Anagrelide in Essential Thrombocythemia (ET): Results from 150 patients over 25 years by the 'Ph1-negative Myeloproliferative Neoplasms Latium Group'.

BACKGROUND AND AIMS: Anagrelide is a drug effective in reducing platelet counts in Essential Thrombocythemia (ET) and Ph1-negative Myeloproliferative Neoplasms. The aim of this study was to evaluate the real-life use of anagrelide in ET patients followed over 25 years at the Haematological Institutes belonging to "Ph1-negative Myeloproliferative Neoplasms Latium Group". PATIENTS AND METHODS: Eligibility criteria were: diagnosis of ET and treatment with anagrelide. Data were collected through an ad hoc case report form. RESULTS: 150 patients received anagrelide for a median time of 7.4 years (0.1-23.2). Anagrelide was administered as first-line therapy in 34.7% of patients, as second-line in 52% and as third-line in 13.3%: 85.4% responded to therapy. Sixty-eight/136 evaluable patients reported side effects: palpitations, peripheral vasodilation, anaemia, diarrhoea and gastric distress. Fourteen thrombotic (arterial 10, venous 4) and 51 bleeding events (minor 48, major 3) occurred. Sixteen/150 (10.6%) patients developed secondary myelofibrosis and 3/150 (2%) an acute myeloid leukaemia. CONCLUSIONS: In our experience, anagrelide is an effective drug in reducing platelet levels in a high percentage of ET patients. It is especially addressed to younger people. A careful assessment of the thrombotic risk and monitoring of cardiac function, at diagnosis and during follow-up, is mandatory.