Flashcards in Anti-virals Deck (14):
Can a virus replicate independently?
Describe the structure of a virus.
- lipoprotein membrane
- Nucleoid: DNA or RNA core
- Surface proteins
- Core proteins (capsid)
What are the 4 main types of anti-viral therapy?
1. reverse transcriptase inhibitors
2. protease inhibitors
3. Absorption and fusion inhibitors
4. anti-viral cytokine therapy
What is HIV?
Mostly infects T4-lymphocytes (express CD4)
Uses cell surface receptors as ports to gain entry in to cell.
What are the 2 main classes of drugs used in anti-viral therapy?
Reverse transriptase inhibitors and protease inhibitors.
What is HAART?
A current therapeutic approach.
'Highly active anti-retroviral therapy' - a combo of 3 drugs to prevent resistance.
What are NRTIs? What do they do?
Nucleoside reverse transcriptase inhibitors. (ZIDOVUDINE) = SLOW RESISTANCE
Block conversion of viral RNA -> DNA.
They are prodrugs.
triphosphate metabolite is incorporated into and terminates the DNA chain.
Zidovudine was originally what?
An anti-cancer drug.
What does zidovudine do?
Selective for viral RT but doesn't effect mammalian DNA pol. It is phosphorylated 3 times and goes into DNA and stops it.
Can cause pancreatitis, liver damage, severe anaemia.
What are NNRTIs?
Non-nucleoside reverse transcriptase inhibitors.
(NEVIRAPINE - lacks selective toxicity)
Useful as part of HAART.
What do protease inhibitors do?
Bind to active site of protease, inhibiting function.
Nausea, vomiting, diarrhoea.
Used in combo.
What is a first fusion inhibitor?
inhibits entry of HIV into host.
adverse side effects.
What is involved in cytokine therapy?
IFN-a is a naturally occurring glycoprotein secreted by cells due to infection.
Inhibits viral replication in infected cells.
Needs to be administered 3 times a week for chronic hepatitis C.