1.1.4 Antiviral Chemotherapy Flashcards
What is the viral life cycle?
- Bind to and enter susceptible host cell
- Uncoating, release of viral genome
- After variable dormant period, synthesize “early” proteins (polymerases)
- Synthesis of nucleic acids
- Synthesis of “late” proteins (structural)
- Assembly of viral particles, release of virus
Class of drug of rimantadine?
Inhibitor of uncoating (anti-influenza chemotherapy)
What is the MOA of rimantidine? Administration route? Side effects?
What class of drug do oseltamivir and zanamivir belong to?
Viral neuraminidase inhibitors (anti-influenza chemotherapy)
What is the MOA of oseltamivir? Administration route? Side effects?
Neuraminidase inhibitor - prevents viral release and subsequent infection of additional cells
*Works best if given early in the course of infection b/c it is used to limit spreading b/t cells and has little effect once the cell has been infected
What is the MOA of Zanamivir? Administration route? Contraindication?
Viral NA inhibitor - prevents release and subsequent infection of additional cells
What class of drug does ribavirin belong to?
Anti-metabolite - Inhibitor of viral nucleic acid synthesis
In which subset of patients is ribavirin contraindicated in?
Pregnant pts - ribavirin is a known teratogen and embryotoxin
How is ribavirin administered for pts with RSV? for Hep C virus?
RSV: aerosol
Hep C virus: oral
What is the MOA of ribavirin?
Anti-metabolite
What are the stages that can define selective toxicity?
Kinase and polymerase
What effect does dideooxynucleosides have on viral genome replication?
Chain termination
-No site to add another base on the chain
What is acyclovir?
Guanosine analogue
What is the MOA of Acyclovir? How is it activated? Administration route?
Guanosine analogue - inhibits viral genome replication
What is the mechanism of resistance found in viruses?
TK-
acyclovir doesn’t get its initial phosphorylation
What is valacyclovir?
Valine ester of acyclovir, increased biavailability because GI absorption through peptide transporter
What is ganciclovir used to treat?
Cyctomegalovirus (CMV); inhibition of viral genome replication
Administration route of ganciclovir? Initial phosphorylation?
What is the difference b/t ganciclovir and acyclovir? How does this manifest itself?
What is the MOA of foscarnet? What is it used to treat?
Directly inhibits viral polymerases (DNA, RNA, RT); CMV and resistant herpes
How is foscarnet administered? Side effect?
What is the MOA of cidofovir? What is used to treat? Drug is given in combination with cidofovir?
Anti-Herpes Agent
What is the MOA of Trifluridine? How is it activated? Route of admission?
What is the MOA of interferon-alpha? What is it used to treat? What increases it half life?
cytokines analog that helps trigger and immune response
Hep B and C
Pegylated (polyethyleneglycol)
What is the standard of care for eradication of HCV?
Pegylated INF-alpha + ribavirin
What is the MOA of lamivudine (3TC)
Cytosine analog that inhibits HIV RT and HBV DNA polymerase
What is the MOA of telaprevir and simeprevir?
Protease inhibitors for HCV
What characteristic of teleprevir causes increased chance of drug-drug interactions?
CYP3A and Pgp substrate/inhibitor
What is th adminstration route for telaprevir and simeprevir?
What is the MOA of sofosbuvir?
Nucleotide analog that inhibits HCV RNA polymerase
What combination of treatments can be curative for HCV?
Ribavirin + interferon + sofosbuvir
