Antiviral Drugs

Front 1

What is the first line of defense against influenza?

Back 1

Immunization

Front 2

What drug (on the drug list) blocks the uncoating of the influenza viral RNA inside the human cells by interferring w/ the function of the viral M2 protein which functions as an ion channel?

Back 2

Rimantadine

*Prophylaxis

Front 3

What type of influenza is Rimantadine effective against?

Back 3

Influenza A only

Front 4

What drug (on the drug list) blocks the release of new viral particles from the infected cells via the inhibiton of viral neuraminidase?

Back 4

Oseltamivir

Front 5

What types of influenza is Oseltamivir active against?

Back 5

Influenza A & B

Front 6

What currents strains of influenza are still susceptible the neuraminidase inhibitors?

Back 6

H5N1 & H1N1

Front 7

What vaccine against varicella-zoster virus decreases the incidence of shingles by 50% and causes a 66% decrease in the indicence of post-herpetic neuralgia in patients who still develop shingles?

Back 7

Zostavax

Front 8

What does CMV cause in AIDS patients?

Back 8

Retinitis

Front 9

What drug is used to treat infections caused by HSV and VZV, has a F of 15-20% and comes in i.v. and topical forms?

Back 9

Acyclovir

Front 10

What is the DOC for HSV-1 and HSV-2? What is the F and route of administration?

Back 10

Valcyclovir: prodrug that is converted to Acyclovir

F= 48% p.o. dosing

Front 11

What is the benefit of Valacylovir over Acyclovir?

Back 11

Oral Valacyclovir results in plasma concentrations that are 3-5 X greater than those achieved w/ oral Acyclovir

Front 12

Should the dose of Valcyclovir be increased/decreased in patients w/ renal failure?

Back 12

Decreased

Front 13

What drug is used p.o. to treat HSV and VZV and is converted into the active drug penciclovir?

Back 13

Famciclovir

Front 14

What is the DOC for CMV retinits? What is the F? What are the other routes of administration?

Back 14

1. Ganciclovir
2. F = 6-9% low
3. i.v., ocular implant

Front 15

What is a p.o. drug for CMV retinitis with a F= 60%?

Back 15

Valganciclovir

Front 16

What is a drug (i.v. only) used to treat CMV retinitis?

Back 16

Foscarnet

Front 17

What drug can be given via intravitreal injection to treat CMV retinitis?

Back 17

Fomivirsen

Front 18

What is the MOA of Acyclovir, Valacyclovir, Penciclovir (famciclovir), Ganciclovir, and Valganciclovir?

Back 18

Inhibition of viral DNA polymerase

*not effective against non-replicating, latent viruses

Front 19

What must happen to Acyclovir and Ganciclovir in order for these drugs to be converted into active metabolites?

Back 19

Phosphorylated three times

*drugs are guanosine analogs

Front 20

A herpes virus-specific _____________ ____________, which is found only in infected cells, produces acyclo-monophosphate. The _______________ of the host cells produce the diphosphate and triphosphate forms of acyclovir and ganciclovir that compete with ______ at the viral DNA polymerase which causes _____________ ____________.

Back 20

1. Thymidine Kinase
2. Phosphorylase enzymes
3. dGTP
4. Chain termination

Front 21

What is the most common mechanism of resistance to Acyclovir?

Back 21

Mutation of the viral Thymidine Kinase which prevents the conversion of Acyclovir to Acycolvir monophosphate

Front 22

What is the MOA of Foscarnet?

Back 22

Inorganic pyrophosphate which acts directly to inhibit viral DNA and RNA polymerase and HIV RT

*no activation via host cell enzymes is required

Front 23

What are the therapeutic uses of Foscarnet?

Back 23

1. Treat Acyclovir resistant HSV & VZV

2. Treat CMV resistant to Ganciclovir and Cidofovir

Front 24

What is the MOA of Fomivirisen?

Back 24

Antisense oligonucleotide which binds to mRNA and prevents viral replication

*given by intraocular injection

Front 25

What is the MOA of Trifluridine?

Back 25

Converted to trifluridine triphosphate by host-cell enzymes, the active metabolite inhibits viral DNA synthesis

Front 26

What is the therapeutic use of Trifluridine?

Back 26

Ocular drops are used to treat Herpes Keratitis

Front 27

What are the S/E of Acyclovir & Valacyclovir?

Back 27

N/V, diarrhea & headache

Front 28

HIV is a DNA/RNA _________________ that invades ________ cells

Back 28

RNA Retrovirus

CD4+

Front 29

What are the goals of therapy for HIV infection?

Back 29

1. Suppress the viral RNA load to below undetectable values
(<50 copies/ml) for as long as possible

2. Restore and maintain immune function

3. Prevent the development of resistance to antiviral drugs

Front 30

No detectable HIV virus should occur after ___________ months of therapy

Back 30

4-6

Front 31

What is the MOA of Enfuvirtide?

Back 31

Synthetic peptide which blocks the fusion of the viral & T-cell membranes, so HIV cannot enter the CD4+ cell

Front 32

What is the route of administration of Enfuvirtide and the half-life?

Back 32

s.c.

4 hours

Front 33

Enfuvirtide shows no ___________ ___________ with other classes of antiretroviral drugs.

Back 33

cross resistance

Front 34

What is the use of Enfuvirtide?

Back 34

Treat pts. who exhibit high viral loads despite continued therapy with other drugs for HIV infection

Front 35

What is the MOA of Nucleoside RT inhibitors (NRTI's)?

Back 35

Nucleosides are converted to "false" nucleotides (triphosphates) by intracellular kinases

"false" nucleotides competitively inhibit HIV RT and cause chain termination of the viral DNA

These "false" nucleotides can also be incorporated into the viral DNA

Front 36

Which drugs are NRTI's (on the drug list)?

Back 36

Zidovudine
Lamivudine
Abacavir
Tenofovir

Front 37

Which NRTI's do you give together for post-exposure prophylaxis?

Back 37

Zidovudine + Lamivudine

Front 38

What NRTI is often effective when the HIV has become resistance to NRTI's?

Back 38

Tenofovir

Front 39

What is the MOA of NNRTI's?

Back 39

Directly inhibit reverse transcriptase to stop HIV replication

*does not require phosphorylation to be active inhibitors
*binds to different site than that of the NRTI

Front 40

What are the net effects of NNRTIs?

Back 40

Blockade of both RT and DNA polymerase

Front 41

What are the NNRTI's (on the drug list)?

Back 41

Nivirapine

Efavirenz

Front 42

What is the MOA of Raltegravir?

Back 42

Blockade of viral integrase prevents the insertion of viral DNA into human DNA

INTEGRASE INHIBITOR

*p.o.

Front 43

What is the therapeutic use of Raltegravir?

Back 43

MDR HIV infections

Front 44

What is the MOA of Protease inhibitors?

Back 44

Block viral protease to prevent the cleavage of viral polyproteins into the final structural proteins needed for the assembly of the mature virion core required for infectious particles

Front 45

What drugs are Protease Inhibitors?

Back 45

Saquinavir & Ritonavir & Lopinavir

Front 46

What is the use of Ritonavir?

Back 46

A substrate and inhibitor of CYP3AV:
-pharmacokinetic enhancer
-inhibits the enzyme that metabolizes saquinavir
-a small daily dose of ritonavir decreases the daily dose of saquinavir needed to maintain an effective plasma concentration of saquinavir

Front 47

Ritonavir decreases the ___________ ___________ of Saquinavir/Lopinavir so the daily maintenance dose of Saquinavir/Lopinavir can be _____________

Back 47

Hepatic Clearance

Reduced