Mean net iron excretion in C apella monkeys with iron overload (see text) after administration of DFO or HBED. The primates were administered (A) DFO 300 μmol/kg PO, (B) HBED 324 μmol/kg PO, (C) DFO 150 μmol/kg sc, (D) HBED 150 μmol/kg sc, (E) DFO 300 μmol/kg sc, (F) HBED 324 μmol/kg sc, (G) HBED 81 μmol/kg sc, (H) HBED 75 μmol/kg sc for three doses (225 μmol/kg total), and (I) HBED 162 μmol/kg sc for two doses (324 μmol/kg total). Animals in groups B, F, G, and I received the HBED monohydrochloride dihydrate in 0.1 mmol/L sodium phosphate buffer at pH 7.6, whereas those in groups D and H were administered the HBED monosodium salt in saline at pH 7.3. Excretion is shown as μg iron/kg body weight on the scale of the left vertical axis. For comparative purposes, the result of our previously published study26 of the sc administration of DFO 150 μmol/kg to C apella monkeys with a similar magnitude of iron overload is shown and is indicated by an asterisk.