Antiviral_part1_Flashcards
What are viruses classified as in terms of replication?
Viruses are obligate intracellular parasites.
What are the general principles of antiviral drugs?
- Target a specific step in the virus life cycle.
- Timing of starting treatment is crucial.
- Duration of treatment varies.
- Number of drugs used may be specific.
For which diseases is antiviral therapy available?
- Respiratory syncytial virus (RSV)
- Influenza virus
- Herpesviruses (e.g., HSV, VZV, CMV)
- Hepatitis C virus (HCV)
- Hepatitis B virus (HBV)
- Human immunodeficiency virus (HIV)
What is the clinical significance of respiratory syncytial virus (RSV)?
RSV is a common cause of lower respiratory tract infection.
What type of virus is RSV?
RSV is an RNA-enveloped virus.
What does the envelope of RSV contain, and what is its role?
The envelope contains a fusion protein, which helps in viral attachment.
What is Palivizumab, and what is its mechanism of action?
Palivizumab is an entry/fusion inhibitor. It binds to the fusion glycoprotein of RSV, preventing viral entry and replication.
What are the clinical uses of Palivizumab?
Prevention of RSV infections in high-risk infants. Administered intramuscularly.
What are the highlighted properties of Palivizumab?
- It is an antibody.
- Targets fusion proteins.
What is Ribavirin used for?
Ribavirin is used to treat Hepatitis C Virus (HCV).
What is the mechanism of action of Ribavirin?
- Interferes with the synthesis of guanosine triphosphate.
- Inhibits capping of viral messenger RNA.
- Inhibits viral RNA-dependent polymerase.
- Inhibits the replication of both DNA and RNA viruses.
What is the mode of administration for Palivizumab?
Palivizumab is administered intramuscularly.
What is the cost-related note for Palivizumab?
Palivizumab is expensive.
What role does the fusion protein play in RSV?
It aids in viral attachment and subsequent entry into the host cell.
Which two drugs are mentioned in the context of antiviral therapy for RSV?
Palivizumab and Ribavirin.
What are the clinical uses of aerosolized Ribavirin?
It is used to treat severe RSV bronchiolitis or pneumonia and reduces the severity and duration of illness.
When should treatment for the influenza virus begin?
Treatment should start within 48 hours after the onset of illness.
What is the mechanism of action for Amantadine and Rimantadine?
They block the M2 ion channel of the viral membrane, preventing the uncoating of the RNA virus, thus stopping replication.
What are the uses of Amantadine and Rimantadine?
Treatment of influenza A infections. Prophylaxis of influenza A infections.
What are the limitations of Amantadine and Rimantadine?
Their use is limited due to a high rate of resistance.
How are Amantadine and Rimantadine administered?
They are oral drugs.
What is the mechanism of action for Baloxavir?
Baloxavir prevents the capping of viral mRNA, inhibiting replication of the virus.
How is Baloxavir administered?
It is given as a single oral dose.
What are the uses of Baloxavir?
It is used for the treatment and prophylaxis of influenza A and B infections.
What is the mechanism of action for Oseltamivir, Zanamivir, and Peramivir?
They are neuraminidase inhibitors that prevent the release of newly formed virions from the cell surface, reducing the spread of infection in the respiratory tract.
How is Oseltamivir administered?
It is an oral drug.
How is Zanamivir administered?
It is administered by inhalation.
How is Peramivir administered?
It is administered intravenously.
What are the clinical uses of Oseltamivir, Zanamivir, and Peramivir?
Treatment and prophylaxis of influenza A and B infections. Reducing the severity and duration of influenza symptoms and associated complications.
What is a notable characteristic of neuraminidase inhibitors?
They target the neuraminidase enzyme to prevent the release of virions, thus limiting viral spread.
