Antivirals Flashcards
Viruses are obligate ?
intracellular parasites
Antiviral treatment may be for?
Prophylaxis (to prevent infection)
Pre-emptive therapy (when evidence of infection detected, but before symptoms apparent)
Overt disease
Suppressive therapy (to keep viral replication below the rate that causes tissue damage in asymptomatic infected patient)
What do antivirals not eradicate?
virus from latently infected cells, e.g. herpes viruses
= more treatment may be needed
ANTIVIRALS IN PRACTICE
Herpesviruses
HIV
Hepatitis
Respiratory
Use of Antivirals for HSV & VZV
Herpes simplex
Chickenpox
Shingles
Antivirals used for HSV & VZV
4
aciclovir - oral, IV, eye ointment, cream
valaciclovir oral
famciclovir oral
foscarnet IV
Antivirals and CMV
ganciclovir IV, ocular implant
valganciclovir Oral
cidofovir IV
foscarnet IV
Antivirals and HIV
Combination anti-retroviral therapy (cART), also called highly active antiretroviral therapy (HAART), uses combinations of antiretrovirals
Antivirals for chronic hepatitis B - 2 types and examples
Pegylated interferon alpha (subcut.)
Nucleoside/tide analogues::
Tenofovir Adefovir Entecavir Lamivudine Emtricitabine Telbivudine
Antivirals for chronic hepatitis C - current therapies and combinations
Often 12 to 48 weeks
Current therapies
Pegylated interferon alpha (subcut.) & ribavirin (oral)
As above, PLUS protease inhibitor (telaprevir or boceprevir)
New directly-acting antivirals, in combination daclatasvir sofosbuvir simeprevir Rapidly evolving field !
Antivirals and respiratory infections - Influenza A or B: ?
oseltamivir, zanamivir
- treatment and prophylaxis
- within 48 hours of onset of symptoms/contact
Resistance to Antivirals
Testing is?
Phenotypic – can virus grow in presence of compound, e.g. HSV
Genotypic – Sequence genome and identify resistance-associated mutations, e.g. HIV
Suspect that there is resistance to the herpes virus in immunocompromised if there is no?
response to appropriate antiviral doses within 7 days.
