6/28/23, 12:39 AM ANAHYDRET Pathway Feedback Search Clinical Topics Home Studies ANAHYDRET ANAHYDRET Disease Essential thrombocythemia Trial question Is anagrelide noninferior to hydroxyurea in patients with essential thrombocythemia? Study design Multi-center Single blinded RCT Population Characteristics of study participants 64.0% female N = 259 36.0% male 259 patients (165 female, 93 male) Inclusion criteria: patients with essential thrombocythemia who have high-risk profile Key exclusion criteria: pregnancy, contraindications to the study drugs, known lactose intolerance, severe renal disease, severe liver disease, coexisting malignancy, or systemic diseases Interventions N=122 anagrelide (started at a dose of 1.0 mg/day during the first week and adjusted until maintenance of the platelet count at normal or close to normal levels) N=137 hydroxyurea (started at a dose of 1,500 mg/day and adjusted until maintenance of the platelet count at normal or close to normal levels) Primary outcome https://web.pathway.md/studies/recO6WNolUacnItUm 1/2 6/28/23, 12:39 AM ANAHYDRET Pathway ET-related major and minor thrombohemorrhagic events at 6 months 29.0 events 29 22 21.8 events 14.5 events Difference not exceeding nonferiority margin 7.3 events 0.0 events Anagrelide Hydroxyurea Difference not exceeding nonferiority margin in ET-related major and minor thrombohemorrhagic events at 6 months (22 events vs. 29 events; HR 1.19, 95% CI 0.61 to 2.3) Secondary outcomes No significant difference in ET-related major and minor thrombohemorrhagic events at 12 months (33 events vs. 31 events; HR 1.03, 95% CI 0.57 to 1.81) No significant difference in ET-related events, after 36 months (51 events vs. 47 events; HR 0.92, 95% CI 0.57 to 1.46) No significant difference in the rate of no ET-related thrombotic or bleeding events after observation of up to 6 years (63.9% vs. 67.4%; HR 0.92, 95% CI 0.57 to 1.5) Safety outcomes No significant difference in adverse events and adverse events leading to discontinuation of drugs. Significant differences in anemia (9.0% vs. 18.3%), leukopenia (0.8% vs. 28.2%), palpitations (24.6% vs. 2.3%). Conclusion In patients with essential thrombocythemia who have high-risk profile, anagrelide was noninferior to hydroxyurea with respect to a ET-related major and minor thrombohemorrhagic events at 6 months. Reference Gisslinger H, Gotic M, Holowiecki J et al. Anagrelide compared with hydroxyurea in WHO-classified essential thrombocythemia: the ANAHYDRET Study, a randomized controlled trial. Blood. 2013 Mar 7;121(10):1720-8. Open reference URL https://web.pathway.md/studies/recO6WNolUacnItUm 2/2