Week 10 - Nucleoside Analogues, Antivirals for Hep C, and Influenza

Question 1

Nucleoside analogues: examples

Answer 1

Acyclovir, famciclovir, valacyclovir

Question 2

Nucleoside analogues (-cyclovir): MOA

Answer 2

Interferes with DNA synthesis and inhibits viral replication

Question 3

Nucleoside analogues (-cyclovir): ADR

Answer 3

HA, N/V, skin rash, elevated transaminases, nasopharyngitis, fatigue, depression

Question 4

Nucleoside analogues (-cyclovir): caution and contraindications

Answer 4

• Caution in renal impairment
• Acyclovir recommended in pregnancy, lactation, pediatrics >2 years

Question 5

HCV meds

Answer 5

Ledipasvir/Sofosbuvir, sofosbuvir/velpatasvir

Prescribed by hepatologist

Question 6

HCV: MOA

Answer 6

Inhibits HCV protein necessary for viral replication

Tx based on genotype and stage of disease

Question 7

HCV: ADR

Answer 7

HA, fatigue, N/D, myalgias, pruritus

Question 8

HCV: caution and contraindications

Answer 8

• BLACK BOX: hep B virus reactivation
• Avoid in pregnancy; limited data in lactation

Question 9

Influenza: examples

Answer 9

Oseltamivir (Tamiflu), Zanamivir (Relenza), Peramivir (Rapivab), Baloxavir marboxil

Question 10

Oseltamivir, Zanamivir, Peramivir: classification

Answer 10

Neuraminidase inhibitor

Question 11

Neuraminidase inhibitors: MOA

Answer 11

Neuraminidase is a viral enzyme responsible for cleaving viral attachment to the host cell surface, allowing for viral circulation

Inhibiting this enzyme prevents release of virus and halts spreading of infection

Effective against influenza A and B

Question 12

Neuraminidase inhibitors: caution and contraindications

Answer 12

• Caution in pregnancy (Tamiflu recommended in lactation)
• Caution in renal and hepatic impairment
• Avoid Zanamivir w/ hx of respiratory disease

Question 13

Neuraminidase inhibitors: ADR

Answer 13

HA, N/V

Rare: anaphylaxis, neuropsychiatric events

Question 14

Baloxavir marboxil: MOA

Answer 14

Dependent endonuclease inhibitor that interferes w/ viral RNA transcription –> inhibition of influenza virus replication

Question 15

Baloxavir marboxil: ADR

Answer 15

Diarrhea, nasopharyngitis

Question 16

Baloxavir marboxil: caution and contraindications

Answer 16

• Other agents recommended in pregnancy and lactation
• Avoid in pregnancy <12 years

Question 17

Nucleoside analogues (-cyclovir): indications

Answer 17

Herpes simplex (herpes labialis, herpes genitalis)

Question 18

Acyclovir: indications

Answer 18

• Herpes simplex virus 1, 2, and 6
• Varicella zoster
• Epstein-Barr virus
• CMV

Question 19

Valacyclovir: indications

Answer 19

Converted to acyclovir after PO administration –> active against same viruses

Question 20

Famciclovir: indications

Answer 20

• HSV-1, HSV-2
• Varicella zoster
• Epstein-Barr virus
• Hep B

Question 21

Ganciclovir: indications

Answer 21

CMV

Question 22

Nucleoside analogues (-cyclovir): ADR

Answer 22

• Acyclovir/valacyclovir*: few ADRs when given PO
• Valacyclovir*: thrombocytopenia purpura, hemolytic uremic syndrome in immunocompromised patients
• Famciclovir*: HA
• Ganciclovir*: granulocytopenia, anemia, thrombocytopenia, may be carcinogenic

Question 23

Nucleoside analogues (-cyclovir): patient education

Answer 23

• BUN and creatinine will be monitored
• Maintain adequate hydration
• Monitor for symptoms of renal failure, encephalopathic changes, blood dyscrasias

Question 24

HCV: drug interactions

Answer 24

Co-administration of ledipasvir, sofosbuvir (Harvoni), and amiodarone can cause serious symptomatic bradycardia

Question 25

True/False: Oseltamivir is a prodrug

Answer 25

True

Question 26

Influenza (zanamivir): ADR

Answer 26

Bronchitis and SOB (bronchospasms)

Avoid in asthma/COPD