Antivirals (non-HIV) Flashcards
Herpes Simplex Viruses
A ___ virus that can cause several different types of infections
HSV1: ___
HSV2: ___
dsDNA
oral
genital
Acyclovir Quick Facts
A Prodrug that is converted to active form acyclovir triphosphate via triphosphoylation
MOA:
- inhibits viral DNA polymerase to inhibit viral replication
- incorporated into viral DNA causing premature chain termination
- renally dose adjusted
- AdjBW
SE
- N/V/D
- Nephrotoxicity
- Neurotoxicity
Genital and oral HSV
HSV encephalitis
10mg/kg IV q8hr for 14-21 days (adjusted body weight)
HSV encephalitis
10mg/kg IV q8hr for 14-21 days (adjusted body weight)
Valacyclovir Quick Facts
A prodrug of ___ (same MOA, adverse effects, and spectrum)
- Bioavliability of acyclovir is 3-5 greater with valacyvlovir (55%) formulation
- renally eliminated (adjusted
acyclovir
Famciclovir Fast Facts
Prodrug of ___ converted to active form via triphosphorylation
Drug interaction: probenecid + famciclovir decreases renal clearance, increases serum concentrations
generally well tolerated
- Acute renal failure
- renal dose adjust
- penciclovir
Varicella Zoster Virus
A ___ virus that causes the infections commonly referred to as chickenpox and shingles
- Acyclovir, Valacyclovir, Famciclovir
DNA
Cytomegalovirus
Common virus found in people of all ages
- In those with weak immune systems can cause serious infections most commonly in the ___ and can even cause end organ damage
eyes
Cytomegalovirus
Ganciclovir MOA
- HSV/VZV: a prodrug turned into the active form by viral thymidine kinase
- CMV: a pro drug converted to its active form mono-phosphorylated by a CMV-encoded protein kinase (UL97 gene), then to di- and triphosphate forms by cellular kinases (triphosphorylation)
MOA: inhibits viral DNA polymerase and/or incorporation into viral
DNA which inhibits viral replication
Resistance can develop via a UL97 gene mutation
Adequate concentrations in ___ , brain tissue, and ___
___ ___ suppression
CSF, eye
Bone marrow
Valganciclovir Fast Facts
Prodrug of ganciclovir (rapidly converted to ganciclovir by intestinal and hepatic esterases)
- MOA and adverse effects same as ganciclovir ( ___ toxicity!)
- counsel to take with food
CMS retinitis and transplant pts
- hematologic
MSC
Letermovir MOA
- Inhibits the pUL56 subunit of the viral terminase complex of cytomegalovirus (CMV)
- End result – inhibition of CMV ___ and prevention of CMV infection
- Highly protein bound ~99%
- Lots of drug interactions!!! ( ___ inhibitor; substrate and inhibitor of organic aniontransporting polypeptide 1B1/3 (OATP1B1/3) transporters)
Prophylaxis of CMV in HSC ___
AE
- N/V/D
- peripheral edema
- cough
- fatigue
- abdominal pain
- HA
replication
CYP3A4
transplant
Foscarnet Fast Facts
Directly inhibits viral DNA polymerase (does not require ___ by thymidine kinase or other kinases)
- last line in drug resistant HSV, VZV, and CMV
- Only available IV due to poor oral absorption
- ___ sequesters 10-20% of dose
___ – major dose-limiting adverse effect
CMV retinitis, HSV and VZV (resistant)
phosphorylation
bone
Nephrotoxicity
Influenza - Neuraminidase Inhibitors
Zanamivir - ___
Oseltamivir (Tamiflu®) - prodrug
Peramivir - ___ formulation
- inhale
- IV
Oseltamivir
Treatment of influenza infection in patients ≥ 2 weeks of age who have been
symptomatic for no more than ___ days (not approved for < 1 year old)
Do not administer the live attenuated influenza vaccine (intranasal) within 2
weeks before or 48 hours after administration of oseltamivir
2
Zanamivir
inhaled
Treatment of influenza infection in patients ≥ 7 years of age who have been
symptomatic for no more than __ days
Do not administer the live attenuated influenza vaccine (intranasal) until 48
hours after cessation of zanamivir
Not recommended in patients with underlying respiratory disease (e.g., asthma, COPD)
2
Peramivir
First ___ available neuraminidase inhibitor (oral bioavailability ~ 2%)
Potent inhibitor of both influenza A and B; structurally different than oseltamivir
and zanamivir less ___
Drug interactions – avoid use of live attenuated influenza vaccine (intranasal)
within 2 weeks before or 48 hours after administration of peramivir
Not approved for serious influenza requiring hospitalization
- Indicated for treatment of acute ___ influenza in patients 18 years or older who have been symptomatic for no more than __ days
SINGLE DOSE
parenterally
cross resistance
uncomplicated
2
Baloxavir Marboxil
MOA: inhibits polymerase acidic (PA) endonuclease (influenza specific enzyme in the viral DNA polymerase complex required for viral gene transcription) -> inhibition of ___ synthesis and viral replication
___ completely converted to active baloxavir by hydrolysis
Avoid co-administration with dairy product
Acute uncomplicated influenza in patients >12 years of age who have been symptomatic for no more than 48 hours
mRNA
Prodrug
SoA
acyclovir and valacyclovir, Famciclovir
HSV, VZV
SoA
Ganciclovir, Valganciclovir, Letermovir
CMV
SoA
Foscarnet
HSV, VZV, CMV, EBV
broad spectrum
