The present disclosure concerns complexes of 4-hydroperoxy ifosfamide. In one embodiment the complexes can be represented by the formulawherein A represents an ammonium species selected from the conjugate acid of a basic amino acid, quaternary ammonium, aliphatic ammonium, heterocyclic ammonium, aromatic ammonium, substituted and unsubstituted pyridinium, guanidinium, and amidinium, and wherein X and Y independently represent leaving groups. Also disclosed herein are methods for making such compounds and formulating pharmaceutical compositions thereof. Methods for administering the disclosed compounds to subjects, particularly to treat hyperproliferative disorders, also are disclosed.
