bl-4162a and Cardiovascular-Diseases

Anagrelide (ANA) is a drug with specific platelet-lowering activity, used primarily in ET, registered as a second-line drug in essential thrombocythemia (ET) in Europe and in some countries as first-line therapy, in USA licensed by FDA for thrombocythemia in myeloproliferative neoplasms (MPN). The platelet-lowering efficacy is similar to that of hydroxycarbamide (HC), around 70 % complete response and 90 % partial response. Side effects are common, especially headache and tachycardia, but usually subside or disappear within a few weeks. Around 20 % of patients stop ANA therapy due to side effects or insufficient response. Studies of treatment patterns in Europe show that ANA is preferentially given to younger patients, probably because of the concern for a possible leukemogenic effect of the common first-line drug, HC. Only two randomized studies have compared the efficacy of ANA and HC in preventing thrombosis and haemorrhage, the larger of them showing a slightly better efficacy of HC, the other showing non-inferiority of ANA to HC. A recent observational 5-year study of 3600 patients shows a low and basically similar efficacy of ANA and other cytoreductive therapies in ET. ANA does not appear to inhibit fibrosis development, and probably due to its anticoagulation properties, the combination of ASA and ANA produces an increased rate of haemorrhage. Combination of ANA with HC or interferon (IFN) is feasible and effective in patients with insufficient platelet response to mono-therapy.

Topics: Age Factors; Bone Marrow; Cardiovascular Diseases; Humans; Interferon-alpha; Myeloproliferative Disorders; Platelet Aggregation Inhibitors; Quinazolines; Tachycardia; Thrombocythemia, Essential

The clinical course of the classic myeloproliferative neoplasms (MPNs) is burdened by an increased rate of cardiovascular events, which are the major cause of mortality. Age and history of thrombosis are the criteria used to stratify patients to the most appropriate therapeutic options. However, the mechanisms ultimately responsible for the increased thrombotic tendency have not yet been elucidated; abnormalities of blood cell count, neutrophil and platelet activation, and a state of hypercoagulability can all occur. Recurrent mutations in JAK2 or MPL have been described in MPNs and serve as disease markers. There is also evidence that a JAK2V617F mutant state represents an independent factor associated with thrombosis, and abnormalities of cell function attributable to JAK2V617F have been characterized. It is hoped that elucidation of the role mutant JAK2 plays in MPNs will improve our understanding of the pathophysiology of thrombosis and eventually result in improved patient treatment using molecularly targeted drugs.

Topics: Amino Acid Substitution; Aspirin; Cardiovascular Diseases; Clinical Trials as Topic; Fibrinolytic Agents; Humans; Incidence; Interferon-alpha; Janus Kinase 2; Multicenter Studies as Topic; Mutation, Missense; Myeloproliferative Disorders; Phenotype; Point Mutation; Quinazolines; Thrombophilia; Thrombosis

Topics: Acute Disease; Alkylating Agents; Aspirin; Cardiovascular Diseases; Clone Cells; Gene Expression; Hemorrhage; Humans; Hydroxyurea; Leukemia, Myeloid; Megakaryocytes; Platelet Aggregation Inhibitors; Quinazolines; Risk; Thrombocythemia, Essential; Thrombophilia

Anagrelide is an oral imidazoquinazoline agent with an anti-cyclic AMP phosphodiesterase activity and inhibits platelet aggregation in both humans and animals. In addition, it has in humans a species-specific platelet-lowering activity observed at dose levels lower than those required to inhibit platelet aggregation. Because of this, the drug has been tested in patients with clonal thrombocytosis and has been shown to have potent platelet-reducing activity in essential thrombocythemia (ET) and related disorders. The mechanism of action may involve the drug's interference with megakaryocyte maturation. More than 90% of patients with ET respond to anagrelide regardless of the presence or absence of previous therapy. The responses are durable with a median maintenance dose of approximately 2 to 2.5 mg/day. Side effects are related mostly to the drug's direct vasodilating and positive inotropic effects and include headache, fluid retention, tachycardia, and arryhthmias. The place of anagrelide therapy in the current management of patients with ET is discussed.

Topics: Animals; Bone Marrow; Cardiovascular Diseases; Clinical Trials as Topic; Cohort Studies; Hematopoiesis; Hemodynamics; Humans; Megakaryocytes; Middle Aged; Myeloproliferative Disorders; Platelet Aggregation Inhibitors; Quinazolines; Thrombocythemia, Essential; Thrombosis

In this prospective observational single-center study, 55 patients with essential thrombocythemia who were candidates for second line treatment with anagrelide (ANA) received a preliminary cardiovascular (CV) clinical, instrumental and biochemical evaluation (CV history and symptoms, CV risk factors, blood pressure, heart rate, ECG and ECHO-cardio parameters, Troponin I, NT-proBNP). After this in-depth CV screening, 54 out of 55 patients were deemed to be fit for ANA treatment. Thirty-eight of the 55 patients received ANA treatment for a median of 36 months (range 3-48), and were monitored using the same CV evaluation. Fourteen of these 38 patients manifested CV adverse events (10 palpitation, 4 edema, 2 arterial hypertension, 2 acute myocardial infarction) that were not predicted by the in-depth CV evaluation, and that led to ANA withdrawal in only one case (non-cardiac refractory edema). In conclusion, the planned in-depth CV evaluation did not appear to be necessary in ET patients to evaluate their suitability for ANA treatment, and, moreover, was not able to predict the occurrence of CV adverse events during ANA treatment. Nevertheless, the CV adverse events (mostly palpitations and edema) were easily managed by the hematologists, and required the cardiologist involvement in very few selected cases.

Topics: Adult; Aged; Cardiovascular Diseases; Electrocardiography; Female; Follow-Up Studies; Humans; Male; Middle Aged; Monitoring, Physiologic; Natriuretic Peptide, Brain; Peptide Fragments; Platelet Aggregation Inhibitors; Prospective Studies; Quinazolines; Thrombocythemia, Essential; Troponin I

This retrospective study of the thrombocythemia Italian registry (RIT) documented that 71 (30.6%) out of 232 ET patients experienced 88 cardiovascular adverse events (CV-AEs) during anagrelide treatment (522 pt-y). The rate of CV-AEs was: 24.1% for palpitations, 4.3% for angina, 3.5% for arterial hypertension, 3.0% for congestive heart failure, 1.8% for arrhythmia, 0.9% for AMI, 0.4% for pericardial effusion. CV-AEs led to treatment discontinuation in nine (3.9%) patients, while in the remaining cases they were managed by pharmacological intervention and/or patient life style improvement. CV-AEs had no relationship with patient characteristics (including older age). A significant relationship was found only with a higher anagrelide induction dose. In the absence of any agreed protocol, a cardiovascular instrumental evaluation (CV-IE) was performed in 102 (44%) patients before commencement of anagrelide (with higher rate after the anagrelide/Xagrid EMA approval of 2004), and in 84 (36%) patients during treatment. Patients with and without CV-IEs, who resulted completely balanced for all their characteristics, did not significantly differ in the occurrence of CV-AEs. In conclusion, this study on ET patients treated with anagrelide shows that CV-AEs, equally distributed in younger and older subjects, were mostly mild and easily manageable, allowing safe treatment continuation in the majority of cases. Moreover, routinely performing a CV-IE did not appear to anticipate the occurrence of CV-AEs.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Cardiovascular Diseases; Child; Cohort Studies; Drug-Related Side Effects and Adverse Reactions; Female; Follow-Up Studies; Humans; Male; Middle Aged; Platelet Aggregation Inhibitors; Quinazolines; Retrospective Studies; Thrombocythemia, Essential; Withholding Treatment; Young Adult

Topics: Cardiovascular Diseases; Female; Humans; Male; Quinazolines; Thrombocythemia, Essential; Withholding Treatment