Antiviral Drugs

It's very difficult to kill something that isn't dead. This is the challenge when developing antiviral drugs. Whether or not a virus is alive is a great issue of debate among scientists. Amantadine was the first licensed antiviral drug in the U.S. but how it works is not well known. It has limitations in preventing influenza. Other antiviral drugs for the the treatment of the flu ar zanamivir (Relenza) and oseltamivir phosphate (Tamiflu). Both of these drugs are inhibitors of neuraminidase, an enzyme critical for a virus to continue to reproduce. Because a virus is a biochemical mass of protein and nucleic acid, most antiviral drugs are synthetic nucleosides that interfere with DNA or RNA sysnthesis. The HIV virus uses an enzyme called reverse transcriptase to reproduce itself. Drugs such as zidovudine, didanosine, and zalcitabine block the activity of this enzyme. Companies like Axygen, Beckman Coulter, and Whatman provide products used in antiviral drug research.