Antivirals

Question 1

Acyclovir

Answer 1

Guanine analog - chain terminator

First step: Phosphorylation by Viral Thymidine Kinase

Question 2

Valacyclovir

Answer 2

Guanine analog - same as Acyclovir

Orally available

Question 3

Famciclovir

Answer 3

Longer intracellular half life than Acyclovir

VSV

Question 4

IV Acyclovir

Answer 4

Can cause interstitial nephritis or crystalline nephropathy if not hydrated enough

Question 5

Ganciclovir

Answer 5

Activated by Human Thymidine Kinase

CMV

Bone Marrow suppression - could not be used in combination with AZT for HIV CMV retinitis
Nephrotoxicity

Question 6

Cidofovir

Answer 6

Cytosine Analog - chain terminator
Alternative tx for CMV if using AZT
Nephrotoxic

Must be coadministered with Probenecid to prevent uric acid build up (gout)

Question 7

Foscarnet

Answer 7

Pyrophosphate analog - chain terminator
Tx: All Herpes viruses, acyclovir resistance too

Nephrotoxic - Hypokalemia, Hypocalcemia, Mg2+ wasting

Question 8

Ribavirin

Answer 8

Nonsense base - chain terminator

RSV, Hep C

Question 9

Amantidine/Rimantidine

Answer 9

Bind to M2 protein of Influenza A only

Inhibit pH dependent release of ribonucleoproteins from within virally infected cell

Does NOT work for influenza B

SE: Insomnia, Dizziness, Difficulty concentrating

Question 10

Oseltamivir (Tamiflu)

Answer 10

Inhibit Neuraminidase
Prevents cleavage of sialic acid - prevents spread to respiratory tree

Influenza A and B

Question 11

NS5A, NS5B, NS3/4A, Protease

Answer 11

Treatment for Hep C

Targets NON-STRUCTURAL PROTEINS!

Treatment is Genotype specific

Question 12

Harvoni

Answer 12

HepC Treatment

Sofosbuvir (NS5B) + Ledipasvir

Question 13

NS5B

Answer 13

Sofosbuvir

Develop resistance very quickly, worth genotyping to find out