ABSTRACT
More than 50 years have elapsed since the discovery of the first antiviral agents, i.e. methisazone and 5-iodo-2′-deoxyuridine. In contrast to the evolution in other fields, the antiviral chemotherapy has evolved very slowly at the start. The reasons therefore are multiple:
• close association between the replicative cycle of the virus and the metabolism of the cell;
• the intracellular location of the virus; • viruses possess considerable fewer virus-associated or -encoded enzymes than bacteria; • effective vaccines have been developed for the prevention of some severe viral
infections; and • antiviral research is a high-risk enterprise for industry.
