Disclosed is a formulation of canfosfamide consisting essentially of (50±5) mg/mL canfosfamide hydrochloride in (100±10) mM aqueous sodium citrate buffer at pH 4.6±0.2. Also disclosed is a formulation consisting essentially of 50 mg/ mL canfosfamide hydrochloride, 100 mM sodium citrate dihydrate, and 2.9 mM citric acid monohydrate in water at pH 4.6±0.2.