Multicenter Study of Hydroxyurea (MSH)

This study aimed to determine whether or not treatment with hydroxyurea titrated to maximum tolerated doses would reduce the frequency of vaso-occlusive (painful) crises by at least 50% in 299 men and women between 18 and 50 years old with a diagnosis of sickle cell anemia by gel electrophoresis conducted by a Core Laboratory. A secondary objective investigated correlations of fetal hemoglobin (HbF) levels and other patient or treatment characteristics with the occurrence of vaso-occlusive (painful) crises, and the effect of treatment on the quality of life.

This controlled trial made hydroxyurea the first drug of proven benefit in preventing vaso-occlusive pain crisis and acute chest syndrome caused by sickle cell disease, with additional findings including reduced mortality in adult patients taking hydroxyurea for frequent painful sickle cell episodes after 9 of years follow-up. No significant side-effects of hydroxyurea therapy were noted.

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