An antiplatelet drug (antiaggregant), also known as a platelet agglutination inhibitor or platelet aggregation inhibitor, is a member of a class of pharmaceuticals that decrease platelet aggregation and inhibit thrombus formation. They are effective in the arterial circulation where classical Vitamin K antagonist anticoagulants have minimal effect.
In oncology, polycythemia vera (PV) is an uncommon myeloproliferative neoplasm in which the bone marrow makes too many red blood cells. The majority of cases are caused by mutations in the JAK2 gene, most commonly resulting in a single amino acid change in its protein product from valine to phenylalanine at position 617.
In hematology, thrombocytopenia is a condition characterized by abnormally low levels of platelets in the blood. Low levels of platelets in turn may lead to prolonged or excessive bleeding. It is the most common coagulation disorder among intensive care patients and is seen in a fifth of medical patients and a third of surgical patients.
A megakaryocyte is a large bone marrow cell with a lobated nucleus that produces blood platelets (thrombocytes), which are necessary for normal clotting. In humans, megakaryocytes usually account for 1 out of 10,000 bone marrow cells, but can increase in number nearly 10-fold during the course of certain diseases. Owing to variations in combining forms and spelling, synonyms include megalokaryocyte and megacaryocyte.
Chronic myelogenous leukemia (CML), also known as chronic myeloid leukemia, is a cancer of the white blood cells. It is a form of leukemia characterized by the increased and unregulated growth of myeloid cells in the bone marrow and the accumulation of these cells in the blood. CML is a clonal bone marrow stem cell disorder in which a proliferation of mature granulocytes and their precursors is found; characteristic increase in basophils is clinically relevant. It is a type of myeloproliferative neoplasm associated with a characteristic chromosomal translocation called the Philadelphia chromosome.
Imatinib, sold under the brand names Gleevec and Glivec (both marketed worldwide by Novartis) among others, is an oral targeted therapy medication used to treat cancer. Imatinib is a small molecule inhibitor targeting multiple tyrosine kinases such as CSF1R, ABL, c-KIT, FLT3, and PDGFR-β. Specifically, it is used for chronic myelogenous leukemia (CML) and acute lymphocytic leukemia (ALL) that are Philadelphia chromosome–positive (Ph+), certain types of gastrointestinal stromal tumors (GIST), hypereosinophilic syndrome (HES), chronic eosinophilic leukemia (CEL), systemic mastocytosis, and myelodysplastic syndrome.
In hematology, thrombocythemia is a condition of high platelet (thrombocyte) count in the blood. Normal count is in the range of 150×109 to 450×109 platelets per liter of blood, but investigation is typically only considered if the upper limit exceeds 750×109/L.
Hydroxycarbamide, also known as hydroxyurea, is a medication used in sickle-cell disease, essential thrombocythemia, chronic myelogenous leukemia, polycythemia vera, and cervical cancer. In sickle-cell disease it increases fetal hemoglobin and decreases the number of attacks. It is taken by mouth.
In hematology, essential thrombocythemia (ET) is a rare chronic blood cancer characterised by the overproduction of platelets (thrombocytes) by megakaryocytes in the bone marrow. It may, albeit rarely, develop into acute myeloid leukemia or myelofibrosis. It is one of the blood cancers wherein the bone marrow produces too many white or red blood cells, or platelets.
Dipyridamole is a nucleoside transport inhibitor and a PDE3 inhibitor medication that inhibits blood clot formation when given chronically and causes blood vessel dilation when given at high doses over a short time.
Primary myelofibrosis (PMF) is a rare bone marrow blood cancer. It is classified by the World Health Organization (WHO) as a type of myeloproliferative neoplasm, a group of cancers in which there is activation and growth of mutated cells in the bone marrow. This is most often associated with a somatic mutation in the JAK2, CALR, or MPL genes. In PMF, the bony aspects of bone marrow are remodeled in a process called osteosclerosis; in addition, fibroblast secrete collagen and reticulin proteins that are collectively referred to as (fibrosis). These two pathological processes compromise the normal function of bone marrow resulting in decreased production of blood cells such as erythrocytes, granulocytes and megakaryocytes, the latter cells responsible for the production of platelets.
Myeloproliferative neoplasms (MPNs) are a group of rare blood cancers in which excess red blood cells, white blood cells or platelets are produced in the bone marrow. Myelo refers to the bone marrow, proliferative describes the rapid growth of blood cells and neoplasm describes that growth as abnormal and uncontrolled.
Cyclic guanosine monophosphate-specific phosphodiesterase type 5 is an enzyme from the phosphodiesterase class. It is found in various tissues, most prominently the corpus cavernosum and the retina. It has also been recently discovered to play a vital role in the cardiovascular system.
Myelophthisic anemia is a severe type of anemia found in some people with diseases that affect the bone marrow. Myelophthisis refers to the displacement of hemopoietic bone-marrow tissue by fibrosis, tumors, or granulomas. The word comes from the roots myelo-, which refers to bone marrow, and phthysis, shrinkage or atrophy.
The Prostacyclin receptor, also termed the prostaglandin I2 receptor or just IP, is a receptor belonging to the prostaglandin (PG) group of receptors. IP binds to and mediates the biological actions of prostacyclin (also termed Prostaglandin I2, PGI2, or when used as a drug, epoprostenol). IP is encoded in humans by the PTGIR gene. While possessing many functions as defined in animal model studies, the major clinical relevancy of IP is as a powerful vasodilator: stimulators of IP are used to treat severe and even life-threatening diseases involving pathological vasoconstriction.
Acute megakaryoblastic leukemia (AMKL) is life-threatening leukemia in which malignant megakaryoblasts proliferate abnormally and injure various tissues. Megakaryoblasts are the most immature precursor cells in a platelet-forming lineage; they mature to promegakaryocytes and, ultimately, megakaryocytes which cells shed membrane-enclosed particles, i.e. platelets, into the circulation. Platelets are critical for the normal clotting of blood. While malignant megakaryoblasts usually are the predominant proliferating and tissue-damaging cells, their similarly malignant descendants, promegakaryocytes and megakaryocytes, are variable contributors to the malignancy.
Acute panmyelosis with myelofibrosis (APMF) is a poorly defined disorder that arises as either a clonal disorder, or following toxic exposure to the bone marrow.
Ruxolitinib, sold under the brand name Jakafi among others, is a medication used for the treatment of intermediate or high-risk myelofibrosis, a type of myeloproliferative neoplasm that affects the bone marrow; polycythemia vera, when there has been an inadequate response to or intolerance of hydroxyurea; and steroid-refractory acute graft-versus-host disease. Ruxolitinib is a Janus kinase inhibitor. It was developed and marketed by Incyte Corp in the US under the brand name Jakafi, and by Novartis elsewhere in the world, under the brand name Jakavi.
Fedratinib, sold under the brand name Inrebic, is an anti-cancer medication used to treat myeloproliferative diseases including myelofibrosis. It is used in the form of fedratinib hydrochloride capsules that are taken by mouth. It is a semi-selective inhibitor of Janus kinase 2 (JAK-2). It was approved by the FDA on 16 August 2019.
Prefibrotic primary myelofibrosis (Pre-PMF) is a rare blood cancer, classified by the World Health Organization as a distinct type of myeloproliferative neoplasm in 2016. The disease is progressive to overt primary myelofibrosis, though the rate of progression is variable and not all patients progress. Symptoms and presentation can mimic essential thrombocythemia, with the main differentiator for pre-PMF being the presence of fibrosis in the bone marrow.
