ANTIVIRAL CHEMOTHERAPY - MECHANISM OF ACT ION, ACTIVITY EVALUATION, RESISTANCE AND FURTHER DEVELOPMENTS

Antiviral chemotherapy is based on the selective inhibition of intrace llular virus multiplication. Inhibitors of viral DNA polymerases perfe ctly exemplifies this mode of action. In spite of their selectivity, s ome of these drugs are cytotoxic and all remain unefficient against la tent viruses. Evaluation of antiviral activity requires in vitro sensi tivity tests, in vivo studies on animals and virological analyses duri ng clinical trials. This evaluation needs well standardized assays. Th e emergence of in vitro resistance reflects the occurrence of mutation s regarding target enzymes. Clinical significance of antiviral drug re sistance needs to be assessed in many circumstances, even if its assoc iation with immunodeficiency often leads to a clear therapeutic failur e. Further developments will include the synthesis of novel inhibitors , study of drug associations and improvement of virological diagnosis techniques relevant to therapy.