Exam II

Question 1

What are the three other names for Acyclovir?

Answer 1

Acycloguanosine, zovirax, valtrex

Question 2

What is the generic name for Zovirax

Answer 2

Acyclovir

Question 3

What is the generic name for Valtrex

Answer 3

Acyclovir

Question 4

Why isn’t acyclovir toxic to normal cells?

Answer 4

because it needs an enzyme from the herpesvirus itself to become phosphorylated and activated

Question 5

name the drug that is a synthetic nucleoside analog of deoxyguanosine

Answer 5

acyclovir

Question 6

true or false: selective toxicity limits the use of antiviral drugs?

Answer 6

true; the drug must be harmful to the agent but not to the host

Question 7

what is acyclovir used to treat?

Answer 7

herpesvirus

Question 8

true or false: acyclovir is an inactive prodrug?

Answer 8

true; it must be phospohorylated by a herpes enzyme and then by the host to become activated

Question 9

How many kinases are required to activate acyclovir?

Answer 9

3

Question 10

Name the kinases needed to activate acyclovir

Answer 10

thymidine kinase (from the herpes) – > acyclovir monophosphate; two kinases from host –> acyclovir di/tri phosphate

Question 11

Name the active form of acyclovir

Answer 11

acyclovir triphosphate

Question 12

What is the mechanism of action for acyclovir triphosphate

Answer 12

acyclovir triphosphate will be incorporated into growing viral DNA;
Viral DNA replaces deoxyguanosine by viral DNA polymerase;
Viral DNA chain terminates and further DNA replication is blocked

Question 13

true or false: acyclovir triphosphate works to block viral DNA replication?

Answer 13

TRUE

Question 14

how can a herpesvirus resist acyclovir?

Answer 14

mutants may lack thymidine kinase; the prodrug will never be phosphorylated and therefore never activated.

Question 15

which drug is a water soluble cyclic amine

Answer 15

amantadine

Question 16

what is the trade name for amantadine

Answer 16

symmetrel

Question 17

Amantadine works on which group of viruses?

Answer 17

influenza A viruses

Question 18

how does amantadine work?

Answer 18

inhibits influenza a viruses by blocking viral uncoating; targets the M2 transmembrane channel by blocking it and ending ion channel activity, preventing uncoating

Question 19

This drug is most effective when given propylactically to susceptible patients in anticipation of infection?

Answer 19

amantadine (for influenza a virus)

Question 20

which drug targets the M2 transmembrane channel?

Answer 20

amantadine

Question 21

Tamiflu is the trade name for what drug?

Answer 21

oseltamivir phosphate

Question 22

what is the mechanism of action for oseltamivir phosphate?

Answer 22

inhibits neuraminidase enzyme synthesized by A and B influenza

Question 23

what is neuraminidase?

Answer 23

It is a glycoprotein on the surface of influenza a and B viruses. It facilitates the release of progeny visions (helps with budding)

Question 24

Zidovudine is also known as what?

Answer 24

azidothymidine, AZT, Retrovir (tn)

Question 25

This drug requires phosphorylation by cell enzymes only

Answer 25

AZT

Question 26

AZT is phosphorylated by cell enzymes to what?

Answer 26

triphosphate thymidine analog

Question 27

How does zidovudine work?

Answer 27

inhibits viral reverse transcriptase (once phosphorylated) and causes chain termination (blocks proviral DNA)

Question 28

What is the only drug that causes toxicities to humans?

Answer 28

zidovudine (AZT)

Question 29

What are the major toxicities caused by AZT?

Answer 29

anemia and granulocytopenia (45%)

Question 30

This is the only drug considered a maintenance drug

Answer 30

zidovdine

Question 31

This drug inhibits viral reverse transcriptase?

Answer 31

AZT

Question 32

How do protease inhibitors work?

Answer 32

inhibit viral proteases that cleave viral polyproteins into active proteins (prevents activation of viral polyproteins)

Question 33

Name 3 protease inhibitors

Answer 33

saquinavir, indinavir, ritonavir, lopinavir