Effect Of Cladribine Research Articles

Experience in the use of cladribine for the treatment of patients with highly active forms of multiple sclerosis in the Moscow region

To assess the efficacy and safety of cladribine in patients with highly active multiple sclerosis (MS) in the Moscow region. The analysis was based on data from 62 patients treated with cladribine between March 2021 and January 2024. The diagnosis of VAMS was confirmed in 51 patients, PPMS in 4 patients, and SPMS with exacerbations was diagnosed in 7 cases. Of these, 3 patients completely completed therapy more than a year ago, 20 people received 2 courses of the drug less than a year ago, 39 patients underwent 1 course of therapy. The effect of cladribine on reducing disease activity and progression, as well as the safety of therapy, was evaluated. After 1 course, the number of patients with activity decreased by 66.4%, after 2 years of therapy - by 72.7%. The mean annual frequency of exacerbations decreased from 1.32 to 0.2 after 12 months, and to 0.086 exacerbations per year after 24 months. The level of disability assessed by the EDSS scale remained virtually unchanged throughout the follow-up. The most common adverse events were haematological abnormalities in the form of lymphopenia and leukopenia. Most patients had mild grade 1-2 lymphopenia on the toxicity scale and recovered to the recommended values (>0.8·109/l) by the beginning of the second course of therapy. No cases of serious adverse events were reported. The results obtained indicate the high efficacy and favorable safety profile of cladribine and are consistent with the data of clinical trials of the drug.

Molecular signature associated with cladribine treatment in patients with multiple sclerosis.

Little is known about the molecular profiling associated with the effect of cladribine in patients with multiple sclerosis (MS). Here, we aimed first to characterize the transcriptomic and proteomic profiles induced by cladribine in blood cells, and second to identify potential treatment response biomarkers to cladribine in patients with MS. Gene, protein and microRNA (miRNA) expression profiles were determined by microarrays (genes, miRNAs) and mass spectrometry (proteins) in peripheral blood mononuclear cells (PBMCs) from MS patients after in vitro treatment with cladribine in its active and inactive forms. Two bioinformatics approaches to integrate the three obtained datasets were applied: (i) a multiomics discriminant analysis (DIABLO - Data Integration Analysis for Biomarker discovery using Latent variable approaches for Omics studies); and (ii) a multi-stage integration of features selected in differential expression analysis on each dataset and then merged. Selected molecules from the in vitro study were quantified by qPCR ex vivo in PBMCs from MS patients receiving cladribine. PBMCs treated in vitro with cladribine were characterized by a major downregulation of gene, protein, and miRNA expression compared with the untreated cells. An intermediate pattern between the cladribine-treated and untreated conditions was observed in PBMCs treated with cladribine in its inactive form. The differential expression analysis of each dataset led to the identification of four genes and their encoded proteins, and twenty-two miRNAs regulating their expression, that were associated with cladribine treatment. Two of these genes (PPIF and NHLRC2), and three miRNAs (miR-21-5p, miR-30b-5p, and miR-30e-5p) were validated ex vivo in MS patients treated with cladribine. By using a combination of omics data and bioinformatics approaches we were able to identify a multiomics molecular profile induced by cladribine in vitro in PBMCs. We also identified a number of biomarkers that were validated ex vivo in PBMCs from patients with MS treated with cladribine that have the potential to become treatment response biomarkers to this drug.

The effect of cladribine on immunoglobulin levels compared to B cell targeting therapies in multiple sclerosis.

Cladribine is a useful therapeutic option in RRMS with moderate to high disease activity. Its oral formulation and tolerability make it a useful alternative to infusion therapies. Cladribine is known to deplete CD19+ B lymphocytes, but its effect on immunoglobulin subsets is unclear. To identify whether cladribine therapy in pwMS reduces immunoglobulin subset levels as a surrogate marker of infection risk. A 'real-world' retrospective analysis of 341 pwMS presenting to a single tertiary centre between March 2017 and July 2021. Differences in immunoglobulin levels between cladribine, other disease-modifying therapies and no active treatment were assessed using a univariate ANOVA. Three hundred and forty-one patients had immunoglobulin levels assessed, with 29 patients treated with cladribine. The mean IgG, IgM and IgA levels on cladribine therapy were 10.44 ± 0.40, 0.99 ± 0.09 and 2.04 ± 0.18 g/L respectively. These were not significantly different from patients not on active treatment. There was a statistically significant reduction in IgG and IgM levels for patients treated with ocrelizumab (9.37 ± 0.19 and 0.68 ± 0.04 g/L) and natalizumab (8.72 ± 0.53 and 0.69 ± 0.12 g/L) compared to patients not on treatment. Cladribine therapy for RRMS was not associated with immunoglobulin subset deficiencies. This is contrasted to ocrelizumab and natalizumab which demonstrate significant reductions in both IgG and IgM levels.

Effect of cladribine on COVID-19 serology responses following two doses of the BNT162b2 mRNA vaccine in patients with multiple sclerosis

Backgroundmultiple sclerosis (MS) patients are treated with immunomodulatory treatments that can influence their ability to develop a protective antibody response to the SARS-CoV-2 vaccine.Vaccine efficacy is important for treatment decision and for patients’ reassurance.The main objective is to assess antibody response to SARS-CoV-2 vaccine in MS patients treated with cladribine.MethodsSerology response was tested in 97 participants, 67 MS patients and 30 healthy controls (HCs), using two independent methods, 2–3 weeks following the second dose of the BNT162b2 vaccine.ResultsHCs (n = 30) and MS patients treated with cladribine (n = 32) had 100% positive serology response against the SARS-CoV-2 spike protein following the second vaccine dose (mean S1/S2-IgG and RBD-IgG:284.5 ± 104.9, 13,041±9411 AU/mL and 226.3 ± 121.4, 10,554±11,405 AU/mL respectively). Comparable findings were observed for untreated MS patients, and interferon beta-1a-treated MS patients (mean S1/S2-IgG: 282.1 ± 100.1, 276.9 ± 94.31 AU/mL respectively). No correlation was found between lymphocyte counts, treatment duration, or time between cladribine dose and vaccination, and serology response or antibody titers.Conclusion and relevanceCladribine treated MS patients are able to produce antibodies to the SARS-CoV-2 mRNA vaccine. In the era of the COVID-19 pandemic, it is reassuring and important for both patients and physicians and will allow to develop consensus guidelines.

Effect of Cladribine on Neuronal Apoptosis: New Insight of In Vitro Study in Multiple Sclerosis Therapy.

Background: Cladribine (2-CdA) can cross the blood–brain barrier, resulting in inhibition of DNA synthesis and repair and disruption of cellular proliferation in actively dividing lymphocytes. No data on effect on neurons are available. Aim: To study “in vitro” 2-CdA apoptotic effects on neurons in healthy donor and multiple sclerosis patient lymphocytes. Methods: Neuroblastoma cells were co-cultured with lymphocytes, with and without 2-CdA. Results: Apoptosis increased in lymphocytes with 2-CdA; increase was also observed when lymphocytes were cultured with neuronal cells. However, neurons were not affected by 2-CdA for apoptosis. Conclusions: 2-CdA causes peripheral and central lymphocyte death preserving neurons, with a reasonable impact on inflammation and neuroprotection.

Cladribine induces long lasting oligoclonal bands disappearance in relapsing multiple sclerosis patients: 10-year observational study

There has been long-term interest in cladribine as a drug for the treatment of MS. The current study focused on the effect of cladribine on oligoclonal bands (OCB) expression in the CSF in relapsing-remitting MS (RRMS) patients observed over 10 years. 29 treatment-naive subjects with RRMS were prospectively enrolled and received induction therapy with subcutaneous parenteral cladribine (at a cumulative dose of 1.8 mg/kg; divided into 6 courses every 5 weeks given for 4-6 days, depending on patients' body weight). Selected patients received maintenance doses in the follow-up period. Isoelectric focusing revealed that 55% of patients did not have OCB in CSF after cladribine treatment as compared to baseline testing when 100% of patients were positive for OCB. There were no significant differences in Expanded Disability Status Scale scores at baseline and at the end of treatment cycle between OCB-positive vs. OCB-negative subgroups. At the last follow-up, OCB-negative patients had lower disability compared to OCB-positive patients (p = 0.03). Cladribine-induced immune reconstitution leads to long lasting suppression of intrathecal humoral response, which might be an additional mechanism that enhances the therapeutic effect on disease progression in RRMS patients.

M2042 Survival in Refractory Coeliac Disease with Aberrant T-Cells After Cladribine Therapy: Evaluation of a Single Center Experience

Background Aims: Approximately 2-5% of adult-onset coeliac disease patients fails to respond to a gluten free diet and develops refractory celiac disease (RCD). Two types of RCD have been recognized: type I with a phenotypically normal and type II with an aberrant intraepithelial Tcell population. In contrast to RCDI, RCDII seems to be unresponsive to common immunosuppressive treatment. Transition into Enteropathy Associated T-cell Lymphoma (EATL) is seen in 50-60%. This study reports on the effect of cladribine (2-CDA), a purine analogue inducing T-cell depletion, regarding clinical, histolopathologic and immunologic parameters. Design and methods: An analysis was performed in a tertiary referral centre for coeliac disease between 2001 and 2008. Overall, 29 patients diagnosed with RCDII (16 men, 13 women) were treated with 2-CDA (0,1mg/kg/day) intravenously for 5 days, in 1-3 courses every 6 months depending on the response. Symptoms of malabsorption, weight, albumin, haemoglobin, Marsh classification and percentage of aberrant intraepithelial T-cells were evaluated during follow-up. Results: At the time of 2-CDA treatment, the mean age of the 29 patients included was 62.6years (SD±7.6). All patients tolerated 2-CDA without serious side effects. The mean follow-up period was 30.6 months (SD±23.6). Sixteen patients (55%) showed a clinical improvement, nineteen (66%) a histopathological improvement, ten (35%) a significant decrease in aberrant T-cells and fourteen (48%) a complete remission (Marsh 0-1) during follow-up. Four patients had a partial small bowel resection due to UJ before 2-CDA treatment, complete remission was seen in three of them. Four non-responders have had bone marrow transplantation (BMT), among them three eventually showed a complete histological remission and one developed an EATL. Sixteen of 29 (55%) RCDII patients presented as ulcerative jejunitis (UJ). Overall, twelve patients (41%) died. Five out of these 12 patients developed an EATL and died within one year after diagnosing EATL. Seven patients died because of progressive refractory state. The 2-, 3-, 4-year survival after 2-CDA therapy was 75%, 62% and 44%, respectively. Conclusion: Although treatment with 2-CDA of patients with RCDII does not prevent EATL development in all RCDII patients, it seems feasible, well tolerated and induces clinical and histological improvement in 50% of the patients, and complete histological remission in 48%. BMT was only an alternative for nonresponders up to 70 years of age.

High Activity and Incomplete Cross Resistance of Nucleoside Analogues Cladribine and Fludarabine Versus Ara-C on Leukemic Cells From Patients With AML

The in vitro activity and cross-resistance pattern of the purine analogues cladribine and fludarabine and the pyrimidine analogue cytarabine on leukemic cells from 170 patients with AML was evaluated using a bioluminescence assay. In in vivo mimicking concentrations, cladribine (50 nmol/L) and fludarabine (2 micromol/L) were more cytotoxic than cytarabine (0.5 micromol/L). The cytotoxic effect of fludarabine correlated weakly to cytarabine (r = 0.37, P < 0.001). The cytotoxic effect of cladribine correlated better to cytarabine (r = 0.49, P = 0.0002) but best to fludarabine (r = 0.82, P < 0.001). There was an absence of correlation between either cladribine or fludarabine and daunorubicin (0.2 micromol/L). Of 45 highly Ara-C-resistant samples, cladribine exerted high or intermediate effect in 54% and fludarabine in 52%. These in vitro data indicate that cladribine and fludarabine are active drugs in the treatment of AML. The cross resistance to cytarabine was not complete, and the drugs can be valuable either as alternatives to Ara-C or in combination therapy for treatment of leukemia resistant to standard therapy.

Influence of 2-chlorodeoxyadenosine (cladribine) on human erythrocytes

2-Chlorodeoxyadenosine (2-CdA, cladribine) is one of the newest chemotherapy drugs which has been around and in use for a few years. Drug in tumour cells causes the inhibition of DNA synthesis and repair processes in replication cells, and the accumulation of DNA strand breaks in nonproliferating cells. The present study was undertaken to characterize the influence of cladribine on the fluidity of the lipid bilayer and protein conformation in human erythrocytes. The effect of cladribine on the erythrocyte membrane structure was examined by electron spin resonance (ESR) spectroscopy and fluorescence measurements. It was observed that under the studied conditions (c: 0.1-5 microg/ml, t = 1 h, 37 degrees C), cladribine localised mainly in the erythrocyte membrane and affected its organization. The alterations in the fluidity were observed mainly in the deeper regions of the cell membrane. The incorporation of drug into human erythrocytes also caused negligible conformational alterations of membrane cytoskeletal proteins and did not change the internal viscosity of the cells. We can conclude from these data that 2-CdA in vitro is significantly much less toxic to erythrocytes than anthracycline drugs, which are used in treatment of leukemias. However, the higher concentrations of 2-CdA (about 5 microg/ml) can be also toxic to erythrocytes.

Determination of the in vivo effects of cladribine alone and its combination with cyclophosphamide or cyclophosphamide and mitoxantrone on Bax and Bcl-2 protein expression in B-CLL cells

The present study investigated a correlation between expression of Bcl-2 family members, Bax and Bcl-2 (the Bax/Bcl-2 ratio values) in B-CLL cells in vivo and the response of these cells to chemotherapy. Western blot technique combined with videodensitometry was used for Bax and Bcl-2 determination in homogenate, nuclear and postnuclear fractions of mononuclear cells isolated from peripheral blood of B-CLL patients treated with cladribine alone (C), and in combination with cyclophosphamide (CC) or mitoxantrone and cyclophosphamide (CMC). The Bax/Bcl-2 ratio values were changed in B-CLL cells originated from blood samples of patients treated by the three therapy protocols, and was the most elevated in the case of CMC treatment. High degree of B-CLL cell apoptosis induction with cladribine combined with mitoxantrone and cyclophosphamide was confirmed by DNA fragmentation and an appearance of apoptotic morphology among leukemic cells from the blood of patients treated with this form of combined therapy.

The effects of cladribine and fludarabine on DNA methylation in K562 cells

The effects of the antileukemic adenosine analogues, 2-chloro-2'-deoxyadenosine (cladribine) and 9-beta-D-arabinosyl-2-fluoroadenine (fludarabine), on DNA methylation were studied in a cell line K562. It was previously found that both drugs inactivated SAH hydrolase, an enzyme which participates in the "active methyl" cycle. The study examined the effects of these drugs on three aspects of DNA methylation: (i) activity of endogenous C-5 DNA methyltransferase; (ii) capacity of genomic DNA (gDNA) to accept methyl groups, transferred from S-adenosylmethionine by the bacterial methyltransferase, SssI; (iii) estimation of changes of methylated cytosine levels in gDNA, using methylation-dependent restriction analysis. Cladribine and fludarabine inhibited C-5 DNA methyltransferase, with ED(50) values of 3.5 and 47.0 microM, respectively, after 24hr cell growth in the presence of the drugs. After 48 hr growth of cells with cladribine (0.1 microM) or fludarabine (3 microM), the capacity of DNA to accept methyl groups, in the presence of exogenous bacterial SssI methylase, increased by approximately 1.8 and 1.6 times, respectively, compared to control DNA. Digestion of gDNA with endonucleases HpaII and BssHII followed by SssI DNA methylation, indicated that cladribine (0.1 microM) reduced the level of methylated cytosines in both CpG islands and CCGG sequences, sensitive to HpaII restriction enzyme. Inhibition of DNA methylation by fludarabine was observed mainly in CpG dinucleotide located within sequences sensitive to HpaII. The perturbation of DNA methylation was considered as a complex process. Our findings for cladribine and fludarabine should be regarded as an extra element of their antileukemic efficacy.

Effect of Cladribine, fludarabine, and 5-aza-deoxycytidine on S-adenosylmethionine (SAM) and nucleotides pools in stimulated human lymphocytes.

Cladribine (2-chloro-2′-deoxyadenosine, 2CdA) and Fludarabine (9-β-D-arabino-syl-2-fluoro-adenine) are 2-halogenated adenosine analogues which have found clinical application for the treatment of lymphocytic and lymphoid leukemias.1 Cladribine and Fludarabine result in apoptosis of cells2 and it has been established that the mechanisms of action of both drugs lead via their phosphorylated derivates to inhibition of DNA synthesis. Recently, we have reported the block of deoxyadenosine (dAdo) metabolism by Cladribine in lysates of CNS lymphoma cells3 and in lysates of human normal lymphocytes.4 A complete inhibition of phosphorylation of dAdo, and 60% of inhibition of adenosine deaminase (ADA) activity were observed in in vitro studies.KeywordsChronic Lymphocytic LeukemiaAdenosine DeaminaseLymphoid LeukemiaNucleotide PoolHeptanesulfonic AcidThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Effects of Cladribine, Fludarabine and 5-aza-deoxycytidine on s-adenosylmethionine (SAM) and nucleotides pools in stimulated human lymphocytes

Effects of Cladribine, Fludarabine and 5-aza-deoxycytidine on s-adenosylmethionine (SAM) and nucleotides pools in stimulated human lymphocytes