Antiviral Therapy (non HIV)

Question 1

What are the drugs that Inhibit influenza Neuraminidase?

Answer 1

Zanamivir, Oseltamivir

Inhibit neuraminidase which blocks RELEASE OF PROGENY

Treat and prevent Flu A and B

Question 2

What is Ribavirin
MOA
Use
SE

Answer 2

Reba Sings in the Key of C, but not G

Blocks synthesis of G nucleotides by competitively blocking INOSINE MONOPHOSPHATE DEHYDROGENASE

Used:
RSV
Chronic Hep C

SE
Hemolytic Anemia…Severe Teratogen

Question 3

What is Acyclovir, Famciclovir, and Valacyclovir used for?
MOA
Use
SE

Answer 3

NucleoSide Analogs

Gets monoPO4’d by HSV /VZV THYMIDINE KINASE then PO4’d by infected cell kinases
not PO4’d by uninfected cells

G analog, so is turned to GMP by thymidine kinase, but turned to GTP by CELLULAR enzymes.

Inhibits viral DNA polymerase by chain termination

Use: HSV, VZV, weakly against EBV. None for CMV

Oral and genital herpes and encephalitis
Prophylaxis in immunocompromised

No effect on latent herpes or VSV

Valacyclovir (prodrug of acyclovir) has better oral bioavailability

SE: Obstructive crystalline Nephropathy and acute renal failure if not hydrated

Resistance: Mutated viral thymidine kinase

Question 4

Ganciclovir
MOA
Use
SE

Answer 4

Nucleoside Analog
This is ur CMV drug esp for immunocompromised
G analog–>GMP via CMV kinase–>GTP via cellular kinases

Inhibits viral DNA polymerase

Valganciclovir (prodrug of ganciclovir) has better oral bioavailability

SE: Leuko, neutro, and thrombo cytopenia, renal tox

More toxic to host than acyclovir

Resistance: Mutated CMV viral kinase or lack of it

Question 5

Foscarnet?
MOA
Use
SE

Answer 5

PyroFOSphate analog

NO ACTIVATION NEEDED. Don’t need no stinking viral kinase

Blocks viral DNA polymerase by binding to the enzymes pyrophosphate binding spot

Use: CMV retinitis in immunocompromised when ganciclovir doesn’t work, and for acicyclovir resistant herpes

SE: Nephrotox

Resistance: Mutated DNA polymerase

Question 6

Cidofavir, Tenofovir
MOA
Use
SE

Answer 6

NucleoTide Analogs
Preferentially inhibit viral DNA polymerase. NO PO4’N needed by viral kinase, BUT STILL NEED TO BE PO4’D BY HOST CELL KINASE!!

Use: CMV retinitis in immunocompromised, acicyclovir resistant herpes, LONG HALF LIFE

Nephrotox so co-admin with PROBENECID and IV saline to reduce toxicity

Question 7

What are the interferons
MOA
Use
SE

Answer 7

Glycoproteins synthesized by viral infected cells that warn neighboring cells that a virus is around

IFN-a
Chronic Hep B and C
Karposi
Hairy Cell
Condyloma Acuminatum
Renal Cell CA
Malignant Melanoma

IFN-B
MS

IFN-y
CGD

SE: Neutropenia, Myopathy