Antivirals

Question 1

Amantadine MOA and Use

Answer 1

blocks attachment, penetration, and uncoating of Influenza A

use: prophylaxis, reduces duration of flu by 1-2 days

Question 2

SE of Amantadine

Answer 2

atropine-like peripheral effects, livedo reticularis

Question 3

Enfuvirtide MOA and use

Answer 3

binds gp41 and inhibits fusion of HIV1 to CD4 cells (chemokine receptor but drug is large enough to block gp120 which blocks fusion)

Question 4

Maraviroc moa and use

Answer 4

blocks CCR5 protein on T cell membrane to prevent viral entry
use: HIV

Question 5

Acyclovir moa

Answer 5

phosphorylation by THYMIDINE KINASE –> incorporated into DNA molecule–> chain terminator (lacks 3’OH)
*inhibits DNA polymerase

Question 6

Acyclovir resistance

Answer 6

changes in DNA polymerase or decreased TK activity

Question 7

Acyclovir uses

Answer 7

HSV

VZV

Question 8

Why might a patient need multiple treatments with acyclovir?

Answer 8

it only works on dividing virus so if it is dormant, it is not killed

Question 9

SE of Acyclovir

Answer 9

crystalluria, neurotoxicity

* NOT hematotoxic

Question 10

Name the viral DNA polymerase inhbitors

Answer 10

acyclovir
famciclovir
valacyclovir
ganciclovir
foscarnet
**pro-drugs

Question 11

What are the newer versions of acyclovir? Why would you use them?

Answer 11

famciclovir
valacyclovir
longer t1/2 than acyclovir
may work on acyclovir resistant strains as long as they have TK

Question 12

Gancyclovir use

Answer 12

HSV, VZV: uses Tk for phosphorylation
CMV: uses phosphotransferase
**prophylaxis and tx of CMV in AIDS and transplantation

Question 13

Gancyclovir SE

Answer 13

dose limiting hematotoxicity (leukopenia), mucositis, fever, rash, crystalluria (nephrotox), seizures (neurotox)

Question 14

Foscarnet MOA

Answer 14

NOT an anti-metabolite
blocks DNA and RNA polymerases
*doesn’t require TK

Question 15

Foscarnet use

Answer 15

acyclovir-resistant HSV

CMV, VZV

Question 16

Foscarnet SE

Answer 16

dose limiting acute tubular necrosis, hypocalcemia

Question 17

Foscarnet drug interactions?

Answer 17

Pentamidine, will cause hypocalcemia

furosemide

Question 18

Ribivarin MOA

Answer 18

monophosphorylase inhibits IMP dehydrogenase, triphosphorylated inhibits viral RNA polymerase

Question 19

Ribivarin SE

Answer 19

hematotoxic, upper airway irritation, teratogenic!

Question 20

Ribivarin use

Answer 20

adjunct to alpha interferon 
Hep C
RSV
Lassa fever
hantavirus

Question 21

What is an NRTI?

Answer 21

nucleoside reverse transcriptase inhibitor
pro-drugs
chain terminators
activated by nonspecific kinases
use with protease inhib. --> HAART

Question 22

What is HAART?

Answer 22

highly active acute retroviral therapy

uses NRTI + protease inhibitor

Question 23

What is the moa of NRTIS?

Answer 23

competes with natural nucleotides to inhibit reverse transcriptase and can also be incorporated into DNA to cause chain termination

*all work in the same way just with different base analogs

Question 24

NRTI resistance?

Answer 24

mutation in gene for reverse transcriptase

there isn’t complete cross resistance between different NRTIs

Question 25

Zidovudine

Answer 25

NRTI | SE: bone marrow suppression (SEVERE), headaches, fatigue, myalgias

Question 26

Other names for Zidovudine

Answer 26

Azidothymidine, ZDV, AZT

Question 27

Didanosine names and SE

Answer 27

DD1 | SE: pancreatitis, peripheral neuropathy

Question 28

Abacavire

Answer 28

NRTI SE--> allergies aka: ABC

Question 29

zalcitabine

Answer 29

``` NRTI aka: DDC SE: peripheral neuropathy pancreatitis *don't combine with didanosine ```

Question 30

lamivudine

Answer 30

NRTI aka: 3TC SE: least toxic, some GI sx also used in Hep B

Question 31

Emtricitabine

Answer 31

newer, more active version of lamivudine | aka FTC

Question 32

Stavudine

Answer 32

NRTI aka: D4T dont use with AZT because they have the same base analog Se: myelosuppression, peripheral neuropathy

Question 33

NNRTI

Answer 33

not pro-drugs no myelosuppression additive/ synergistic with NRTIs

Question 34

Nevirapine

Answer 34

NNRTI single does at delivery decreases transmission of HIV from mom to baby (vertical transmission) by 50% CYP450 inducer SE: rash, increased LFT

Question 35

Efavirenz

Answer 35

NNRTI | SE: insomnia, nightmares (dysphoric dreams)

Question 36

Viral aspartate protease inhibitors moa

Answer 36

aspartate protease enzyme contains dipeptide structure that isn't human form so it binds here to inhibit it

Question 37

Viral aspartate protease inhibitors resistance

Answer 37

point mutations in pol gene, incomplete cross resistance

Question 38

Common SE of Viral aspartate protease inhibitors

Answer 38

disordered lipids and carb metabolism with central adiposity and insulin resistance *less with atazanavir

Question 39

Indinavir

Answer 39

Viral aspartate protease inhibitor used most frequently SE: crystalluria

Question 40

Ritonavir

Answer 40

Viral aspartate protease inhibitor used most frequently SE: major drug interactions from P450 induction

Question 41

Saquinavir

Answer 41

Viral aspartate protease inhibitors least toxic low bioavailability predisposes to resistance

Question 42

viral neuraminidase inhibitors

Answer 42

influenza A and B decreases liklihood that virus will penetrate uninfected cells use: prophylaxis may decrease flu sx SE: flu sx

Question 43

Raltegravir

Answer 43

integrase inhib. prevents integration of viral genome into host DNA Use: HIV

Question 44

Human interferons use

Answer 44

Hep B, C, D (alpha interferon) Kaposi sarcoma, CML, MM, RCC (alpha) MS (beta) Chronic granulomatous disease (gamma)