Development and comparison of iron dextran products.

Iron dextran complex has existed as a parenteral drug formulation for forty years. Two new formulations of this prodrug became available after an older form was withdrawn from distribution in the United States. Molecular weight, lot-to-lot consistency and thermal stability were examined among these three complex formulations using HP-GPC analysis. Also, particle size measurements using transmission electron microscopy and reduction degradation kinetics were determined. In each mode of analysis, substantial differences were observed among the three preparations with variability and sensitivity to stress (either thermal or acid) decreasing from the oldest form (no longer available) to the next offered complex (Mw of 90 kd +/- 7.5%) to the most recently approved complex (Mw of 265 kd +/- 1.5%). These findings support an iron dextran complex produced by improved techniques and higher manufacturing quality standards with less variability and more reproducibility.