TLR4 and neoplasm: In order to enhance cidofovir-induced tumor control, the drug was combined with the immune adjuvants that are used in the currently approved HPV vaccines, i.e. aluminum hydroxyphosphate sulfate (in Gardasil and Cervarix vaccines) and ASO4 (in Cervarix vaccine), a combination of aluminum hydroxide (Alum) and 3-O-desacyl-4’-monophosphoryl lipid A (MPL), a TLR4 ligand.