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Clinical Pharmacology in Drug... Feb 2018Anagrelide is an established therapy for essential thrombocythemia. Common adverse effects have been linked to peak plasma concentrations of anagrelide and its 3OH... (Randomized Controlled Trial)
Randomized Controlled Trial
Anagrelide is an established therapy for essential thrombocythemia. Common adverse effects have been linked to peak plasma concentrations of anagrelide and its 3OH metabolite. Our study was performed to investigate the pharmacokinetics (PK) of a novel anagrelide extended-release (AER) formulation and its active metabolites. Thirty healthy volunteers were randomized to receive either 2 mg AER (under fasting and fed conditions) or 2 mg commercially available reference product (CARP) in an open-label, 3-way crossover trial with washout periods of 6 days. Plasma concentrations of anagrelide and its active metabolites were assessed by tandem mass spectrometry. The PK differed significantly between all treatment periods. Bioavailability of AER was 55% of the CARP under fasting conditions and 60% under fed conditions. C , AUCt, and AUC∞ were significantly higher and T and T were significantly shorter after the CARP compared with AER. Food had a significant impact on the PK of AER, increasing the C and AUC while reducing the T , plateau, and mean residence time. Both formulations were well tolerated, with a trend toward more frequently occurring adverse events after the CARP. The PK of AER and the CARP differed significantly in all parameters. Food enhanced the bioavailability of AER.
Topics: Administration, Oral; Adolescent; Adult; Cross-Over Studies; Delayed-Action Preparations; Fasting; Female; Fibrinolytic Agents; Food-Drug Interactions; Healthy Volunteers; Humans; Male; Middle Aged; Platelet Aggregation Inhibitors; Quinazolines; Young Adult
PubMed: 28301098
DOI: 10.1002/cpdd.340 -
Frontiers in Genetics 2022Glioma is the most malignant cancer of the central nervous system. There are various therapies for treating gliomas, but their outcomes are not satisfactory. Therefore,...
Glioma is the most malignant cancer of the central nervous system. There are various therapies for treating gliomas, but their outcomes are not satisfactory. Therefore, new targets for glioma treatment are needed. This study examined the cadherin-6 (CDH6) expression in gliomas using The Cancer Genome Atlas and Chinese Glioma Genome Atlas datasets. CDH6 expression positively correlated with the World Health Organization (WHO) tumor grade and negatively correlated with patient prognosis. A significant decrease in CDH6 promoter methylation was identified with an increase in the WHO grade severity. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses suggested that CDH6 might be involved in cell-cell interactions and immune processes in the glioma microenvironment. Weighted gene co-expression network analysis revealed a correlation between CDH6 and cell adhesion molecules, focal adhesions, phosphatidylinositol 3-kinase-protein kinase B signaling pathways, nuclear division, chromosome segregation, mitotic nuclear division, and immune-related pathways. CDH6 strongly correlated with immunosuppressive cells, including regulatory T cells, monocytes, macrophages, tumor-associated macrophages, and myeloid-derived suppressor cells. It also showed correlations with immune-active cells such as B cells, CD8 T cells, and dendritic cells. Single-cell analysis showed that CDH6 was expressed mainly in astrocyte (AC)-like malignant cells. Differentially expressed genes of AC-like malignant cells were found to be associated with stress response, membranous processes, viral infections, and several types of cancers. Potential drugs associated with high CDH6 expression were also predicted, including AMG-22, rutin, CCT128930, deforolimus, bis(maltolato)oxovanadium, anagrelide, vemurafenib, CHIR-98014, and AZD5582. Thus, this study showed that CDH6 correlates with glioma immune infiltration, it is expressed mainly in AC-like malignant cells, and it may act as a new target for glioma therapy.
PubMed: 35938030
DOI: 10.3389/fgene.2022.949552 -
Clinical Medicine (London, England) 2005
Review
Topics: Antineoplastic Agents; Benzamides; Fibrinolytic Agents; Hematocrit; Humans; Hydroxyurea; Imatinib Mesylate; Myeloproliferative Disorders; Phlebotomy; Piperazines; Pyrimidines; Quinazolines; Thrombosis
PubMed: 16138485
DOI: 10.7861/clinmedicine.5-4-328 -
Cardiovascular Toxicology Mar 2021Essential thrombocythaemia (ET) is a rare myeloproliferative neoplasm. This multicentre, Phase 3b, randomised, open-label, non-inferiority study investigated the cardiac... (Comparative Study)
Comparative Study
Essential thrombocythaemia (ET) is a rare myeloproliferative neoplasm. This multicentre, Phase 3b, randomised, open-label, non-inferiority study investigated the cardiac safety, efficacy and tolerability of first-line treatment with anagrelide or hydroxyurea in high-risk ET patients for up to 3 years. Eligible patients aged ≥ 18 years with a diagnosis of high-risk ET confirmed by bone marrow biopsy within 6 months of randomisation received anagrelide (n = 75) or hydroxyurea (n = 74), administered twice daily. Treatment dose for either compound was titrated to the lowest dose needed to achieve a response. Planned primary outcome measures were change in left ventricular ejection fraction from baseline over time and platelet count at Month 6. Planned secondary outcome measures were platelet count change from baseline at Months 3 and 36; percentage of patients with complete or partial response; time to complete or partial response; number of patients with thrombohaemorrhagic events; and changes in white blood cell count or red blood cell count over time. Neither treatment altered cardiac function. There were no significant differences in adverse events between treatment groups, and no reports of malignant transformation. The incidence of disease-related thrombotic or haemorrhagic events was numerically higher in anagrelide-treated patients. Both treatments controlled platelet counts at 6 months, with the majority of patients experiencing complete or partial responses. In conclusion, these results suggest that long-term treatment with anagrelide is not associated with adverse effects on cardiac function. This is one of the few studies using left ventricular ejection fraction assessment and central biopsy reading to confirm the diagnosis of ET.Trial registration number: Clinicaltrials.gov NCT00202644.
Topics: Adolescent; Adult; Aged; Biopsy; Blood Platelets; Bone Marrow Examination; Echocardiography; Europe; Female; Humans; Hydroxyurea; Male; Middle Aged; Platelet Count; Quinazolines; Stroke Volume; Thrombocythemia, Essential; Time Factors; Treatment Outcome; Ventricular Dysfunction, Left; Ventricular Function, Left; Young Adult
PubMed: 33123978
DOI: 10.1007/s12012-020-09615-0 -
Journal of Thrombosis and Haemostasis :... Apr 2015Anagrelide represents a treatment option for essential thrombocythemia patients. It lowers platelet counts through inhibition of megakaryocyte maturation and...
BACKGROUND AND OBJECTIVES
Anagrelide represents a treatment option for essential thrombocythemia patients. It lowers platelet counts through inhibition of megakaryocyte maturation and polyploidization, although the basis for this effect remains unclear. Based on its rapid onset of action, we assessed whether, besides blocking megakaryopoiesis, anagrelide represses proplatelet formation (PPF) and aimed to clarify the underlying mechanisms.
METHODS AND RESULTS
Exposure of cord blood-derived megakaryocytes to anagrelide during late stages of culture led to a dose- and time-dependent inhibition of PPF and reduced proplatelet complexity, which were independent of the anagrelide-induced effect on megakaryocyte maturation. Whereas anagrelide was shown to phosphorylate cAMP-substrate VASP, two pharmacologic inhibitors of the cAMP pathway were completely unable to revert anagrelide-induced repression in megakaryopoiesis and PPF, suggesting these effects are unrelated to its ability to inhibit phosphodiesterase (PDE) 3. The reduction in thrombopoiesis was not the result of down-regulation of transcription factors which coordinate PPF, while the myosin pathway was identified as a candidate target, as anagrelide was shown to phosphorylate the myosin light chain and the PPF phenotype was partially rescued after inhibition of myosin activity with blebbistatin.
CONCLUSIONS
The platelet-lowering effect of anagrelide results from impaired megakaryocyte maturation and reduced PPF, both of which are deregulated in essential thrombocythemia. These effects seem unrelated to PDE3 inhibition, which is responsible for anagrelide's cardiovascular side-effects and antiplatelet activity. Further work in this field may lead to the potential development of drugs to treat thrombocytosis in myeloproliferative disorders with an improved pharmacologic profile.
Topics: Blood Platelets; Case-Control Studies; Cell Adhesion Molecules; Cells, Cultured; Cyclic AMP; Dose-Response Relationship, Drug; Fetal Blood; Hematopoietic Stem Cells; Heterocyclic Compounds, 4 or More Rings; Humans; Megakaryocytes; Microfilament Proteins; Myosins; Phosphodiesterase 3 Inhibitors; Phosphoproteins; Phosphorylation; Platelet Aggregation Inhibitors; Quinazolines; Signal Transduction; Thrombocythemia, Essential; Thrombopoiesis; Time Factors; Transcription Factors
PubMed: 25604267
DOI: 10.1111/jth.12850 -
Oncology (Williston Park, N.Y.) Aug 2001Myeloproliferative disorders originate in the clonal expansion of a transformed pluripotential hematopoietic progenitor cell. This results in a group of syndromes that... (Review)
Review
Myeloproliferative disorders originate in the clonal expansion of a transformed pluripotential hematopoietic progenitor cell. This results in a group of syndromes that include polycythemia vera, essential thrombocythemia, chronic myelocytic leukemia, and agnogenic myeloid metaplasia. Diagnostic criteria forpolycythemia vera and essential thrombocythemia were codified by the Polycythemia Vera Study Group in 1967 and 1977. Subsequent modifications include criteria for evidence of clonal proliferation by abnormal bone marrow karyotype and demonstration of erythropoietin-independence of erythropoiesis or reduced serum erythropoietin. Phlebotomy is the mainstay of treatment for polycythemia vera. The defining characteristic of essential thrombocythemia is a sustained elevation of the platelet count above 600,000/microL in an untreated patient. Symptoms and risk factors are the main determinants of treatment options for patients with essential thrombocythemia. High-risk patients are candidates for cytoreduction, whereas lower-risk patients receive either no treatment, low-dose aspirin, or another antithrombotic therapy. The availability of newer nonleukemogenic and megakaryocyte-specific agents warrants a reassessment of current treatment options.
Topics: Enzyme Inhibitors; Humans; Hydroxyurea; Immunologic Factors; Interferon-alpha; Polycythemia Vera; Quinazolines; Thrombocytosis
PubMed: 11548978
DOI: No ID Found -
Blood Apr 1992Anagrelide is a new therapeutic compound recently demonstrated to have a rapid and selective thrombocytopenic effect in humans. The effects of anagrelide were evaluated...
Anagrelide is a new therapeutic compound recently demonstrated to have a rapid and selective thrombocytopenic effect in humans. The effects of anagrelide were evaluated in plasma clot and liquid suspension cultures of optimally stimulated normal human peripheral blood megakaryocyte progenitors in order to determine the mechanism of its thrombocytopenic activity. In plasma clot cultures, at clinically relevant, therapeutic concentrations (5 to 50 ng/mL), anagrelide exerted no significant inhibitory effect on megakaryocyte colony numbers or colony size. Only at anagrelide concentrations of 10 to 500 times therapeutic doses did anagrelide inhibit megakaryocyte colony development: an anagrelide concentration of 5 micrograms/mL reduced colony numbers by 57% and colony size by 31%. In contrast, lower, therapeutic anagrelide concentrations exerted profound effects in liquid culture on megakaryocyte cytoplasmic maturation, size, and DNA content. When present for the entire 12-day culture duration, anagrelide induced left-shifted megakaryocyte maturation and reduced both megakaryocyte ploidy and megakaryocyte diameter. Anagrelide, at concentrations of 5 to 50 ng/mL, shifted the modal cultured megakaryocyte morphologic stage from III to II, reduced the model ploidy value from 16N to 8N, and decreased the mean megakaryocyte diameter by up to 22%, from 27.6 microns to 21.6 microns. Megakaryocyte diameter was significantly reduced in most instances, even when analyzed as a function of morphologic stage. When anagrelide was added to the cultures after 6- and 9-day delays (during the final 6 and 3 days, respectively, of culture), similar inhibitory effects on megakaryocyte maturation stage and ploidy distribution were observed. However, the magnitude of the left-shift in ploidy appeared to be less as the duration of anagrelide exposure was reduced. Conversely, megakaryocyte diameter was not significantly affected by the shorter 3- and 6-day anagrelide exposures. These data indicate that therapeutic concentrations of anagrelide influence primarily the postmitotic phase of megakaryocyte development, decreasing platelet production by reducing megakaryocyte size and ploidy, as well as by disrupting full megakaryocyte maturation. Inhibition of megakaryocyte diameter appears to require more prolonged anagrelide exposure than inhibition of maturation stage and ploidy. The molecular mechanisms responsible for the inhibitory effects of anagrelide on megakaryocytopoiesis remain to be defined.
Topics: Cell Aggregation; Cells, Cultured; Dose-Response Relationship, Drug; Humans; Kinetics; Megakaryocytes; Platelet Aggregation Inhibitors; Ploidies; Quinazolines; Thrombocytopenia; Time Factors
PubMed: 1562721
DOI: No ID Found -
Turkish Journal of Haematology :... Dec 2021
Topics: Humans; Leg Ulcer; Quinazolines
PubMed: 34445859
DOI: 10.4274/tjh.galenos.2021.2021.0399 -
Case Reports in Hematology 2023VEXAS syndrome stands for vacuoles, E1 enzyme, -linked, autoinflammatory, somatic syndrome. The syndrome is a combined hematological and rheumatological condition caused...
VEXAS syndrome stands for vacuoles, E1 enzyme, -linked, autoinflammatory, somatic syndrome. The syndrome is a combined hematological and rheumatological condition caused by a somatic mutation in the . There is an association between VEXAS and hematological conditions such as myelodysplastic syndrome (MDS), monoclonal gammopathies of uncertain conditions (MGUS), multiple myeloma (MM), and monoclonal B-cell lymphoproliferative conditions. There are not many descriptions of patients having VEXAS in combination with myeloproliferative neoplasm (MPN). With this article, we want to present a case history of a man in his sixties with a V617F mutated essential thrombocythemia (ET) developing VEXAS syndrome. The inflammatory symptoms occurred three and a half years after the ET diagnosis. He started to experience symptoms of autoinflammation and an overall worsening of his health, and blood work showed high inflammatory markers, leading to repeated hospitalizations. His major complaint was stiffness and pain, and high dosages of prednisolone were necessary to obtain pain relief. He subsequently developed anemia and significantly variable levels of thrombocytes, which previously were at a steady level. To evaluate his ET, we made a bone marrow smear demonstrating vacuolated myeloid and erythroid cells. Having VEXAS syndrome in mind, genetic testing identifying the gene mutation was performed, thus confirming our suspicion. The work-up with myeloid panel on his bone marrow identified genetic mutation in the too. After developing VEXAS syndrome, he experienced thromboembolic events with both cerebral infarction and pulmonary embolism. Thromboembolic events are also common in mutated patients, but in his case, they presented first after VEXAS had developed. Throughout the course of his condition, several attempts with prednisolone tapering and steroid sparing drugs were tried. He could not get pain relief unless the combination of medications included a relatively high dose of prednisolone. Currently, the patient uses prednisolone, anagrelide, and ruxolitinib, with partial remission and fewer hospitalizations and more stabilized hemoglobin and thrombocytes.
PubMed: 36879894
DOI: 10.1155/2023/6551544 -
Clinical and Applied... Oct 1999Low-risk essential thrombocythemia patients include patients aged 18 to < 80 years with no vascular risk factor or previous thrombosis, no associated disease, a normal... (Review)
Review
Low-risk essential thrombocythemia patients include patients aged 18 to < 80 years with no vascular risk factor or previous thrombosis, no associated disease, a normal life expectancy, and a platelet count between 400 and 1,000 x 10(9)/L up to 1,500 x 10(9)/L. Asymptomatic essential thrombocythemia patients may be at risk for microvascular circulation disturbances. The indication for low-dose aspirin in asymptomatic essential thrombocythemia patients is uncertain, therefore randomization for aspirin 50 mg versus placebo is recommended. Symptomatic essential thrombocythemia patients with erythromelalgia and its ischemic complications, atypical transient ischemic attacks, minor stroke, visual disturbances and "superficial thrombophlebitis" in the absence of bleeding, vascular risk factors, or vascular disease have a clear indication for aspirin in a regular dose. To determine whether 50 mg/day is as effective as 100 mg/day for the prophylaxis of microvascular circulation disturbances in essential thrombocythemia, a randomized trial comparing low-dose aspirin 50 mg versus 100 mg at platelet counts between 400 and 1,000 up to 1,500 x 10(9)/L is recommended. To address the question whether reduction of the platelet count to normal (< 350 x 10(9)/L) is as effective as low-dose aspirin for the long-term relief of microvascular circulation disturbances, a randomized study comparing low-dose aspirin with the correction of platelet count to normal by anagrelide is recommended. High-risk essential thrombocythemia patients have a clear indication for platelet reductive therapy, including: (a) platelets > 1,500 x 10(9)/L, history of major thrombosis (myocardial infarction, stroke, peripheral occlusive vascular disease), or presence of vascular disease (e.g., arteriosclerosis); (b) history or presence of spontaneous or major bleedings, bleedings elicited by low-dose aspirin for the secondary prevention of vascular complications in essential thrombocythemia at platelet counts < 1500 x 10(9)/L, and side effects of long-term aspirin treatment such as gastritis; and progression from low- to high-risk essential thrombocythemia patients during follow-up or progressive myeloproliferative disease such as significant splenomegaly, myelofibrosis, leukocytosis, etc. To address the question of optimal treatment of high-risk essential thrombocythemia patients, randomization for anagrelide versus interferon at < 65 years of age and anagrelide versus hydroxyurea at an age > 65 years is recommended.
Topics: Adolescent; Adult; Aged; Aspirin; Humans; Middle Aged; Platelet Aggregation Inhibitors; Platelet Count; Randomized Controlled Trials as Topic; Thrombocytosis; Vascular Diseases
PubMed: 10726022
DOI: 10.1177/107602969900500408