section name header

Evidence summaries

Hydroxyurea in the Treatment of High-Risk Essential Thrombocythaemia

Hydroxyurea plus low-dose aspirin appears to be more effective than anagrelide plus low-dose aspirin for patients with essential thrombocythaemia and high risk for vascular events. Level of evidence: "B"

A total of 809 patients with essential thrombocythaemia who were at high risk for vascular events (age at least 60 years, platelet count>1000, history of thrombosis, haemorrhage, hypertension, diabetes) were randomized to receive either hydroxyurea or anagrelide at a dose that maintained the platelet count under 400 1. All patients received aspirin 75-100mg/day. The risk of a composite primary end point (myocardial infarction, unstable angina, cerebral ischaemia, peripheral arterial trombosis, venous thrombosis, serious haemorrhage or death from thrombotic or haemorrhagic causes) was higher with anagrelide than with hydroxyurea (OR 1.57, 95% CI 1.04 to 2.37). Anagrelide was associated with increased rates of arterial thrombosis, serious haemorrhage, and transformation to myelofibrosis, but decreased rates of venous thombosis.

    References

    • Harrison CN, Campbell PJ, Buck G, Wheatley K, East CL, Bareford D, Wilkins BS, van der Walt JD, Reilly JT, Grigg AP, Revell P, Woodcock BE, Green AR, United Kingdom Medical Research Council Primary Thrombocythemia 1 Study. Hydroxyurea compared with anagrelide in high-risk essential thrombocythemia. N Engl J Med 2005 Jul 7;353(1):33-45. [PubMed]

Primary/Secondary Keywords