Antivirals

Question 1

What is the basic MoA of Acyclovir?

Answer 1

Attaches to DNA sequences and then blocks the addition of any new bases to attach to the chain - halting DNA synthesis

Question 2

Acyclovir is metabolically inert. What has to happen for it to become active?

Answer 2

1. It has to get to it’s active form, Acyclovir Triphosphate, via acquisition of three phosphate groups:

• Cannot be phosphorylated by eukaryotic cells (viral selectivity)
• If a virus is present that has the enzyme (thymidine kinase) to phosphorylate, then it will get phosphorylated and activated.

Question 3

Ganciclovir is used primarily to treat what kinds of viruses?

Answer 3

Herpes viruses - especially cytomegalovirus