Antiviral therapy Flashcards
4 malignancies associated with viruses
- cervical cancer - HPV
- anal - HPV
- hpatocellular carcinoma - Hep B
- lymphomas - EBV
3 ways to prevent viruses
- infection control
- vaccination
- Ig
3 types of antivirals
- immune modulators
- virucidal agents - directly inactivate viruses
- antiviral meds - inhib. replication
** what is main antiviral shown to reduce HSV-2 infections
valcyclovir
9 steps to viral rep
- adsorptions
- penetration
- uncoating
- transcritpion
- translation
- processing
- replication
- assembly
- budding
what is main virus specific step to hit
nucleic acid synthesis
4 factors that favor viral resistance development
- high viral replicative load
- high intrinsic mutation rate
- degree of drug exposure
- ability to mutate without affecting viral fitness
herpesvirus structure
DNA in envelope
key common feature in all herpes
latency
*** antivirals against VZV and HSV (3)
acyclovir + 2 prodrugs valacyclovir and famciclovir
**2 antivirals for CMV
ganciclovir and valganciclovir
**what is first step in nucleoside mech
must be phosphorylate by viral kinase and then activated by cellular enzymes
** second step in nucleoside mech
similar to nucleotides, but missing OH group
** third step
used and a nucleotide and terminated sequences
2 times to worry about resistence
- persistent or worsening herpes in immunocompromised
2. persistent worsening CMV in HIV pt on ganciclovir
when to use VZV antivirals
- shingles
- in HIV PT
- shingles in V1 dermatome
what to use for kaposi sarcoma in HIV PT
treat with antiretrovirals, not anti herpes
when are flu drugs used
- prevent infections in outbreaks
2. treat individuals
2 MOA of anitflu
adamantanes - target uncoating by M2 ion channel blocker - can’t get in
neuraminidase inhib - stop clusters from being freed after release
**1 neuraminidase to know
oseltamivir - tamiflu
**3 anti virals for Hep B
lamivudine tenofovir entecavir - nucleoside analogs - alone or in combo
** 2 drugs for hep C
- interferon
2. ribavirin - guanaside analogue
** 1 drug to know for HPV
imiquimod - activates immune cells to produce antiviral cytokines
8 factors to consider with antiviral therapy
- age
- site of infection
- stage of illness
- underlying disease
- latency of virus
- genetic stability of virus
- dev. of resisitance
- cost and route of admin
when to give HSV drugs (5)
- child with leukemia
- maybe genitals to shorten Sx
- HSV encephalitis
- keratitis (eye)
- neonatal herpes
when to give CMV drugs
- retinitis in adv HIV
2. esophageal ulcer
