A fluid pharmaceutical formulation comprising a liposome in an aqueous medium, the liposome having an aqueous interior space separated from the medium by a membrane comprising one or more lipids, the aqueous interior space comprising a polyanion that is a polyanionized polyol or a polyanionized monosaccharide or disaccharide and a cation that is a cationic antineoplastic therapeutic entity wherein: the liposome lipid and the cationic antineoplastic therapeutic entity are present at an entity to lipid molar ratio of at least 0.1 the formulation has in vivo anti-neoplastic activity at least a four-fold higher than the anti-neoplastic activity of the entity in a free non-liposomal form and toxicity of the formulation administered to a mouse is equal to or less than toxicity, of the entity administered to a mouse in a free non-liposomal form.
