Lecture 7: Antiviral Agents I Flashcards
Which of the following antiviral drugs prevents the attachment and penetration of viral particles into the host cell (first phase)?
A. Palivizumab
B. Amantadine
C. Oseltamivir
D. Immune Globulin
D. Immune Globulin
____ is a monoclonal antibody to the F protein of respiratory syncytial virus (RSV)
A. Palivizumab
B. Amantadine
C. Oseltamivir
D. Immune Globulin
A. Pavilizumab
____ is a tricyclic primary amine that acts on the host cell to block viral penetration and uncoating, inhibit release of infectious nucleic acid into the cell cytoplasm, by buffering pH of endosomes
A. Palivizumab
B. Amantadine
C. Oseltamivir
D. Immune Globulin
B. Amantadine
Amantidine blocks the __ viral protein channel required for nucleocapsid release
A. M1
B. M2
C. HCS1
D. STAT
B. M2
Which AE reactions are associated with amantadine?
CNS Effects
True or False: Amantadine is effective against Type B Influenza
False - it is NOT
Amantadine can also be used as an ____ agent
anti-parkinsonian
Which two surface antigens are found in Type A Influenza?
Hemagglutinin and Neuaminidase
In type A influenza viruses, ___ is responsible for attachment of virus to sugary “hooks” on cells (sialic acid residues) and penetration of virus into cell during initial stages of infection
Neuroaminidase (NA)
___, a membrane protein attached to the surface of the influenza virion, facilitates viral mobility to and from site of infection, important for virus spread.
Neuroaminidase (NA)
Which molecule cleaves the linkages between sialic acid and hemagglutinin from both itself and the infected cell surface?
A. Neuroaminidase (NA)
B. Neuroaminidase (NA)
A. Neuroaminidase
What are three reasons that Neuroaminidase is a good target for the flu?
- NA is different in humans
- The business end of viral NA, the part of the enzyme that actually breaks NA-sialic acid bond, is chemically identical in all influenza strains
- NA is critical for influenza virus replication
True or False: Amantadine can only treat Influenza A while Zanamivir is effective against ALL strains of Influenza A and B
True
Which of the following inhibits influenza virus neuraminidase?
A. Olseltamivir
B. Relenza
C. Peramivir
D. Zanamivir
D. Zanamivir
What is the major difference/advantage of Oseltamivir over Zanamivir?
- Oseltamivir (Tamiflu) can be taken as a pill, rather than inhaled
- It acts systemically
___ is a purine nucleoside analog that is structurally similar to guanosine and is attached to a 1,2,4-triazole-3-carboxamide moiety
A. Olseltamivir
B. Relenza
C. Peramivir
D. Zanamivir
E. Ribavirin
E. Ribavirin
___ is a purine nucleoside analog that is structurally similar to guanosine and is attached to a 1,2,4-triazole-3-carboxamide moiety
A.
Once phosphorylated via cellular enzymes, ____ is the intracellular form of ribavirin
ribavirin-5’-triphosphate
True or False: Ribavirin inhibits viral DNA, polymerases, and mRNA synthesis
False - it inhibits viral RNA and polymerase + mRNA
True or False: In virus-infected cells in vitro, ribavirin generally exhibits a lesser affinity for inhibition of viral RNA synthesis than cellular RNA synthesis
False - In virus-infected cells in vitro, ribavirin generally exhibits a GREATER affinity for inhibition of viral RNA synthesis than cellular RNA synthesis
What is the primary condition that Ribavirin treats?
RSV (respiratory syncytial virus infection)
Why should ribavirin not be used in adults?
Teratogenic
Testicular lesions
True or False: An AE associated with Ribavirin use in infants includes: sudden deterioration of respiratory function
True
____ , a trifluoro analog of thymidine, is a new pyrimidine nucleoside antiviral agent that INHIBITS viral and cellular DNA polymerase
A. Olseltamivir
B. Relenza
C. Peramivir
D. Zanamivir
E. Ribavirin
F. Trifluridine
F. Trifluridine
True or False: Both Ribavirin and Trifluridine are phosphorylated
True
True or False: Trifluridine inhibits viral RNA synthesis in mammalian cells
False - inhibits viral DNA!
Which condition does Trifluridine treat?
A. Hep C
B. Both Influenza A and B
C. Influenza A
D. Type 1 and 2 Herpes
D. Type 1 and 2 Herpes
Symptoms of herpes simplex infections?
Follicular conjunctivis and corneal ulcer
Visual haze and teratogenicity are AE associated with which drug?
Visual haze and teratogenicity are AE associated with which drug?
A. Olseltamivir
B. Relenza
C. Zanamivir
D. Ribavirin
E. Trifluridine
E. Trifluridine
Which drug is an ophthalmic solution for topical treatment of keratoconjunctivitis due to HSV (herpes simplex virus)?
A. Olseltamivir
B. Relenza
C. Zanamivir
D. Ribavirin
E. Trifluridine
E. Trifluridine
___ and ___ must be phosphorylated to be effective antiviral agent
Acyclovir (via: 1) viral thymidine kinase and 2) cellular kinases) and Trifluridine
True or False: Phosphorylation reaction involving acyclovir occurs much more slowly in herpes infected host cells than in non-infected human cells
False - Phosphorylation reaction involving acyclovir occurs much more QUICKLY in herpes infected host cells than in non-infected human cells
How does Acyclovir triphosphate inhibit viral DNA synthesis and viral replication?
Inhibits herpes viral DNA Polymerase
True or False: Trifluridine is a perfect example of an antimetabolite with SELECTIVE antiviral activity
False - Acyclovir has these features!
True or false: Acyclovir is typically non-toxic to normal human cells
True (no real AE’s…)
Conversion of acyclovir to acyclovir triphosphate leads to ___ chain termination
DNA
Which herpes virus specific kinase is responsible for the rapid phosphorylation of Acyclovir in the infected cell?
Thymidine Kinase
Ganciclovir Sodium is identical to Acyclovir EXCEPT it does have a few adverse effects, such as….
- Teratogenic/Carcinogenic
- Granulocytopenia/Thrombocytopenia
- Severe myelosuppression
True or False: Acyclovir is the drug of choice for treating cytomegalovirus retinis
False - Ganciclovir Sodium is!
_____ is a drug that inhibits viral DNA Polymerase and is used to cytomegalovirus retinitis in patients with AIDS
A. Olseltamivir
B. Foscarnet
C. Zanamivir
D. Ribavirin
E. Trifluridine
B. Foscarnet
What is the main AE associated with Foscarnet?
Renal toxicity
____ are a family of species-specific proteins or glycoproteins
Interferons
What three cell types are interferons produced by?
- Peripheral blood leukocytes
- Fibroblasts
- Epithelial cells
____: obtained from strain of E. coli bearing genetically engineered plasmid containing interferon a-2b gene from human leukocytes
Interferon-a2B
What are the two principal mechanisms of interferons?
Inhibits viral protein synthesis and viral replication
Once bound to the cell membrane, how does interferon alpha act as an inhibitor of viral replication?
By inducing host cell to make enzymes that inhibit translation of viral mRNA to viral proteins (thereby inhibiting viral replication)
Which three cellular enzymes are made due to interferon alpha?
- Protein kinase
- Phosphodiesterase
- 2’5’ oligo adenylate synthetases
Three uses of Interferon alpha?
- Cutaneous warts
- Herpes keratoconjunctivitis
True or False: Interferon alpha may act as a anticancer agent agonist
True