Resistance to acyclovir is most commonly due to mutation in a viral gene that encodes a protein that:
(Ref: KDT 6/e p768) Nucleoside/tide analogues (like acyclovir) act by conveing to NTPs. First phosphorylation step occurs inside the virs and resistance occurs if there is mutation in this gene.
Conves viral RNA into DNA
Phosphorylates acyclovir
transpos acyclovir into the cell
Transpos acyclovir out of the cell
Other topics and Adverse effects