Fluorescent Activity-Based Probe To Image and Inhibit Factor XIa Activity in Human Plasma.

Anticoagulation therapy is a mainstay of the treatment of thrombotic disorders; however, conventional anticoagulants trade antithrombotic benefits for bleeding risk. Factor (f) XI deficiency, known as hemophilia C, rarely causes spontaneous bleeding, suggesting that fXI plays a limited role in hemostasis. In contrast, individuals with congenital fXI deficiency display a reduced incidence of ischemic stroke and venous thromboembolism, indicating that fXI plays a role in thrombosis. For these reasons, there is intense interest in pursuing fXI/factor XIa (fXIa) as targets for achieving antithrombotic benefit with reduced bleeding risk. To obtain selective inhibitors of fXIa, we employed libraries of natural and unnatural amino acids to profile fXIa substrate preferences. We developed chemical tools for investigating fXIa activity, such as substrates, inhibitors, and activity-based probes (ABPs). Finally, we demonstrated that our ABP selectively labels fXIa in the human plasma, making this tool suitable for further studies on the role of fXIa in biological samples.

Novel Variant of the SLC4A1 Gene Associated with Hereditary Spherocytosis.

Hereditary spherocytosis (HS) refers to the group of the most frequently occurring non-immune hereditary hemolytic anemia in people of Caucasian central or northern European ancestry. HS is mainly associated with pathogenic variants of genes encoding defects in five membrane proteins, including anion exchanger 1 encoded by the SLC4A1 gene. In this study, in a family affected with HS, we identified a hitherto unreported AE1 defect, variant p.G720W. The result of it is most likely the HS phenotype. Molecular dynamics simulation study of the AE1 transmembrane domain may indicate reasonable changes in AE1 domain structure, i.e., significant displacement of the tryptophan residue towards the membrane surface connected with possible changes in AE1 function. The WES analysis verified by classical sequencing in conjunction with biochemical analysis and molecular simulation studies shed light on the molecular mechanism underlying this case of hereditary spherocytosis, for which the newly discovered AE1 variant p.G720W seems crucial.

Parallel imaging of coagulation pathway proteases activated protein C, thrombin, and factor Xa in human plasma.

Activated protein C (APC), thrombin, and factor (f) Xa are vitamin K-dependent serine proteases that are key factors in blood coagulation. Moreover, they play important roles in inflammation, apoptosis, fibrosis, angiogenesis, and viral infections. Abnormal activity of these coagulation factors has been related to multiple conditions, such as bleeding and thrombosis, Alzheimer's disease, sepsis, multiple sclerosis, and COVID-19. The individual activities of APC, thrombin, and fXa in coagulation and in various diseases are difficult to establish since these proteases are related and have similar substrate preferences. Therefore, the development of selective chemical tools that enable imaging and discrimination between coagulation factors in biological samples may provide better insight into their roles in various conditions and potentially aid in the establishment of novel diagnostic tests. In our study, we used a large collection of unnatural amino acids, and this enabled us to extensively explore the binding pockets of the enzymes' active sites. Based on the specificity profiles obtained, we designed highly selective substrates, inhibitors, and fluorescent activity-based probes (ABPs) that were used for fast, direct, and simultaneous detection of APC, thrombin, and fXa in human plasma.

St. Thomas Modified Cardioplegia Effects on Myoblasts' Viability and Morphology.

Background and Objectives: The cardioplegic arrest of the heart during cardiosurgical procedures is the crucial element of a cardioprotection strategy. Numerous clinical trials compare different cardioplegic solutions and cardioprotective protocols, but a relatively small number of papers apply to in vitro conditions using cultured cells. This work aimed to analyze whether it is possible to use the rat heart myocardium cells as an in vitro model to study the protective properties of St. Thomas cardioplegia (ST2C). Methods: The rat heart myocardium cells-H9C2 were incubated with cold cardioplegia for up to 24 h. After incubation, we determined: viability, confluency, and cell size, the thiol groups' level by modifying Ellman's method, Ki67, and Proliferating Cell Nuclear Antigen expression (PCNA). The impact on cells' morphology was visualized by the ultrastructural (TEM) study and holotomograpic 3D imaging. Results: The viability and confluency analysis demonstrated that the safest exposure to ST2C, should not exceed 4h. An increased expression of Ki67 antigen and PCNA was observed. TEM and 3D imaging studies revealed vacuolization after the longest period of exposure (24). Conclusions: According to obtained results, we conclude that STC can play a protective role in cardiac surgery during heart arrest.

Curcumin Loaded Nanocarriers with Varying Charges Augmented with Electroporation Designed for Colon Cancer Therapy.

(1) Background: The size and surface charge are the most significant parameters of nanocarriers that determine their efficiency and potential application. The poor cell uptake of encapsulated drugs is the main limitation in anticancer treatment. The well-defined properties of nanocarriers will enable to target specific tissue and deliver an active cargo. (2) Methods: In the current study, poly(D,L -lactide) (PLA) nanocarriers loaded with curcumin (CUR) and differing surface charge were evaluated for transport efficacy in combination with electroporation (EP) in dependence on the type of cells. The obtained CUR-loaded nanoparticles with diameters ranging from 195 to 334 nm (derived from dynamic light scattering (DLS)) were characterized by atomic force microscopy (AFM) (morphology and shape) and Doppler electrophoresis (ζ-potential) as well as UV-vis spectroscopy (CUR encapsulation efficiency (about 90%) and photobleaching rate). The drug delivery properties of the obtained PLA nanocarriers enhanced by electroporation were assessed in human colon cancer cells (LoVo), excitable normal rat muscle cells (L6), and free of voltage-gated ion channels cells (CHO-K1). CLSM studies, viability, and ROS release were performed to determine the biological effects of nanocarriers. (3) Results: The highest photodynamic activity indicated anionic nanocarriers (1a) stabilized by C12(COONa)2 surfactant. Nanocarriers were cytotoxic for LoVo cells and less cytotoxic for normal cells. ROS release increased in cancer cells with the increasing electric field intensity, irradiation, and time after EP. Muscle L6 cells were less sensitive to electric pulses. (4) Conclusions: EP stimulation for CUR-PLA nanocarriers transport was considered to improve the regulated and more effective delivery of nanosystems differing in surface charge.

What factors determine the pregnancy outcome in patients with essential thrombocythemia?

Objectives: Treatment of essential thrombocythemia (ET) is particularly challenging in pregnancy due to the increased risk of thromboembolic complications. Therefore, the use of antithrombotic regimens are recommended in pregnant women with ET.Methods: The study included 52 pregnancies in 27 patients diagnosed with ET, who were treated in Department of Haematology. The influence of anticoagulant, antiplatelet and cytoreductive therapy on the course and outcome of pregnancy was analysed. This study also examined if there was any correlation between molecular and clinical features such as mutational profile, blood count, presence of acquired von Willebrand syndrome (AvWS), the International Prognostic Score for Essential Thrombocythemia (IPSET) risk group and the IPSET-thrombosis risk group and pregnancy outcome.Results: Study participants who received antithrombotic therapy were significantly more likely to give birth to a healthy child. The best outcomes were observed in patients who received low dose acetylsalicylic acid (ASA) together with low-molecular-weight heparin (LMWH). There was a statistically significant correlation between classification to the high-risk group according to the IPSET-thrombosis score and incidence of miscarriage. Cytoreductive treatment with interferon-α2, as well as the presence of AvWS did not increase the likelihood of pregnancy loss. Blood counts and presence of specific gene mutations profile were also not found to be significant determinants of pregnancy outcome.Conclusion: To our best knowledge, this is the first clinical study investigating the correlation between risk group (according to IPSET and IPSET-thrombosis) and pregnancy outcome in women with ET.

Germline mutations among Polish patients with acute myeloid leukemia.

BACKGROUND: A small but important proportion of patients (4-10 %) with AML have germline mutations. They can cause the development of AML at an earlier age, confer a higher risk of relapse or predispose to secondary leukemias, including therapy-related leukemias. The analysis of germline mutations in a patient and his/her family is also critical for the selection of suitable family donors if the patient is a candidate for hematopoietic stem cell transplantation (HSCT). METHODS: 103 unrelated consecutive patients with de novo AML were enrolled in the study. Control group consisted of 103 persons from the general population. We performed NGS sequencing of bone marrow cells and buccal swabs DNA of six genes: CEBPA, DDX41, ETV6, TERT, GATA2, and IDH2 to detect germline pathogenic mutations. RESULTS: In the investigated group, 49 variants were detected in six genes. 26 of them were somatic and 23 germline. Germline variants were detected in all six tested genes. Eight pathogenic germline mutations were detected in 7 AML patients, in three genes: CEBPA, ETV6, and IDH2. One patient had two pathogenic germinal mutations, one in ETV6 and one in CEBPA gene. We identified one novel pathogenic germline mutation in CEBPA gene. The difference in frequency of all pathogenic germline mutations between the tested (7.77 %) and control groups (0.97 %) was statistically significant (p = 0.046). In the tested group, the median age at AML diagnosis was 11 years lower in patients with pathogenic germline mutations than in patients without them (p = 0.028). CONCLUSIONS: We showed higher frequency of CEBPA, ETV6, and IDH2 germline mutations in AML patients than in control group, which confirms the role of these mutations in the development of AML. We also showed that the median age at the onset of AML in patients with pathogenic germline mutations is significantly lower than in patients without them.

Identification of a Novel Mutation of ß-Spectrin in Hereditary Spherocytosis Using Whole Exome Sequencing.

Hereditary spherocytosis (HS), the most commonly inherited hemolytic anemia in northern Europeans, comprises a group of diseases whose heterogeneous genetic basis results in a variable clinical presentation. High-throughput genome sequencing methods have made a leading contribution to the recent progress in research on and diagnostics of inherited diseases and inspired us to apply whole exome sequencing (WES) to identify potential mutations in HS. The data presented here reveal a novel mutation probably responsible for HS in a single Polish family. Patients with clinical evidence of HS (clinical symptoms, hematological data, and EMA test) were enrolled in the study. The examination of the resulting WES data showed a number of polymorphisms in 71 genes associated with known erythrocyte pathologies (including membranopathies, enzymopathies, and hemoglobinopathies). Only a single SPTB gene variant indicated the possible molecular mechanism of the disease in the studied family. The new missense mutation p.C183Y was identified using WES in the SPTB gene, which is most likely the cause of clinical symptoms typical of hereditary spherocytosis (membranopathy) due to structural and functional impairments of human ß-spectrin. This mutation allows for a better understanding of the molecular mechanism(s) of one of the membranopathies, hereditary spherocytosis.

Searching for germline mutations in the RUNX1 gene among Polish patients with acute myeloid leukemia.

The aim of the study was the identification of constitutional RUNX1 mutations among AML patients. The study group included 100 patients of Polish origin, diagnosed with de novo AML. 14 out of 100 AML patients had together 17 RUNX1 mutations, three of which were found to be germline changes. The difference in germline mutation frequency between study and control groups was not statistically significant (p = 0.193), but the odds ratio was 7.215. In all patients with germline mutations, chromosome 7 aberrations were found. The difference in the frequency of chromosome 7 aberrations between the group of patients with and without germline mutations was statistically significant (p = 0.008, OR = 73.00). We showed a higher frequency of germline mutations of RUNX1 in AML patients than in the control group, which confirms the role of these mutations in the development of AML, and an association of germline mutations with aberrations of chromosome 7.

Primary refractory multiple myeloma: a real-world experience with 85 cases.

This study determined whether 85 patients with multiple myeloma (MM) double-refractory to primary induction therapy with triplet regimens had a homogenous prognosis. The overall response rate (ORR) after the second-line therapy was 51%. Patients who proceeded to immediate autologous stem cell transplantation (ASCT) had better ORR than those who received conventional therapies (62% vs. 31%). The ORR for patients who had ASCT directly after the frontline therapy was higher than for those treated with other regimens as the second line therapy (91% vs. 45%) and offered ASCT as the third-line therapy (91% vs. 55%). The median progression-free survival (PFS) after the second-line therapy and median overall survival were 21.6 months and 35.6 months, respectively. ASCT after the second line treatment (HR = 0.24) was an independent predictor of PFS. Eligible patients with primary refractory MM achieve the most benefit from ASCT, also performed immediately after first line induction therapy.

Safety and Efficacy of Bendamustine Monotherapy in the First-Line Treatment of Patients with Chronic Lymphocytic Leukemia: Polish Lymphoma Research Group Real-Life Analysis.

Bendamustine is a cytostatic drug with a unique structure, combining the features of purine nucleoside analogs and alkylating agents. In patients with chronic lymphocytic leukemia (CLL) it is commonly used in combination with rituximab (BR protocol) both in the first-line as well as subsequent lines of therapy, and in clinical trials it is often combined with new targeted therapies. Therefore, the data on its real-life safety and efficacy are of clinical significance. As the Polish Lymphoma Research Group (PLRG), we retrospectively analyzed the efficacy and tolerability of bendamustine monotherapy in 96 patients with CLL. The median number of bendamustine cycles was 5, and 44 patients did not complete the planned 6 cycles (46%). Among the adverse events associated with the earlier termination of bendamustine treatment, infections were the most common (20.5%), followed by neutropenia (15.9%) and thrombocytopenia (15.9%). Dose reductions and/or delays occurred in 31% of treatment cycles (132 of 425) with neutropenia (17.9%) as the most frequent cause. Efficacy analysis showed an overall response rate of 88.2% with complete remission and partial remission achieved in 43.8 and 41.7% of patients, respectively. At the 24th month of follow-up, progression-free survival was 52% and overall survival was 69.7%. Bendamustine in monotherapy was found to be safe and efficacious, at least in terms of early response. Special attention should be paid to infectious complications, and especially that immune disorders are characteristic in the clinical course of CLL. Our observations suggest efforts must be made to ensure the proper timing and proper dose in the administration of the drug, and to avoid the premature termination of the treatment.

Expression of the PIM2 gene is associated with more aggressive clinical course in patients with chronic lymphocytic leukemia.

BACKGROUND: The PIM2 gene belongs to the PIM family, which encodes serine/threonine kinases involved in cell survival and apoptosis. The relation between the expression of the PIM2 gene and the course of chronic lymphocytic leukemia (CLL) has not been fully determined. OBJECTIVES: The aim of the study was to evaluate the role of the PIM2 gene as a marker of CLL malignancy and its importance as a predictive and prognostic factor. MATERIAL AND METHODS: Sixty-seven patients, 35 females and 32 males, aged 49-90 years, with de novo CLL, and 14 healthy individuals were enrolled in the study. Expression of the PIM2 gene was analyzed using TaqMan RQ-PCR assay and western blot test. RESULTS: Median PIM2 gene expression in CLL patients was higher than in controls. Patients with high expression of the PIM2 gene had shorter progression-free survival and time to first treatment than patients with low PIM2 expression. It was found that patients with CR had lower expression of the PIM2 gene than patients without complete remission (CR). Notably, associations between high PIM2 expression and rapid lymphocyte doubling time, the percentage of malignant lymphocytes with ZAP70 expression and the Rai stage were revealed. CONCLUSIONS: We found that the PIM2 gene is associated with a more aggressive clinical course of CLL.

Primary Intraocular Diffuse Large B-cell Lymphoma: Diagnostic Difficulties in Deep Retinal Infiltrations with Vitritis.

PURPOSE: Primary intraocular lymphoma (PIOL) is a rare malignancy with an aggressive clinical course. It is usually considered as a subset of primary central nervous system lymphoma. Differential diagnosis should include infectious and non-infectious aetiologies, particularly the common masqueraders sarcoidosis, tuberculosis, viral retinitis and syphilis. PATIENT: The article presents a case of bilateral vitreoretinal lymphoma manifesting as uveitis and vitritis resistant to corticosteroid therapy. The final diagnosis was based on a retinal biopsy. RESULTS: The patient was successfully treated with systemic and local therapy. Long-term complete remission (CR) was reached. The relapse of diffuse large B-cell lymphoma was revealed in the frontal left lobe after 48 months of CR duration. CONCLUSION: The diagnosis of PIOL is always very difficult. Cooperation of pathologists, ophthalmologists and hematologists is required for a quick and accurate diagnosis. Local and systemic treatment is needed to achieve CR, but the relapse rate remains very high.

Interesting coincidence of atypical TSH-secreting pituitary adenoma and chronic lymphocytic leukemia.

Thyrotropin-secreting adenomas (TSH-oma) are very rare pituitary tumours. They are macroadenomas usually presenting with signs and symptoms of hyperthyroidism, and mass effects. They can co-secrete other hormones such as growth hormone or prolactin. Different malignancies, including haematological ones, are reported in patients with pituitary diseases. Chronic lymphocytic leukemia (CLL) occurs mostly in older patients, more often in males. CLL is associated with increased risk of second malignancies such as other blood neoplasms, skin and solid tumours. We present a successful neurosurgical outcome in a patient with an interesting coincidence of atypical TSH-oma and asymptomatic CLL.

Case-adjusted bortezomib-based strategy in routine therapy of relapsed/refractory multiple myeloma shown to be highly effective--a report by Polish Myeloma Study Group.

The observational study was aimed at evaluating response, survival and toxicity of bortezomib-based, case-adjusted regimens in real-life therapy of 708 relapsed/refractory MM patients. Bortezomib was combined with anthracyclines, steroids, thalidomide, alkylators or given in monotherapy. The ORR was 67.9% for refractory and 69.9% for relapsed MM. The median PFS was 14 months and OS 57 months. Patients responding to the therapy had the probability of a 4-year OS at 67.0%. No toxicity was noted in 33.1% of patients. Severe events (grade 3/4) were reported in 35.9% of patients: neurotoxicity (16.7%), neutropenia (9.2%), thrombocytopenia (8.5%), and infections (6.5%). Bortezomib-based, case-adjusted regimens are in real-life practice effective in salvage therapy offering reliable survival with acceptable toxicity for relapsed/refractory MM patients.

Long-term results of the Polish Adult Leukemia Group PALG-CLL2 phase III randomized study comparing cladribine-based combinations in chronic lymphocytic leukemia.

Long-term outcomes following newer therapies for chronic lymphocytic leukemia (CLL) have rarely been reported. This article presents the results of the final analysis of the Polish Adult Leukemia Group PALG-CLL2 study performed 10 years from final patient enrollment. With the extended follow-up time, it was found that cladribine (2-CdA)-based combinations CMC (2-CdA, cyclophosphamide, mitoxantrone) and CC (2-CdA, cyclophosphamide) administered as first-line treatment of progressive CLL resulted in significantly longer progression-free survival, but similar overall survival compared to 2-CdA monotherapy. Furthermore, the risk of potentially fatal late adverse events including infections, autoimmune complications and, particularly, secondary neoplasms was comparable among patients treated with CMC, CC or 2-CdA. The results of our analysis support the importance of long-term outcome monitoring of randomized trials in CLL.

Immune thrombocytopenia in patients with chronic lymphocytic leukemia treated with cladribine-based regiments or chlorambucil--follow-up of PALG-CLL randomized trials.

OBJECTIVES: The relationship between treatments of chronic lymphocytic leukemia (CLL) with cladribine (2-CdA) or chlorambucil and immune thrombocytopenia (IT) has not been yet determined. METHODS: The records of 777 patients in two randomized Polish Adult Leukemia Group (PALG)-CLL programs treated with these agents were retrospectively analyzed. RESULTS: Immune thrombocytopenia occurred in 55 of 777 (7.1%) patients. No significant differences in IT prevalence were seen between patients on chlorambucil or 2-CdA-based regiments (P = 0.33). IT developed at a median time of 0.499 yr (0.06-4.8) from the start of CLL therapy. This time was significantly longer in patients treated with chlorambucil (2.03 yr, 95% CI: 0.06-4.22) in relation to patients treated with 2-CdA-based regiments (0.52 yr, 95%CI: 0.34-0.69, P = 0.049). Overall survival (OS) of patients with IT and those without IT were similar (2.65 yr vs. 3.2 yr P = 0.23) but the severity of bleeding was more pronounced in the 2-CdA group. The responses to IT therapy were 35%, 54% and 75% for steroids, chemotherapy and splenectomy, respectively. CONCLUSIONS: In this study, an unexpectedly high percentage of IT incidence was demonstrated in patients with CLL requiring chemotherapy. Although no marked differences were seen in IT frequency in patients treated with 2-CdA-based regiments compared to chlorambucil regimen, the clinical course of hemorrhagic diathesis was more severe in 2-CdA group. Also, the time elapsed from study screening to IT diagnosis was significantly shorter in the 2-CdA group than in the chlorambucil group suggesting a causative relationship. The appearance of IT did not influence the median time of OS.

Variations in suppressor molecule ctla-4 gene are related to susceptibility to multiple myeloma in a polish population.

Various phenotype and functional T-cell abnormalities are observed in multiple myeloma (MM) patients. The aim of this study was to investigate the association between polymorphisms in the gene encoding cytotoxic T-lymphocyte antigen-4 (CTLA-4), a negative regulator of the T-lymphocyte immune response and susceptibility to multiple myeloma in a Polish population. Two hundred MM patients and 380 healthy subjects were genotyped for the following polymorphisms: CTLA-4c.49A>G, CTLA-4g.319C>T, CTLA-4g.*642AT(8_33), CT60 (CTLA-4g.*6230G>A), Jo31 (CTLA-4g.*10223G>T). Our study is the largest and most comprehensive evaluation to date of the association between genetic polymorphisms in the CTLA-4 molecule and multiple myeloma. It was found that CTLA-4c.49A>G[G], CT60[G], and Jo31[G] alleles were more frequently observed in MM patients than in controls (0.50 vs. 0.44, p = 0.03, 0.65 vs. 0.58, p = 0.04, and 0.63 vs. 0.57, p = 0.03, respectively). Moreover, the haplotype CTLA-4c.49A>G[G], CTLA-4g.319C>T[C], CTLA-4g.*642AT(8_33) [8], CT60[G], Jo31[G] including all susceptibility alleles increases the risk of MM about fourfold (OR: 3.79, 95%CI: 2.08-6.89, p = 0.00001). These findings indicate that genetic variations in the CTLA-4 gene play role in susceptibility to multiple myeloma and warrant further investigation through replication studies.

[Thalidomide-induced sensory neuropaty in patients with multiple myeloma]. / Neuropatia czuciowa u chorych na szpiczaka mnogiego leczonych talidomidem.

UNLABELLED: Chemotherapy-induced sensory neuropathies differ in clinical picture. There is predominance of paresthesiae in some of them while in others pain or deep sensation failure can dominate. THE AIM OF THE STUDY: To perform the clinical and electrophysiological assessment of peripheral sensory nerves in patients with multiple myeloma (m.m.) treated with thalidomide. Special attention was directed to function of subtypes of sensory fibres which convey different modalities of sensation. MATERIAL AND METHODS: Twenty seven m.m. patients and 30 controls were examined. Neurological examination together with allocation to different groups acc. to sNCI-CTC scale were performed. Standard sensory conduction velocity was measured in ulnar and sural nerves. Quantitative Sensory Testing (QST) was used to determine thermal detection thresholds. RESULTS: All patients informed about subjective positive sensory symptoms and sensory deficit of symmetrical, distal pattern was found in them. Electroneurography revealed axonal and demyelinating abnormalities with dominance of axonal injury. Warm and heat-pain detection thresholds were elevated, while threshold for skin cooling was decreased both in palm and foot in m.m. patients in comparison with controls. There were no differences in the thresholds for cold-pain detection between examined groups. CONCLUSIONS: Thalidomide-induced sensory neuropathy can appear shortly after the introduction of treatment. Patients with longer duration of treatment or with higher cumulative dose present higher degree of neuropathy acc. to the sCNI-CTC scale. Sensory deficit in thalidomide' neuropathy is associated with dysfunction in A delta and C caliber primary afferent fibres.

Comparison of cladribine plus cyclophosphamide with fludarabine plus cyclophosphamide as first-line therapy for chronic lymphocytic leukemia: a phase III randomized study by the Polish Adult Leukemia Group (PALG-CLL3 Study).

PURPOSE Little is known about comparison of the activity of different purine nucleoside analogs in chronic lymphocytic leukemia (CLL). We conducted a randomized phase III trial to compare efficacy and safety of cladribine and fludarabine, each combined with cyclophosphamide, in previously untreated progressive CLL. PATIENTS AND METHODS Patients received cladribine at 0.12 mg/kg combined with cyclophosphamide at 250 mg/m(2) for 3 days intravenously (CC regimen) or fludarabine at 25 mg/m(2) combined with cyclophosphamide at 250 mg/m(2) for 3 days intravenously (FC regimen), every 28 days for up to six cycles. The primary end point was complete response (CR) rate. Secondary end points included overall response rate (ORR), progression-free survival (PFS), overall survival (OS), and treatment-related toxicity. RESULTS Of 423 randomly assigned patients (211 to CC and 212 to FC), 395 were evaluated in the final analysis. The CR and ORR reached 47% and 88% in the CC arm and 46% and 82% in the FC arm (P = .25 and P = .11, respectively). The median PFS was 2.34 years with CC and 2.27 years with FC (P = .51). OS and grade 3/4 treatment-related toxicity were also comparable. Moreover, we did not observe any significant differences in CC and FC efficacy across different patient prognostic subgroups that included patients with 17p13 (TP53 gene) deletion who had poor survival in both study arms. CONCLUSION Cladribine and fludarabine in combination with cyclophosphamide are equally effective and safe first-line regimens for progressive CLL. Both combinations have unsatisfactory activity in patients with 17p13 (TP53 gene) deletion.