Exam 3

Question 1

Viral Entry Inhibitors

Answer 1

Amantadine, Rimantadine, MOA: inhibits penetration of RNA virus into host cell (blocks influenza A virus M2 proton-selective ion channel)

Question 2

Viral Entry Inhibitor Coverage

Answer 2

Influenza A ONLY

Question 3

Viral Entry Inhibitor Pharmacology and PK

Answer 3

CNS entry, renal clearance, Convulsions w/ high doses (amantadine)

Question 4

Neuraminidase Inhibitors

Answer 4

Zanamivir (Relenza) Nasal, Oseltamivir (Tamiflu) Oral, peramivir (Rapivab) IV, MOA: transition state that mimics the oxonium cation intermedicate of sialic acid

Question 5

Neuraminidase Inhibitor Coverage

Answer 5

Influenza A and B

Question 6

Zanamivir

Answer 6

Inhalation route only, Resistance against is caused by mutations in the NA active site, decreased binding of drug

Question 7

Oseltamivir

Answer 7

prodrug, give w/ food, mechanism of resistance same as zanamirvir

Question 8

Interferons

Answer 8

Used for the treatment of hepatitis virus

Question 9

Interferon MOA

Answer 9

potent cytokines, activate the JAK/STAT pathway -> leads to protein synthesis that have antiviral effect (pegylated enhances T1/2)

Question 10

Agents used to treat Herpes Virus

Answer 10

Nucleoside Analogs: Acyclovir, Valacyclovir, Famciclovir, Penciclovir, Cidofovir, Ganciclovir, Valganciclovir, Idoxuridine, (exception: Docosonol, Foscarnet) Trifluridine, Cytarabine

Question 11

Acyclovir/Valacyclovir

Answer 11

lacks 3prime -OH, MOA: competitive inhibition of DNA polymerase, incorporate into DNA -> chain termination (valacyclovir has valine group, prodrug, Trojan horse like entry into body)

Question 12

Acyclovir/Valacyclovir PK

Answer 12

Val. has increased F, renal elimination unchanged, Hallucinations w/ high doses

Question 13

Famyclovir/Penciclovir

Answer 13

Fam is prodrug converted into penciclovir (used only topically), MOA: inhibits DNA polymerase, not a chain terminator though, long T1/2 vs acyclovir, ADE- urticaria, confusion

Question 14

Cidofovir (Vistide)

Answer 14

synthetic, CMV and EBV coverage, too, NO PO, nephrotoxic

Question 15

Ganciclovir/Valganciclovir

Answer 15

Valine prodrug ester present, MOA: like acyclovir, herpes & CMV, ADE: myelosuppression, nutropenia, thrombocytopenia, convulsions, coma

Question 16

Idoxuridine (Herplex)

Answer 16

analog of thymidine, polymerase inhibitor, incorporated into DNA, topically ONLY, for HSV keratoconjuctivitis, ADE: bone marrow tox.,

Question 17

Docosonol

Answer 17

blocks viral entry, use w/in 12 hours reduces healing time by 1 day

Question 18

Foscarnet

Answer 18

pyrophosphate analog (blocks pyrophosphate binding site), treats CMV retinitis, acyclovir resistant HSV, many ADE including chelation, nephrotoxicity

Question 19

trifluridine

Answer 19

use for ophthalmic infections, HSV, CMV, vaccinia, adenoviruses,

Question 20

cytarabine

Answer 20

topical/IV, for lymphoma, lukemia, herpes, toxic to bone marrow/kidneys, teratogenic

Question 21

Imiquimod

Answer 21

treats warts and skin cancers, MOA: TLR7 = upregulation of cytokines (indirect antiviral effect)