Anagrelide in the treatment of essential thrombocythemia

Overview

Essential thrombocythemia is a heterogenous disease from the group of Ph negativemyeloproliferativedisorders. Patients with essential thrombocythemia are at risk for vascular complications (thrombosisand bleeding) and this risk depends on clinical presentation of the disease. Heterogenous is alsoresponse of this disorder to the therapy. Most of the symptomatic or otherwise high-risk patients inCzech republic are currently treated with hydroxyurea or alpha-interferon, but the probability ofresponse to the particular agent and frequency and severity of adverse events are not possible to predictat advance. Anagrelide is a drug selectively lowering the number of platelets in patients with myeloproliferativedisorders, without significant effect on other haematopoietic cell lines. This drug isvaluable not only for treatment of patients with ET resistant to other agents but because its favourableprofile of adverse effects and absence of leukemogenicity it is increasingly being used as a drug of firstchoice in patients with essential thrombocythemia. In the following review,we compare the mechanismof action and effectivity of anagrelide with those of hydroxyurea and interferon. Furthermore, wepresent our own experience with anagrelide in the treatment of patients with essential thrombocythemia.

Key words:
essential thrombocythemia, treatment, hydroxyurea, alpha-interferon, anagrelide.