Antiviral [20]

Question 1

3 DNA viruses

Answer 1

Adenovirus
Herpesvirus
Papilomavirus

Question 2

2 RNA viruses

Answer 2

Influenza virus
Retrovirus (AIDS)

Question 3

Explain virus replication cycles

Answer 3

1. Attachment to host cell
2. Un-coating of virus
3. Control of DNA/RNA/protein production
4. Production of viral subunits
5. Assembly of virions
6. Release of virions (cell lysis)

Question 4

Describe specificity of antiviral drugs

Answer 4

Hard to achieve distributional selectivity
Target enzymes, metabolic pathways, viral Nucleic acid synthesis

Question 5

3 viral specific targets of antivirals

Answer 5

Viral cell binding
Interrupting uncoating
Stimulating host immune system

Question 6

What is viral latency

Answer 6

Recurrence of infection
(Acute, persistent, reactivating, slow)

Question 7

Are most AV drugs virustatic or viruscidal

Answer 7

Virustatic
No AV drugs can eliminate latency

Question 8

Acute virus infection example

Answer 8

Influenza

Question 9

Persistent virus infection example

Answer 9

Meningitis

Question 10

Reactivating virus infection example

Answer 10

Herpes

Question 11

Slow virus infection example

Answer 11

HIV

Question 12

What increases AV resistance

Answer 12

Rapid replication rates
Spontaneous mutation
Mutations prevent protease and reverse transcriptase binding

Question 13

Traits of herpes virus

Answer 13

Cold sores, varicella zoster (chicken pox), Epstein Barr (glandular fever)

Blisters

Infects sensory ganglia where becomes latent

Question 14

Herpes treatment

Answer 14

Aciclovir
Synthetic guanosine analogue
High specificity to simplex
Require intracellular phosphorylation to become active

Question 15

Aciclovir activation

Answer 15

Uses simplex’s thymidine kinase to monophosphorylate Aciclovir

Host cell kinases di and tri phosphorylate

Triphosphate form is active

Question 16

Aciclovir MOA

Answer 16

G analogue so binds DNA
Makes a kink
DNA polymerase can’t cause elongation

Question 17

HIV and AIDS general information

Answer 17

1981 discovery
Sexually transmitted
Destruction of host immune system
HIV1 - AIDS
HIV2 - less virulent

Question 18

HIV MOA

Answer 18

Viral DNA -(RNA polymerase)-> viral RNA —> translation to viral components —> viral assembly —> host cell death

Question 19

What does HIV target

Answer 19

CD4 and CD8 cells

Question 20

HIV treatments

Answer 20

Fusion inhibitors
CCR5 inhibitors
NRTIs and NNRTIs
Protease inhibitors

Question 21

Example of fusion inhibitors

Answer 21

Enfurvitide

Question 22

Fusion inhibitor MOA

Answer 22

Identical to HIV gp41
Stops gp41 changing shape to allow HIV to enter host cell
Inhibits fusion of cellular and viral membranes

Question 23

CCR5 inhibitor example

Answer 23

Maraviroc

Question 24

CCR5 inhibitor MOA

Answer 24

Binds CCR5 receptor on CD4
Prevents interaction of gp120 and CCR5
Needed for entry to cell
Not a first line therapy

Question 25

Example of nucleoside reverse transcriptase inhibitors NRTIs

Answer 25

Zidovudine

Question 26

NRTI MOA

Answer 26

Inhibits viral reverse transcriptase Active when in triphosphate form Triphosphate competes for proviral synthesis Termination of viral DNA elongation

Question 27

Indications of NRTIs

Answer 27

Advanced HIV infection

Question 28

Adverse effects of NRTIs

Answer 28

Headaches Nausea Anaemia

Question 29

What is zidovudine structurally similar to

Answer 29

Thymidine

Question 30

Non nucleoside reverse transcriptase inhibitors NNRTIs MOA

Answer 30

Doesn’t look like nucleotide Denatures reverse transcriptase

Question 31

NNRTI example

Answer 31

Nevirapine

Question 32

Protease inhibitor example

Answer 32

Ritonovir

Question 33

Protease inhibitor MOA

Answer 33

Inhibition of virus protease Protease essential for post-translational processing of gag and gag-pol poly proteins into functional proteins

Question 34

Protease inhibitors clinical pharmacology

Answer 34

Highly effective in suppressing viral load CYP450 interactions Resistance issues

Question 35

Highly active anti-retroviral therapy (HAART)

Answer 35

NRTI + NNRTI or PI

Question 36

What is atripla

Answer 36

One combination pill per day

Question 37

What is given to HIV patients with resistant strains of HIV

Answer 37

Integrase inhibitors (Raltegravir) Inhibits integration or transcribed viral DNA into host cell chromosomes