Antivirals part 2

Question 1

What does influenza neuraminidase do?

Answer 1

Cleaves terminal sialic acid residues on cell surface of infected cells. This is required for the release of the virus from infected cells.

Question 2

What is the MOA of Oseltamivir and Zanamivir?

Answer 2

Sialic acid analogs that prevent the release of the virus; Inhibitors of influenza A and B neurominidases by causing a conformational change in the enzyme’s active site.

Question 3

What is the resistance to Oseltamivir and Zanamivir?

Answer 3

Mutation to neuraminidase

Question 4

What are the pharmacokinetics of Oseltmavivir?

Answer 4

1. Rapid absorption and acitvation by esterases in GI tract

2. Cleared by kidneys

Question 5

What are the pharmacokinetics of Zanamivir?

Answer 5

1. Low oral bioavailability

2. Oral inhalant

Question 6

What are the side effects of Oseltamivir and Zanamivir?

Answer 6

Oseltamivir: GI upset
Zanamivir: Wheezing, Bronchospasm, throat discomfort

Question 7

When is the infectious period of RSV?

Answer 7

November to April

Question 8

What is the MOA of Ribavirin?

Answer 8

Inhibits both RNA and DNA viruses secondary to alteration of cellular nucleotide pools.

Question 9

What are the side effects of Ribavirin?

Answer 9

Wheezing, increased bilirubin and anemia.

Question 10

What is the MOA of interferon alfa-2b?

Answer 10

1. Inhibits cell growth
2. Interferes with oncogene expression
3. Increases phagocytic activity of macrophages

Question 11

What are the pharmacokinetics of Interferon alfa-2b?

Answer 11

Not active if given orally

Question 12

What are the side effects of Interferon alfa-2b?

Answer 12

1. Flu-like illness

2. Pulmonary symptoms.