This trial began in 1978. Its forerunner was a study involving both deferoxamine and ascorbic acid. Although ascorbic acid promotes iron removal, its administration was followed by cardiac deterioration in several patients. In this study, patients receiving subcutaneous deferoxamine were randomized to receive either ascorbic acid or placebo, thereby providing a controlled test of this agent in treatment of iron overload. Sixty-five patients with homozygous beta-thalassemia participated in the long-term chelation trial. Of these, 49 were randomized to the ascorbic acid trial.