Antiviral susceptibility of recombinant Herpes simplex virus 1 strains with specific polymerase amino acid changes

Acyclovir (ACV) and penciclovir and their prodrugs are recommended for therapy or prophylaxis of Herpes simplex virus 1 (HSV-1) infections. Their administration, however, can lead to the emergence of resistant strains with altered viral thymidine kinase (TK) function, especially in immunocompromised patients. Furthermore, amino acid (aa) changes of the viral deoxyribonucleic acid polymerase (POL) may contribute to resistance to the aforementioned nucleoside analogues. Given this, treatment with foscarnet (FOS) or cidofovir (CDV) may represent an important alternative. Both drugs directly affect POL activity.