It is known to interact with nephrotoxic agents (e.g. amphotericin B, foscarnet, IV aminoglycosides, IV pentamide, vancomycin, tacrolimus, non-steroid anti-inflammatory drugs, etc.) to increase their nephrotoxic potential. As it must be given concurrently with probenecid it is advised that drugs that are known to interact with probenecid (e.g. drugs that probenecid interferes with the renal tubular secretion of, such as paracetamol, aciclovir, aminosalicylic acid, etc.) are also withheld. Mechanism of action Its active metabolite, cidofovir diphosphate, inhibits viral replication by selectively inhibiting viral DNA polymerases. It also inhibits human polymerases, but this action is 8–600 times weaker than its actions on viral DNA polymerases. It also incorporates itself into viral DNA, hence inhibiting viral DNA synthesis during reproduction. It possesses in vitro activity against the following viruses: Human herpesviruses Adenoviruses Human poxviruses (including the smallpox virus) Human papillomavirus History Cidofovir was discovered at the Institute of Organic Chemistry and Biochemistry, Prague, by Antonín Holý, and developed by Gilead Sciences and is marketed with the brand name Vistide by Gilead in the US, and by Pfizer elsewhere. Synthesis Cidofovir can be synthesized from a pyrimidone derivative and a protected derivative of glycidol. See also Brincidofovir, a novel prodrug of cidofovir that can be taken orally References Gilead Sciences Anti-herpes virus drugs Pyrimidones Amines Ethers Phosphonic acids Primary alcohols