Antivirals

Question 1

Valacyclovir MOA

Answer 1

• guanosine analogue
• must be activated by viral thymidine kinase
• acycloGTP inserted into growing viral DNA chain => stop growth of DNA strand
• also inhibits DNA polymerase
• higher drug levels after oral absorption than acyclovir
• USE: zoster (reduces duration of postherpatic neuralgia) and HSV

Question 2

Acyclovir MOA

Answer 2

• guanosine analogue
• must be activated by viral thymidine kinase
• acycloGTP inserted into growing viral DNA chain => stop growth of DNA strand
• also inhibits DNA polymerase
• USE: herpes family (-CMV and EBV)

Question 3

Amantadine MOA

Answer 3

• inhibits uncoating of Influenza A after it enters cell
• M2 ion channel inhibitor
• USE: influenza A (not B)
  
  • must be given within 48 hrs
  • prophylaxis

Question 4

Oseltamivir MOA

Answer 4

• neuraminidase inhibitor
• prevents viruses from leaving infected cells
• USE: influenza A and B
  
  • must be given within 48 hrs
  • prophylaxis

Question 5

NRTI MOA

Answer 5

Anti-Retroviral

• nucleoside analogue => competitively incorporated into DNA strand =>stops elongation
• must be phosporylated to be activated
• USE: HAART

Question 6

NNRTI MOA

Answer 6

Anti-Retroviral

• binds directly and noncompetitively to reverse transcriptase
• does not need to be phosphorylated to be activated
• USE: HAART

Question 7

Protease Inhibitor MOA

Answer 7

anti-retroviral

• inhibits protease =>virions can’t be chopped from precursor to make viral core =>non-infectious particle
• USE: HAART