaemia cells.

BACKGROUND: Listeriolysin O (LLO) is the main virulence factor of Listeria monocytogenes and facilitates the intracellular survival of the pathogen. Some of its characteristics endorse the growing popularity of LLO for use in biotechnology, particularly in the development of novel vaccines. Here, we evaluate the use of LLO to eradicate leukaemia cells. RESULTS: A purified LLO preparation was obtained by affinity chromatography. The LLO preparation procedure was optimized and purified LLO was tested for optimal conditions of storage including temperature, application of proteinase inhibitors and serum components. We demonstrated the possibility of regulating LLO activity by adjusting cell membrane cholesterol content. The LLO preparation had haemolytic activity and had a cytotoxic effect on the human T-leukaemia Jurkat cell line as well as mouse and human peripheral blood mononuclear cells. CONCLUSIONS: LLO has a very potent cytotoxic activity towards human leukocytes. Importantly, the cytotoxic activity was easily regulated in vitro and could be restricted to areas containing malignant cells, raising the possibility of future clinical application of LLO for leukaemia treatment.