From the Guidelines
Anagrelide is not recommended for patients with severe leukocytosis due to its inability to effectively reduce white blood cell counts and potential to worsen leukocytosis in some patients. The primary action of anagrelide is to inhibit megakaryocyte maturation, thereby reducing platelet counts, which makes it more suitable for essential thrombocythemia 1. For severe leukocytosis, particularly in the context of myeloproliferative disorders, hydroxyurea is generally the preferred first-line cytoreductive agent because it can reduce both white blood cell and platelet counts 1.
Some key points to consider in managing severe leukocytosis include:
- Immediate cytoreduction with hydroxyurea at doses of 15-30 mg/kg/day may be necessary for severe leukocytosis, with dose adjustments based on blood count response.
- Leukapheresis may be required before starting cytoreductive therapy in cases of extremely high white counts with symptoms of leukostasis.
- Anagrelide's potential to cause cardiovascular side effects could be particularly problematic in patients with hyperviscosity associated with severe leukocytosis.
- The presence of additional mutations (such as TET2, ASXL1, IDH2, and TP53) in patients with ET may affect the molecular response to treatments like interferon alfa 1.
Given the potential risks and the lack of efficacy of anagrelide in reducing white blood cell counts, hydroxyurea remains the preferred choice for managing severe leukocytosis, especially when considering the need to address both white blood cell and platelet count reductions in myeloproliferative disorders 1.
From the Research
Anagrelide and Severe Leukocytosis
- There is no direct evidence in the provided studies that links anagrelide to severe leukocytosis 2, 3, 4, 5, 6.
- Anagrelide is used to reduce elevated platelet counts in patients with essential thrombocythaemia, and its effects on leukocyte counts are not explicitly mentioned in the studies 2, 3, 4, 5, 6.
- The studies focus on the efficacy and safety of anagrelide in reducing platelet counts and preventing thrombotic events, with some discussing its long-term consequences and comparison to other treatments like hydroxyurea 2, 3, 4, 5, 6.
- One study mentions the development of progressive anemia in patients with CALR mutation, but this is not directly related to leukocytosis 4.
- Another study reports on the long-term use of anagrelide in young patients with essential thrombocythemia, but does not mention severe leukocytosis as a side effect 6.