ACYCLOVIR: Resistance Develops as mutations in genes encoding viral TK(mostly) and dNa polymerase TK-dependent resistance is cross-reactive with resistance to valacyclovir, Famciclovir and ganciclovirACYCLOVIR: Resistance • Develops as mutations in genes encoding viral TK (mostly) and DNA polymerase. • TK-dependent resistance is cross-reactive with resistance to Valacyclovir, Famciclovir, and Ganciclovir