title: Optimizing the dose of hydroxyurea therapy for patients with β-thalassemia intermedia (Hb E-β-thalassemia): a single center study from Eastern India.
abstract: Over the past 20 years, hydroxyurea (HU) has emerged as an important therapeutic agent to augment Hb F and thus total hemoglobin (Hb) in Hb E [β26(B8)Glu→Lys; HBB: c.79G > A]-β-thalassemia (Hb E-β-thal), albeit used in varying doses with little consensus on its optimal dose. We report the interim analysis findings of a broader study to assess the impact of Comprehensive Thalassemia Care, of which the present report was a part. Sixty-one Hb E-β-thal patients who were transfusion independent or requiring occasional transfusions [β-thal intermedia (β-TI)] were randomized to one of two groups; A (n = 32) and B (n = 29) to receive 10 and 20 mg/kg/day HU, respectively. The primary objective of the study was to assess the differences in responses to different doses of HU. Secondary end points were to see the tolerability and safety of HU in different doses. Good response (GR) was defined as a rise of Hb by > 1.0 g/dL; intermediate response (IR) as a rise in Hb by 0.6-1.0 g/dL anytime during the study period. No response (NR): rise in Hb by < 0.5 g/dL in 12 weeks or drop in Hb level from the previous value. Over a follow-up period of 24 weeks, we had 18 (56.2%) GRs, nine (28.2%) IRs and five (15.6%) NRs, while the number of GRs, IRs and NRs in group B were five (17.2%) 12 (41.4%) and 12 (41.4%), respectively. Adverse effects were more common in group B, making this dose (20 mg/kg/day) of HU more myelo-suppressive than Hb F inducing.
authors.affiliation: Institute of Haematology and Transfusion Medicine, Medical College Kolkata , West Bengal , India.
authors.forename: Vinaykumar V
authors.initials: VV
authors.lastname: Bohara
authors.forename: Sudeshna
authors.initials: S
authors.lastname: Ray
authors.forename: Prantar
authors.initials: P
authors.lastname: Chakrabarti
authors.forename: Siddhartha Sankar
authors.initials: SS
authors.lastname: Ray
authors.forename: Uttam Kumar
authors.initials: UK
authors.lastname: Nath
authors.forename: Utpal
authors.initials: U
authors.lastname: Chaudhuri
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006446:Hemoglobin E / Q000235:genetics; D006801:Humans; D006918:Hydroxyurea / Q000008:administration & dosage* / Q000009:adverse effects; D008297:Male; D011446:Prospective Studies; D016896:Treatment Outcome; D055815:Young Adult; D017086:beta-Thalassemia / Q000097:blood / Q000188:drug therapy* / Q000235:genetics
chemical_list: D006446:Hemoglobin E; D006918:Hydroxyurea