A long-term study of young patients with essential thrombocythemia treated with anagrelide.

Abstract

BACKGROUND AND OBJECTIVES:

Essential thrombocythemia (ET) can be complicated by life-threatening thrombosis and has a risk of converting into acute leukemia. Cytoreductive therapy may reduce the risk of thromboembolic complications. Herein, we report the results of a long-term study of patients with ET treated with anagrelide to control thrombocytosis.

DESIGN AND METHODS:

Thirty-nine (34 evaluable) patients (median age, 33 years; 24 previously untreated) were enrolled between 1989-1996; the mean platelet count prior to therapy was 1197x10(9)/L. Only 9 out of 34 evaluable patients were at high risk of thrombosis (platelet count more than 1500x10(9)/L). The initial dose of anagrelide (0.5 mg/bid for 7 days) was increased by 0.5 mg/day (maximum dose: 3 mg/day) until a response was seen.

RESULTS:

A complete response (platelets < 450x10(9)/L for >1 month) was seen in 15 /34 (44%) patients and a partial response (platelets 450-600x10(9)/L for >1 month) was seen in 17/34 ( 50%), so that the some kind of response was seen in 32/34 (94%) of the patients at a median time of 4.2 months after starting treatment. Seventeen patients (50%) are still being treated and have achieved platelet control for a maximum follow-up of 12.5 years. Late onset anemia occurred in 4/39 patients. Three out of 39 patients (8%) had cardiac disorders.

INTERPRETATION AND CONCLUSIONS:

Anagrelide appears suitable for controlling thrombocytosis in ET patients over the long-term. This drug may be used in patients younger than 60 years, with the exclusion of women of child-bearing potential and subjects aged 40-60 years with a history of major thrombotic events. Anagrelide should not be administered to patients with cardiac disorders, and a careful approach to patients should include monitoring of heart function before and during treatment.

• Authors: Maria Gabriella Mazzucconi, Roberta Redi, Sayla Bernasconi, Luisa Bizzoni, Francesco Dragoni, Roberto Latagliata, Cristina Santoro, Franco Mandelli
• Journal: Haematologica (Haematologica) Vol. 89 Issue 11 Pg. 1306-13 (Nov 2004) ISSN: 1592-8721 [Electronic] Italy
• PMID: 15531452 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Hemoglobins
• Platelet Aggregation Inhibitors
• Quinazolines
• anagrelide

Topics

• Adult
• Anemia (chemically induced)
• Female
• Hemoglobins (analysis)
• Humans
• Male
• Middle Aged
• Platelet Aggregation Inhibitors (adverse effects, therapeutic use)
• Quinazolines (adverse effects, therapeutic use)
• Stomach Diseases (chemically induced)
• Tachycardia (chemically induced)
• Thrombocythemia, Essential (drug therapy)
• Time Factors