Pharmacology: Pharmacodynamics/Pharmacokinetics: The ferrokinetics of Femorum labelled with 59Fe and 52Fe were assessed in 5 patients with anaemia and chronic renal failure. Plasma clearance of 52Fe was in the range of 60 to 100 minutes. 52Fe was distributed to the liver, spleen and bone marrow. At two weeks after administration, the maximum red blood cell utilisation of 59Fe ranged from 62% to 97%.
Following intravenous injection of a single dose of Femorum containing 100 mg iron in healthy volunteers, maximum iron levels, averaging 538 µmol/1, were obtained 10 minutes after injection. The volume of distribution of the central compartment corresponded well to the volume of plasma (approximately 3 litres).
The iron injected was rapidly cleared from the plasma, the terminal half-life being approx. 6 hours. The volume of distribution at steady state was about 8 litres, indicating a low iron distribution in the body fluid. Due to the lower stability of iron sucrose in comparison to transferrin, a competitive exchange of iron to transferrin was observed. This resulted in iron transport of approximately 31 mg iron/24 h. Renal elimination of iron, occurring in the first 4 h after injection, corresponds to less than 5% of the total body clearance. After 24 h the plasma levels of iron were reduced to the pre-dose iron level and about 75% of the dosage of sucrose was excreted.