Antivirals Flashcards
4 classes of RNA viruses?
orthomyxovirus
orthocoronavirus
retrovirus
flavivirus
name the 3 orthomyxoviruses?
influenza A
influenza B
RSV
name the retroviruses?
HIV-1
HIV-2
name the falvivirus?
Hep C virus
2 classes of DNA viruses?
herpes viruses
hepadnaviruses
name the 4 herpes viruses?
HSV-1
HSV-2
varicella-zoster virus
CMV
name the hepadnavirus?
hep B virus
what is the challenge for antiviral therapy?
have no cell wall or cell membrane
2 synthetic nucleoside analogs that are phosphorylated into nucleotides and taken up by viral DNA polymerase as “false substrates” during the acute phase of infection
acyclovir
valacyclovir (prodrug)
3 uses for acyclovir and valacyclovir?
HSV-1
HSV-2
VZV
topical ADR of acyclovir and valacyclovir? oral? IV? in patients with impaired renal function?
TOPICAL:
burning
stinging
mild pain
ORAL:
headache
IV:
phlebitis
IMPAIRED RENAL FUNCTION:
nephrotoxicity
4 synthetic nucleoside analogs that get phosphorylated into monopotassium phosphate (PO4) by viral thymidine kinase in HSV or VZV-infected cells OR UL97 kinase in CMV-infected cells
penciclovir
famciclovir (prodrug)
ganciclovir
valganciclovir (prodrug)
2 uses for penciclovir and famciclovir?
HSV
VZV
3 ADR of penciclovir and famciclovir?
TOPICAL:
burning/pain
ORAL:
headache
2 uses for ganciclovir and valganciclovir?
CMV
CMV retinitis in AIDS
3 ADRs of ganciclovir and valganciclovir?
headache
allergic reaction
bone marrow suppression
3 monophosphate nucleoside analogs that do not need the viral kinase to phosphorylate and can overcome viral resistance due to deficient or mutated thymidine kinase or UL 97 kinase
cidofovir (IV)
trifluridine (PO, eye)
vidarabine (PO, eye)
2 uses for the monophosphate nucleoside analogs?
acyclovir-resistant HSV kerato-conjunctivitis
CMV retinitis
anti-viral that directly inhibits viral DNA polymerase by targeting HIV reverse transcriptase (who converts viral RNA into viral DNA)
foscarnet (IV)
2 uses for foscarnet?
acyclovir-resistant HSV
ganciclovir-resistant CMV
4 ADRs of foscarnet?
“fast cars make me feel imbalanced (electrolytes), nephrotoxicity, hot (fever) and weak (anemia)
nephrotoxicity
electrolyte imbalance
fever
anemia
why is foscarnet hardly used?
caused ARDS
unsure MOA, possibly inhibits viral fusion; used OTC and started within 12 hours of symptoms
docosanol
(zilactin-B, blistex, erazaban)
use for docosanol?
recurrent orolabial herpes
2 ADRs of docosanol?
headache
allergic rxn (rare)
target and bind to spike protein of COVID-19, block antigen from binding to cells or “mark” it for processing by immune cells
monoclonal antibodies
nucleoside triphosphate analogue that inhibits viral RNA polymerase and stops the inclusion of additional nucleosides
remdesivir (IV)
remdesivir use?
COVID-19
why does remdesivir have low efficacy, especially on ventilated patients?
infection spreads before patient has symptoms
what is the median incubation period of COVID-19? when should remdesivir be started?
4 days
8 hours - 2 days of infection
kinase inhibitor that interferes with the main protease enzyme of COVID-19
paxlovid (oral)
ADR of paxlovid?
rebound of symptoms after full course and viral clearance
2 paxlovid uses?
contain COVID-19 pandemic
decrease hospitalizations and deaths
not yet approved for use but reserved for patients who cannot respond or tolerate paxlovid
molnupiravir
used as pre-exposure prophylaxis for COVID-19 infection in patients at risk for the infection and are allergic to the vaccine
evusheld (tixagevimab/cilgavimab)
4 ADRs of COVID-19 vaccine?
injection site reaction
fatigue
headache
myalgia
what is considered the 1st line treatment for HIV?
NRTI’s (nucleoside reverse transcriptase inhibitors)
what is the goal of HIV treatment?
slow or reverse the increase in viral RNA load that is associated with disease progression
what is the Highly Active Anti-Retroviral Therapy (HAART) regimen?
2 NRTIs + INSTI
what is the HAART alternative #1?
2 NRTIs + NNRTI or boosted protease inhibitor
what is the HAART alternative #2?
1 NRTI + INSTI
fusion inhibitor that blocks fusion between the virus and target cell membrane extracellularly
enfuvirtide (SQ)