Anti viral Flashcards
What are the main categories of antiviral agents?
- Agents that disrupt viral attachment, penetration, and early viral replication. 2. Agents that interfere with viral fusion to host cellular membranes or entry. 3. Viral replication inhibitors. 4. Protease inhibitors and other antiretroviral agents.
What is the mechanism of action of Amantadine?
It inhibits penetration of RNA virus particles into the host cell and inhibits the uncoating of the viral genome.
Which antiviral agent is more effective than amantadine against influenza A virus?
Rimantadine
What are interferons?
Natural mediators of immune response.
List the types of interferons.
- α-interferon
- β-interferon
- ɤ-interferon
What is the role of neuraminidase (NA) in influenza viral infection?
NA removes sialic acid from surface glycoproteins, aiding in viral adsorption and infectivity.
What is Oseltamivir phosphate used for?
It is the first orally administered NA inhibitor used against influenza A and B.
What is the route of administration for Zanamivir?
Nasal, intraperitoneal, and intravenous routes.
What do fusion inhibitors do?
They inhibit the attachment or fusion of host and viral membranes, preventing virus entry.
Name two fusion inhibitors used for AIDS treatment.
- Enfuvirtide
- Maraviroc
What is the function of Idoxuridine?
It inhibits DNA polymerase and causes faulty viral protein formation.
What is Ribavirin’s broad-spectrum activity against?
Both DNA and RNA viruses, including influenza, herpes, measles, CMV, and acute hepatitis.
What type of viruses is Acyclovir used for?
DNA viruses including HSV-1 and HSV-2.
What is the primary action of Cidofovir?
It is a synthetic acyclic pyrimidine nucleotide analog used for HSV-1, HSV-2, VZV, CMV, and EBV.
What distinguishes non-nucleoside analogs from nucleoside analogs?
Non-nucleoside analogs have no structural similarities with nucleosides.
What was Fomivirsen used for?
It was the first antisense oligonucleotide agent approved for CMV retinitis.
What is the mechanism of action of protease inhibitors?
They prevent posttranslational processing and budding of immature viral particles.
What is zidovudine an analog of?
Thymidine
What are nucleoside reverse transcriptase inhibitors (NRTIs)?
Prodrugs that must be phosphorylated and compete with natural substrates for incorporation into proviral DNA.
What does Didanosine cause when incorporated into viral DNA?
Chain termination due to the absence of a 3-hydroxyl group.
What is the role of nonnucleoside reverse transcriptase inhibitors (NNRTIs)?
They bind to RT, blocking the DNA and RNA dependent polymerases function.
Which HIV integrase inhibitor acts by chelation of a divalent cation?
Raltegravir
What is the primary metabolism pathway for Nevirapine?
Oxidative pathway via CYP3A4.
What is the limitation of Enfuvirtide?
Mutations leading to resistance.
Fill in the blank: Zanamivir is administered via _______.
[nasal, intraperitoneal, intravenous routes]
True or False: Ribavirin is solely effective against RNA viruses.
False
